seegrins408

Recent purchase of a 66 Vett with supposedly the L79 engine.

The Florida dealer lied about the condition and sent me pictures of another car other than the one he shipped me...Stupid Me!

The engine was represented as the original 327/350 HP engine with solid lifters and a rebuilt Holley. The carb is in bad condition and the car performs like a 200 HP engine. No smoke but it feels like a 2 barrel carb. What would be the best replacement carb? Summit Racing with 3 separate calls have made 3 different recommendations from a 600 CFM to a 750 CFM Holley...Please advice if you have the experience!

I took the car into a shop that is doing the carb replacement and asked them to adjust the valves. They asked what cam was in the engine and what are the specs of the cam? Of course this assumes it's the original correct cam. Because of not knowing the specs on the cam and having confusing advice about the right replacement carb the car is sitting in the shop waiting for me to gather the information...Please help!

Scott Marzahl

Well a L79 is a hydraulic cam motor with 222 degrees duration @.050" with 114 LSA and shy of .450" lift. The correct carb size is 585cfm. If it is the original Holley have it rebuilt, if not I believe Holley has a restoration carb available for it

Here​​​​​​ is a nice example of what carb you should.have.
http://m.ebay.com/itm/112262626440?_trksid=p2385738.m2548.l427 5&_mwBanner=1

ricks327

First, Welcome to the Forum. Some of our comments will be spot on and others might be a tad off center.
The main thing I'm seeing is that a 327/350 engine was not an original solid lifter engine. Have you checked the engine stamp pad? What are the numbers stamped there and if you have a photo of the stamp pad, it would help for a starting point.

GearheadJoe

The original carb on the L79 was a 585 CFM Holley with vacuum secondaries. For a stock L79, something similar in size will give the best overall driving experience in normal street driving.

The original cam in the L79 327/350 used hydraulic lifters, not solid lifters. Since the adjustment procedure is completely different for hydraulic lifters versus solid lifters, it's important to figure out what you have.

Some would say that you need to pull the intake and look at a lifter, but I suspect that a knowledgeable old-school mechanic could figure it out without pulling the intake.

In my experience with adjusting hydraulic lifters with the engine running, the first step is to take up the lash until the lifter stops tapping. Then you add another 1/2 to full turn on the adjustment nut to put the hydraulic lifter piston halfway down in its travel. At this point the engine starts to stumble and run badly for about 30 seconds while the hydraulic lifter adjusts itself. Then the engine recovers and runs fine.

My guess is that with solid lifters, the engine would never recover from the stumble because the solid lifer cannot self-adjust. So, this might be an indirect way of figuring out what kind of lifters you have.

Hopefully the cause of your low power situation will be something simple like the carb, distributor, of valve adjustment. If the engine is not smoking, the rings are probably okay, but there could be a problem with a wiped cam or a burned valve. The key to diagnosis is to start with the simple things, such as fuel and ignition, and then move progressively to more serious things, such as a wiped cam or burned valve. Sometimes you get lucky and the entire problem is due to something simple.

phil2302

An engine with solid lifters will sound different from the same engine with hyraulic lifters.
Often times non mechanics will hear the clackety clack of an engine with solids and mistakenly think it is starving for oil to the heads or the rockers are too loose.
I would guess if you engine idles with out any significant noise under the rocker covers it has hydraulics.