Big Blue24

Has anyone compared the differences in time between 4x4 1/4 mile and 2x4 1/4 mile? I'm wondering how much power the drive train robs when running the whole way in 4x4. To test one would need a consistent truck that can launch just as well in either 2 or 4x4. ie slicks and traction bars. or lower horse power so minimal wheel slip. I'd bet 4x4 robs at least .5 seconds in frictional losses down the strip.

paulb

I would guess that you are pretty close on your guess, but it would depend on how quick you run the 1/4 mile. The more hp, and quicker the E.T. the more effect the extra drag would have, or actually the more drag there would be. I would like to test it for you, but the problem is, that even if I leave at an idle, and the comp box off, it will still spin the tires after about the 60 foot mark, and continue to spin them until I lift.

John_P

Big Blue24:

DTR Member "paulb" has given you a good answer. I would add that myself and our "N.C./VA DTR Crew" do alot of drag racing down here and I am in the same situation as Paul,....that being, I absolutely cannot leave or start in
2WD with my 96' Dodge CTD, Ext Cab, LB 4X4 without totally going up in smoke!! I would say I would lose alot more than 1/2 second by leaving it in 2WD. I'll bet it would be 3-4 seconds. Back in October 06', I accidentally had my truck in 2WD even though the 4WD dash light was on. I did not have the transfer case shifter all the way engaged. I smoked the heck out of my tires at least to the 60' mark before I realized I wasn't going anywhere for some reason and let off the throttle!

As far as leaving the truck in 4WD, I may see a 1-2 tenth difference, but it is not as much as you would think on my truck. Some of our guys say they see no difference at all.

Hope this helps you some.

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John_P

Big Smoky

Well, you're gonna be a significant amount faster w/4wd launch because you're not spinning. I always reach down and shift it back down into 2wd around 3rd gear or so. On the '02's, the frontend is always locked anyways. All my runs have been 4wd launches. I haven't ran since I got the 64/14, but fastest time was 14.8 with all the same mods except with the stock turbo.

Eric

dzlfarmboy

A 2wd isn't gonna be able to shoot out of the hole not nearly as well as a 4x4 20psi launch. It might be close if your 2wd was heavily moded with slicks good suspension but even then i think those 4x4 walk em off the line.

TheBigNasty

Smoky is right, 02-up trucks will not make a difference because even in 2wd everything is spinning. I find it hard to believe that spinning a 30lb driveshaft is going to make a significant difference on these trucks, maybe on a ricer though!

Big Smoky

I agree. I really don't think it being engaged in 4wd is gonna make any differance at all.

silverbullet830

is there any limit to how fast you're supposed to drive in 4wd? i remember on my dads old truck he wasn't supposed to do more than like 55 with it turnin all 4.

rollinsmoke

Well I usta pop mine outa 4 wheel when drag racin but, it doesn't disengage till you let off the trottle so i just leave mine in the whole 1/4 mile run and i run 95 MPH

John DiMartino

The quicker the truck is,the more it loses in 2wd.My truck bone stock wasnt any slower in 2wd,probably faster.It wasnt until I added over 100hp,and a trans that i started having traction problems in 2wd.At around 350hp with a single wheel truck,4wd is much better ,if your less than 350 or have a dually you would need to experiment with your truck to find what works best,I know i can launch my dads 450HP 2wd dually very clean ,and almost keep with the 4wds out of the hole.My truck at 450p would just sit and spin....so it depends alot on your combination.