Engine Specifications

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A Short History of the Rover V8

Basic Engine Specs

The most recent change was Rover's introduction of the 'Serpentine' engine in about August 1994. This is very different at the front end of the block, with a self-adjusting belt driving a new alternator, the power steering pump and water pump. The engine also has a new oil pump and distributor drive. On TVRs, the engine also has some new plumbing which makes the offside spark plugs very difficult to get at but reduces the possiblity of inaccessible hoses springing leaks.

A note from Steve Heath:
[The engine has a] different water pump design, different fan belt and pulley arrangement using the polyvee wide single fanbelt. The first serpentine engines delivered to TVR had a slight problem with overheating. Apparently Rover changed the internal water circulation path without telling anyone and there was no bypass to allow circulation while the thermostat was closed. As a result, many TVR and Marcos owners suddenly found immense problems with the reliability. This was picked up early on and an external bypass was fitted. So all serpentine engines out there and currently used are fine.

Internet Mailing List Sep 96
Earlier 400SEs had 4.0 engines derived from the 3528cc block giving 275bhp. Sometime around 1990 the stock engine supplied by Rover became 3.9 litres, forcing a change in the engine. The result was a 4.0 engine giving 268bhp if I remember correctly. As well as the current 240bhp 4.0 litre in the Chimaera, there is an optional 4.0HC engine giving 275bhp. There was also a 4.0 litre with gas flowed heads giving 250bhp for a while.
Steve Powell

Oct 96
A footnote on engine specs. During a telephone conversation with John Eales Engineering at Coventry, JE mentioned that TVR are using the old Rover V8 engine as currently fitted in the Discovery. The Range Rovers use a newer version of the engine with more complicated engine management electronics. To service the new engine Rover supply a new diagnostic tool called Testbook which JE and Range Rover dealers have, but TVR dealers don't.

Internet Mailing List Feb 97
Today's Autocar has a 2 page article about a new 4.5-litre engine option for the Chimaera. It is a Rover derivative, not AJP, and claimed power output is marginally above the old 4.3-litre at 285 bhp (280bhp) and 310 lb/ft (305 lb/ft). It is intended to fill the gap between the current 4.0-litre and 5.0-litre engine choices, rather than replace either.
Steve Powell

Apr 97
The 4.5BV was built in 1992 to special order. Peter Wheeler would not build a 'regular' 5 litre then. He did produce one 5 litre Griffith special for a Cheshire man. It now resides in the south. It was awsome and probably too much unless you had race experience, and was nothing like the current Griff 500. It cost �45,000 in 1992, when the 4.3 was �26,000-29,000.

My own 4.5BV was one of 10-12 built. There was an article in the August 1993 Sprint about it. Others went to Shropshire, Leicester, Jersey, New Zealand and the Middle East. Team Central sold most of them. All are non-cat, put out about 310bhp at the wheels and will rev up to 6250-6500 rpm. Torque is around 328, measured on a dyno. The car is much more responsive than the 4.3 and 500. It feels much quicker, is harder to drive but is also better on a track - the ride is perfectly balanced and so is the engine, chassis and suspension. Dealers love it and so do mechanics. I paid about �2000 for the specification and it's damned good value. It goes out of tune easily and really needs servicing very 4,500 miles with constant oil changes. I run it on 4-star or super unleaded although I believe the latter causes stiction in the valves. My own car has already had a partial rebuild at only 36,000 mls as we found that the crank and bottom end was not really up to it [is anything up to the way you drive it, Steve]. The Cossie pistons and lightened flywheel are brilliant. The clutch was blown at 17,000 mls and then at 36,000, the latter not my fault [uh-huh]. We now use a Griff 500 clutch which is a pussycat compared to the first 4.5 one!

I would never sell this car. I've had 160mph on the speedo in 1996 and it was nowhere near the rev-limiter and there was a cross-wind. Most average TVR drivers would get 0-60 in 5 seconds out of it, and an experienced racer probably 4 seconds. Colin Blower set a production car lap record in it at Mallory in April '93.

