> IMHO,
> Your time would be better spent (performance wise) learning to tune
> SUs. -Correct neetle profile
> Phil
> SPL311 FJ20 EFI
> SRL311 FJ20 Turbo project
I appreciate the advice Phil, but actually the SU's are soon to be history,
I've built an EFI manifold to be installed this spring.
The distributor is also removed, I am running on a '92 Escort DIS system
with programmable advance.
>as I recall the general chatter in the past has been that >Nissan actually
>got the stock manifold pretty
>close to right - that many of the aftermarket headers >actually decrease
>performance. YMMV with a well->designed header, of course.
>-- John
I have been hearing that for twenty years. AND from my experience I believe
it to be true (for a stock engine). However, the stock manifold, and the
aftermarket headers were designed some 35 - 40 years ago! I have not ever
seen a different header.
I believe that technology and the understanding of gas flow has changed a
little since then. Take a look at some of the newer 4cyl exhaust manifolds
(FJ20, SR20...), I'll bet they are all of the 4-2-1 style.
Yes, I am trying to upset the status quo. I think we have dropped the ball
on this one. Expense being the big reason? Not enough turnover to recover
the expense of development for a quality piece with unkown benefits?
Projected sale price deemed too high for this market? Or just never thought
about it?
This design would benefit both R and U engines. I can't see a good quality
4-2-1 header being more expensive than the stock manifold if made in
quantity, with some real performance benefits. I guess nobody has done any
development on these engines since the BRE days and I find it somewhat
frustrating.
Why?
To quote a freind of mine: "You will never turn a pig into a racehorse. But,
If you beat it hard and long enough, you'll have a really fast pig."
No offence intended, but.... I want a faster pig!! :-)
Cheers
Daryl
'66 1600 Work in Progress
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