PDA

View Full Version : Motor Idle.



Danhercules
06-15-2005, 01:37 PM
I cleaned up my carbs this winter. Put everyting back where its suppost to be. I ran it on the trailer for a bit, (drive line not hooked up of course) and I truned up the idle way up. I ran the boat at about 2500, to let her run and warm her up, and just mess around in general.
I have a BBF 460, Bassets, tunnel ram, duel 750 DP's cam is 574/278 intake and 576/292 exhaust with 112 lobe separation, MSD pro billet with box. Timming at 34*.
My question, what should it idle at? I got her at about 900 RPM's. Should I be able to get it lower?

LakesOnly
06-15-2005, 02:50 PM
Motor will idle where it idles, there is no hard number...just smooth on all 8.
On paper, everything you posted makes sense to me, and under 1000 rpm is fine with your build.
Note: If the above rpm was with your boat on the trailer and your pump disonnected (as posted), you can bet that once the pump is reconnected and loaded with water after the boat is launched, idle will drop and you will need to raise it back up.
LO

SmokinLowriderSS
06-15-2005, 03:28 PM
Wherever it will idle smoothly and with resonable stability (not stalling all the time). On a mildly built performance engine, you ought to be able to go anywhere between 800 and 1,000 RPM. Taller cams with more overlap also make for higher idle requirements.

Danhercules
06-15-2005, 03:47 PM
Note: If the above rpm was with your boat on the trailer and your pump disonnected (as posted), you can bet that once the pump is reconnected and loaded with water after the boat is launched, idle will drop and you will need to raise it back up.
LO
I lowered it to 900 RPM on the water.
Thanks all. I just wanted to know if I should try to get it lower. Looks like its good where its at.

steelcomp
06-15-2005, 06:00 PM
With a flat tappet cam and higher than stock spring rates, the higher the idle, the better, on your valve train parts. I prefer ro not let a performance engine idle much less than 1K. Having it go lopety-lope may sound cool, but it's not cool. :coffeycup