MS4 Tuning with HPtuners ?

Reply Subscribe

Thread Tools

Search this Thread

Sep 30, 2009 | 05:57 AM

Z06Frank

Thread Starter

Teching In

Joined: Aug 2009

Posts: 31

Likes: 1

From: Shediac,NB Canada

MS4 Tuning with HPtuners ?

Hi, me and my tuner are having problems setting my 02 Vette with HPTuners problems and mods listed below. Willing to send my base or modified map to someone who tunes allot of these cars. All the problems are realy all under 2000RPM it runs the very best at WOT.

Problems:

Bucks between 1500rpm to 2000rpm.
Idle will drop to 500rpm at stop light then shoot up to around 1500rpm then idle will stabilize.

Part List:

Texas Speed MS4 Cam 239/242, .649"/.609" 111LSA
FAST 90mm Intake Manifold
LS2 90mm Throttle Body
FAST #36 Injectors
LG Motorsport pro longtube headers
B&B Bullet Exhaust
Powerbond 25% underdrive pulley
Halltech Stinger CAI

Last edited by Z06Frank; Sep 30, 2009 at 07:34 AM.

Sep 30, 2009 | 08:58 AM

SSpdDmon

TECH Addict

iTrader: (10)

Joined: Jun 2004

Posts: 2,918

Likes: 0

From: Commerce Twp, MI

Quote:

Originally Posted by Z06Frank

Bucking - Sounds like it has too much timing and may be too lean down low. Suggest lowering the timing and increasing the O2 switch points to richen it up (assuming it's still running in closed loop).

You can control idle drop with throttle cracker/follower and timing. I give some hints how in my sticky over at EFI Live. The same tables are available in HPT.

http://forum.efilive.com/showthread.php?t=4661

Oct 1, 2009 | 04:43 AM

Z06Frank

Thread Starter

Teching In

Joined: Aug 2009

Posts: 31

Likes: 1

From: Shediac,NB Canada

I have my stock map and the map that my tuner worked on if I upload them here can someone look at them ?

Oct 1, 2009 | 05:47 AM

Gordon0652

TECH Junkie

iTrader: (4)

Joined: Sep 2006

Posts: 3,188

Likes: 2

Last year i tried tuning my MS4 with EFIlive... Took me all winter on my dyno and still i could not do it.
Maybe you will have better luck!

Oct 1, 2009 | 07:01 AM

nikon1999

10 Second Club

iTrader: (22)

Joined: Jul 2003

Posts: 1,290

Likes: 14

From: Wellesley, MA

definitely timing issue with the bucking most likely. The coming back to idle sounds like the raf needs to be dialed in. What are iac counts?

Where i would start

Reply Subscribe