Ultima GTR LS3 418ci Idle Questions

[doc350]

Hey guys,

I am in the process if getting an Ultima GTR up and running with a 418ci LS3 from Turn Key Engine Supply. I am having a hard time getting the idle to play nice in the car. The car will be idling fine, but then stumble and die when you depress the clutch or turn on the A/C.

The cam specs are "top secret" from Turn Key, but from the sound of it I would guess something in the 24x/25x on a 112 LSA. I have found that I have had to add a lot of startup and idle airflow to get the car to run. A lot, as in almost tripling the tables. Is this normal for a cam this large?

The other thing that I am curious about is the throttle pedal to throttle body relationship. Is there a way, other than the Throttle Reset function in the scanner, to recalibrate the pedal and TB? At idle, my TPS% is at 27. This seems a little high.

I have heard people say that you need to drill a hole in the TB, but I feel that this is a unacceptable way to address the issue.

I will post up a tune when I get a chance tonight.

Here is all the info I have on the setup:

LS3 based 418ci
Turn Key "Stage 3 Cam"
Turn Key "Stage 2 Heads"
LS7 Dry Sump Oiling System
Stock LS3 Injectors
Adjustable FPR set at 58psi.
E38 PCM
Idle speed set at 1100rpm, for now...

Thanks for any thoughts in advance.

[93camaro_zzz]

I agree with you. I am a firm supporter on never drilling a Throttle Blade. Mostly because you can never take it back. I especially wouldn't drill one on an DBW TB. Post up your tune please.

[JnJSpdShop]

I would never drill a hole in a DBW TB, old school cable driven is a different story with the drill bit