[fast5]

on the track at WOT, after 3/4 of the quarter mile
my engine loses very smooth power. Only for about
a second ... than pulls like before???

any ideas??

its a 350 sbc with 142 Weiand and 750 DP

[a1supersport]

I'm sure you've checked your fuel level in both bowls already. Do you have jet-extensions on the secondary jets? What kind of fuel pump(s) are you using? I'm guessing the fuel levels are dropping enough that your jets are momentarily exposed...the rpm drops-off...and the fuel pump(s) are able to catch-up again. And that's when your power comes back. Sounds fuel-related to me. Unless anyone has other ideas.

[fast5]

Fuel level is bottom screw on front bowl, and a little bit
higher on the back one.

What are jet extensions ??

should be the stock pump (mechanical).

[sqzbox]

Extensions screw into the jet holes and the jet's screw into the other end. It put's the jets closer to the back of the rear bowl so the jet's won't run dry from the fuel sloshing to the rear of the bowl.
Being your only having a problem towards the end of the quarter, I would guess fuel pump pressure could be your problem. If your running a Holley, stay away from the 1 fuel line into a split dual feed as the primary bowl might be taking away fuel volume from the rear bowl. Easy fix is run your fuel line into a "T" with equal length's from the "T" to each fuel inlet on the carb from the main fuel line.

[fast5]

ok, this seems to be the right things to start ...thank you

[ericnova72]

Blown engines always require more fuel. The stock fuel pump is nowhere near big enough for the job, and I would suspect the issue is just as A1Super has said, you are outrunning what the pump can supply at higher rpm, classic symptoms.

[sqzbox]

Originally Posted by fast5

its a 350 sbc with 142 Weiand and 750 DP

Man.... don't tell me that weiand is a blower!

I hate it when that happens. I feel so stupid................