mud racing 54/63 inch swaps

[the_experience03]

I'm looking to build my old dying 1984 short box into a mud racer to compete in the drags every weekend suring the summer. I've already started to find the parts that I need. I plan to run a 383 with 13:1 compression, Vortec heads, custom cam, Predator carb, etc etc etc....the motor works out to just under 500 hp, 500 ft lbs on Desktop Dyno.

Behind that I plan to put a Jeep sourced TH-400 (with Chevy bellhousing of course) and its Dana 20 t-case. This will all run down to a set of stock (yes, I said stock) 4.10 2 pinion axles with a well welded rear and hopefully a posi front (anyone got a carrier sitting around?). I'm still searching for a tire that I really like and comes at a price I can afford.

While I'm still 2 years away from making my first run, I do want to start thinking about suspension a little. I'm thinking that I want to run 54 inch stock chevy springs in the front. I will leave the axle in it's same relative location so that the stock steering will work (with dropped drag link and flipped balljoint on the arm atleast). This means I will need to extend the frame forward which is fine because this will then become my required integral high strength bumper. I figure my lift will come from how I mount the hangers while the bigger springs will work better to support the weight of the new engine. Anyone ever tried this and if so....what were the results?

For the rear I'm thinking about running the ever popular 63 inch springs. I've seen write up upon write up so I will not harass people with this except to find out if anyone has tried running Sky's kit. It seems like a real time saver, albeit a bit spendy. Any feedback would be great.


Oh yeah....one more thing....what specific headers have people run when doing this swap? I'd rather not pony up for a set of Downey or A.A. headers.....I'm cheap

Thanks in advance for helping out this TOR newbie

[rockcrawlintoy]

the_experience03 said:

Behind that I plan to put a j**p sourced TH-400 (with Chevy bellhousing of course) and its Dana 20 t-case. T

how are u goin to do that. teh th400 for a jeep does have have a removable bellhousing.

Drew

[the_experience03]

Well shit...I was under the impression that it does :-)) Oh well....the Dana 20 will still bolt to any 32 spline TH-400. I just like the idea of a nice short case with lots of strength, but without the weight of a 205 or the price or the adaptors to hook up a toyota 'case.

[94cnytoy]

eliminate the t-case all together.
built a 1-1 pillowblock/shaft/chain box.
you'll find out real quickly 500hp's nothin in the drag circuit and upgrade soon anyway.
the extra cost of a th400 won't be worth it either.
cheaper to stick with a th350.
the correct(straight cut gears) for the 400 are really expensive and that's just a part of the puzzle.
a used 2-wd(yes 2wd) th350 will last several runs and can be replaced for $50 at a u-pick yard on a whim.
hell, you could bring an extra or two with ya.
also for the steering axle, you may want to consider a full width 44 or 10blt. real easy to bolt together a 2-wd chev manual steering box setup.
spool the rear diff. lincoln lock won't hold it.
detriot the front(lock hubs on the line)
$8500 motor $500 drivetrain????

[the_experience03]

I see where you're coming from with the drivetrain points and you're very right, but the truth of the matter is that I'm racing in an Open Street and Super Stock class so some of the mods you are speaking of are outside the rules and feasibility. I'm still torn on the drivetrain. I'd like the power saving a TH-350 will offer, but lets face it....a 203 is no prize, nor is a slip yoke 208. A 205 would be fine, but heavy. The Dana 20 will allow an fairly easy swap without trying to hunt down all kinds of adaptors.

I'm really building a budget race truck to compete as a hobby. I don't expect to be REALLY competitive, but at the same time, Open Street was won several times last year by a Camper Special Chevy with nothing more than a welded front and rear and 34 inch LTB's.

My motor will actually be very cheap. I've done a fairly good job in my 20 years of developing networks that will allow me to build that 383 for $1500 with almost entirely new forged parts.....knowing Wissota racers is cool

If I ever decide to get more serious, I'll scrap this truck entirely and build a full rail with a 500 caddy (425 heads) burning alky and an appropriate amount of spray. Even the rails don't run chaindrives though....they mostly run glides with 241's (2.72 low gear=idling around the pits at a resonable speed).

I'm still at a loss for the front suspension though....anyone ever tried this with a Toyota (54 inch front swaps are common on Shitvies)?

At any rate, all input is very very much appreciated.

[the_experience03]

Also...one more thought on the TH-400 with straight cut gears....that's just a TH-475 and is easy to find under an older bus. Bus trannies are cool because schools like to take care of their stuff. The only problem is the output, but I guess that's just a swap away.

[the_experience03]

Also....one more thing (surprised I didn't get flamed....this must not be pirate). I meant 52 inch springs....sometimes the link between my brain and my fingers fails and they just do their own thing.

[94cnytoy]

well, put me down for one of those 500hp $1500 motors anyway.
what class are you setting up for?
That will prob determine the header thing.
The last 350-toy mud racing swap I saw had blackjack headers (2wd pu/auto) heated then bent to fit. The collecter was cut back 3'' to clear the trans.
(the racer I talked to is not internet friendly. he's a dairy farmer north of here)
when I asked him about front springs, he said "just unbolted/cut the front off the chevy, lined it up, blew somes holes, welded some tubes and was done"
lot's a detail there huh?
sorry my input's of no feasible use to you.

[the_experience03]

Thanks a lot. That was very useful. Gotta love redneck detail....surprised he didn't tell you what color rustoleum he used to paint the truck ;D

Anyway, as for class, I'm going to try and run both of those classes....My biggest concern is going to be trying to get 15 inches of vacuum out of an engine with .504 on both sides and duration to match

The other class is basically the same (most guys run both), but without a vacuum restriction and it allows full roller valvetrains.

If I happen to come across a guy with a complete forged 383 less the block (it became a motor in a Wissota Modified) sitting in the corner of his garage, I'll be sure to let you know. I was damn surprised to find someone willing to sell something like that for $500 in the first place. To my advantage also is that he works at a Chevy dealership as a mechanic....means access to cheap machining (he know people that know people that....well you get the picture) and a set of 906 Vortec heads that came off a Tahoe that got some fancy aluminum heads put on it.


Once again, thanks a lot ;D