4ac

[rich_86]

thinking of keeping one of my hachis 4ac (used for tight to medium hill runs) and jus wondering....

how much can i shave the head for decent compression????

what size and brand twin carbs to run???

ideal ratio for diff???

short or long primarys on extractors???

4-2-1 or 4-1???

thanks in advance peoples

[Gilly]

i wouldn't spend any cash on the engine

buy diff gears though, like 4.7's in a t series

that would be the best bang for buck mod and you can easily transfer it to another car when you realise 4AC's are, well you know...

:lol:

[rich_86]

ha ha funny i no its not common but already have 2 4age 86s and would like to see how fast a 4ac 86 can go before i give it a 4age from my current daily

[Jonny Rochester]

As for compression and valve clearance, measure it yourself. No one here is going to be 100% confident in knowing how much to take off. Do calculations yourself.

4-2-1 is best for midrange torque. 4-1 is best for max power at high revs.

Use any carby you want, something with a bigger throttle of course. You will have to make the manifold.

[rich_86]

any carbies designed for 4ac straight off the shelf????

[meadan]

You can get a single weber to fit easily on the stock manifold with an adapter.
Also ive seen a few twin carb manifolds on US sites, but they probably cost quite a bit.

I think the shop is paradise racing in the US which has heaps of 4ac parts..

[Driftspec]

<div class='quotetop'>QUOTE (Gilly @ Feb 17 2008, 09:06 PM) <{POST_SNAPBACK}> (index.php?act=findpost&pid=487836)</div>
that would be the best bang for buck mod and you can easily transfer it to another car when you realise 4AC's are, well you know...

:lol:[/b]

Oi! :P

Single 34/32 Webers are a common mod, but I haven't seen anyone do a twin Weber setup, so I have no idea on how easy it is to do, not to mention the cost.

Extractors I've thought about, but the only problem is that they aren't off the shelf parts, so odds are the exhaust shop would have to be fabricating it up for you.

Next thing to think of would be cams, but again the problem is off-the-shelf availability.... there isn't much available :(

[rich_86]

anyone no what size the exhaust ports are??? and would say fwd extractors fit with a little cut and weld jus before the flange to get it going the right way???