There were quite a few 4.3BVs made, as well as the 4.5s.
Steve Beresford

Internet Mailing List Apr 97
TVR 134 X started life as a standard 4.0 Chimp. At the time (a year ago) I felt it was as much as I could handle as I had not driven any performance vehicle for 20 years. Several thousand miles and a couple of track days later and the 'bug' was back for good. Mole Valley said big valve, go for it. The general consensus was 4.3 as the 4.5 may push the other components a tad to far. After 1000 miles running in to say the difference is huge is almost an understatement. Cost almost �5000. Revs build very quickly, 6500 is top end.

Moved house late last year onto Team Central turf. Adrian (devil he is) takes the 'cats' off and fits what he refers to as 'sports suspension' and a roll cage. Now we really have arrived. Lower, firmer, faster and oh that exhaust. TVRs and 'cats' as Mammy said in Gone with the Wind "it just ain't fittin". Oil use is up, a litre every couple of thousand miles. And back tyres won't go much further than 10,000. Team Central have just carried out a service and the 'set up' is spot on .

I tried check the bhp & torque on a rolling road but to no avail. TVR power will not discuss the subject. All I can report is lightening response under acceleration and top speed will be explored on the Hanger Straight in May if its dry.
Bob Langley

Internet Mailing List Apr97
Browsing through some photo's I took at last years Tuscan race at Silverstone I chanced upon a nice shot of a Griff and a Chimp positioned in front of the TVR transporter. I then noticed that the Griff has Cerbera wheels with 5 stud hubs. Now correct me if I'm wrong but the pre 500 cars only had 4 stud hubs and this is definitely not a Griff 500, as the nose is the early type and a "J" reg.

So could this be the elusive Griffith 4.3BW (Big Wheels)...
Richard Branch

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Rev Limits

Internet Mailing List Sep 96
There probably isn't an electronic limiter as such - the hydraulic tappets stop opening the valves when maximum revs are reached, preventing the engine from turning any faster. I would say that around 6,000rpm would be normal, although I must confess that the last thing I am looking at on the occasions when I have hit maximum revs is the rev counter!

Without retarding the timing for lower octane fuel, it is unlikely that the engine could acheive maximum revs. In addition pre-ignition (pinking) can cause the plugs to break down at high rpm. Incorrect plug gaps can also have the same effect.

I am sure the handbook says that regular unleaded should be used in an emergency only. If it doesn't it should do. There is a big difference in octane rating between Super (98) and regular unleaded (95) fuel. The cars leave the factory set up to use Super Unleaded because this gives the highest power output, this is usually what TVR buyers are after! Unlike most mass-produced cars which have to work on any grade of fuel because they are sold in many countries, there is no automatic adjustment of the ignition timing. Unless the timing is retarded ordinary Unleaded will cause pre-ignition at large throttle openings, and prolonged pinking can damage the engine. It's not uncommon for Rover V8s to pink even on the correct grade of fuel, so it's almost guaranteed to happen on a lower grade (even if you can't hear it over the din from the exhaust).

There's no reason why you can't adjust the timing if you want to run the car on ordinary unleaded, you will see a loss of power in the order of 3-5% but in a car with a high power to weight ratio it probably won't matter too much. It's a personal choice which everyone will have a different opinion about, but if the savings seem attractive you should have the timing altered ASAP.
Steve Powell

Internet Mailing List Sep 96
After several phone calls to TVR and Team Central, I think I have an official answer. It seems that the later ECUs for the V8S - i.e. those with a cat - are programmed to limit at 5600 rpm and not at 6000+. The reason was that the addition of the cat required different engine mapping which moved the maximum power and torque slightly down the rev curve (the same thing happened with the S3 and S3C). As a result, my car is only doing what it was set up to do and thus has nothing wrong with it . In losing a few hundred revs, it gains a lot more lower down grunt, which for a road car is fine by me.

The problem is nothing to do with the plain unleaded although I will try with Super unleaded with the next tank to see if there is any difference. What is confusing is that the owner's manual indicates that the peak power is at 5750 and that the red line is at 6000/6250. This was probably based on the first no-cat cars that TVR produced. The published test reports for the V8S also support these figures. I also would not be surprised if TVR disabled the limiter on the test car! While on the topic of V8S revs, I found this is the Sprint archives.

