Author Topic: At a loss - engine stalls under load  (Read 2462 times)

Kelley W King

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Re: At a loss - engine stalls under load
« Reply #30 on: July 12, 2022, 09:40:27 PM »
To me it sounds like you have a vacuum leak. Hard to hear with a BB at 1,000 RPM. I think you might have caused it during your carb change. Does the different carb have a port not used?
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R68GTO

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Re: At a loss - engine stalls under load
« Reply #31 on: July 13, 2022, 12:36:43 AM »
primaries are bone dry at idle.  With old carb that Eric worked on, I had 14.5" vacuum.  New carb is 5 inches of vacuum.  I haven't reached out to Eric yet but probably will once I get done with Camaro Nationals and Supercar reunion.
KK, I'll double-check on the unused port thing in the morning.
1969 427 COPO Camaro Lemans Blue/Black, M22 4 speed, 15,500 original miles

R68GTO

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Re: At a loss - engine stalls under load
« Reply #32 on: July 19, 2022, 02:17:45 AM »
Update....I sent the carb to Eric who found a few minor issues plus found the rear float was set near the bottom of the bowl.  He said that would definitely cause my stalling at heavy throttle.  At one point I had checked the float level in both bowls and set them to the bottom of the sight screw hole but obviously jacked something up.  I won't have the carb back in time for the SuperCar reunion but think I have it running good enough to do a few smoky burnouts and take a couple of easy passes with it.  It's been roughly 50 years since this car made its debut on the strip as Rat's Nest 8)
1969 427 COPO Camaro Lemans Blue/Black, M22 4 speed, 15,500 original miles

WaltZ

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Re: At a loss - engine stalls under load
« Reply #33 on: July 19, 2022, 05:07:44 PM »
Just throwing this out there.
After the floats checked, try increasing the squirter size +2 and test for any difference in stumble,
if it's better, then try the next accelerator cam up, try again and if the stumble is lessening, try the next couple of cams.
Had this stumbling and sometimes stalling issue with my stock 302 and when bumping up the accelerator cam, it took care of the stumble and stalling, therefore it was starving for fuel during load and acceleration by the pump cam curve not being enough.
It may be a good idea read and understand how these cams can affect your performance, for better or for worse.
Been thru it and I know your frustrations. Sometimes it just the simple checks we overlook.
Good Luck

R68GTO

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Re: At a loss - engine stalls under load
« Reply #34 on: July 26, 2022, 11:37:55 PM »
Got the carb re-installed and it is 100% better so I guess I can confirm that I "jacked it up" somewhere along the line.
1969 427 COPO Camaro Lemans Blue/Black, M22 4 speed, 15,500 original miles

David K

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Re: At a loss - engine stalls under load
« Reply #35 on: August 05, 2022, 01:23:02 AM »
Glad itís fixed. Refer to post #13 for the possible issue cause.