New TVR V8 engine?

[Qualia]

I met a guy in the pub last night who claimed that TVR are developing a new V8 engine. He said he was at the factory in Blackpool a few weeks ago and saw it on test. Only other piece of information he had was that it has a plain (?) crankshaft and sounds fantastic.
Now, what do you make of this? Could he be talking about the AJP8 engine? I don't know what kind of crankshaft the AJP8 has, I'm sure some of you will know. Maybe we'll see the Tamora coupe with a V8 instead of the Speed Six at Birmingham?
Any thoughts? And, by the way, the guy was on his second pint when he told me - so not just drunken talk....

Andy

[Ston]

The AJP8 has a flat plane crank.

Saying 'it has a normal crank' doesn't really mean much, as a flat plane is normal for a sports car.

I think TVR are pushing the speed 6, as it is the engine in the GT cars and also the engine that completed the Spa 24.

In terms of power they can pretty much produce the same. The sp6 having 4 valves per cylinder probably neutralises the effect of having 2 extra cylinders. Accept the sp6 produces the power higher up the rev range.

The 4.4 Sp6 produces 440 TVR BHP
while the 4.5 AJP8 Red Rose produces 450 TVR BHP.

The speed 6 tends to be more accurate though on the stated power figures

[squirrelz]

The 4.5 Red Rose is sort of new, isn't it?

[Ston]

nope. It is 2 years old. The first cars with it are avaliable on a Y plate.

Even so the engine is still the same. It is an AJP8. The Red Rose conversion just increases the compression of the engine, It also has an ECU map for higher octane fuel.

[christof]

Yep, the rumour is right.

TVR is developing a racing engine for Shortys Mosler race car

Christof

[andytk]

Ah but the question is what type of crank?

Is there any truth in the rumour of a regular crank (as opposed to a flat plane)

Flat plane would be better for racing but a normal crank would make the engine sound like a Griffith or a Chimeara. Hmmmmm. That would sound nice.

If its a totaly new engine then this could be possible but I doubt TVR have the resources for that just now. More likely its just a development of the current AJP8.

Care to shed any light Christof???

Andy

[christof]

I'm kidding mate

Christof

[andytk]

oh

Doh!

:feelslikeagulliblefool:

Andy

[Qualia]

Can anybody explain this crank business to me? I think I have a vague idea, it's got something to do with the shape of the crankshaft and the way the pistons are attached to it, right? So, what does a flat plane crank look like as opposed to a "normal" one? Why is this better for sports cars? Is this only relevant to V-shaped engine layouts? Finally, what has my S3 got?

So far I have been quite content in the knowledge that my S3 has got a crankshaft there somewhere and I hope that for years to come there is no need to actually verify its existence, but my curiosity has been raised...

[dannylt]

Search for another thread on the Rover V8 section... but basically, it's called flat plane because the crank's throws are in a single plane, i.e. you can put it flat on the floor without anything sticking out. Practically, this means the engine essentially runs as two four cylinder engines on a common crank. This is good for power/racing because 4 cylinder engines are nice and easy to tune inlets and especially exhausts for - nice simple 4 into 2 into 1 (like on Cerbie) or 4 into 1 (like on racing tuscan).

A traditional V8 like the Rover, Chevy, Ford etc. has throws in 3 dimensions, and has a much more even and balanced firing pattern, hence nice and smooth with that lovely rumbly note. Almost impossible to design a decent scavenging exhaust for though.

danny

[f402mlr]

dannylt said: Almost impossible to design a decent scavenging exhaust for though.

Traditional V8 has the cranks at 90 degrees to each other and the Vee of the blocks is at 90 degrees, so the firing order is then regularly spaced. To balance the exhaust you'd need to join the outer pair of one bank and the inner pair of the other bank. (times two!)This was done on some F1/GP cars in the 60's! -
with the resulting pipe work mess on top of the engine, the inlet (PI or multi carb) being on the outside of the the Vee. The traditional USA V8 used a single carb (say Holly) so had all the inlets on the inside of the Vee. To save pipe work the exhaust from one bank were commoned, but exhaust pulses in a bank are un even, this gives that V8 burble as the sound comes from each side in pulses. ( Look at the firing order for one bank 1,-,-,3,-,5,7,- with -,8,4,-,6,-,-,2 in the other pipe. (1-4-6-7 would be balanced!))

The S3 V6 is nicely balanced with a 60degrees Vee and 120 degrees crank throws and joining the exhaust on one side