From: John Stapleton <[email protected]>
Date: Fri, 02 Feb 1996 11:45:48 +1000
Subject: Air filters '74 GTV
Hi all!
Trevor Allen wanted to know about air filters for his '74 GTV. I have the same 2 litre motor in my Alfetta GTV and have tried the standard filter, individual socks and a GTA type air box (with integral filter!). My experience is that the original air filter is pretty good and, in the Alfetta, it even has a pipe running forward to a hole that scoops in fresh cool dense air. However, we want to tinker a little and squeeze a few more horsepower and so we replace it. I initially replaced mine with 2 inch trumpets on each carburettor throat that were covered by oil impregnated foam socks with springs inside them so that they would not collapse under suction. This system was fine but the induction noise was quite high. The main drawback with this system was, as Trevor quite correctly flagged, the fact that we are drawing very hot air from under the bonnet of the car. This is NOT what we want! The engine receives less dense air, puts out less horsepower and the motor gets hotter into the bargain. Alfa Romeo showed us the way in the GTA, and more so in the TZ1 and TZ2, where they had an air box drawing cool pressurised air from the front of the car. I decided to build an aluminium air box with an integral filter that fitted over my trumpets. It was whilst planning this that I came across a Pace Engineering catalogue. Pace Engineering is located at 1 Correa Court, Doncaster East, Melbourne, Victoria, 3109, Australia (Tel. 03 9842 1201). Vin Sharp has made a fibreglass air box with an integral oil impregnated foam filter that fits both the Giulia GTV's and Alfetta GTV's. It is a tighter fit into the Giulia GTV as there is less room under the bonnet. Vin's air box doesn't seal well enough for use on dusty roads but is an excellent product considering the very small production run. The nett result is that I purchased one of these instead of reinventing the wheel and building my own. Unfortunately, my trumpets would not fit inside the new air box and so I had to purchase new curved ones from Vin that are specially made to complement his air box. The all up cost was a high Aus$500 (less an Alfa Romeo Owner's Club discount). The result is that my motor now runs noticeable cooler and much quieter (I can now hear the exhaust slip joint quite well - too well! - next job). I have yet to re dyno the motor and so can't quantitively tell if there is much of a horsepower gain. Basically, the moral is that Alfa Romeo did it very well to start with and any modifications have to be well thought out.
Regards
John Stapleton
1969 1750 GTV (Restoration project - slow)
1974 Alfa Sud (with 1988 1.7 twin carb running gear)
1977 Alfetta GTV (Very original and quite fast)
1981 Alfetta GTV (Daughter No.1)
1984 Alfa 33 1.5 TI (Daughter No.2)
1986 Alfa 33 1.5 TI (Daughter No.3)
1984 Toyota Landcruiser Station Wagon (Wet weather Alfa)
P.S. The Americans amongst you will have to overlook the fact that I have correctly spelt words such as Aluminium, Fibreglass etc. :-)
You will probably get a different opinion on cams from everyone you
talk to. I have tried them all and feel that for a street car used for
an occasional time trial and autocross the Autodelta 10.95 lift cams
are the best. I have successfully used them in all engines from 1300 to
2000. These cams are available from Ricambi and are rated 8L. Talk to
Gene Pechich at Ricambi. The cam was old part # CAM19 I don_t remember
the new part number.
The cam is ground by Columbo Barriani in Italy it_s duration is 280
30/70 70/30. Set these cams at 102 degrees on the intake and exhaust
for street use. If that doesn_t do it let me know and I_ll get the part
number for you.
TOM SAHINES ARA TECHNICAL HOT LINE
------------------------------
From: [email protected] (Luke Kowalski)
Date: Mon, 29 Jan 1996 11:28:25 -0700
Subject: cams
frank !
re: cam choice for a 2 litre.
I have been very happy with the 11.1 mm lift cams from Shankle. They were a
lot cheaper than the Culombo (sp?) set up and certainly provided more oomph
than the euro 1750 cams. The ones I installed in the Spider have only a
very slight flat spot around 2K rpm, excellent torque in the midrange, and
outstanding accl. in the more scary upper ranges. They, are, as most of
the aftermarket cams, regrounds. Regular valve adjustments have kept things
just fine for the three years they lived in my 74 Spider......
later
luke
------------------------------------------------------------
From: [email protected] (Rasor Associates )
Date: Wed, 28 Feb 1996 18:58:34 -0800
Subject: o-ring & 8L cams & cam timing reply
CAM TIMING
Best timing for stock 2l FI cams is 102 degrees for both. This is
straight up 12:00.
8L CAMS
I personally like the 8 cam from Ricambi. It was the Autodelta design
and develops max power at 6500 RPM but will easily pull to 7500. This
allows one to save their motor by keeping the revs down. The part
number for this
cam is AL5443A or CM19 it has a 10.95 lift.
