mrscott25

Dropped my new engine in and in the process of dialing in the carb.

I fired it up cold this morning and my choke took over as it should. The car is idling about 2400 RPM under full choke and kicks down appropriately when warm.

I have a choke idle speed adjustment on the carb but I am wondering what other cars are set to "high idle" at when cold. 2400 seems a bit high for a cold motor.

Any thoughts or suggestions?

claysmoker

Too high IMO. I use 1500 which is about what the factory used. At least that's what my feeble mind remembers. My engine is not stock by a long shot and runs cleanly at 1500.

Hpozzuoli

1500 is best. 2500 on a colder day isn't a good idea.

FireballXL5

Mine is in terrible need of a proper tuning...

Blip the throttle once, fires right up! Sits at 800tpm kinda sputtering all over itself... As it warms up 15-20 secs Rpms start to climb and she smooths out at 1300-1400... If I do nothing and let her continue to idle while she warms up further she will slowly climb up into the 2200-2400 range all by herself...

Once fully warmed and kicked down she sits at 600 rpm in neutral... 500 rpm in gear ... Typically I'll sit in the car as she warms up, and each time she gets to roughly 1500 rpm I'll give the throttle a little blip and she will kick to half choke etc... So , it requires me to stay sittin in the seat while she's warming up... Can't turn the key and walk away unless I want to come back to her sittin at the 2200-2400 rpm idle before kick down..

One other thing I've noticed, is after a cruise home from work roughly 25 miles ... When I pull into the driveway to unlock the gate, she's sitting at 800rpms in gear and 1000 Rpms in neutral... She doesn't necessarily sound like she's picked up that many Rpms, and it's fairly consistent... I wasn't sure if I needed to look into my tach further, or if it can all be solved with a proper tune up...

Btw , I'm running a 383 stroker , full stainless exhaust, and holly DP carb in my 81... So, some special needs/attention are in order ... But, like all vettes, it's a matter of only tackling one project at a time... Once warmed up she's a dream to drive and never dies at an idle... All will be tuned/repaired in due time.. ;-)

Flyinace3

350 with dart heads, 276 hyd roller cam, qjet.
1200 RPM full choke
750 warm idle

mrscott25

Sounds like the consensus is about 1500 or so.

Thanks, I will adjust it down.

Derrick Reynolds

Mine is about 1500 too. '70 454 with Holley double pumper carb.

4SPDL81

E4ME on my '81 fast idles at 2000RPM...( the book spec is 2200RPM...which seems a little high to me....)

7T1vette

The normal method of setting Hi choke rpm is to first get the engine warmed up. Then, position the throttle so it is on the proper step of the choke cam and start engine (without messing with the throttle). Adjust the 'fast idle' rpm to manual specs (usually something around 1300-1500 when engine is WARM).

With the engine cold, one full application of the accelerator pedal should actuate the choke [properly] and allow the engine to start and run easily at something around 1000 rpm until it warms up a bit. If you just started it and let it idle, eventually the engine would reach the rpm you established with a warm engine.

FireballXL5

Problem with that for me, at least til I dive further into tuning, is that is not enough throttle to keep my engine running while fully cold...

Perhaps the carb needs adjustment... Or it is a quirk associated with this motor and how burly it's built... I'm hoping it's just out of carb adjustment... ;-)

Dyno tune in my future as time and $$$ allow

wow

At least you got the feeble part right...

claysmoker

I take after you bubba.

Have you heard from the man who bought your toy? Or have you heard from his attorney?

Paul L

I set mine at 1,400rpm.

wow

Yeah I did hear from him, and...
he decided to send me even more money because of all the work I did on that spare tire tub, and...
your check is in the mail, and...

lars

That's way too high. The carbs I build are set up and tested at 1150 - 1300 rpm, depending on the application (1150 on a 4-speed car, and 1300 on an auto tranny). 1350 would be my upper limit. The rpm will vary slightly with temperature.

Lars

claysmoker

Yeah. Right. Why don't you go back to C6 where you belong you traitor?

I'd say we missed you at HAN, but then I never lie.......much.

wow

I didn't think they let kit cars in HAN?

claysmoker

I made mine from a kit!

Seriously, missed seeing you and Debbie up there. Hope you guys are enjoying the C6. I'm jealous!

doorgunner

In case anyone missed it the 1st time.

wow

Don't forget we still owe you and your wife a dinner. Got a favorite place in Hooterville (besides McDonalds) (and sushi...NO sushi) where we can meet up?