72 Olds Project

Hello everyone. Just drove my car for the first time down the street I live on. LOL I know I am playing it safe and we are missing parts...and a tag. Anyways, when I got in and drove off it stumbled very badly. Like an old man having to pay full price at a buffet. When I am under the hood and I rev the motor it is fine. It sounds very strong. What gives? I am at about 10-12 timing when on vacuum (carb vac), 455 C Heads, Edelbrock intake, Holly Carb, Factory HEI (with resistance wire gutted). Also when I shut it off it sputtered twice real quick and shut off. Yet I can start it right back up just fine. Does this sound timing related?

72 Olds Project

I forgot to mention I am using a new Holley 750. Did I maybe go with too big of carb? I would really not think so. Thanks!

815Cutlass1972

I'm no expert, but make sure your car is warmed up, before stepping on it. Your 750 Holley is fine. Is this recently re-built engine?

Beob

Whats timing with vac advance off? Should be disconected when timing.

Bill in NC

X2. Do you know what the total timing is set at? Is it only for a second, or does it take a few seconds to get past the stumbling?

72 Olds Project

Oh yes it was fully warmed up. I wanted to make sure I didnt have any issues first. Not sure actually what the total is, but my mechanic buddy did time it without the advance hooked up. He said too he thinks the timing is off still. We will re-time it again.

Hey Bill, you are practically my neighbor I live in Clemmons. It wasn't doing like a bad dieseling as I have been there before. Basically just right when I shut it down it chugged twice real quick and it stopped. Sort of like that knocking sound you get when running out of gas

72 Olds Project

Oh and to add...it will only do the clunking off after the motor is fully warm. If I was to do it cold then its not a problem. Now! Just a thought I have been working on this car for about a year. The same gas is sitting in the tank and its just 87. The original motor was a 350 and my 455 is a 9 to 1 compression. Think the gas could be causing some issues too? Though it does idle just fine.

72 Olds Project

And not sure if I hate to say it, but this is one of the few project cars I have had where it will start immediately upon turning the key. It is great, but I read that was bad for your motor because the oil is not moving. A little starter turn then fire is the recommended I guess?

Bill in NC

For an engine that is going to sit for a while at times, I guess you would want it to prime a little before firing, but I personally want my cars to fire immediately lol

Definitely need some fresh gas in that tank. Not knowing where your timing is set, I would throw some 93 in there and work your way down if you can. If it still has that problem after running for a while on 93, you may want to try a colder heat range spark plug.

We need to take a trip to Classic Olds. I have talked with him briefly at the AutoFair a couple of times and he has said a few times that I needed to come on up and see whats there. I think he said he was located right off of I-40.

72 Olds Project

Okay I will give that a try Bill. Bad thing is I was trying to empty the tank so I can pull the sender. haha It is bad

I agree...when it starts right up it just feels good.

You know I looked for his shop, but from the address I could not find him. I felt like I was stalking the guy. I never did call him. Is he still in business? I would like to find out too. That would be great to make a trip over!

Bill in NC

If it's not pinging while running, just keep running it till it's empty.

I don't know if that guy is still in business, it has been at least a year since I've seen his spot at the AutoFair, but at the same time I wasn't really looking either. I also have not been a member on here long enough to know if he is a member here.

72 Olds Project

Will do Bill!

It would be my luck if he is no longer in business. I just got this car a year ago and it needs lots of help. I am restoring it though a little at a time. She will never be perfect, but it should be a fun car.

When you say Autofair...are you talking about the one in Charlotte? Or do they have another one?

Bill in NC

Yes sir, the Charlotte AutoFair. I go every spring and fall. I got an invite this fall to show the 65 with the Mid Atlantic Olds Club.

coppercutlass

where is your dist. vac hooked up to? Sometimes that will cause that knock you speak of. I had a similar issue with my ebrock., my dist. vac was hooked up on the ported side and i had to crank the idle screw alot and when id shut it off it would want to run on i went to un ported full vac side i lowered the idle speed and it no longer wanted to studder after i shut it off ., also with holleys if you open the primaries alot to keep the idle up there will be a flat spot/bog that will never go away

72 Olds Project

You will have to tell me when you go Bill. I have only been once but that was a while ago. I was buying parts for my 66 Mustang I had, but don't tell anyone. LOL Congrats on the invite!

Hey Copper....I have running through the carb vacuum. I was told that is the best spot to run from. I could try the manifold and see. Is that where you are saying yours is at now? I probably need to get my hands on a vacuum gauge to check that part out as well. Thank you for the info!

coppercutlass

on a holley the full vacuum port is on the base of the carb dont run it off the manifold

72 Olds Project

Ahhhh! I need to look at this Copper. We hooked it up on a port that was top towards the air cleaner on the carb. Perhaps I am on the wrong port! That may have helped greatly Thank you! I will investigate tomorrow