TOM SAHINES ARA HOT LINE
------------------------------
From: [email protected] (Rasor Associates )
Date: Wed, 28 Feb 1996 19:14:21 -0800
Subject: CAMS RATING SYSTEM
Here is the cam rating system that is used by Alfa Ricambi. It was
developed by Shankle Automotive Engineering.
Performance Rank Explained - The higher the number the more performance
potential. The 'L' nomenclature was coined to allow for ranking between
existing higher Performane Rank numbers. (Using a letter sounded better
than saying '1/2') The 'L' is a design based on the root number, with
emphasis on Low End power.
Performance rank applies to lobe design, not the number of cylinders or
applications.
Rank 1 1300 Normal
Rank 2 1600 Normal
Rank 3 USA Spica
Rank 4 1600 Carb'd
Rank 5 2000 Euro, (105480320001)
Rank 6 1300 Veloce
Rank 7 1600 Veloce
Rank 7L Similar to Rank 7 w/emphasis on LOW END power
Rank 8 Extension of 1600 Veloce philosophy, for larger engines
Rank 8L Similar to Rank 8 w/emphasis on LOW END power
Rank 9 No longer used (Was a specific Autodelta cam)
Rank 10 Equivalent to an old (1960's) 10.5 Autodelta grind.
Rank 1OL Similar to Rank 10 w/emphasis on LOW END power
Rank 11 No longer used (Was a specific Autodelta cam)
Rank 12 No longer used (Was a specific Autodelta cam)
Rank 13 Race cams for larger engines, power to 8000*
Rank 13L Race cams for smaller engines, power to 7600*
* It's difficult to put racing cams into a nice neat pigeon hole Power
bands, performance characteristics, max power are dependent on the
total package the customer has brought together, these are general max
redline, "yours may vary".
TOM SAHINES ARA HOT LINE
------------------------------------------------------------
From: Dana Loomis <[email protected]>
Date: Fri, 05 Apr 1996 09:58:28 -0500
Subject: Euro cams for US 2000
After all the discussion about the US-spec 2000 engine's lack of "revviness"
I spent some time studying the cam data in the back of AR Ricambi's catalog.
I've heard for years that Alfa's stock cam set for the European-spec
(carbed) 2000 is a good upgrade for increasing performance in a street car.
Now I can see why. The Euro cams have somewhat greater duration, but the
difference in overlap is huge: 49 degrees for the US SPICA cam, vs 76 for
the carb cam! In light of this, I'm wondering whether changing to the
European cams is a simple matter of dropping them in, or whether there are
also issues of fuel flow and/or ignition timing that need to be ironed out
in order to take advantage of the improved breathing.
Thanks -- Dana Loomis
------------------------------------------------------------
From: [email protected] (Les Singh)
Date: Sun, 3 Mar 1996 22:55:42 GMT
Subject: Venturi Sizes
Brian
You asked whether anyone had tried 41 mm venturis. I have a set of 45 DCOEs
with 40 mm venturis that I tried on my GTV. I know that according to theory
and Passini's book, the "correct" size for the 1965 cc engine is 37 mm but I
found that the larger venturis worked well once I got the jetting right. The
engine pulled very strongly in 2nd and 3rd gears from around 3000 rpm with
the pedal floored and the sound of the open trumpets was awesome! The
jetting was 165 mains and 180 air I think, but I can check these if you're
interested. I have them written down somewhere. Something went wrong with
the carbs and I replaced them with 45DHLA Dell'Ortos which are on the car
now. These have 36 mm venturis with 135 mains and 220 air correctors. I also
run 40 mm venturis on these when I want to hear that glorious induction roar
to the full!
When I did the jetting with 40 mm venturis we used a 75 (Milano) Twin Spark
as a reference. The TS turned out148 BHP on the dyno - exactly as Alfa
claimed. The 74 GTV gave 157 BHP - slightly more than the claimed horsepower
for the 2.5 V6 and significantly more than the Twin Spark. Cams are 101
veloce but otherwise the engine is bog standard with the original cast iron
headers except that the head has been carefully rebuilt by me and is still
the original thickness after 100 000 miles and 2 head gaskets..
The point is that with suitable jetting, carefully done on a dyno, it is
possible to get a tractable car that is also a reasonable performer.
Les Singh
105 GTV - the last of the "real Alfas" !
-------------------------------------------------------------
From: [email protected] (Rasor Associates )
Date: Mon, 11 Mar 1996 13:52:40 -0800
Subject: Compression Testing
Over the years I have found that the first question to ask when one
presents me with compression test data is HOW DID YOU RUN THE TEST?
Please note that testing the compression in an ALFA injected car
requires one to do several things you might not think of.
