Competition Launching in 4x4 ?

[GIT-R-DONE]

Drag racing, your at the line, are we in 4 wheel drive or 2 wheel drive? Feather the clutch, get er rolling and then get on it, or go all out in 4 wheel? can you cause any damage to the transfer case at high speed, or would you lose HP and speed by running in 4 wheel? Anybody ?

 

[Pit Bull]

Watched Katdiesel run at KCIR raceway in KCMO. He would launch in 4x4 and then shift to 2wd part way down the track. His was an automatic.

 

[mcoleman]

You can shift them out of 4X4 going down the track but the transfer case won't release until you lift off the thottle. I would just leave it in until you cross the finish line then shift out before you try to slow down and turn off on the return road. Be careful with how much boost you build if you are running a stock input shaft. That is if you want to keep the stock input shaft.

 

[jstyer]

Leave it in

Ran 9 hard runs at MIR all the way in 4wd. The 6 speed is a *itch to run with though. Had problems keeping boost after dropping clutch at start. Must be a trick I missed. Didn't appear to do any damage and at 85 mph when hitting traps was still manageable in 4WD. Shifted out as I slowed down.

 

[KatDiesel]

Originally posted by mcoleman

You can shift them out of 4X4 going down the track but the transfer case won't release until you lift off the thottle. I would just leave it in until you cross the finish line then shift out before you try to slow down and turn off on the return road. Be careful with how much boost you build if you are running a stock input shaft. That is if you want to keep the stock input shaft.

Transfer case will, but the axle will not. There is a big difference in running 4wd the whole way vs shifting out, you can "feel" it. I shift out of 4wd before the 2/3 shift takes place. And its the output shaft that will snap first generally if you build too much boost. But he has a 02 so its a different story on the shifting out of 4wd.

 

[Rhondasway]

I always launch in 4WD, and shift out as soon as I'm in 3rd. It doesn't seem to have made a lot of difference as far as ET's, but may be a bit faster and probably wears less on the trans case.

I pre-stage, build almost 20lbs boost, finish staging, then go.

CAUTION: Don't do this unless you plan to replace your output shaft!! I broke mine staging, but have upgraded to a billet output (already had the billet input) with no problems since. I'm currently running about 450HP, but broke my output with about 410... I recommend upgrading before breaking to avoid being stranded!

I've got at least 150+ 4x4 launches with no trans case probs (she said while knocking on wood ).

 

[GIT-R-DONE]

So tell me , what output shaft are we talking about, trans or transfer case? Sorry, but I want to make sure I know what your talking about. thanks

 

[Idaho CTD]

The transmission output shaft is the weak link next to the input shaft also in the transmission.

 

[GIT-R-DONE]

So, were does a person get these billet input/output shafts at?

 

[Idaho CTD]

DTT and Suncoast have them. I dont know about the other transmission shops.

 

[mcoleman]

Goerend also has them.

 

[MCummings]

Just broke my case. Details tomorrow



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=81515



Merrick Cummings Jr

 

[01_HO]

At the line hold the brake and throttle with your right foot and slip the clutch to build boost. You will have to practice your starts to see how much fuel you need to keep the charger lit when leaving the tree. You could try to engage the parking brake instead of the two pedals with the right foot procedure. I've never tried the parking brake just heard about it, so try with caution there maybe carnage involved.



lol, Jeremy

13. 3 @101 six speed, B1 and #2 only

 

[Snow man]

cuda, are you aunching your 6speed? There is no sense tellling you what breaks on an auto,if your launching your 6 speed. If your launching your 6 speed, be prepared to buy a clutch if your going to get the most out of the truck. Im sure you know drag racing is tough on parts,expect to break something,especially on a standard,you shock load the axles,u joints,and t case.

 

[Pit Bull]

Originally posted by 01_HO



13. 3 @101 six speed, B1 and #2 only

Wow, you did that with a six speed? How did you get it to shift that fast? Everybody beats me from the stop light with my six speed. I only start to catch/pass them when we get up to speed and in the 45-70 zone. I thought the six speeds were dogs for the first 0-45 mph? Very impressive

 

[Snow man]

I agree that time with a 6 speed is awesome,I suspect the driver really knows how to bang gears,and like he said he abuses the clutch to light the turbo coming out of the hole. I wonder if he skips gears at all,since 3rd and 4th are close.

 

[Scot]

So how tolerant is a NV4500 of slapping gears?

 

[turbo lcc]

Pit Bull,



here check it out for your self ( 01_HO's race )



http://www.caldwellonline.net/Dodgediesel.wmv

 

[RKohn]

There's a spot on my daily drive that I routinely launch in 4X4. Coming out of town on the business loop (4 lane divided) there's 2 left turn lanes and a stop before crossing the oncoming lanes. It's about a quarter mile past the stop before the lanes merge into one. It's slightly uphill and the left lane always has some loose dirt, so if you don't launch in 4 wheel from the left lane, you just make a lot of smoke and noise. Otherwise, it's Stangs and ricers in the rearview.





Oo. Oo. Oo.

 

[mcoleman]

Pit I think 01Ho had said that he launched in 3rd with the tires spinning and banged gears the rest of the way down the track. he is making some major HP. I wish he would make it down here to Rogersville some night and wake up the Ford boys. I can't afford the new transmission right now so I'm staying away from the track and keeping the comp unhooked.