1971 CEC solenoid and vacuum

[John]

Re: 1971 CEC solenoid and vacuum: Jack & Clup

Point gap not checked in three years or 6,000 miles? I would look there. For every one degree of dwell, two degrees at crank. The so called shooter or accellerator pump cannot be checked by sight. It may appear to o.k. but not supplying enough fuel for the engine to function properly under load. Suggest a carb blueprinting by Avanti Performance in Penn.

[John]

Re: 1971 CEC solenoid and vacuum: Jack & Clup

Point gap not checked in three years or 6,000 miles? I would look there. For every one degree of dwell, two degrees at crank. The so called shooter or accellerator pump cannot be checked by sight. It may appear to o.k. but not supplying enough fuel for the engine to function properly under load. Suggest a carb blueprinting by Avanti Performance in Penn.

[Patrick H.]

Re: 1971 CEC: Clup was right

Actually, I probably haven't checked the points in closer to 9000 miles over the past 3 years, but what's a few miles on a Corvette? Or, I might have done it when my rotor fell apart last year. I can't remember. I was just so relieved at the time to learn that it was only a rotor that went out and not something more serious.

Anyway, the accelerator pump has been changed regularly (for various reasons) over the past 3 years, and is fine.

I adjusted the secondary actuation as recommended by Clup, and the carb works like a dream now. No more black smoke and MUCH better acceleration. Actually, I remember now that when someone worked on another portion of the carb for me last year he made some comment about adjusting the secondaries to "come in a little faster" for better performance. I wasn't sure what he meant at the time but I guess I found out!

And yes, now it's time to double check my timing and dwell as well. Then, hopefully later this summer the MSD box goes on.

Patrick

[Patrick H.]

Re: 1971 CEC: Clup was right

Actually, I probably haven't checked the points in closer to 9000 miles over the past 3 years, but what's a few miles on a Corvette? Or, I might have done it when my rotor fell apart last year. I can't remember. I was just so relieved at the time to learn that it was only a rotor that went out and not something more serious.

Anyway, the accelerator pump has been changed regularly (for various reasons) over the past 3 years, and is fine.

I adjusted the secondary actuation as recommended by Clup, and the carb works like a dream now. No more black smoke and MUCH better acceleration. Actually, I remember now that when someone worked on another portion of the carb for me last year he made some comment about adjusting the secondaries to "come in a little faster" for better performance. I wasn't sure what he meant at the time but I guess I found out!

And yes, now it's time to double check my timing and dwell as well. Then, hopefully later this summer the MSD box goes on.

Patrick

[Patrick H.]

Re: 1971 CEC solenoid and vacuum

Hi Paul!

You had to be there to appreciate it, but after the C3's were getting 46 to 48 second times on our course all day and the other C3-owning member in our club allegedly got a 42, I really couldn't believe it. After all, I KNEW that I had been going faster than him, and I had just touched the 45's. Anyway, I was so determined to beat him that I just kept it at 10/10ths the whole way through and came up with a 39.7. The best times of ANYONE were only in the low 36's, and from a highly modified ZR-1. Anyway, my time was better than many of the "regulars", and this was my first autocross. Maybe "the force" was with me.

Anyway, if you see the now-disconnected post near the bottom of the page, you'll see that I found out that Clup was right. I tightened down the secondary actuating spring, and the carb works much better. It was "******* it" off the line because the air valves were opening too quickly and I was both losing my vacuum signal and dumping fuel down the carb. It works just fine now.

So do you think I could have gotten in the 38's with a carb that worked right?

Patrick

[Patrick H.]

Re: 1971 CEC solenoid and vacuum

Hi Paul!

You had to be there to appreciate it, but after the C3's were getting 46 to 48 second times on our course all day and the other C3-owning member in our club allegedly got a 42, I really couldn't believe it. After all, I KNEW that I had been going faster than him, and I had just touched the 45's. Anyway, I was so determined to beat him that I just kept it at 10/10ths the whole way through and came up with a 39.7. The best times of ANYONE were only in the low 36's, and from a highly modified ZR-1. Anyway, my time was better than many of the "regulars", and this was my first autocross. Maybe "the force" was with me.

Anyway, if you see the now-disconnected post near the bottom of the page, you'll see that I found out that Clup was right. I tightened down the secondary actuating spring, and the carb works much better. It was "******* it" off the line because the air valves were opening too quickly and I was both losing my vacuum signal and dumping fuel down the carb. It works just fine now.

So do you think I could have gotten in the 38's with a carb that worked right?

Patrick