1. It is best to remove the spark plugs one at a time when that
cylinder is at TDC (both valves are closed). This can be easily done by
removing the distributor cap and rotating the engine until the rotor
points to that cylinder. Also removal of the cam cover will allow one
to locate TDC for each cylinder. The reason for this is because if a
valve is open when you remove the spark plug bits of carbon will fall
and lodge between the valve and seat making your compression read
artificially low.
2. The throttle bores must be completely open to allow enough air to
enter the cylinders to get good compression. This is usually overlooked
and will make a great difference in the readings. Have someone press
the throttle pedal all the way to the floor when cranking the engine.
3. Get a reading of the initial compression during the first cranking
stroke (just approximate) This should be similar for all cylinders.
Then keep cranking for about 8 piston stokes when the pressure rise
will begin to taper off. The final compression for each cylinder should
be within 10% of the maximum reading (i.e. max compression reading 180
psi then all cylinders should be within about 18 psi of one another).
4. Measure the valve clearances if and cylinder is out of compression
specification. Chances are if a valve has low or no clearance it will
be bad and a simple valve adjustment will only postpone a valve job.
5. Run your finger over the cam lobes. A flat cam can cause low
compression and comparing the feel of the pointed end of the cam one
can easily pick out a flat cam.
6. Compression numbers will vary significantly from car to car because
of the way a person drives, fuel used, and mixture settings. The amount
of carbon in a cylinder will cause the compression to change.
7. If you get 1 low cylinder put the car back together and drive it
around the block and then run the test again. Carbon on the valves can
alter the reading. Driving the car will dislodge the carbon and the
compression will sometimes change.
8. Putting oil in the cylinder will help to identify rings vs. valves
but if a cylinder is low you still have to take the head off. Once the
head is off a simple test for valve leaks is to turn the head upside
down and with the spark plug installed and both valves closed fill the
head chamber with solvent. If the valve leaks solvent will appear in
the exhaust or intake port.
GOOD LUCK
TOM SAHINES ARA TECH HOT LINE
-------------------------------------------------------------
From: Janet <[email protected]>
Date: 12 Feb 96 17:06:29 EST
Subject: Bypass restrictor
I recently got a '80 Spider parts car that had a restrictor in its cooling
system. Since my '78 Spider was missing its restrictor, I spent some time
searching thru sources of information on how to install it and what it's
good for. Most of what I found was written by Fred Di Matteo, Charlie
Thieriot, and Carter Hendricks. Here's a summary of what I found.
The 1750 and 2000 cooling system looks something like this (heater circuit
not shown):
_______
| |==<====================<===|
| | ||
| R | /\
| a | _________ ____||____
| d | | restr | | thermo |
| i | | ictor |===<===| stat |
| a | |_______| |________|
| t | || ||
| o | \/ /\
| r | ___||___ ____||____
| | | | | |
|_____|==>====| pump |==>====| engine |
|______| |________|
Coolant flows out of the bottom of the radiator into the water pump and
into the engine block. Coolant exits the head thru the intake manifold
and then flows back thru the radiator, thru the bypass hose past the
restrictor, or both, depending on temperature.
When coolant is cold, the thermostat blocks flow thru the radiator
and allows flow only thru the bypass hose so the engine warms up faster:
_______
| |
| |
| R |
| a | _________ ____||____
| d | | restr | | thermo |
| i | | ictor |===<===| stat |
| a | |_______| |________|
| t | || ||
| o | \/ /\
| r | ___||___ ____||____
| | | | | |
|_____|==>====| pump |==>====| engine |
|______| |________|
When coolant is hot, the thermostat blocks flow thru the bypass hose
and allows flow only to the radiator for maximum cooling:
_______
| |==<====================<===|
| | ||
| R | /\
| a | _________ ____||____
| d | | restr | | thermo |
| i | | ictor | =| stat |
| a | |_______| |________|
| t | || ||
| o | \/ /\
| r | ___||___ ____||____
| | | | | |
|_____|==>====| pump |==>====| engine |
|______| |________|
At intermediate temperatures, the first diagram applies and water flows
thru both the bypass hose and thru the radiator.
For this to work, the proper thermostat must be installed. If your thermostat
doesn't have a disk at the bottom to close the bypass port, it can't function
as designed.
Finally, about the restrictor. Here's what Fred Di Matteo said about it in
an article in Velocissima from ca. '91:
"The little known restrictor in the bypass hose has a spring loaded valve
which allows more water to flow through the engine block and cylinder head
when the thermostat is fully closed in all weather and when the water temp
is below the operating range."
"The thermostat is shut tight until the water temperature increases to a
point to begin letting the coolant flow through the radiator. As that
happens. the back pressure on the bypass restrictor closes to allow more
flow through the radiator. The function of the thermostat is to control
the rate of coolant flow through the radiator so it doesn't flow so fast
it can't be cooled enough in the radiator. People who mistakenly remove
the thermostat succeed in making matters worse, not better."
