Brakes
Brake Fluid
Chimaera Disks & Pads
Pad and Disk Upgrades
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Brake Fluid
Internet Mailing List Sep 96
For track use of your car, it's a good idea to renew the brake
fluid before every track event. There are plenty of good brake
fluids out there, but what's most important is that the fluid
is not contaminated with water and solid particulates . . . If
the brake fluid colour in your reservoir is much different, usually
darker, than the colour that it came out of the container, then
it certainly should be changed before going out on the track.
If the car isn't used on the track, changing the fluid once a
year is a good maintenance practice. The signal that your brake
fluid is boiling is a pedal that travels easily to the floor without
an attendant decrease in the car's rate of travel.
Steven Jackson
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Chimaera Disks & Pads
Letter Nov 97
. . . I had great difficulties in finding the right rear brake
disks [for my late 1994 Chimaera]. In my TVR Owners Handbook
on page 42 it says:' with 10.7" diameter rear discs.' So
I ordered that size of discs off a Ford Sierra Cosworth. When
I tried to mount them it showed that the size of the disc was
too large. The real size of my rear disc was 251 mm that is about
9.9". The disc I needed is of an early type Siera Cosworth.
For the brake lining I used Lucas/Girling pads, no. GDB472 (Holland
coding?). The discs I ordered in the end are coming from QH
(no.BDC3583) as they where able to deliver them immediately.
I hope they don't fall off!
Arjen Wolters
Letter Aug 98
I took a pair of my front pads and showed them to a technician at my local dealer. He reckoned they were not original and advised me to fit a new set.
The brakes fitted to my age of car are Ford XR3i/Cosworth so he suggested I went to a Ford dealer and saved myself some money. He showed me a set from the stores and they were boxed Motorcraft, i.e. straight from Ford.
I did this and the brakes are now 100% better. The pads cost �15 compared to �50 from a TVR dealer.
Prebble, Richard
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Pad and Disk Upgrades
Sep 96
Post-1994 models have larger front disks and calipers. Several
owners have improved braking by fitting TAR.OX grooved front disks
and Mintex 1144 pads.
Apr 97
[From telephone conversation with Raymond Chang, who has a 1994 Griff 500]
He has tracked down the source of his car's disks and calipers:
the front assembly is from an Escort RS Turbo Mk 2, and the rear
from an Escort Cosworth 4x4. Raymond doesn't rate TAR.OX disks
much. He is now using grooved and ventilated disks from Diamond
Motor Sport, which he says are much better than TAR.OX and cost
about £110 a pair. Brembos are good but incredibly expensive.
He has fitted the factory suspension sports pack and apart from
a bit more bump-stear he says it's excellent.
Internet mailing List Feb 98
Have you had, or do you know of anyone who has upgraded griffith 4.3 brakes, specifically the disc's to grooved or cross drilled
items? Most TVR dealers are recommeding upgrading to griffith 500 brakes, but this is proving a little too
expensive (£500-£1200) not fitted!
Adrian Wallbridge
Internet Mailing List Feb 98
I don't know about 4.3 griff brakes, but I suspect (and no doubt someone on the list will be able to confirm or deny)
they are the same as the 4.0L Chimaera brakes. I changed mine for TAROX pads & disks (grooved) after experiencing a bit of
fade on the track. I have to emphasize though, never had a problem on the road.
I did one session at brands with the new setup & found them excellent. Fernhurst (as seems normal on this list) did the mod.
David Leeming
Internet mailing List Feb 98
I was looking at the Demon Tweaks catalogue last night and I remember that AP Racing calipers (as used for the Cerbie) are
£1300 a pair and Brembo disks (group N - not grooved) were about £70 a pair.
This was for Ford Escort Cossie hubs - as used on the Griff? Seems like someone is adding on huge amounts of labour, surely
it can't be more than a couple of hours to replace disks and calipers.
If you just want Tar-Ox discs and a set of fast-road pads it shouldn't set you back more than a couple of hundred quid. Changing a pair
of disks really is a 30 minute job.
