jeremys

OK I did a search and I didn't find my answers.

I know Parish has 4WD and some others but it seems most have 2WD. I heard that 4WD makes for a good launch but do you shift back into 2WD after the launch or keep it in 4 for the rest of the run? Also on some auto cars people shift manually when making a run. Is it the same w/ your trucks? Or do you let the auto tranny shift itself?

Do you feel 4WD is better or is it not worth the extra cost/weight?

Also, if someone had a 4WD but wanted to swap trannies, is there 4WD components that would have to be swapped also?

James B.

iTrader: (1)

If the point is racing 4WD is a waste. 4x4 makes for a good launch in rain, or on crappy tires, that's it. At some point the power gets high enough the front end becomes too light to do anything anyway. Not sure how autotrac would behave. That is a slip-sensing system.
If you really want to lauch hard and get down the track fastest the best way to do it is to install the biggest rearend you're willing to afford and overcome the technical obstacles of. That should have a limited-slip differential. Tires can make it all work or not.
Manually-shifting an auto is only done by people who have not taken the time to get theirs programmed correctly. The PCM/TCM can shift the transmission at the exactly optimum point consistently every time if it's programmed right. Manually shifting the 4L60-E under power like that is actually destructive due to overrun clutch release rates.

The only thing setting apart the 2WD and 4x4 version of the trans are the tailshaft and tailshaft housing on a 4L60-E, or additionally the rear VSS and oiling orfice on the 4L80-E.

parish8

iTrader: (6)

i kind of agree with james, if the ONLY thing you do with your truck is take it to the track then 2wd would be better. if you like to have fun on the streets 4wd totaly kicks ***.

in order for 2wd to help you at the track you will have to run slicks and warm them up, most likey to run faster than i am running you will need a beefed up rear and a complete new suspension set up like a 4 link. i dont really know that much about all of that. hooking on the street could probably be done but you will at least need to warm up the tires and be on good pavement. haveing 4wd means you can race anytime you want. no tires to warm, just floor it.

i drive around in 4hi 24-7

KeukaZ71

i was going to say the same thing as parish. 2WD is better for the track.

but you've seen parish blow other rides away on the street with 4WD.

i love it for launches at stop lights, especailly if there is another truck or ricer next to me. the 4WD definitely helps out when you have a 3000 stall TC.

as for launching, i switch out of 4WD as soon as i can. usaully before the 1-2

F8L Z71

I wouldn't trade my 4wd for street fun...

I sit and think about how fast mu truck could be if it were one of these 4000lb 2wd regular cab trucks but with my combo on the street it would be spin city!!!! I would only be effective on the freeway which would suck.

At the track I would kick *** with a big set of slicks and some suspension tweeking but at what cost?

The 4wd works really well at the track and with minor adjustments it can handle quite a bit of power and still keep traction. I think Jim has found the limit

To answer your other question. In my experience at low power levels Auto Trac worked well to help you launch. After my big cam install and the converter I could no longer use it without the whole truck feeling like it was going to fall apart. So i started using 4wh Hi at launch and imediately stabbing the 2wd button. Worked well till I got the turbo. With the turbo it won't shift back to 2wd so I now run the 1/4mile in 4wd the whole way.

I'm sure I could be faster at the track without a 4X4 but when a STi or EVO8 pulls next to me at a light I have MUCH more confidence in a 4x4 than I would a 2wd on street tires.

parish8

iTrader: (6)

nicely said.

jeremys

thanks for all the input

moregrip

iTrader: (8)

a good driver makes up for alot, especially with 2wd
practice makes perfect.

F8L Z71

I drove:

87' GT with a 306ci S-Trim'd motor and 3500stall on Radial T/As (11.8 on those tires)

and

Nitrous/head/cam TA with a 4400stall for 2.5yrs remember? I know all about launch technique on the street.

So I know ALL about feathering the pedal or going up in smoke. Hahahaha

moregrip

iTrader: (8)

very cool