I hope someone can help me out as I am becoming very frustrated and losing interest in my car as a result. I have a 1969 L46 Corvette that, from what I can tell, is all stock. It has the standard 4 speed transmission, TI ignition and a 3.70:1 rearend. I had hoped that the car would perform similarly to an LT-1 (I know it would fall somewhat short) but, instead the car has always left me disappointed.

When I first bought the car, I took it to Conte's in Vineland and asked them to go over the car, give it a tune up and put together a list of what it needed in the future; prioritizing what was most important. That visit was a dud as the tune up didn't change the car's performance and I never did get any priority list. Next visit was to Corvette Paramedics in Mt. Holly. They got the car running a little better but, still not up to my expectations and, again, no list.

My latest attempt was to have a local Corvette guy try his hand at the car. He found old plug wires and old plugs so my guess is that neither of the previous shops did a very thorough job of tuning the car. The latest guy suggests that I have the carb rebuilt, which I do. While I am at it I order new hard lines going from the fuel pump to the carb and a new fuel filter. I figured, since I removed the carb, I surely can replace it right? Well now I can't get the fitting below the filter to tighten enough to stop leaking; it is barely weeping but, I can't get it to stop.

I am at my wits end and could use some recommendations as to who might be able to get my car to run like an L46 should. Am I expecting too much from this combination?

Please, please someone help; I can't drive the car with the leak so I am limited to local tuners (I live in Little Egg Harbor, NJ)

Thanks

Welcome aboard! I'm a mopar guy so I'm of little help, however I'm sure someone will chime in soon. The only issue is we have a two day race this weekend at Lebanon Valley Dragway so a good number of the guys/gals are loading trailers,packing cars or driving to the track. Now with the slight leak is there a metal or plastic washer between the fitting and the body of the carb?

I am in no super big hurry to get the car figured out so I can wait a week or two if that's what it takes. The fuel filter that is causing me fits is the metal one that attaches to the hard line coming from the mechanical fuel pump. There is a fuel filter that is inside the base of the Quadrajet but that is not the one giving me a hard time.

Is the fuel line stainless? They can be a bear to tighten. If you can't get it to stop leaking, I would take it apart and see if there is a burr on the line, which might prevent it from sealing. What is the problem with the performance? Is it missing, idle rough, etc?

I bought the steel lines to match what was there. The car is not stumbling or anything; it's just not as quick and responsive as I had originally expected. Due to past experiences with other shops I was hoping I could find someone who knows these cars / engines and how to get the most out of them.

These motors respond to simple tuning upgrades. If you are going to use it on the street try eight degrees initial advance and total around 32 degrees at about 3400 RPM. Listen for pinging when you get on it or lug it in 4th gear.

I assume you are running the QJet on this motor. Find someone with an gas analyzer. Should be 14 or so to one. Greg Geisler in NJ sells jets and rods for the Qjet. Of course you should have good plugs and wires in it. Is it converted to electronic ignition yet? Have you ever had the car to the track? If so what kind of times do you get. this car should be good for high to mid 14,s with 3:70s. It sounds as though you have little experience but don't give up. you got a great car there. You might want to make a trip to Billy Attwood in Old Saybrook CT. Make it a day trip. You will go home with a big smile on your face.

It sounds like you need to have someone really go through it. Check the valve springs, cam lobes, valve job, recurve the distributor, set the carburetor up properly, etc.

My friend's brother in law bought a restored 67' L79 Corvette about five years ago. It flat out was a turd. The "rebuilt" engine was a joke. Poorly machined and assembled. Valve job that didn't seal, bent pushrods, valve tips that were razor sharp, worn valve springs, etc. I think it made around 240-ish on an engine dyno. After the rebuild it made just shy of 370. He had it redone by an old super stock racer, and his attention to detail was obvious. Totally different animal after being gone through the right way.

I am in Florida, so can't help you with a shop recommendation. But, I am saying that when choosing a shop - get a detailed list of things they will check, and procedures they will perform. If it's a short list, run.

JMHO

The Q-Jet was just rebuilt by Eric Jackson of Vintage Musclecar Parts in Ohio; he came highly recommended so I am confident that the carb is not the issue. The plugs and wires have just been changed and it is a factory transistorized ignition car.

I have not taken it to the track and probably won't as I can't afford to break anything on it.

An L79 making 370 ish on the dyno is strong; I would be thrilled with that out of my car.

Good news, Albert Galdi has offered to come pick up my car and try to figure out what might be making it run like crap. He suspects that the distributor is the culprit.
I hope to know more by the end of the month; I am quite confident that he will be able to get the car figured out for me.

Make sure that a compression check is done to determine that all cylinders have appropriate and consistent pressure. Also, have them check to be sure there are no vacuum leaks.

I ran into a problem a few years ago on an old motorcycle that I just couldn't get to run quite right. After messing with the carbs (4 of them) for a while, I could get it to run well at low speeds or high speeds but not both. After someone suggested doing a compression test, I discovered that 2 of the 4 cylinders were low. When I tore the engine apart I discovered a large score on the cylinder walls of those 2 cylinders that was obviously from an earlier failure that looked like it was from the wrist pin retainers since the score marks lined up with them. It was apparent that someone just slapped new parts back in and threw it back together. After rebuilding it correctly, the previous problems went away.

Good luck,
Kevin

Thank you for the suggestion; I will ask that this be done during the diagnostic process.

Latest update; Albert came and picked up the car and discovered a whole host of issues, some bigger than others. There were some bad / missing vacuum lines, the timing was WAAAY off and the biggest problem was the distributor needed to be rebuilt. Since the car is equipped with a factory TI set up I sent the distributor, coil and amplifier off to Dave Fielder at TI Specialty for the work.
Dave had to completely rebuild the distributor and replaced the amplifier due to a broken mounting stud.
I hope to have everything in Albert's hands by the end of next week and am looking forward to getting the car back; I anticipate that it will be a completely different car.

Glad to hear you are making progress.

Albert has the car back together and running; MUCH better than before. He was going to deliver the car to me last Saturday but, due to the forecasted snow in our area, he decided to hold off until this coming Saturday.