I'm having an issue with the performance of my Chevelle and hope someone can shed some light on what to do next. I think it's a carb and fuel starvation issue, but maybe not. Here goes: 1200 miles on new 415 SBC mouse crate motor. Car accelerates great in first and second gear, shifting at 6000 RPM, then the car wants to "hold back" in third gear at 5000 RPM. No detonation, spark plugs look great and I feel I have the timing right on the mark. Running a 750 Speed Demon w/ mechanical secondaries, 82 primary / 91 secondary jets, Holley 110 GPH mechanical fuel pump. WTF?? :mad:

Here's the rest of my combo: Performer RPM manifold, XE274 Comp Cam, Dart Iron Eagle 215 cc runner heads, 1 5/8 Hedman headers, Pertronix HEI w/ MSD 6A, TH 350 w/B&M shift kit, 2400 stall, 10 bolt 4:11 posi rear.

I was contemplating a change of fuel pump to a Holley 130 GPH and a change of carb to a Holley 950 HP since many of you have been very pleased with the results. graemlins/thumbsup.gif

Please let me know what you think. Oh yeah, I have no weather issues, I live in Hawaii!! :D
Thanks in advance. Don

What cam,converter, tire size,heads,header size,gear ratio. Does sound like a fuel starvation issue. Install fuel pressure gage at recommended psi. of carb manufacture=7psi is what I run. Why would you change to Holley 950hp! Thats what I happen to by running on my 468bbc! Goodluck with figuring out the problem! :cool:

Blazerbob, Fuel pressure gage installed, reads 7 psi. Thanks. Don

You have good fuel pressure, but do you have good volume? What size fuel line are you running? Harold recommends 1/2 inch line. I have 3/8 line, but I plan to upgrade it soon.