Ok well I have a Holly 750 DP that runs OK. Living in MA, the temps and conditions are nuts up here. In the morning it can be 55 and my noon by 95. So granted my carb has a little trouble trying to stay on top of it all.

When I get up and start the car, it is really hard to keep it on. This is normal, the car has a HUGE cam. So I sit there count to 30 with the RPMs at 1500 and then I can drive off, sorta. It stumbles at the first light, then after 5 min, she idles at 850. So I turned it down a tinnnny bit to 700, and then things kinda drop down and she will stumble from time to time. So I went back up to 850. This seems high. It sometimes will get to 900 just sitting at a light. Kinda too high for me. I used to have this thing sitting in traffic at 650 RPM. What could be outta whack with the carb.

Things I chnged was the ignition, went from HEI to a CD ignition. Then I used to only have 6" vac, so I changed my PV to a 4.5 unit. That seemed to help. Now I can't get it to stabilise down low, so the pulls around 8" now. I really just want to get it to idle a little lower and be more stable.




Also, maybe this might help. Never happened before, but my car had a tinny bit of run-on when I went to get breakfast today. I turned it off, then it tunred over a couple times, and shut off. Might have been a fluke.

Either way i am going to get the car dyno tunned and the carb tunned later this month, I just wanted to have as much stuff squared away as possible and maybe give the shop a little help.

Thanks and sorry for the long post.

-Dennis

 

I assume you aren't using the choke.

 

Can you define "HUGE"? Depending on the camshaft, you may have to live with an 850 rpm idle. Everyone has their own preference, but I think you will find that a lot of people in the "big cam" club have an idle speed close to 850 rpms.

 

Yeah I hear that. I drove it to SUBWAY and the bank for over my lunch break and it had dropped down to around 750. So I guess everything is OK. Still seemed a little wierd that it is so all over the place. But might just be the different conditoins of the time of day and stuff. I dunno.

Yeah no choke at all. Still need to get rid of the damn flap though.

 

not that big of a cam IMO. I idle at 1200 when the motor is cold and then when it comes down it'll be 850/900 in gear. When the fans kick on then the alternator pulls the motor to 800, but by then the car is shaking and the motor isn't as happy. No reason on a bigger cam to not have it idle higher, some of my buddies cars are idling at 1500 with no issues, comes with the rpm range of the cam.

 

yeah, I see that. My car doesn't make power really till 2500-3000 area. But once it does it pulls real hard.

Hey, xpndbl3, you seem to know more about....everything. So I wanted to ask you....

Do you know what I should use to clean my intake and heads and timing cover?

I want them to look like they did when the car was new.



Just wondering if you knew some great way to do this. I will also post the Q in the detail and appearance section.

 

oven cleaner works well on aluminum, but will remove paint, so watch where you get it.

I usually steal whatever aerosol can my girlfriend has in her house and use that I think it's easy off oven cleaner or something like that.

 

Some oven cleaners will also remove aluminum.

 

remove aluminum? You mean like start trying to eat at it?

That sounds pretty harsh. Maybe I will try a little dab of my moms on the back of the intake and see what happens. Thanks, I would have never thought of oven cleaner.