Centre exit exhaust on an 850?

[coopertim]

Morning all

I've decided to keep DPU at 850 but add a 295 head and twin carbs with a different cam. I bought a Works style centre exit exhaust to fit on VFF last year but obviously never got it fitted. Would this be ok to use on the new car?

Cheers Tim

[Frogeye61]

I had an 850 with 295 head and twin carbs a number of years ago. Lovely car, screamer. Of course you know you have to skim the head quite a bit, 2.5mm or more. I always liked the center exhaust.

[mk1]

I suspect a Works type centre exit will not have enough back pressure for an 850.

But I suppose there is no harm in giving it a try, it certainly won't do any harm.

[andy1071]

It's not back-pressure you want with a 4-stroke engine.
It's diameter and length that are important.

If the manifold and first part of the system is around the right size, then I wouldn't think the centre exhaust would be a problem.

Noise is another matter though....

[mk1]

It's diameter and length that are important. Tee Hee

You are of course right Andy, but having an exhaust that is "too free flowing" on a small capacity mildly tuned car can have a negative effect on performance. Particularly low down torque.

[minitravellerman]

When I first built the '62 I fitted a small bore centre exit. The original exhaust was rotten just after the kink at the bottom of the manifold, so cut off the rot and made a new centre pipe linked to a Ford Dexta exhaust



It worked well but was too noisy for the image of the car so only lasted a matter of months before replacing with a new standard zaust. Would be good on a more racy image (I still have it by the way )

[rich@minispares.com]

is that marge simpson taking the photo............

[mk1]

Why, I think it is

[rich@minispares.com]

Why, I think it is

[GraemeC]

Somebody's quiet at work today!

[minitravellerman]

Why, I think it is

lol - this is why I should make sure I use the zoom and stay out of the photos!!