Help any input will be welcome

Ed Carpenter · 02-28-2013, 05:29 PM

I had this problem last season. Had the motor redone. Found a problem with the rear end(it was binding up) got that fixed. Still same deal. Let the clutch out at 8600 lugs the motor down bad. On the graph it pulls it down to 3000. Then if you stay with it and shift the remaining gears at 8000 its ok. When I came up the return road in 2nd I got on it pretty hard and shifted it. It runs real strong. Im open to anything. Thanks.

Jeff Lee · 02-28-2013, 06:26 PM

Quote:

Originally Posted by deuces wild

I had this problem last season. Had the motor redone. Found a problem with the rear end(it was binding up) got that fixed. Still same deal. Let the clutch out at 8600 lugs the motor down bad. On the graph it pulls it down to 3000. Then if you stay with it and shift the remaining gears at 8000 its ok. When I came up the return road in 2nd I got on it pretty hard and shifted it. It runs real strong. Im open to anything. Thanks.

Something to do with the fuel system.

R. Thorne · 02-28-2013, 09:48 PM

4gc carb? Check for leaking brass floats and float setting. Ron.

james schaechter · 02-28-2013, 11:07 PM

Some ignitions like a msd digital programmable have provisions to adjust timing on the launch. Just taking a swing, but if for some reason your timing was retarding a ton on the launch, maybe that would be an issue. It would not show up anywhere else.

Ed, are you running the 283 now? 4 jets have big float bowls. I would be shocked if you ran low on fuel, but what if they were set too high and dumping fuel down the intake when you launched?

gmonde · 02-28-2013, 11:53 PM

do you have a o2 reading ????,, whats the first gear ratio?? gmonde

Mike Taylor 3601 · 03-01-2013, 09:38 AM

It would help to open secondarys on the line 8600 is just where it starts to sound good,LOL
I think you have some good ideals posted, I know it's a 4GC but I have had similiar quadrajet problem,needle and seat will slightly leak won't run over just idles about 100-200 rpm slower and bogs on launch,took me a little bit to find the first time,on Q-jet I have to take off top of carb and hold float pivot pin down and turn on fuel pump it will take 1-2 minutes for fuel to creep up it leaks so slightly,maybe able to try on 4GC. new needle and seat seals,but now I check them before putting top on.
Mike Taylor 3601

02-28-2013, 05:29 PM	#1
Ed Carpenter Live Reporter Join Date: May 2006 Location: Dripping Springs, Tx Posts: 2,709 Likes: 186 Liked 520 Times in 132 Posts	Help any input will be welcome I had this problem last season. Had the motor redone. Found a problem with the rear end(it was binding up) got that fixed. Still same deal. Let the clutch out at 8600 lugs the motor down bad. On the graph it pulls it down to 3000. Then if you stay with it and shift the remaining gears at 8000 its ok. When I came up the return road in 2nd I got on it pretty hard and shifted it. It runs real strong. Im open to anything. Thanks. __________________ Ed Carpenter 2005 Chevy Cobalt A/SM Race Engine Development

02-28-2013, 09:48 PM	#3
R. Thorne Member Join Date: May 2009 Posts: 182 Likes: 62 Liked 100 Times in 33 Posts	Re: Help any input will be welcome 4gc carb? Check for leaking brass floats and float setting. Ron.

02-28-2013, 11:07 PM	#4
james schaechter VIP Member Join Date: Dec 2004 Location: Cumming GA Posts: 1,988 Likes: 1,288 Liked 1,428 Times in 296 Posts	Re: Help any input will be welcome Some ignitions like a msd digital programmable have provisions to adjust timing on the launch. Just taking a swing, but if for some reason your timing was retarding a ton on the launch, maybe that would be an issue. It would not show up anywhere else. Ed, are you running the 283 now? 4 jets have big float bowls. I would be shocked if you ran low on fuel, but what if they were set too high and dumping fuel down the intake when you launched? __________________ James Schaechter 3163 STK

02-28-2013, 11:53 PM	#5
gmonde Senior Member Join Date: Nov 2007 Posts: 615 Likes: 56 Liked 165 Times in 59 Posts	Re: Help any input will be welcome do you have a o2 reading ????,, whats the first gear ratio?? gmonde

03-01-2013, 09:38 AM	#6
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,371 Likes: 352 Liked 304 Times in 102 Posts	Re: Help any input will be welcome It would help to open secondarys on the line 8600 is just where it starts to sound good,LOL I think you have some good ideals posted, I know it's a 4GC but I have had similiar quadrajet problem,needle and seat will slightly leak won't run over just idles about 100-200 rpm slower and bogs on launch,took me a little bit to find the first time,on Q-jet I have to take off top of carb and hold float pivot pin down and turn on fuel pump it will take 1-2 minutes for fuel to creep up it leaks so slightly,maybe able to try on 4GC. new needle and seat seals,but now I check them before putting top on. Mike Taylor 3601