I have an 85 camaro that i swapped a 350 into. Its a stock 350 block with a victor jr. intake manifold, a holley 650dp, and crappy sbc 882 heads. Im running hooker comp headers to a true dual 2.5'' SS exhaust dumped at the rear with 2 welded thrush mufflers. I also have an accel Distributor with HEI , 8g moroso wires. I'm using auto-lite ar24 plugs gapped at .045. My initial timing is set at 18.

The problem is when i quickly step on the throttle the engine stalls out but if i bring up the rpms more gently the throttle raises fine. It only dies under a hard acceleration. Also if i bring up the rpms to around 1200-1250 and then hit full throttle i get a bog and then it accelerates and the rpms climb like they should. It makes it such a PITA to drive.

Ive already replaced the primary needle valve. And the primary jets the fuel level in the bowls are set right when i look through the sight hole. I am getting streams out of the jets when i hit the throttle.

The car idles great and runs great aside from when i hit the throttle quickly it dies. If any of you can help me out that would be great. Thanks

 

Adjust your accerator pump

 

Yea thats what i was thinking. already brought the spring out a little more but theres no difference ill bring it out further and see what happens. Thanks. Anything else you guys think it could be?

 

Be sure it's working. Look down the carb and take a peek.

 

I took a peak. I looked down the carb and when i hit the throttle i get 2 streams squirting from the jet. The jet and pump seem to be working fine. Ill try and adjust the accel pump more in the morning but for some reason i think it is something else.

 

Well im going to bring this one back. After some time messing with the primary accel pump i decided the linkage was worn and old and i havent replaced the pump in a long time so. I went ahead and purchased the 50cc accel pump kit from holley. after installing it i noticed better response but the car still seemed to die but now at different points. When i give it quick throttle it works much better but then when i open it hard enough to open the mechanical secondary's the motor trys to stall. The rear accel pump is new and the jets of fuel are strong when pumping the secondarys. This happens even worse when driving. If i go to hit full throttle it surges/studders/hesitates to move and has no power untill i back off. What do you think can be causing this?

 

They could be opening to soon.

 

Can this also be the distributor? I have looked at it recently and i have an accel hei with no mech, or vac advance. I thought there was a mech advance but when I opened it up today there was nothing. Im thinking the distributor might have an electronic advance? There are 4 wires to a plug coming off the distrib and going to nothing. Originally it thought that it was fine they were just the wires that went to a coil and power but now i think i could be wrong. Some guys at the shop im at told me that the distrib with no advance will run the car but there will be no performance and there will be allot of the same symptoms that I have.

 

Me thinks you have found your problem.

Put a timing light on it, rev the engine and see where the timing, goes then report back.

 

Gonna try it out tom morning and see what happens. Ill let you know.

 

Dist is for computer controlled injection setup.
All spark advance controlled by computer which you don't have so you only have the inital advance

Bear in mind your combo is not the best;
stock motor/cam / crap heads, top end ( 3500 - 8000 rpm ) intake and DP don't make for nice bottom end response
Opening up the secondaries on hard accel just flat spots the engine because it is dropping intake port velocity = BOG
Would be much nicer engine with dual plane intake and vac secondary carb that opens when the engine NEEDS air ;
not when you want to give it

 

Yes I know the setup isn't the best its just something im working with right now. But it shouldn't act like it does now. I almost cant go anywhere without feathering the throttle. There is no power at all and the car go back and forth from bogging and running when i step on the throttle. It makes it a challenge just to get it down the block.

I'm going to be checking the timing today with the light to make sure.

I had single pump Holley 600 I believe with vacuum secondary's. The carb was a POS and everything needed to rebuilt. I Had a 650dp in the garage that was just rebuilt a few months before I took it off another 350 i figured i would be doing myself a favor by putting it on.

 

Well i just took out the timing light and tested the timing. its at around 16 idle and when I crack the throttle to maybe 2500-3000 it moves about 3 degrees and then stops there and it stays there through the band.

Im assuming that means there is really no advance. It should jump way more than 3-4 deg shouldnt it?

 

If it is the dist you mention above then it has NO advance at all ; in a EFI setup all advance is controlled electronically by the computer.

Buy the correct mech/ vac advance dist to suit a carb setup and set your inital advance correctly

 

I have a pickup with an invader 350 it was doing the same thing you described here. It ended up being my spray pump. Don't know if thats your problem but definetly something quick to check, and its an easy fix if that is the prob.

 

With a DP carb and 50cc pump he has plenty ( too much actually ) fuel; problem is he has no spark advance movement.

 

Just purchased a msd street fire hei distributer with a vac/mech advnace, with 8.5mm wires. A new high-flow fuel filter, 4150 series fuel log and a fuel pressure gauge are also on order so i can get a correct reading on fuel pressure. Should be in at the end of the week ill let you know how she runs when I get the parts on.

 

Well I put the parts on. I was not surprised that the distributor fixed my problem. The edelbrock performer manifold improved my throttle response and Im now able to read my fuel pressure(spot on at around 7). The car performs much much better and its actually a blast to drive. Thanks everybody for your help. Cant wait to finish building my top end now.