Chevy 454 into J-truck

[Joe J-Truck]

I know 350 swaps are common, anyone ever done a bigblock? I want to use a 700r4 behind it and ??? transfercase to work with the m175a axles. The pumpkin on the front D60 is passenger side. I'd like to avoid trick adapters. 2much$$$!
I'd also like to hear opinons on engine mount kits/fabrications and exhaust options..
thanks everyone for your input on all my crazy ideas! :D

[Jake_S]

The best way to make the swap easy is to get a donor truck with the drivetrain that you want. This will make it easy for you to see how it will fit under the Jeep, and where you might have clearence problems. It also keeps the cost down, plus you'll already have a set of dshafts that you can get either lenghthened or shortened. You'll probably need a custom set of headers made, I have only seen SBC headers offered for our trucks. Besides that, the swap will be the same as doing a SBC.
Jake_S

[Snakeyes_Tx]

Why in the world would you want to use Vintage Dana 60's and Dana 70's from an M-715 with drum brakes and 6 on 7 1/2" bolt pattern???

[64Trvlr]

I agree with Snake why would you want an old obsolete set of axles when you can have a D60 and Corp 14 bolt? I like the rest of your swap but this isn't the best idea I've heard. The BBC is just as easy to swap as the SBC.
:cool:

[Snakeyes_Tx]

<BLOCKQUOTE>quote:</font><HR> The BBC is just as easy to swap as the SBC. <HR></BLOCKQUOTE>

...just a WHOLE lot heavier! :eek: :D

[Stuka]

You will need a body lift to fit the big block AFAIK...and remove the heater box too I think. Not 100% sure on that tho.

[71JEEP]

fitting the bbc in a j-truck you have to make room around the heaterbox, that is the only big hurdel, other than keeping it cool, need a v-8 radiator support and a aluminum radiator worked in my truck.
rod

[mark]

im putting a 502 in my chero.we are fabbing everything.

[Unknown Jeep]

Joe,
It has been done... George Andrews in AZ has a 454 in a Cherokee.

You must lift the body to get the heater box and Brake booster above the Valve covers. but yes it will fit. (you need a Huge shoe horn) You must pull both the heater and the booster to put the motor in, then re-install. Power is Stunning, and the sound is cool too.... George went with a late model EFI setup.. Computer and all... TH400.

The TH 700R4 will never hold up to the Torque out put of the 454... (trannys are rated for how much TQ they can handle) If you go to GM's Web site you can get the ratings of all those trannys (in the race parts area of the web site.)GM has only two trannys rated for BB power.. the TH400 and the TH4L80E (case is based on the TH400) the input shaft of the TH350, TH700R4, and the TH4L60E are all SMALL and will twist up when heavy TQ are put to them.

I am thinking about a TH700R4 set up for my SBC but only one that is built. If you want TQ with out all the weight then you should be thinking about the chevy 400.. lighter and tons of lowend torque.... Yes I know..plenty of storys about over heating problems...but that is from those who don't build them right... I have two guys here who have 400's in Race cars... they never over heat them in HOT FLA WEATHER.

If I build up a 400SBC I will back it with a Th400 (that I have) or a TH4l80E (that needs electronic control box that you can get aftermarket... Look in PAW book)

If you want to know what transfercase fits what Chevy tranny I have all that info and can share it with you if you need it. (I have all the Gear numbers for all the trannys and the transfercases that chevy has used in Fullsize P/U trucks from the 60's up to today too.)

The new stuff out there needs too much computer control to make the swap easy, but it can be done. I can tell you how to make the TQ converter lock up on the TH700R4 with out forking out the big bucks for the kits they sell. I have the part numbers in a book around here for the right Switch to put in the valve body to make it work.

Troy
Elf in Tampa

[gbarrett]

Hey Unknown Jeep,

I'm almost being forced into a Chevy swap. I haven't decided on the 350 or 400 though. Could you post or email the info on the transfer case. I'm looking at the TH400 tranny as that is what my buddy at the machine shop has laying around. Am I going to have to do a front axle swap or is there a case (or adapter) I need to find?