"Another function of the restrictor is not only to circulate water within
the engine for quicker temperature rise, but it also gets hot water
through
the heater in the car on those cold. cold mornings. The restrictor must be
installed in the bypass hose so the valve opens in the direction of flow.
The small opening is not sufficiently large to pass all the water
necessary
when the engine is cold and the thermostat is closed."
To clarify the restrictor's installation, it goes in the bypass hose spring
side down, so the moveable disc faces the thermostat housing.
Rich Hirsch
'87 Milano
'78 Spider
'67 Duetto
------------------------------------------------------------
From: Obadiah Fayth <[email protected]>
Date: Wed, 17 Apr 1996 00:12:57 -0700 (PDT)
Subject: Coolent Ratios
Strait coolent, while probibly not harming the engine, is no better than
water in terms of cooling. The reason is because anti-freeze is like an
ingredient. When it is mixed with water the resulting solution has
improved boiling and freezing points. If you take plain water and start
adding antifreeze to it you will notice the mixture has a higher bp and a
lower fp. This trend continues until a certain point at which the bp
starts to drop and the fp starts to rise. To achieve the highest possible
boiling point and the lowest freezing point:
THE IDEAL RATIO IS 50:50
This is because in this case a complete reaction involves one molecule of
antifreeze and one molocele of water. If you were to graph the boiling
points of the mixture at different ratios you would find that the
resultant chart looks like a large inverted V. Distilled water improves
the performance of the mixture because it does not contaminate the
reaction with any other elements besides H and O. I am sure a Chem major
could explain this better but I think this is basically how it goes (what
do you expect from an engineer turned business major anyway;)
Note: this arguement does not attempt to minimize reaction between the
antifreeze mixture and the alloy engine. Their are various
types of antifreeze out there that are compatible with alloy blocks,
otherwise just buy one of those mag plugs from IAP. If you are
really worried about proper mixture levels, just buy the little Prestone kit.
- -Obie
Obadiah T. Fayth
'78 Sprint Veloce
e-mail: [email protected] | "Why build a better
snail mail: Lewis & Clark College | mousetrap when you
Campus Box 1206 | can get a bigger
Portland, OR. 97219 | cat?"
------------------------------------------------------------
From: John Burrows <[email protected]>
Date: Thu, 18 Apr 1996 07:41:59 -0700
Subject: The final word on coolant
There's a great article on the chemistry of coolant by ARA's Jack Hagarty
on the Alfa Romeo Home Page at:
http://leopard.cs.latrobe.edu.au/~baragry/AlfaRomeo/coolant.html
Cheers,
John------------------------------
From: Hirsch <[email protected]>
Date: 18 Apr 96 07:54:00 EDT
Subject: Coolant clarification
Sorry to belabor this thread, but I believe some actual data is needed.
Prestone recommends a mixture of 50% Prestone by volume (ethylene glycol plus
additives, hereafter refered to as EG) for protection down to -34 F. This is
suitable for most parts of the world. For maximum protection, Prestone
recommends 70% EG. Solutions containing more than 70% EG actually provide
less freeze protection and are not recommended. Here's the data:
Freezing pt Boiling pt
0% EG 32 F 212 F (atmospheric pressure)
50% EG -34 F 265 F (15 lb pressure cap)
70% EG -82 F 276 F (15 lb pressure cap)
100% EG 10 F 388 F (atmospheric pressure)
Freezing pt Boiling pt
0% EG 0 C 100 C (atmospheric pressure)
50% EG -37 C 129 C (15 lb pressure cap)
70% EG -63 C 136 C (15 lb pressure cap)
100% EG -11 C 198 C (atmospheric pressure)
The inhibitors in antifreeze are used up over time, so antifreeze should be
changed periodically. Alfa recommends changing coolant at least every two years.
Rich Hirsch
BTW, an azeotrope can actually boil at a higher or lower temperature than its
individual components. An ethanol/water mixture for example boils at 78.2 C vs.
78.5 C for ethanol and 100 C for water. Also, I could find no evidence that ethylene
glycol and water actually form an azeotrope (Handbook of Chem and Physics, '78).
------------------------------
From: Hirsch <[email protected]>
Date: 11 Apr 96 12:40:19 EDT
Subject: Electric fan
My '78 Spider came with AC, which, of course, I removed. Part of the AC system was a
nice 12v pusher fan originally mounted in front of the radiator and AC condensor. I
built some mounting brackets (simple "L" brackets attached to the frame) so the fan
would reside directly in front of the radiator.
To control the fan, I built a simple one or two IC control box mounted inside the car
that uses an LM355Z temp sensor. The control unit turns on a relatively high amp relay
connected to the fan.
