Crane HI6 install, and still some stumbling

[JShadzi at aol.com]

Hey Jimmy,

On a related note, took my car for a spin today for the first time in a while (took about a month of downtime to put the IC in in my spare time).  The best words to describe a flowed out 80tq MC motor with EFI?  Huba, huba.  Anyhoo, I'll be flogging her at Buttonwillow Raceway on Monday, if anyone's in the area come out and say hi.

Ok, Jim, one thing I've been thinking all this time, is are you running street gas, like 90-something?  I haven't been able to really run more than 15psi on street gas, granted CA gas is the worst in the nation, but I think you're really pushing the limits of power on street gas.  At 15psi I estimate you're making 300 crank, at 20 I'd say closer to 350+ crank, I suppose you can track the pinging with the APC, but have you tried like a 10% tank of Toluene or a half tank of 100 oct?  That would be an interesting test.  Another thing, have you done a pressure test on your induction side up to 20psi?  Just curious, might be nice knowing you don't have any leaks at that boost level.

Also, have you tried some more advance in that range?  Typically a motor is most prone to detonation at its torque peak. As you can see when I dynoed my car at 15psi -http://www.80tq.com/images/Dyno1.jpg , the torque peak is right around 4k rpm, but its ramping up right at 3500.  That range between 3500 and 4k is probably the most critical range in your ignition programming.  Once you're past this range you can actually advance timing all the way up to redline in some cases.

So, I'm sure you have, but what have been the results of advancing or retarding timing in this range?  IME, when you're too retarded, the motor is making a lot of noise with no acceleration.  Too much and its a pinging barrage.  With the WI you should be able to run some pretty good advance.  Anyway, just dumping out some thoughts, hope they help.

BTW, Coppola Red Zin is really good.

Javad


>
> Hey Everyone,
>
> Thanks for you brainstorms, I moved the reference line
> to pre TB, and I'm still getting the same results at
> 20 psi.  With the regulator unhooked the boost is
> solid, but I only can get 11 psi at 3500 rpms, so I
> didn't think it's a very good test.  This is all
> without the WI on just to rule it out.  I'd really
> like to try a huge WG spring just to see what happens,
> but I don't have one, yet.  It's possible I don't have
> enough ign. advance in that area, but at 3500 rpms and
> 20 psi it shouldn't take much at all to get things
> going.  I'll carefully play with it tomorrow.
>
> Thanks,
>