$$$frumnuttin'

Got to get this dif installed this summer. My question is: does the tech II simply ask for the gear ratio to be entered thereby automatically adjusting the shift points, or....do they have to be entered for each gear...if so, how on earth do I know what to tell it?

Got uid0

lol I do not believe you have a tech II.

You can use any number of handheld programmer or have a tuner reprogram the new gear.

$$$frumnuttin'

you still didn't answer my question, but seem to know the answer....DOES THE TECH II SIMPLY ASK FOR GEAR RATIO THEN AUTOMATICALLY SET THE SHIFT POINTS AND THAT'S IT?:toet ap:

Bluefire

When I did the 2:73 to 3:42 swap I used HPTuners. As soon as I entered the new gear ratio, the HPT set automatically re-adjusted the shift points to a more aggressive setting. Of course, I wanted them set even more aggressively than that.

Hope that helps.

$$$frumnuttin'

thank you...also, I am wondering if my coilovers will be in the way...any idea on that? Finally, more aggressive means the car shifts sooner than with the 2:73, or at lower MPH; or do I have that backwords?

ajg1915

Hey Jerry,

Typically, you can take your car over to a dyno shop and have a tranny tune performed.

They set RPM shift points, line pressure, etc .... I had 3.42's with my maggie A4 combo and it was a blast to drive. Wish I never "F'd up the car with all of the other crap.

Lesson learned.The Tech2 is used mostly for setting stock specifications, tire size, options installed, etc .... HP turners or some other tunning software will give you a much broader range of control over the settings.

Bluefire

As far as shift point go, typically a more aggressive trans tune will move the shift points higher up on the MPH scale and RPM band.

$$$frumnuttin'

thanks Tony, I am starting to see the ramifications now. My thought was to have my chevy dealer install the thing, get the hard part out of the way, then drive it for a while as is...I was just concerned that the shift points were something I had to tell them what I wanted, but I have no idea what to tell them!

$$$frumnuttin'

Ok, thanks....so if I have the dealer do the install they won't do anything to the shift settings? Or, the Tech II will ask for the gear ratio, then make some sort of mild adjustment higher? As you can see I am having a tough time understanding where I want the car to shift once the swap is done....

ajg1915

Find a shop near you. I thought you were up in Michigan ? If you near Macomb area, I would look up Dr. Phil (aka Road Rebel).

Bluefire

I don't know exactly how the Tech II works but they (dealer) will use it to log the new gear ratio in your PCM. Tuning a trans is a VERY subjective and iterative process. It's all about how it feel to you during the conditions you drive in.

I'm still not relating to the "coilover in the way" question. Can you explain more?

$$$frumnuttin'

thanks....regarding the coilovers, I am a little concerned that the vette mechanic at a dealership might mess things up with being they are aftermarket suspension parts, so that is the only reason I ask because I know the wheel hubs etc need to swing away to pull the 2.73 out rearward, ...just want to cover all bases before turning the car over to a dealer, the guy is good and understands corvettes, but I will need to go over everything before I agree to have them do it....it is a GM part, so no problem there, just a lot of labor that is way more than I want to get into at this age... They are close to home, good friends, and trustworthy with my car. I'm looking simply for better pedal response, I do not race.

bumble-z

Those top two bolts, on your c/overs that you had so much fun with when you did your LG C/overs, will have to come out.
Along w/the two upper contoll arm bolts.

lionelhutz

The Tech2 will just reset the gear ratio which will allow it to shift properly. It will seem like it has more aggressive shifts because it will be easier to rev it higher and hit a higher rpm before shifting.

If the top bolts of the coilovers were a real pain to install then tell them to pull the lower bolt from the coilover when dropping the rear suspension. If they pull the lower bolt then make sure they torque it to 100ft-lbs and not the 157ft-lbs called for in one spot of the manual. You are confused how the differential comes out because the whole rear suspension must be removed to get it out.

Peter

$$$frumnuttin'

Thanks Bob, I was afraid of that (thanks LG!)...Bakers Sunday?

Here's one of them!!!! (behind the easy one)

$$$frumnuttin'

Peter, I hear ya...I was told by the tech that installed my headers that he would be able to pull the dif out rearward on my car because my center tub in the hatch area has been shortened by 4 inches. I did that in '98 when I installed a straight through exhaust for clearance. So, I would have to point that out to the chevy dealer mechanic and see if he agrees...make sense to you?...would save a lot of disassembly!

You can get an idea of the shortened tub here...note how much undercarriage shows (note the Jake skull)....the sway bar might be the only thing in the way once the driveline is tipped down for removal...then again, it's been a long time since I've read the procedure, and I probably have it all wrong...that's why I'm asking...

lionelhutz

I'd have to see it to know for sure but I still doubt it will come out without dropping the rear crossmember.

Peter

bumble-z

I'm w/you.