Probably the most difficult part was mounting the temp sensor. To do this I drilled a
hole in the bottom of the radiator and soldered on a 1/4 inch compression fitting.
The temp sensor fits into a 1/4 inch copper tube sealed at one end that is installed in
the compression fitting.
This system has worked well for 10 years with no overheating. Not having the fan and shroud
really cleans up the appearance of the engine comparment and sagging engine mounts are less
of a worry (I had a friend whose fan came apart and perforated the radiator).
Rich Hirsch
editor, i Saluti, AROC St Louis, Missouri
'87 Milano
'78 Spider
'67 Duetto
------------------------------------------------------------
From: [email protected]
Date: Wed, 10 Apr 1996 21:29:34 +0000
Subject: Re: More on electric fans
(I'm sure by now those of you who couldn't care less how your
vehicles get their radiators cooled are SICK AND TIRED of all this
electric fan spew).
BGiller wrote about the lack of volume between his water pump and
radiator, and how to mount an electric fan. I have installed them in
both my Duetto and my '71 Spider (OK, so it's 99.9% the same
problem). In both instances, I put the fan in FRONT of the radiator,
so it's a "pusher" rather than a "puller". The source for my fans?
That well-known Italian parts purveyor, J.C. Whitnino. This was a
few years ago, but their inventory doesn't vary much with time.
I got a model that included a thermo-sensing switch, and like another
respondent, I used a relay to relieve the thermo micro switch from
having to deal with the inductive load (yea, I bought it from Il
Radio Shacko - wanna make something of it?). Put a diode across the
relay points to "snub" the arc when the fan switches off.
Does this really save you measurable horsepower? I don't know. It's
just more asthesticly pleasing from an engineering point of view. I
hooked up an indicator light to show when the electric fan is
operating - essentially, it only comes on when I'm stuck in traffic.
Oh, I avoided the tacky through-the-radiator mounting kit provided
with the fan, and built a bracket out of aluminum angle. Best to do
this with the engine (and of course, the radiator) out.
Good luck with it - Jay Mackro
------------------------------
------------------------------
From: "Brian Shorey" <[email protected]>
Date: Wed, 10 Apr 96 22:49:25 EST
Subject: RE: GTV Cooling Fans
>My '74 GTV threw a blade on its plastic cooling fan last week.....
>resulting in an annoying vibration ~3000 rpm. My temporary "fix" was
>to take it off.... it seems to be "revvier" now??? hmmmmm...
>Anyway, I'd like to replace it with an electric fan.... since it
>should be warming up around here soon (although snow is falling right
>now in PA) I've seen others do this, but would like your opinions.
>What size should I use? What cfm? Any manufacturers suggestions? I
>can get a Hayden locally.... others would require mail order. Also,
>what about hooking up a thermal switch. A non-adjustable one is
>available which turns the fan on at 175 F, but an adjustable one (90
>F - 210 F) is also available. Finally, what is the recommended
>mounting scheme? It comes with these cheesy plastic mounting
>"spikes"... I recall ricambi had bolts.... Any suggestions?
what's the single most cost effective performance mod for a
gtv/spider? remove the mechanical fan. it's supposed to be good for
6-8 hp.
i used a single gtv6 fan in my spider, mounted in front of the
radiator. i plan to do the same with my '71 gtv. if you don't have
air conditioning, consider getting a fan that will blow through the
front of the radiator, as opposed to sucking through the rear. there
will be a slight air flow impedance when the fan is not running, but
the extra room in the engine compartment is worth it. things like
waterpumps and belts become trivial...
for mounting, the gtv has sheet metal on either side of the radiator
(in the front). i bolted simple L shaped brackets on each side, then
bolted the fan to the brackets. the spider was a little tighter - i
bent the mounting brackets fan back and bolted them directly to the
sheet metal on either side of the radiator (again, in the front).
chrysler 2.2 liter fans are also supposed to work well, but the mounts
are real tinny. for cooling capacity, you might try looking for any
fan off any american car of 2-2.5 liters.
bs
------------------------------------------------------------
From: [email protected] (Robert A Brady)
Date: Tue, 23 Apr 1996 07:16:47 -0400
Subject: Fans, Headliners, and Window seals
In AD175, Peter Lundquist asked about electric fans for 105/115's.....
Spring finally arrived in Pennsylvania, and my GTV could no longer handle the
heat without the engine fan (it broke a couple of weeks ago, and I just
removed it). This weekend, I installed an electric fan. I purchased a
Hayden 14" unit from Pep Boys ($65.00). I looked at a lot of other sources,
and decided that the Hayden was the best option for me. It puts out
~1000cfm, was available locally, fit in the space in front of the radiator,
and the price was right. I just saw a 12" advertised in the latest Alfaowner
for $89.00. AlfaRicambi also sells a kit for about the same price. The
Hayden does not come with any provisions for turning it on (i.e. you need to
buy either a manual switch, or a thermal switch.... more on that later). The
mounting kit came with those silly plastic things that push through the
radiator to mount the fan. A picture of Ricambi's fan indicates that it
comes with bolts that do essentially the same thing. In either case, I
didn't trust this mounting scheme, and bolted it directly to the car, ahead
of the radiator. Doing this required making one bracket.