Andrew Guy
Internet mailing List Feb 98
. . . The brake balance is extremely important with these cars. Too much bias to the front and the back will lighten up and step out. This one of the
reasons that the 500 has bigger rear disks than the front. The front stops but the back doesn't and tries to get in front. Result is one
spinning car. If you want to simulate this, brake hard when going over a bump as the rear goes light. On second thoughts don't. Take it from me,
the car will spin quicker than that. (This is what I did wrong at Castle Coombe, dear readers). The bias is about equal with a slight bias to the
rear brakes. This means that any changes should be done to both front and rear to maintain the correct balance.
Brake balance problems are only normally seen when the braking is extreme... like on track days and usually when you need it the most.
Braking performance is also greatly affected by other factors. My sprinting spec 390SE brakes are certainly enhanced due to the mods that I
have made... The strange thing is that apart from changing to DOT5.1, the brakes are exactly the same. The changes to sticky Yokohama tyres,
increasing the stiffness of the front shocks and adjusting the brake pedal height so that I could get more pressure on it have transformed the
braking performance of the car. So much so, that I have dropped the idea of renewing the disks and pads as I can lock all four wheels almost at
will now! The stopping power was there but these other factors prevented me from realising it. Again, it is worth checking these items as well.
The [Griffith 4.3] brakes are based on Ford Sierra Cosworth/Escort Cosworth etc. I
stress the word based. Looking at the way the disks were drilled for 5 stud hubs as well as four, I suspect that the disks may be specials
anyway. Some of the diameter sizes do not appear to match those cars. The only way to actually confirm which disk will fit is to take an original
and physically match it to its replacement. Measuring its diameter and quoting the offset is a good start but a physical comparison before
fitting is absolutely essential. You could end up fitting disks that would fit but are smaller than the originals. Not a good idea...
One final point, some companies quote disk prices for a single disk and not as a pair as would be expected. Always ask to prevent getting a hefty
shock.
Steve Heath
Internet Mailing List May 98
I have just been quoted £1,600.00 + VAT by a TVR dealer to upgrade front and rear brakes on my K-reg Griffith! The replacement parts to be based on Grifith 500 units. Originally, I asked for a front brake conversion, but the factory advised against this as the front/rear brake
bias would be adversely affected. So I declined, and instead have asked for the existing brakes to be attended to, new pads, fluid, cleaned disks, etc.
Now I know from mails past that some of you have had brake conversions, so any feedback would be appreciated. Incidentally, I mentioned having Tar-Ox
disks and this elicited a sharp intake of breath (prone to buckling, cracking, etc.).
What I'm after is just a bit more bite at the front-end.
Dave Peck
Internet Mailing List May 98
Call Dave Wallis at Tower View Race Services. He has a complete range of brake upgrades for most TVRs, ranging from simple disks and pads
to four pot calipers etc. They are either Tar-Ox or Brembo - I can't remember! Ted Riddick had Tar-Ox grooved disks added to his Chim 500
front brakes and said that they definitely had more bite and less fade so that may be a good route. It might even be worth considering doing both
ends in the interest of balance. The comments about buckling and cracking are interesting. The standard disks will do this if they are abused. If
you overheat the brakes, there is a great risk of buckling and cracking through hot spots with any disk.
Don't go for the race pads otherwise you will find that they will require several applications before the pads get warm and work. Fast road are
probably as far as you should go if the car is used on the road. The last thing you want is to get out from the garage and find that you can't stop.
Steve Heath
Internet Mailing List May 98
Whilst you may think you have Tar-Ox, the previous distributor had them copied elsewhere and sold them in Tar-Ox boxes with variable quality. Tar-Ox
got wind of this, and now have a new UK agent and a bunch of lawyers. We deal with the new agent. TVR isn't listed in the
catalogue, but if you let me know the Ford equivilent I'll look up prices.
Andrew Cliffe
Omicron
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