The engine management system uses several sensors to determine idle speed (amongst other things) under all conditions. For whatever reason, choice and location of sensors, inability to spend sufficient time and effort for such a relative minute production, the only time the ECU always gets it right is under 'ideal' conditions. The practical solution is quite simple. 1-2 mls after start-up don't do anything other than turn the ignition off for 2 seconds and back on leaving the car in gear with the clutch engaged. This makes the 'little chips' in the ECU forget any data that they had and it thinks that the engine is now at optimum conditions. It works at treat on my V8'S'. It burbles on idle like something massive from Detroit, howls like an F1 above 3,500 rpm, cracks and flames out the back in between upward changes at high revs and masses of wellie, pops and bangs on the overrun, and is quiet and unobtrusive at 85mph (keep your licence) motorway cruise.

Has anyone tried it? Does it work? I tried it on mine and it didn't make any difference - it makes these sounds anyway!
Steve Heath

Internet Mailing List Sep 96
[TVR's explanation of different rev limits] is odd, because that is not the case with cat-equipped Griffiths and Chimaeras. The 4.0 Chimaera shares the same engine as the V8S, and revs to 6,000 rpm according to road tests. My 4.3 Chimaera did too, so it's still a bit mysterious why the V8S is different. Perhaps the cat installation is less efficient due to space limitiations.
Steve Powell

Internet Mailing List Sep 96
I have just received a phone call from TVR who say that they have been doing some further research and there were two ECU chips developed for the 4 litre V8S/Chimaera engine: one that limits at 5600 and another that goes up to 6250. The choice appears to be arbitary i.e. on a car to car basis. This would explain the difference in rev limits that Steve Powell was talking about. They did not immediately know the differences between the two in terms of peak power and torque and whether it was possible to change the chip to give a higher rev limit, but they have my details and are going to come back to me with this information. They also said that problems with fuel grade appear much lower at about 4-4500 rpm and that both chip versions are capable of running unleaded unmodified but with a greater risk of pinking.

It is possible that the 5600 chip is more tolerant of unleaded fuel and was used on cars destined for export. My car spent its first three years in Guernsey where I suspect that super unleaded is unavailable and this may explain why it was fitted with the 5600 chip. This is only a guess mind you. If this is true, it would also explain why it appears to run OK on regular unleaded.
Steve Heath

Internet Mailing List Sep 96
I think I've worked it out! While digging into my collection of TVR trivia, I've discovered that there were two 4 litre V8 engines in use in the early 90's with different characteristics.

Bore, stroke and capacity were the same. Engine A is the one spec'd originally for the V8S. Engine B is the one spec'd for the Chimaera in 1993 and for the Griffith.

I suspect that the two ECUs were for these two slightly different engines, with the 6250 fitted to engine A and the 5600 ECU fitted to engine B. The adjustment in rev limit compliments the change in peak power and torque. If this is the case, then it is unlikely that the ECUs are interchangeable. However, engine B with it's lower compression ratio is possibly less susceptible to pinking. Engine B also had a softer cam than engine A to "improve the lower down torque for road use".

I'm wondering with the changeover to the Chimaera in 1993, that some engine Bs found their way into the last few V8S that they made. This would definitely explain my car. I'll have to wait and see what TVR say.
Steve Heath

Internet Mailing List Sep 96
I've just had it confirmed.

Yes - I have the Chimera spec 4.0 V8 in my V8S. It also matches the Chim wheels!

Yes - It does and should cut at 5600 (peak power is at 5250 rpm).

Yes - It does have more lower down torque than the pre-cat V8S engine (almost full torque at just 2000 rpm)

No - you can't change the ECU (well you can but you have to convert the engine as well!).

Yes - you can get the engine detuned to run on plain unleaded (just as Steve Powell said). Apparently Nigel Mansell SportsCars (as was) used to do this as a matter of course because there is virtually no Super Unleaded in Dorset. Sprint's editor Ralph Dodds ran his after the mod with no problems.
Steve Heath

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