You have two options for turning the fan on, a thermal switch, or a manual
switch. I opted for the thermal switch, also a Hayden, also from Pep Boys
(~$25.00!!!!). (I've seen it for ~1/2 of that from Jeg's, a mail order hot
rod parts company.... I had no time to mail order it). Two thermal switches
were available, one that was preset to 185 F, the other adjustable from 160F
to 210F. I opted for the cheaper one (add $10.00 for adjustability). I
regret buying the preset switch since it allows my car to get up to ~200 F
(at least according to the temp gage), before the fan kicks in. ( I think
this is because the switch is mounted on the radiator, but external to the
fluid in it... convective, radiative losses keep the switch cooler than the
fluid, thus it "sees" a lower temperature than the fluid. If I were to do it
again, I'd opt for the adjustable switch....and not be so cheap. I plan to
install a manual switch in the circuit also, as well as pursue finding a
lower temperature switch. By the way, the kit comes with a relay and a fuse.
From: Hirsch <[email protected]>
Date: 25 Apr 96 13:17:07 EDT
Subject: Re: Electric cooling fans, unanswered questions
Two questions remain on replacing an energy-robbing motor-driven fan on a 4-cylinder
Alfa with an electric fan that is turned on only when needed, 1) Where to mount the
fan thermostat and 2) At what temperature should the fan thermostat be set?
WHERE TO MOUNT THE THERMOSTAT
On cars that come from the factory with an electric fan (Alfas at least),
the fan thermostat is mounted very close to the water outlet at the bottom of the
radiator. This makes good sense since you really want to control the temperature
of the coolant as it enters the engine block. The temperature of the water entering
the radiator is really unimportant. So, the fan thermostat should be mounted as close
to the radiator's outlet as possible. But surface-mounting the fan thermostat on the
metal next to the outlet seems like a poor idea, since the radiator's skin
temperature will only roughly reflect coolant temperature.It seems that the only
method of accurately measuring coolant temperature is to cut (mutilate?) the radiator
and mount the fan thermostat so the thermo sensor is in direct contact with the coolant.
AT WHAT TEMPERATURE SHOULD THE FAN THERMOSTAT BE SET?
Based on a couple of Alfa models with factory-equipped electric fans: 85 C (185 F).
Both the Alfetta and Milano have the fan thermostats set to turn on the electric
fan at 85 C. (That these values are the same is probably due more to parts
availability more than engineering design.)
COOLING DATA FOR ELECTRIC FAN EQUIPPED ALFAS
Engine thermostat Engine thermostat Electric
Model starts to open fully open fan turns on
=========== ================= ================= ============
'75 Alfetta 88 - 92 C <= 100 C 84 - 88 C (183 - 190 F)
'87 Milano 81 - 85 C 95 C 84 - 88 C (183 - 190 F)
In summary, an 85 C (185 F) fixed-temperature fan thermostat is probably fine, if one
can provide direct contact with the coolant near the radiator outlet.
Rich Hirsch
------------------------------------------------------------
>In summary, an 85 C (185 F) fixed-temperature fan thermostat is probably
fine, >if one can provide direct contact with the coolant near the radiator
outlet.
i contacted a local radiator shop about adding a thermo switch fitting to the
bottom tank of a radiator. told them i was converting to an electric fan, and
that i'd supply the switch. they said no prob, that it would cost about
$20.00. seems to me the best way to go-to do it as the manufacturers do
just my 2 liras worth
- ------------------------
From: "Brian Shorey" <[email protected]>
Date: Mon, 29 Apr 96 19:08:26 EST
Subject: Re: Electric cooling fans, unanswered questions
WHERE TO MOUNT THE THERMOSTAT
>On cars that come from the factory with an electric fan (Alfas at
>least), the fan thermostat is mounted very close to the water outlet
>at the bottom of the radiator. This makes good sense since you really
>want to control the temperature of the coolant as it enters the
>engine block. The temperature of the water entering the radiator is
>really unimportant. So, the fan thermostat should be mounted as close
>to the radiator's outlet as possible. But surface-mounting the fan
>thermostat on the metal next to the outlet seems like a poor idea,
>since the radiator's skin temperature will only roughly reflect
>coolant temperature.It seems that the only method of accurately
>measuring coolant temperature is to cut (mutilate?) the radiator
>and mount the fan thermostat so the thermo sensor is in direct
>contact with the coolant.
