Mechanics

CHEVROLET CAPRICE DISTRIBUTOR PROBLEM

1989 Chevrolet Caprice

I have a question and need your advise before I start spending money on mechanics to give me the run around. Please bare with me as I try to give as much detail as possible. I have a 1989 chevy caprice with a 1995 chevy engine converted to carburetor and mechanical fuel pump with 1998 vortec heads. The transmission is a 350 turbo with shift kit. The problem is it fires up fine but when driving and speed reaches 45-55 mph the car loose all power as if it cut off. The strange thing is the car do not cut off but petal to the floor equals no power just stumble sorta like running out of gas. For some reason if I ease off the petal and allow the rpm to come back down the car runs fine until I reach the speed of 45-55 mph again. I have noticed a small tap sound like a lifter when engine first crank while cold but once ruuning it stop. I noticed this engine distributor do not have a vacuum advance nor is it hooked up to a computer just plain hei no vacuum advance. The oil looks good and no noticeable smoke out the exhaust while idle or drive. I do feel a slight hesitation while idling but not enough to complain about. The plugs and wires are new. The exhaust is is dual 2/ 1/2 inch with headers and dyno max super turbo mufflers. Any information you can provide to give me a starting point on what to have checked out would be very helpful and Thankful.
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Mrcsmith
November 16, 2012.



Check fuel pressure.

Do you have cat converters?

You need to see total timing with a light. Does it have a computer for controlling timing?

Roy

ASEMaster6371
Nov 16, 2012.
Thank you so much for the reply. I have no converters also there is no computer controlling the timing. I also think the timing was set by ear.

Tiny
Mrcsmith
Nov 16, 2012.
Ok, first you need a distributor with a vacuum advance. I suggest getting a weight kit for it as you have performance mods.

I assume you have a performance cam so we will need the initial timing setting as well.

If no info on the timing, we will have to set total advance at 2500 rpm

Roy

ASEMaster6371
Nov 16, 2012.
Thanks and I will get a distributor with vaccum advanced. The cam I have installed is a lunati 1000LK. The specs are 204 / 214 .420” /.443” 112 / 107 1000-5000 Rpm. My carburator is a summit 600 cfm. I was messing around today and turned the distributor and took a test drive and notice the car would reach up to 65-70 mph before falling flat like it was doing at 45-55 mph. You guys have been such a help.

Tiny
Mrcsmith
Nov 17, 2012.