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Discussion Starter · #1 ·
I ran my car this past weekend and had some issues going on. My times were off by 1.5 seconds, and my mph was off by 9. I usually run right around 14.01-.03 at around 98.0. I couldn'd even hit a 14 on saturday.

I have a 383 sbc, quadrajet, hei, taylor wires, and ngk plugs. Timing was set at 34* and I made a couple of passes with it at 36*. Car just felt completely dead throughout the rpms range. Fuel pump and carb have very little time on them, less than 250 miles. I removed the inline filter and it felt a little better but not much. I pulled all the plugs, the 3,5,4,6 are all a nice brown color, but the 1,7,4,8 are all rich?????

Any thoughts on what could be going on or which direction to head in, is appreciated., Thanks B.
 

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Discussion Starter · #4 ·
I double checked the timing tonight and made sure it was at 34*. I have a brand new sears dial back light and the timing on my other chevelle was right on, so I think the gun is good. The distributor hold down nut is tight, and it takes some force to move the distributor a degree or two. COuld the distributor be taking a crap on me? I always thought they are either good or bad, but no real inbetween.

Plugs are gapped at .40, running good fuel, no apparent lifter/valve noise..
I have a stock ac delco hei, I am going to try tommor, the current distributor is a proform, supposely made in Australia but probably made in china...

I am trying not to let it get me down, especailly because I am weak at tuning and if its the carb, I will be in bad shape.
 

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Discussion Starter · #6 ·
The Proform distributors are truly a POS. Check for rotor/cap/wire problems. Make sure all the plug wires go to the correct plugs.
Thanks I will.
Yeah I know, something I have learned the last year or so, is not to try and save money on certain parts. I hope this other ac delco hei will change something.
 

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Discussion Starter · #8 ·
Well the 60ft was off by 3-4 tenths and it just felt like there was an extra 500 pounds in the trunk. Usually by 3000 rpms I can feel the motor pushing me back into the seat, but not lately. It's just kind of gutless. Idles and starts good, no smoking, ect. Alt is charging good at 14 volts, belts are tight, I'm just not producing the same power as I have been. All the rocker arms feel snug to the touch and there is no extraordinary valve train noise. Thanks B.

When I made my best previous pass of 14.010, all the plugs looked very rich.
All new plugs were installed about 1 month ago...
Here is a picture of one of the current plugs.
 

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If your running pump gas. I have gotten bad or weak gas before and this will make a big differance. Maybe not 1.5 sec put still a big one.
That is rich,,, Like what was said before check Cap and Rotor. I would got with one step hotter plug. If that doesn't help the rich issue then you'll have to go leaner on the carb.
I got down to 12.9 in the motor I have now and have to change the plugs Very often to keep it top notch.
Low timing will also make it seen sluggish tho this doesn't appear to be your problem..
 

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I bet your valvesprings have gone away
 

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I know you said you have a new pump, but I've had new stuff go bad too!!

Check your fuel pressure. Also, try swapping a carb and seeing if the performance picks up. Also, check for a vacuum leak and look at the oil for any contamination. You could have an intake gasket leaking.
 

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It sounds like this engine has ran well in the past, so I would start by asking you what all has changed? Different plugs, timing, carb changes? Judging by the looks of that plug, fuel delivery issues would be the LAST thing I was looking at. That is WAY rich and doesn't appear to have enough timing. Have you had a vacuum gauge on the car? If not, that would be the very first thing I would do. It will tell you a lot
 

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Check to be sure that the choke flap is wide open and staying wide open when the motor is warmed up.

Alot of the early Q-Jets had a "safety" tang that kept the secondary air valve from opening until the engine was warmed up. It was operated by the choke linkage. If the choke flap is not open ALL THE WAY, it may keep the tang from releasing the secondary air door.

When you go to the floor, the secondary butterflies open because they're mechanical. If the air door doesn't open, then it'll be running just on the primaries of the carb. This will cause all sorts of fuel distribution issues.

Wire the choke flap and linkage wide open and then poke the secondary air door with your finger. It should open freely with only the resistance from the spring that controls it. It SHOULD NOT hang up at all. If it does, you gotta find out what it's hanging on.

Then, with the ENGINE OFF and the choke linkage wired wide open, have someone get in the car and mash the gas pedal all the way to the floor. You hold open the secondary air door with your finger and look down inside the secondary side of the carb with a flashlight. The throttle butterflies should be VERTICAL and wide open. If they're not, then the secondaries are not full open and you'll have to adjust the throttle linkage till they are wide open. If they're not wide open, that will cause fuel distribution issues, also.

Another thing to check is that all the screws are all tight in the top of the carb, especially the two countersunk ones that are down inside the primaries nest to the boosters. Also, be sure the secondary metering rods are still hanging on the hanger and the hanger is still in there.

Just some more things to check.:)


Randy
 

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Discussion Starter · #16 ·
is there any miss or popping under load?
There is a little popping when I first gas it from a stop or try to completely mash the pedal.

I have the electric choke wired up corrrectly and the choke is defienately staying open after the motor is warmed up.

The secondaries are also opening all the way at WOT....

I changed the oil last night, looked good, nothing suspicious.

To check the vacuum do I plug the gauge into the carb or into the manifold???

The Valvetrain(Erson) is also very new, and the springs seems too be in good shape, but I really would not know how to check this out, except that they all have load on them and are tight to the touch. It's a roller cam and i have properly lashed the valves in OCtober when I first got the car to the track.

Do you guys think I should try this other distributor I have??

Thanks for all the help, keep it coming!!!!
 

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I bet this is either a carb issue or a fuel issue, q-jets especially have very small fuel bowls so you need a good system to keep them full, also make sure you have wot
 

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Discussion Starter · #20 · (Edited)
I bet this is either a carb issue or a fuel issue, q-jets especially have very small fuel bowls so you need a good system to keep them full, also make sure you have wot
I think there is plenty of fuel, plugs are rich to begin with. My pressure is good at 6.0-6.5 psi, holley mechanical pump rated at 110 gph and I have WOT. Thanks for the help.

I dropped in my other distributor and the car seems to have awoken a little bit. It is hard to tell because the car is not registered so i can only very carefully cruise the adjacent neighborhood and my street.

Anyone know how much mechanical advance a stock ac delco hei replacement would have? I am having a little trouble setting my total timing. I have the initial set between 12-15*, and I am thinkning that all the advance is not coming in until above 4,000 rpms, which I do no want to really rev the car that high in park anyways, unless I have too.

Which spring would bring the advance in quicker??? A or B
 
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