blown sbc fuel problems?

here's thew car...355 6-71 alky enderle bugcatcher -1 pump #50 nozzels .070 main, 10.5:1 .570 roller, 15% over, 15psi boost.

The problem: egt from cylinder to clyinder vary by more than 300* at idle, get hotter as you go to the back of the motor. Car just breaks up when a load is put on it.

Mallory hyfire ignition with a Mallory coil, plugs gapped at .022. Timing is locked at 30*

Any ideas??

Thanks

Brian

 

SBC probs

Hi what does your pump flow? Mine flows 6.5 @ 4000 I run 56 nozzles 50 main, egts are only 700-900 at idle, I am running an 8-71 @ 8% maybe you have a BV problem how much does the BV leak? What do the plugs look like?

 

sbc egt temps

Hi Brian

I ran a freight train car here in NZ. 2 x 355 sbc, 6-71 @ 7% over, enderle hats,6.5 gal pumps,50 hat nozzles and mag at 30deg. We had same problem as you with back cylinders which we could only put down to the manifold we were running.
What i did was to introduce a port nozzle line into the problem ports and I used a small nitrous down nozzle with the flexible lines which the sprint cars use.I thread these lines directly into the distibution block. We could not stop #7 & #5 from melting pistons until the added fuel lines. Also #6 never melted pistons but was always hotter so this cylinder got an extra line. I dont know what manifold you use but there is a little tricky machining to accomodate the lines between the blower and manifold.To give you some idea we ended up with .022" - .026" nitrous jets in these lines which indicates how lean these were in the first place.Another problem may be your spark.We ran vertex mags(old ones) which were only a couple of amps each.These had a mallory conversion which uped the anti to 6.5 amps.The car came alive! The mags coupled with the fuel changes took the car from 7.0s @ 185 to 6.65 @ 210. I can send you photos of the manifolds if you want them.Email me mark@rpmtoolanddie.com. Hope this helps.

Mark

 

Thanks

Thanks for the replies,

I am going to get the fuel system flowed to make sure the BV and pump is not a problem. The motor also seems to run hot, which leads me to believe its a fuel problem. I'll keep you posted.

Thanks agian,

Brian

 

Brian,
I ran the exact same deal in a nostalgia funny car last year. Enderle 80A pump (7.1 gpm), 46 hat nozzles and most of the time 95-105 main pill (hat nozzles only)
Car ran great! 7.76@170 (2100# car) ignition was MSD 7AL with the HVC coil. A traditional coil would not work for me. PM me if you want complete info on the combo.

I'm new at this, but if memory serves me correct, higher EGT's equal RICH condition. I think Mike Canter spoke of this in one of his articles, maybe he can chime in here and clarify.....
Keith

 

Kinsler

Spoke with kinsler today...they need a couple weeks to flow my whole system...

A freind stopped over with another pump, going to try that first. Can't really see anything going wrong in a BV anyway.

Brian

 

Put the new pump on...sounds better...any idea what the pump pressure should be at around 4500 rpm's? It's a -1.

Thanks

Brian