<VV> 64 Engine - Performance Wanted

[Bruce Schug]

On Mar 29, 2007, at 9:48 AM, D. Barry Ellison wrote:

> Again, this 64 engine is a dog.  Symptom is that when it's cold, it 
> runs pretty good.  As soon as it warms up, nothing - won't get out of 
> it's own way, literally has a hard time going up my SC rolling hills.
>
> Other Specs and things I've checked: idles pretty good, cranks pretty 
> good, vacuum advance works and holds, MSD ignition with points as the 
> trigger, distributor weights working freely and installed correctly, 
> distributor plate good, timing set with a light, 92 octane and zero 
> pinging, zero run-on, new wires, ULTRA plugs (prob not 5k miles on 
> them - came from the 140 engine), rebuilt carbs that seem to be 
> working okay (noticed a drilled hole in one of them yesterday which is 
> now plugged, just above the lower nut - water injection?), choke 
> pulloffs set and operate properly, choke's pull off properly.
>
> Best we can come up with: she needs bigger jets...it's got 50's.  
> (warms up, chokes open, more air, not enough fuel)  I've got 53's and 
> 55's in my pocket.  I'll be autocrossing this weekend and she's a 
> daily driver for the short term after that. Which would you use and 
> why?  Will it help?  Is 55 too big?  Don't want to do it but once, but 
> will do it twice if necessary.  Logic dictates I put in the 55's and 
> if it fails, I should put in the 53's.
>
>

Barry,

Could be a coil. This is the classic answer to a "runs-good-when-cold, 
dies-when-it-gets-hot" problem. Are you using the same coil you used 
with the 140? If so, it probably didn't go bad just as you changed 
engines. If it's a different coil, try the one you used with the 140 
which must have been a known good coil.

I agree with your suspicion of incorrect jetting. If it runs good when 
cold with the chokes on, it sounds like it's leaning out when warm. 
However, my experience is that the engine will run pretty well even 
when very lean. You might pick up a hesitation upon accelerating but at 
least when cruising or under steady power, I bet you could run 46's and 
be okay - not recommended though.

You're sure the ignition is okay - the advance and everything? You 
might try running just on the coil, that is, bypassing the MSD. One 
thing I know for sure - an MSD requires VERY GOOD plug wires. When I 
first ran an MSD I had an old MSD-5. It was fine then started running 
poorly. I checked everything, including the plug wires. I was sure it 
was faulty and sent it back. It tested fine - they returned it. I 
installed a new set of Seth's wires and the problem went away.

Hope it's the coil.

Bruce







Bruce W. Schug
bwschug at charter.net