Full Sik exhaust, bro...

[Motographics]

... an' it's gotta cannon!

I recall Glenn saying at the Open Day that he felt the 2" exhaust on his car was too big (I think).

In my Corolla Cup car we had 1 3/4" (I think) with no Cat and it gave much crisper throttle response and a little bit better bottom end I suspect, but there was a noticable loss at the top end. In hindsight, for that car this turned out to be the opposite of what we needed.

What is conventional wisdom on the best spec?

Cheers

[Crazy Dave]

I think Glenn said a 2.5 inch was too big and that 2.25 or 2 inch would be more preferred to keep some pressure in there.

[Motographics]

Yeah 2 1/2" sounds way big.

I will consult the exhaust guru - Craig Stallard at Quikfit Gladesville, former NSW Rally Champion - and report back the results.

We have had rally exhausts from Craig before and they are excellent (:confused: pun?). Apart from whatever performance increase may be achieved, he builds them high and close to the floor and plates the areas that may be damaged in rally use and uses sprung slip joints and extra hangers etc etc. I can attest to the extra durability.

End gratuitous plug:)

[Glenn]

Yep. Mine is 2.5" and is too big (was cheap though and sounds good....and coming from the Suzuki I don't miss the mid range). I reckon a 2" would be great, maybe 2.25" if the press bends are tight.

The Stallards are the way to go!

Cheers

Glenn

[Motographics]

OK, I spoke to Craig a week or so ago and he recommends a 1 3/4" or 2" system.

His full system with plating etc. as described earlier would be about $800. Sounds a lot up front but is worth it for the lack or repair or maintenance down the track.

He also suggested using the 4-2-1 manifold from the DOHC to replace the 4-1 on the SOHC but this would not be legal would it? Only free from first junction back?

BTW he is at Carline Gladesville, not Quikfit.

[Crazy Dave]

From reading the regs, I would be inclined to say that you can put the manifold from the twin cam onto it as long as it doesn't get nay machining at all. You are not allowed to match the ports or anything like that. If it bolts straight up to it then as it is a standard excel X3 part then I would say good to go. Do you know if it can be fitted without any machine work.