At the track last night it would level off and loose power?

NHscamp said
Thanks for all the replies it is sounding fuel related, I built the engine and car but I know nothing about tuning and such.

To answer your questions It was the cars first time out.

Ran 150 degrees the 30 mile drive over and 180 degrees on the track.

Timing is 15 degrees and all in at 2500 35-40 degrees. Mancini elotronic distributor with built in performance curve, hei coil.

Exhaust is 2.5" with dynomax straight thru mufflers

Manual fuel pump 5/16 line and 5psi fuel pressure , Eddie performer 750 carb.
Run times were;

R/t. 1/8. 1/4
.159. 9.75@70mph. 89.42 mph
.574. 9.8@69mph. 87.58
.869 9.9@ 64. 80.22 mph

Did you pull the plugs? That will let you know if your running lean or rich just by looking at them. I would try to get a hard number for your total also.
Mine likes 36* at 2500 rpm.

My car used to have a pretty bad hesitation as well. If I was cursing and floored it quickly my car would stumble then come into power. I put a new carb on it last night and that helped the issue out a bit but I wasn't able to tell how the car was doing at high rpms in third gear.

If you have another carburetor then take it to the track next time and make a pass with each one and see if that helps at all.