good point. if you look closely on a spider (and perhaps a
gtv/berlina/alfetta as well), you'll see a rounded notch taken out of
the sheet metal along the lower edge toward the back of the radiator
(the sheet metal that houses the radiator, not the radiator itself).
this notch is there to accommodate a thermostat control, so it's a
good idea to mark the radiator while in place, using this notch as a
guide.
it's where the factory intended the control to go, plus it saves you
having to make a notch of your own - if you center the thermostat
vertically in the bottom edge of the radiator, it WILL hit sheet metal
when you go to install the radiator.
bs
------------------------------
------------------------------
From: [email protected] (Robert A Brady)
Date: Wed, 10 Apr 1996 16:41:05 -0400
Subject: Tess' questions about the broken cooling fan
A while back, when I replaced the FI pump drive belt (SPICA), I removed the
fan shroud.... After putting the fan back on, i realized that I forgot to put
the shroud back on, and I couldn't figure out how to get it on without
re-removing the fan, so I left it off...... So, the fan did not impact on
the shroud, and therefore was not the cause of breakage. I don't think
anything else is near to the fan, either, so I don't think it broke from
impacting on something....?
So why did it break? Hmmmm. I noticed that all but one of the other blades
have cracks forming near their base, where they attach to the hub.....could
be fatigue over 22 years? could be the result of bending the blades to snake
my oil filters through... could be???
Anyway, I've never had problems with high temperature running (with or
without the shroud)..... but thanks for your comments/questions/concern.
I think I will go the electric fan route to ease maintenance access, and
improve horsepower.
By the way, any suggestions on manufacturer?
- -bob
'73 GTV (possible vintage racer??? winter beater???)
'74 GTV (daily driver)
------------------------------------------------------------
From: [email protected] (Simon Favre)
Date: Wed, 10 Apr 96 14:11:05 PDT
Subject: Re: GTV cooling fans
Actually, they will degrade over time. A 20 year old fan can become so
brittle from the Ozone, etc. that it will simply fly apart. I had one
do this on my Giulietta Spider. (OK, 30 years old.) My standard checkup
regimen now includes giving the fan blades a good tweak. If it snaps
off, I need a new one. ;=)
>From: "'*Tess*' Teresa A McMillan" <[email protected]>
>Date: Wed, 10 Apr 1996 06:54:05 -0700 (PDT)
>Subject: Re: GTV cooling fans
>
>This is off the topic of the question, but, does it matter to you to find
>out 'why' you broke a tine off the fan?
------------------------------------------------------------
From: TimCunningham <[email protected]>
Date: 10 Apr 96 12:00:37 EDT
Subject: re:GTV cooling fan
Bob,
I wanted to put an electric fan in front of my radiator, behind the grill,
and
found that there wasn't a Hayden fan that had the right combination of
capacity
and physical dimensions to do the job. I called Permacool (I think they have
an
800 number, send me a message if you can't find it)) and they were able to
tell
me exactly what model to use. I ordered the fan from Jeg's (big distributor,
in
the midwest somewhere).
The fan is working well now. I had to mount it very low on the radiator to
make
it fit in the space behind the grill. They tell you to mount the
thermo-switch
on your upper radiator hose, but this didn't work very well for me; the
engine
had to get really hot before the fan came on. I epoxied the thermo-switch to
the top of the big banjo bolt at the rear of the intake manifold water
passage.
Works fine. The thermo-switch trips a relay (Radio Shack) which sends power
to
the fan.
It really clears out the front of the engine compartment! By the way, there
is
a big pressed-on cylinder at the front of your water pump. It's what your
fan
used to mount to. Try to pull it off. Mine flew off under power, clanged
around and scared the crap out of me, in addition to dinging the radiator.
Tim Cunningham
------------------------------
From: [email protected] (Bruce Giller)
Date: Wed, 10 Apr 1996 12:43:22 -0500
Subject: Re: electric fan
> I recently installed an electric cooling fan on my 1969 GTV, including
> a thermostatic switch. I bought all the parts from local auto parts
> stores and am happy with the result. A whole kit complete with wiring
> harness is available from Alfa Ricambi for a bit more money.
<snip snip >
I've been looking into installing an electric fan in my '86 Spider
after I snapped off 1 blade and shortened the others at Summit Point. But
there just isn't a lot of clearance between the radiator and the water
pump; I measured it to be 3.5" (minus the fan). Most electric fans are
'taller' than this. What I'm going to look into is to off-center the fan
motor so that it won't be opposite the water pump. And they ain't
cheap....all around $100 for starters.
BTW Howard, what CFM rated fan did you get?
