MeanWS6

Took my car to the track this weekend, with my new tranny/TC setup (see sig). At launch, the trans feels like it is holding back until it shifts into second and then it feels like a freight train hits ya from behind. I tried launching from different RPM’s and at idle, but was only cutting 1.8 60fts and a best time of 12.5 on motor and 11.5 with NXL 180shot.
I thought I was doing something wrong, so I had another guy take it down the track and you can definently tell when it shifts – car really wakes up and the rear end squats down. His impression was the same as mine – something is not shifting right, it feels like the trans is holding me back. He said it was bogging off the line pretty hard. A lot of the guys I talked too said with my mods I should be in the mid-high 10’s on spray and 11’s on motor. Raceweight was 3800lbs (convertible) and this was on slicks and skinnies.

Any thoughts? Could it be the 3600 stall? Or the trans?
(I have a video, so as soon as I can get it I will post it up so you can see)

Cheatin' Chad

iTrader: (3)

HEY! I knew I saw that car before. I saw you at Byron. You were running no times right? Parked next to a Vette w/ a cartek sticker on the back.

I hosted your "pressure drop" video

I was the plain jane silver T/A w/16 inch stock wheels running 11's on the gas.

TCI 3500
NX wet 150
BFG DRs 255/50/16
Free mods
Lid
Cut-out
=11.67@114.8 w/1.69 60'

That being said I think you should be going quite a bit quicker than me considering your mods.

Have you done any logging? A-tap or Hptuners?
Plan on going back to Byron soon? If so I can hook up my laptop and log some of your runs.

MeanWS6

yea - that was me and my friend Rich. My uncle came in from Michigan with his Vette also. Should have said something!!!
I have another vid of what the car is doing, I will PM you when I get it downloaded into my PC from my camcorder. It bogs hard, then hauls *** once it shifts.

silverTA

does do that on spary and NA runs or just spray

if it was just with spary,, something wrong with ur nitrous set up

Cheatin' Chad

iTrader: (3)

I would have had I put things together. I saw your plate. I even walked up to the cars where you guys were parked and looked at your engine set-ups....

Defintely PM me with the Vid. I'll host it for you if you want.

Have you had any tuning done? Who did it?

Cheatin' Chad

iTrader: (3)

Any logs at all?

MeanWS6

does it on both, NA and spray

Chad - Should get the vid tmr for ya!!! Working with speed inc to get a TH400 before the end of the season. I am tired of this 4L60e crap, but I do a lot of driving to and from Michigan so I am concerned about highway speeds with a TH400.

C4VetteLS1

I thought i posted here but i appears it didnt show up.

I had the same exact problem as you where it feels like 1st is holding back.
What it is, is that somethings not sealed in the valvebody right, allowing pressure to apply the 3rd gear clutch and the 1st gear clutches at same time. It makes it feel like the car partially has the brakes on or is "pushing" against you.

We pulled the valve body and fixed it (this was on a fresh race trans)

Pro Stock John

iTrader: (34)

Have a pro drive the car and assess. Maybe something is wrong with the valvebody as suggested. You should at least go high 10's on the gun with the PY3600.

Pro Stock John

iTrader: (34)

I went 11.0's many many times just on motor with FLP level IV 4L60E and Yank 4400TPE. 1.4's and 1.5's on 26's and 28's. 4L60E's can work fine.

rickou812

iTrader: (10)

You can test it by trying this.
Put you tranny in manual 1(first gear on the selector)
You can try this on grass or pavement.
If you tranny is ok it should feel like normal first gear.
If your tranny is messed up you can feel a definate drag and when you left off the gas it will feel like you are applying the brake...the car will come to a sudden stop. if on grass the rear tires will actually lock up.
You do not need to romp on it just ease off to about 10 mph and let off gas, as above if it cost freely look for other problems like pinion angle.
If it drags it means you band is engaged, this could be the result of the servo pin being to long or a wrarped sunshell or incorrect valving.
hope this helps.