Street/drag build

[Jaredpear]

I have a 1999 k2500 crewcab 4x4 original 454/4l80e combo. I want to build it into a turbo street/drag truck. This is purely a build idea list at the moment but I do plan on buying the turbo in the next month or so. Okay so starting with the engine. It’ll be a standard bore standard deck gen VI 454 with a scat complete forged rotating assembly, Merlin 320cc heads with 2.3 intake/1.88 exhaust valves and 119 cc chambers o ringed to the block. Lunati custom cam for the turbo and valvetrain with comp cams 1.7 full roller rockers. Edelbrock pro flo manifold (p/n 71363). I plan to use a megasquirt 3 stand-alone ecu. The turbo is gonna be a single BorgWarners500sx t6 flange 88/99 .085 ar, boosted to around 22-24 psi. The Transmisson is gonna be a built 4l80e manual valve body with trans brake. As for the transfer case that is one spot I do need genuine help in, how much horsepower can a np241 handle and is there any way to beef it up? Also does anyone have info on swapping a np242 into these? The fuel system is gonna be a aeromotive fuel cell with the eliminator pump running e85 through a -10an line to a t into 2 -8an lines to each fuel rail. Rear suspension is gonna be a trailing arm 4 link with a ballistic fab trussed 14 bolt and the front suspension is gonna be rebuilt stock suspension with custom dom tie rods and rcv axles. Possible coil over conversion for the front. I’m also thinking of running 295/65r15 mickey thompson Et r’s. Can they handle the weight? Will they be able to hook? I plan on pushing 1200hp on the strip and try to hit around 10’s. Interior will be 4 Corbeau seats 2 front 2 rear all 5 point harnesses and a rollcage. This is all purely idea and I haven’t even started yet and by no means will be done soon. I’d like to get anyone’s input on any part of this and see what everyone thinks?

 

[Christian Steffen]

Is the 242 supposed to be stronger than the 241? Perhaps if you search the offroading forums you can find a way to just beef up the 241. That would be easier than swapping in my opinion.

 

[Jaredpear]

Is the 242 supposed to be stronger than the 241? Perhaps if you search the offroading forums you can find a way to just beef up the 241. That would be easier than swapping in my opinion.

I’m not necessarily looking at the 242 for strength purposes all though it is quite strong. I was more looking at it for the full time 4wd aspect of it. What I’m trying to find out is if the Jeep 242 can be changed to the 32 spline Input and output (the mounting is the standard 6 bolt). It’d be nice to have 2wd for the street, full time 4wd for the track, and part time full wheel drive for snow and icy conditions.

 

[Christian Steffen]

I would imagine it is possible if you can find the part to do it.

Is auto 4wd worth that much work? Just my opinion here, but I have it in my 2014 Silverado and I've never used it. If the roads are ****, I just use 4wd.

 

[Christian Steffen]

http://www.novak-adapt.com/knowledge/transfer-cases/np242

If you really want it, i would get a used from an h2 hummer.

Look on car-part.com

There are some low mile options, but they're expensive.

 

[Jaredpear]

I was thinking about the hummer one but it doesn’t have the 2 wheel drive option. And you can upgrade the Jeep one with the hummer parts to make it just as strong. I found the input adapter to make it 32 spline from Novak https://www.novak-adapt.com/catalog/adapters/transmission-to-transfer-case/4l80e-to/kit-4l81 but I still am looking for the output adapter. And I believe it’s be nice to have the options. I used to have a 93 zj with the 242 in it and I loved it. I think it’d be worth it and it’d be less stressful on the whole assembly racing in full time 4wd then true 4wd

 

[Christian Steffen]

I would sure think there would be an output adapter if there is an input.

 

[Jaredpear]

Any other parts people wanna put input on? I wanna see what everyone thinks and maybe shine some light on something I’m not seeing or something that would be better?

 

[uncles93]

any updates or pics? do you have any plans for weight savings or weight transfer to the rear?

 

[TKerr]

If I was throwing this much to it I would build and beef the 241. If I was going to do a swap then I personally would go for an Atlas Transfer case for the money.
I can tell you from experience the transfer case would be less of o concern than the front end. I know from experience if you launch in 4wd on an IFS at a dragstrip it will not last or hold up.
From experience I had a 2005 with a built duramax and allison transmission pushing almost 1000 rwhp and I could not keep an IFS to hold up. I separated three front differentials and cracked one from a dig when launching. Countless bent, broken, and twisted CV axles.
Just an opinion, but I would do a solid axle swap. But that is just my opinion from past experience.
I am building a 600+ N/A engine for my truck and am going to keep the 1997 transfer case and beef it up.