6.0 conversion IDLE PROBLEMS

[Yenko LS]

i love my LS engine,but if i drive spirited the idle will bobble up and down 3 times.Do i need to do a dyno tune to correct this ? It has a out of box tune from Howell. Other than that it runs awesome.i know this is vauge,just trying to find out how man guys how had a professional tune and if it fixed problems? THX Wes

[69MyWay]

After my live dyno tune - the results were amazing and immediate.

We did an article on it here:

http://mcspeed.homestead.com/Dyno-Tune.html

[Yenko LS]

Thanks.. i was looking for the push to get it tuned. One other question ,on conversions is anyone using a clutch switch and other than being a neutral safety does it relate anything to pcm for base idle or off idle problems? Thanks Wes

[69MyWay]

Thanks.. i was looking for the push to get it tuned. One other question ,on conversions is anyone using a clutch switch and other than being a neutral safety does it relate anything to pcm for base idle or off idle problems? Thanks Wes



Wes if you are running a stick shift it is crucial that you have a VSS hooked up if you want the best possible drive-ability from your machine. The PCM will look for speed to determine if you are at a stopped idle or if you are coasting. You can have stall problems without it.

On the clutch switch it is just plain smart to have that in there and avoid the car cranking in gear. Many of the wire harness systems go through that to make them work.

[Yenko LS]

Thanks for help! Yes i do have a neutral safety threw the tremac transmission.I also have the VSS wired and working. I just dont like the stumble and 1000 rpm base idle. Like your right up says i am happy with every thing else. THX Wes

[camcojb]

Sounds like the tuner will probably need to adjust the throttle follower tables. This determines how fast the IAC is allowed to shut down when the throttle is closed. Too fast will cause stalling or jumps in idle speed as the IAC catches the engine when the rpms drop fast. May also need to tweak how fast the IAC reacts, slow it down a bit. A good tuner will have that sorted out no problem, as well as setting your idle rpm.

[Yenko LS]

THANKS GUYS. This is why i come here. It is funny,the longer you drive these conversions the more you want them to be refined. Wes

[camcojb]

THANKS GUYS. This is why i come here. It is funny,the longer you drive these conversions the more you want them to be refined. Wes

that's the advantage of these late model EFI swaps; incredible power potential and when properly tuned can drive as smooth as your late model grocery getter.

[Mike Norris]

Good talking to you the other day Wes. Bring her down here and I will see what I can do for ya :D

Have a great weekend.

Mike Norris

[camcojb]

Good talking to you the other day Wes. Bring her down here and I will see what I can do for ya :D

Have a great weekend.

Mike Norris

Mike's the man! :hail:

[Yenko LS]

Well... you guys talked me into it. Im going to see Mike on the 17. I was goin g to Woodward dream cruise so I figuired i would go over and get it done. Should be awesome. I know the car has more in it!!! I am not looking for horsepower,im looking to fine tune the car. Wes

[camcojb]

I am not looking for horsepower,im looking to fine tune the car. Wes

pretty sure you'll get both! :thumbsup:

[WSSix]

It will be worth every penny. You can only do so much with a mail order tune. Heck you can get pretty damn good with a mail order tune from some of the good tuners out there. However, nothing beats a true dyno tune and street tune even from the good mail order guys. Every car is different and has its own personality. Mike will get it dialed in correctly.

[Yenko LS]

I am now getting more excitied about the dyno than my trip to Woodward Dream cruise?I will let you guys know how it goes. Should be great. Thanks Wes

[69MyWay]

By the way - you might want to make sure that your driveshaft is up to the challenge...AND that you have a loop.

The magazine article I cited was significantly delayed because I had done neither. I had a stock style 69 shaft that exploded on the dyno. Ripped the floor apart and cost plenty to get it back on-line to finish things up.

A quality shaft and loop really are not that expensive - cheap insurance.

You can youtube video and you'll see many such disasters that could have easily been avoided.

[Yenko LS]

Thanks for the tip. It has a Dennys Drive shaft and a loop at front. Our local race track makes us have both. And the bottom of the floor is painted,i have seen what a drive shaft does to the bottom of the car...not nice. Thanks again. Any thing else? Has any one done the drive from Detroit to Indiana? Wes