blackcats56

Just built an L33 and swapped it in place of an lm7 in my avalanche. Its running a 216/220 cam with 560 lift @ .050, 114 lobe sep and ported 799s with a radius cut. Lifter pre-load set to ~ .045 Its about a full point higher in compressoin than the lm7 at ~10.5:1 and it is untuned but being a fairly mild build I'm wondering if this thing should be able to idle on its own or not?

Has long tubes and throwing a corsa on today so I can get it tuned but need to make sure there inst something else going on first.
Thanks

redtan

iTrader: (5)

Even though it's a relatively mild build, I still don't see it idling at the stock RPM that the auto commands.

If it was a manual and/or higher RPM stock idle it will struggle but eventually it should at least idle. Not so much on the auto tune which has considerably less RPM at idle.

For example, my car stock idles at 550 with the auto and I believe 700 or 750 with a manual. When I did the heads/cam, one of the first things I did to the tune is just raise idle to 800 before doing any of the fueling/air changes. It idled but barely. I can't imagine that thing trying to idle at the 550 that the stock tuned commanded.

blackcats56

Thanks redtan, that makes perfect sense. I didn't even take that into consideration. Thats exactly what's going on. Hopefully it doesn't surge to bad when in drive, might have to stall it