From memory playing with mates 6cyl Holden with tripple 2in su's on his torrie they camE STD with .110" mains in em.

Might be worth sacrifing a rich idle to keep it happy up top.

 

Because of the big cam in mine and the 25ish deg of advance at idle if I get a perfect lambda at idle it runs real hot. But that's the joy of a locked dizzy.

 

Stu.

I know the Drawthru setup in KETURBO25's KE25 it seems to run rich down low to keep it happy up on boost. Thats running a 42dcoe.

I've got a pair of Commodore oxy sensors in mine, VT I think, one reading each SU.

 

How about making a needle out of a suitable nail, so it gives you an idle and 2 statons or so. It would only need to stick out 10 or 12mm, then no needle at all. That would tell you if the jet will ever flow enough fuel.

 

With 10deg it shouldn't be pre-ignition causing the knocking- how about octane booster?? Toss in some toluol or xylene to get it running and tuned.

Wouldn't locking the dizzy at 10 degrees make things difficult as well? Especially if you're trying to get it to rev.

I'd agree Snot, you need more advance the more revs you use, but I assume the guy who locked it knew what he was doing. With giant compression at low revs it must burn pretty fast, but if its knocking already there is no use in giving it 20deg at 2000rpm.

 

Maybe its dieseling! The first compression-ignition rolla!!

snot35, i had the dizzy locked when the car was still naturally aspirated so i could check that it would still function correctly. didnt seem to make all that much difference to the way the car drove, just lost a bit of top end.

 

i picked up a 40 dcoe weber carby the other day so it looks like i'll be modifying my pipe work soon to fit that.

 

the only reason I'm going that wasy is i know that i can tune it, or i can take it somwhere to get tuned. no body wants to touch the su because they say its too hard to get right. i would keep the su if i wasnt having so many issues with the damn thing.

 

i have a pretty good grasp on how to tune webers and i can buy jets for them at the local mechanic so should be easier to get going.

 

 

thanks to all that help out with some great ideas

 

cheers

Matthew

Any news on this?

um, i have the weber, rebuilt it the other day, going in to work tommorow to make up new pipework/plenum to take the dcoe in place of the su.

 

been a bit busy traveling with work so havent had much time to play. ill post up some pics when I'm done

Cheers that would be great!