turbo87

I have a 04 Z06 with the LS7 conversion.It had a tune when the engine was built about 2500 miles ago. I just bought the car it is real hard to drive around town it wants to buck and jerk real bad, idle goes up and down sometimes but not always. but when you put the hammer to it runs great. the guy I bought it from bought it new and had DTE do all the work in and around 2011, but car has only been driven 2500 miles since. he said when they installed engine, dyno was 630 crank hp around 540 rwh.He doesn't remember it it was this bad at the start or not. He tried to get ahold of DTE and they have sold out since the work was done. Can it have to big of a cam to be easy to drive? Do I need another tune? cam is lift 608-596 dur 289-301 lobe sep 114. Thanks

appliance guy

Taking off at lower rpms can be tricky at times, but the surging rpms shouldn't be happening. I'm going through that right now with my build...surged like crazy after tune, I'm making them retune it. Properly tuned car should drive like any other car except for low rpms at take off.

turbo87

It's almost impossible to drive across the parking lot at slow speeds without pushing in the clutch every little bit, or it will jerk your teeth out. looks like I may put a stock cam back in it. If that's the way its gona drive.

appliance guy

You may need another tune, however in first gear going slow in a parking lot you will have to stay on the clutch and gas ....once you learn it, its not that bad.

tblu92

You can get by with a large cam far better with a manual trans than an automatic
That being said--there are too many unknowns to diagnose what your fixes may be--because of the retrofit of the LS7 into the LS6
Depends on so many things----Did the previous tuner use the existing ECM ? Did they make all the correct adjustments to accomodate the new LS7 ? Mainly--
The MAF---the T-Body---The injector sizing--Timing tables ??? Only an experienced tuner would be abl Oncee to sort it out--to see exactly what was missed or left undone-You absolutely need a new re-tune
PS:Once you begin to modify your engine it requires more maintenance then when it was stock--Even after just 2500 miles----- Valve train inspection--fuel trims--Knock retard etc

turbo87

Their is not many places in Kansas City Mo to get a tune. I been asking around and have found out very little Not sure what to do at this point.

0JDP Tech

That is actually a very common characteristic of a larger cam. Idling in first gear with no gas and no clutch is a thing of the past once you put a good size cam in. Its hard to say without seeing it in action, whether its a problem or a cam side effect.

All the best,

Jared Royce
801.545.4215

turbo87

Maybe I should go back with a stock cam.

CTD

Do you have duration spec's @ .050 or the cam card to post up. Overlap will be a good indicator of manners.

Square port heads are fussier on the intake side than cathedral's. You have a lot of good cam choices for that motor, make sure your tolerance for buck & surge is understood......mine is near zero.

Maybe poke around the C6 section try "Spinmonster" not sure if I have the spelling correct.

turbo87

Couldn't get the pic to post but @ .50 240-248 the box has LS1 3730R/3657R HR114+6

Mr. Jones

Looks a little big for street if you want easy low speed driving.
Check for air leaks in the intake system.
Any issues with PCV setup.
When the engine was changed the computer needs a calibration for the crank and cam position first before a tune. This is a learned timing process that requires a high end scan tool to initiate.
It only take about 5 minutes but this sets the sequence for fuel.
Are o2 sensors working? burnt wire on an o2 will get you.
o2 reports could be turned off and you would not get a light.

CTD

Miserable it is going to be @ 16* of overlap. Some claim they can make that drive like stock, no one has proven it to me.

I was 17* with a 416 stroker, you best have the side window rolled up or you are going to get pitch out. Lower gear's below 2k rpm hang on.

This is a very good thread if you want to get technical, the bad part is the originator Martin Smallwood, is no longer with Tick. So the name is incorrect.

http://ls1tech.com/forums/generation...-t-matter.html

Here is a link with cam shoot & square port heads, it's LS3 based not your bad a$$ LS7. A very good tuner told me overlap is overlap, displacement soaks up the big cam.....have not seen that either

http://www.superchevy.com/how-to/eng...ft-comparison/

tblu92

As I mentioned with a manual trans I have tuned much larger cams---A dyno tune does not help at all as all they do is run it up to WOT in 3rd gear and try to get the most HP there--only --they do not address any P/T driving--idle or start up parameters---Your cam is absolutely tunable with a tuner that does street driven tunes------I would not go back to a stock cam just find someone that is willing to spend the time doing a street or drive ability tune

turbo87

So i really do not need a dyno tune? Not worried about max HP ,It's a hand full the way it is.

95rtturbo

As was stated above by tblu92, for drivability issues, no, you do not.

turbo87

Well I found two places that do tuning about 45 min away. Called both, one place would not say much unless they have the car their,other was helpful and seemed to know a lot about tuning. But both said they would have to put it on dyno to find out what was going on before they could do and adjustments? Are they just saying that to get the 350.00?