Bruce
Bruce
----------------------------------------------------------------------------------------------------
From: [email protected] (Luke Kowalski)
Date: Wed, 10 Apr 96 08:45 PDT
Subject: electric fan
bob writes:
>Anyway, I'd like to
>replace it with an electric fan.... since it should be warming up around
here
I have replaced the fan on my 74 Spider with the electric unit. Got it from
Alfa Ricambi (Glendale, CA) for a 100 something. Mine mounted (barely) in
front of the radiator, but in the GTV, there is probably more space in the
nose. I have seen the electric fans installed "on the inside" on a couple
of GTVs. The bolts through the radiator are a bit scary, but no leaks so
far, and the electrics are reliable. The probe (thermostat) is preset for
about 195 or so. You can probably get a generic one, but
sizing/mounting, and electrical hook-up would require some experience and
risk. And then, they claim there is a HP increase (6hp at 7K)...Makes
sense....get rid of the rotating mass.....
Good luck, luke
Luke Kowalski
Computer Aided Systems, Inc. Hayward, CA USA 510 429 2800
[email protected]@[email protected]
"ALFA- Always Looking For Another"
and now for something completely different:
"Oh, no......A Heffalump !"
From: [email protected]
Date: Tue, 9 Apr 96 18:15:53 -0700
Subject: Electric Cooling Fan for GTV
Item Subject: cc:Mail Text
I recently installed an electric cooling fan on my 1969 GTV, including
a thermostatic switch. I bought all the parts from local auto parts
stores and am happy with the result. A whole kit complete with wiring
harness is available from Alfa Ricambi for a bit more money.
A couple of cautions. There is a big difference in the balancing of
the various fans. Be sure to try out the fan before installing it.
The one I used has no disernable vibration, I passed over several
brands that tried to jump out of my hand they vibrated so much.
The standard mounting scheme is with plastic ties through the radiator
core. This always seemed like a bad idea to me, and a radiator repair
shop confirmed that they often resolder radiators damaged by such
mounting schemes.
I ended up making two brackets and attaching them to the vertical
metal in front of the radiator, a quarter inch from the radiator. Now
it is a snap to remove the radiator: no fan on the engine, no fan on
the radiator.
Howard Booster
1969 GTV
-----------------------------------------------------------
From: [email protected]
Date: Tue, 23 Apr 96 17:39:59
Subject: Of vapor separators and carpet dyes
Due to emission restrictions, the vapor separator is the only way for
the crankcase to ventilate, so if it's not working, the increased
crankcase pressure can push oil right past the gaskets, particularly
the paper gaskets on the timing cover, which are at best marginal for
the job anyway (see previous digest discussions regarding the use of
sealant on this gasket). The problem is that the timing cover gasket
is just about impossible to fix without pulling the engine, so once it
starts, it's not easy to fix.
The vapor separator, after it's been well cleaned in gasoline, is
connected to the cam cover at its top, and the other large port on the
bottom is connected to the air cleaner/filters. On this part I'm a
bit fuzzy since my car has Webers, so the exact connect points to the
air intake on the SPICA may be a little different. At the bottom of
the vapor separator there are two smaller outlets. The one that's on
the conical portion of the vapor separator is connected to the
dipstick by a long piece of tubing. Make sure that the tubing is open
and not blocked using compressed air ( don't think I'd blow though it
by mouth, petroleum pneumonia can be a real problem if you
accidentially aspirate some oil). The other, which is next to the
large port for the air return to the air intake, is connected to a
vacuum source. Without the vaccum the oil won't be pulled through the
separator screen so it can be returned to the sump via the dipstick,
and it'll eventually wind up being fed to your air intake, which gives
you the look of an Italian destroyer escort laying down a smoke screen
when you start up.:-)
>2. is the crank the same on alfetta and GTV? Or, rather, is evrything
>but the pan and the fly the same?
Definitely not. The crank and flywheel are different, the sump is
different, the oil pump is different. You can't fit an Alfetta sump in
a 105 GTV. You would have to secure a 2L Spider crank, sump, and
probably buy a new oil pump. I don't think the oil pickup is included
with new pumps, so you would have to get that too. APE has most of
these goods on tap, tho. FYI, the difference in the cranks is not
having a pilot hole for the tranny input shaft in the back of the
Alfetta crank. Some fool put the tranny in back under the trunk! ;=)
------------------------------------------------------------
From: John Stapleton <[email protected]>
Date: Thu, 21 Mar 1996 11:38:07 +1000
Subject: Reply to: 4 Cylinder motor water leak
In a recent AD, RALPHEDEL has a 4 cylinder Alfa motor with antifreeze appearing in the plug holes. This can be caused by insufficiently torqued head bolts. If you have ever seen an Alfa head cut in cross section, you can easily see how this can happen and it is normal. The first time I saw green coolant weeping out from under my head bolts, I thought it was a serious problem but it isn't. Maybe this will help RALPHEDEL.
Regards
John Stapleton