wraplock

I had a friend had this happen on his L88. When he installed the motor it ran great but after a hundred miles or so it had a significant loss of power. I repeatedly told him to check his timing. He said he did (but he didn't) and finally decided he needed to pull the engine and send it out to a rebuilder. The next day the rebuilder called his shop to say he had found the problem. When the balancer was installed on the crank the key in the end of the crank had rotated out of the keyway. With no key to stop it the balancer would creep a bit each time he hopped on the throttle or shut the engine down. Had he put a timing light on the balancer he would have seen that the timing marks in no way lined up. BTW the key was found in the oil pan. Start with the basics as Frank said, check your distributor.

Don

steve meltzer

This, by description is an acute event, not chronic like messed up wires (in wrong place, etc). And, I'll bet the work you did under the dash is a red herring. I'd go around the engine bay, engine running, even if rough, and use my propane torch (unlit!!) to check for vacuum leaks. You could also have a piece of dirt, or other debris in any of the passages of the carbs. After you check the other things, like loose dizzy hold down bolt, etc you'll need to pull the carbs. They get blamed for lots of things, but they could be the issue here. steve

ADD: checking the timing is a great idea and it's easy. You'll have to pull the vac lines to do it, and when you do, if there's NO change in the engine speed you've probably go a vac leak.

VincentLuong24

Thank you guys so much for all the responses and suggestions! I checked the distributor hold down and it was solid. The timing is at 6 degrees BTDC. I think I found my issue. I didn't set the points correctly. I finally used a dwell meter this morning and once setting it to 28 degress the car ran great! No more backfire (from the carb) and smooth revs. I do still hear an occasional miss on the passenger side still but definitely not as often. The car definitely runs better now. Once again thanks again so much and sorry for the stupid mistake.

Frankie the Fink

Good for you! If the passenger side miss is just an occasional instance of that bank "dropping shots" at an idle it could well be a mixture setting.

VincentLuong24

Thanks! I'll mess with the settings a bit and come back with a response. This forum is awesome and superly active! I never would have imagined a response rate such as what I have experienced here.

Frankie the Fink

Well - you just have to temper what you do with some of the responses you get here. Some will have you tearing in to an engine when the issue is really quite simple and easily fixed !

Gary's '66

Glad you got it fixed although I have to say I'm a bit confused. When you originally posted you said the motor was running bad after you worked on a few non distributor issues and BEFORE you started fooling with the distributor at all.

VincentLuong24

I failed to mention that when I inspected the original points system, the contact ring was broken in half. This was what lead me to begin replacing the system with the Pertronix and then to the mechanical replacement. Hope this clarifies things?

JohnZ

Can you expand further on what you're calling the "contact ring"?

MikeM

It doesn't explain why the Pertronix didn't fix it.

Did your engine have a factory transistor ignition?

VincentLuong24

Sorry I didn't know what else to call it haha here's a picture.

VincentLuong24

I think the Pertonix system just didn't work. This isn't the first time their electrolenic system failed me. I've gotten bad results following an install of their system on a GT500KR.

How do I tell is it has transistor ignition?

JohnZ

I've been working on these cars for 50 years, and have no clue what I'm looking at - what is that a picture of?

Frankie the Fink

This should be good!

decarmine

markdonc

Isn't that a picture of a "Uni set" points & condenser in one piece"? It's been probably 20 years since I've used them, but that is what I'm guessing.

Kerrmudgeon

Let's see, recent rebuild and ran good. Changed the oil and soon it ran bad.....did you use a zinc additive in the oil? Check the cam.

kcust62

John...perhaps this angle will refresh your memory!

JohnZ

Nope, I've never used a "Uniset", but now I remember it from the photos.

babbah

Looks like its one of the actual 2 point contacts - the stationary one - That one is is missing half of it's "contact pad".