not running like expected at the drag strip

[GhettoRacingKid]

try some spacers at the track that should help the top end. it might hurt the bottom end but only slightly.

like others have said. check to make sure the secondaries are opening up.

 

[chevy2480]

Well i had a 9.5 sbc 350 with iron 185 heads ,comp 292h cam ,victor jr intake and a 750 on top. Also had a 3200 stall with 3.42 gears in a cutlass best the car went was 12.23@ 110.

So that being said i would go single plain intake and possible a bigger cam seeing how you have a great set of heads its possible they are to big for your smaller cam. By the heads being bigger you are not acheiving max air volocity so the heads are not letting your motor run to it full potential on top end. Your timing is probably a little on the low side try 34-36 total and see what happens.

 

[khan0165]

I don't have much experience with the Holley vacuum secondary carbs... Are they spring opperated? Is it a simple mater of changing out to a looser spring?
... what kinda vacuum is required to have secondaries fully open on a Holley 750?

have considered a mechanical secondary carb?

 

[larryo454]

Hi get a converter it is killing your 60ft big time and timing all in at 31 not a big help.

 

[khan0165]

Hi get a converter it is killing your 60ft big time and timing all in at 31 not a big help.

correct... the more timing advance, the more you take out of your top end...
... try going 20 deg idle timing, or set it to 34 @ 3500rpm

 

[khan0165]

must watch!
http://www.youtube.com/watch?v=4xOiJQj6CSU&NR=1

 

[Chris Van]

Not really sure what I gained from that but my 83 has a 750 vacuum secondary carb and even after trying several bigger and so called better carbs I have always resorted back to the trusty ole 750 vacuum on this application anyway.

 

[MD13ailey]

I had a similar problem, and r you running a drop base air cleaner? and how tall is the air cleaner element. my problem was the air cleaner top was to close to the carb and was robbing me of almost a full second. just for grins take your air cleaner off and see what happens.

 

[78MC-BBC]

i would also look into upgrading the rear suspension, like some better control arms and better bushings, alot of g-bodys respond well to rear suspension mods. And definitively check out the stall, probably want like a 2500 stall converter

 

[Chris Van]

For some reason when I posted the above comment, the link to the video was the only thing showing up for me. The first page wasn't even here..... But now I see what it was meant for.
Anyway, I think you will benefit more from a higher stall converter than anything else. However, you are then creating traction issues if you are running regular street tires. More stall and a set of slicks.
You said the engine just doesn't pull past 4000 rpm?? Does it not rev much past that or just quits pulling??