1974 Chevrolet Corvette L-82

**pajeff02** · 09-06-2011, 05:39 PM

Happy to report that the Corvette now has a working temperature gauge. I fired it off tonight and ran the engine up to operating temp while checking and comparing the gauge reading with my laser temp gun's readout. Just have to top off the coolant in the system tomorrow and then I will try to get the door pin switches to work properly. I fought with them before and had them working for a while, but something must be amiss as the light is now always on in the center gauge cluster.

**gary gross** · 09-11-2011, 08:22 PM

thats just one bad mutha shut yer mouth!! thats it!

**pajeff02** · 09-12-2011, 03:16 AM

Originally Posted by gary gross

thats just one bad mutha shut yer mouth!! thats it!

I guess I will take that as a compliment. Thanks!

**69PONTIAC** · 09-22-2011, 06:52 AM

good looking car,must be a blast to drive being a 4spd.

**pajeff02** · 09-22-2011, 11:57 AM

It has the M-21, close ratio Muncie transmission, so you get through the gears pretty quickly. I do enjoy driving it.

**pajeff02** · 10-24-2011, 06:18 PM

I pulled the wheels last night to swap over to the new tires. The Eagle ST's are at least 20 years old and are checking around the bead... time to go before one decides to blow and takes out the bodywork in the process. I picked up a set of BF Goodrich Radial T/A's at Fall Carlisle and dropped them off today for mounting and balancing. After pulling the wheels, I noticed that the rotor was just a bit wet on the right rear. Tonight, I had Sammie jump in the driver's seat and she pumped the brake pedal while I looked everything over. Sure enough, brake fluid began to drip off the caliper.

Removing the caliper is super easy on C3's as you simply remove a cotter key and slide out the pin to pull the pads. The caliper is secured to the backing plate by two bolts and there are no pins at all to mess with. Once the caliper was off, I of course had to tear into it to see what the problem was. My best recollection is that these were rebuilt calipers I purchased from CarQuest maybe 8 or 9 years ago. They have the lip seal and had not been sleeved. A rebuilt pair that has been stainless steel sleeved and upgraded to o-ring seals is on its way from Corvette Central for installation. I may as well swap out both and save myself the aggravation down the road. I considered rebuilding this one, but the pistons are simply too corroded to mess with imo.

**cpop98ws6** · 10-24-2011, 06:42 PM

Too bad you don't live closer Jeff, I could have mounted and blanced your tires

**pajeff02** · 10-24-2011, 07:16 PM

Nice toys!

**2002ssslp** · 10-24-2011, 08:36 PM

Wow, cool car. I remember when they were new, they were almost as fast as the SD455 TA's. I was in Jr. High and we bench raced these cars with stats, I never got to drive one but I always ment to. Good luck with it.

**pajeff02** · 10-25-2011, 03:10 AM

Thanks! I'm not real big on stats, but I think the hi-po L-82 small block may have been around 195 hp back in '74. It was the last year of the big block and the first Vette without at least one chrome bumper. The car actually handles quite well for late '60s technology and we have upped the horses under the hood to around 330 or so.

**2002ssslp** · 10-25-2011, 05:13 AM

HP was the only thing that car needed. It had the looks, handling and the WOW factor. Let us know what it runs at the track when you take it out.

**Firebirdjones** · 10-25-2011, 10:18 AM

L82's are great engines and real sleepers of the 70's that still had alot of go fast parts inside of it like the 350/350 hp hydraulic camshaft that has been GM's staple since the mid 60's, (222 at .050 and around .460 lift) off the top of my head..... 2.02 heads (although larger chamber) etc....GM just dropped the compression a bit, but it's nearly the same engine as the previous 350/350 HP that was in the 1969-1970 vettes. A little tuning wakes them up.
It's the L48's that were the real pooches

Anyway, I was going to tell you to get stainless calipers from Corvette Central but it looks like you got that handled. You won't have any more trouble with those.

**Smittro** · 10-25-2011, 01:33 PM

As always Jeff very nice! I'm not a huge fan of the wing tho.. Just my personal oppy..

**pajeff02** · 10-25-2011, 03:13 PM

Originally Posted by Firebirdjones

L82's are great engines and real sleepers of the 70's that still had alot of go fast parts inside of it like the 350/350 hp hydraulic camshaft that has been GM's staple since the mid 60's, (222 at .050 and around .460 lift) off the top of my head..... 2.02 heads (although larger chamber) etc....GM just dropped the compression a bit, but it's nearly the same engine as the previous 350/350 HP that was in the 1969-1970 vettes. A little tuning wakes them up.
It's the L48's that were the real pooches

Anyway, I was going to tell you to get stainless calipers from Corvette Central but it looks like you got that handled. You won't have any more trouble with those.

Just received shipping confirmation on them. Thanks for the info!

Originally Posted by Smittro

As always Jeff very nice! I'm not a huge fan of the wing tho.. Just my personal oppy..

I was also not a fan but it has sort of grown on me. I think they call it a "turbo wing" in the catalogues and I believe they still make them. Does look damn cool from the rear view mirror.

**pajeff02** · 11-04-2011, 05:51 PM

Ended up with a set of stainless sleeved O-ring calipers from Lonestar. The new one installed on the right side started leaking after I drove the car downtown to gas up. Incredibly, it is the rear inside piston which is what was leaking on the caliper I removed. Called Corvette Central and it'll be next week Wednesday before they can ship me a replacement.

**Firebirdjones** · 11-04-2011, 05:58 PM

Well isn't that just the pits....

**pajeff02** · 09-23-2013, 03:06 AM

Now that the power steering issues are sorted out (posted in the "Can Cars Hate?") thread, I am working on a couple of the remaining issues. I have adjusted the Q-jet so that the car runs and idles pretty good now, but am having some issues with the high idle on cold startup. I always pump the gas a couple of times (as you should on a carbed car) and that sets the choke and high idle cam. For whatever reason, after setting it the high idle has worked its way down. Once the car is fully warmed up, everything is good and I have no stalling. However, between start and warm up, I will have to feather the gas after driving a short distance and coming to a stop to keep it from stalling.

I was looking things over last night and realized that I have never adjusted the vacuum break. The electric choke itself seems to work fine and it's opening seems to be timed pretty good. This is a JET Stage II (stock carb was gone when Dawn bought the car - had a Holley Q-jet replacement) based on the later M4ME pre-electronic, so probably early 1980's. It has an adjustable vacuum break on the arm coming from the vacuum diaphram. My Q-jet books show this, but does not tell me how to adjust it.

If I understand it correctly, the vacuum break is supposed to allow the choke to crack open upon startup so that the air-fuel ratio backs off just a bit from full rich. Is there a procedure for setting this? Tightening the screw increases, or decreases, the rate (or amount) of opening?

**pajeff02** · 10-19-2013, 05:08 AM

Replaced the rear lower bumper supports last weekend. I noticed when washing the car that the bottom of the bumper was flopping around a bit. Both original pieces appear to have disintegrated over time. They were some kind of plastic or urethane material and just dried out and crumbled. Monkied with the headlight sustem and picked up a new set of control valves. I removed one from the car and then bench tested them side-by-side with my vacuum pump. They both responded identically to all tests, so it is not the valves acting up. Going to do some more thinking on this one...