Thanks,

Greg

[Snakeyes_Tx]

An NP241C will work, but then you have to deal with that darn slip-yoke. I think the easiest thing to do is to take the input gear from a 208C or a 241C and put it in your 229. It should be the same with just the different input spline count. That's how people use 700R4's with their 208's.. just swap in a 208C's input gear. Done deal, voila! smile.gif

[Jake_S]

GBarrett, why don't you swap in a chevy front axle? You'll get the instant spring over, they're cheap and plentiful, and the steering fix will only cost about $150 for everything.
Jake_S

[Cecil14]

I'm not real experienced here, but if you're going with a 454 I'd use a TH400 backed by an NP205. Personally I don't know how long a chain driven case will stand up to the torque that motor's gonna kick out. May not be a problem at all. But running 44's too I'd definently look into a gear driven case of one kind or another.

Just my thoughts,
Anthony

[Joe J-Truck]

Thanks for all the info.
So how much do I have to lift the body to make the 454 work? Are any bodylift brands better than others?
I know everyone likes the chevy Dana60 front, but I cannot find one for under a grand! All the chevy guys are willing to pay big bucks I guess.
I got a killer deal on the m715 axles so I'm grabbing 'em. Maybe I'm crazy, but I'll be dealing with drum brakes (may be fabbing in discs later), fabbing perches (I'll take the opportunity to go springover anyway) and the funky bolt pattern (either weld and redrill the axles and drums to change the pattern or use custom wheels). I figure its worth the hassle since they're already loaded with 5.88 gears. That's why I want to go OD on the trans.
I'd love to find a 4l80e, but I already have a 700r4 so it would behoove me to use it. I heard a Fairbanks racing rebuild kit will make a 700r4 good for up to 500hp and am considering that.
I'm now searching for a chevy np205 case. I understand these are the most burly and will bolt up to a GM trans with minor mods.
That 700r input shaft thing worries me, though. Maybe there's an HD one for racing apps.
What about chevy into FSJ motor mounts...
Any suggestions and/or comments regarding this crazy project are appreciated!

[Unknown Jeep]

Watch out with swapping Transfercases around on Gm Trannys... there are two 205's two 208's and two 203's.. depends on what tranny they came off from... Output spline count is one of the major difference. You can always go QT if you have a TH400... The QT will hold up for a good long time with the TQ of the BB. Ask George Andrews in Phoenix.

options for the TH400 are... Dana 20, NP208, NP203, NP205, and QT.
Dana 20 low range is 2.03
NP208 low range is 2.61
NP203 low range is 2.03
NP205 low range is 1.96
QT/lo Low range is 2.57
NP241 low range is 2.70 (2.60 in a suburb)
TH400 1st gear is 2.48
TH350 1st gear is 2.52
TH700r4/4l60E is 3.06

TH400/208 gives you a 6.47 low
350/208 gives you a 6.57
700/208 gives you a 7.98
700/241 gives you a 6.74

But behind a BB or a high power motor only the TH400 will last unless you dump $$ into the Tranny. A hint on the QT.. they used the QT in Almost Stock form in the late 70's behind 600 HP race motors... Start with a new chain and keep an eye on the slack.

Troy
Elf in Tampa

[bentpushrod]

With the driver side drop have you considered running Ford power? A 460/C6/NP205 would be sweet. Plus you could retain your front 44. Or look for a Ford Dana 60 front, which has the driver drop.

For the rear you could use a 60 or even the Sterling 10.25, which is a very tough axle.

Gbarret, a EFI 5.8 Ford (351) would be sweet in that pretty red wag of yours. Find a half ton donor truck, use the engine, tranny, t-case. That way you could retain your axles, just have to build new drivelines. Plus the E40D tranny would be sweet with the overdrive.

With the Ford engines no problems with distributor to firewall interference like the gm's.

[Unknown Jeep]

if you want to Swap to Dodge you can run a 360/727/NP208D pass side diff. It is a flanged output instead of the Slip yoke like the Chevy is...

Troy
Elf in Tampa :cool:

[Joe J-Truck]

Unknown,
Interesting info on the low range ratio of all those cases, So which cases outta what trucks could I use behind that 700r4 (I'll beef it up to take the BBC's grunt) to work with pass side drop Dana60 m715 front?

[Unknown Jeep]

Joe,
Pickups, Blasers and Burbs
Half ton
Mid 70 look for Dana 20's, Mid 80 Look for 208's mid 90's look for the 241 (driverside drop)
3/4 ton and up
look for 203's and 205's

Most 203's mostly fit Th400 (huge nasty thing, can be made part time 4WD and cool twin stick option) but there are a few of the 203/350's out there Look for different spline counts and there is a short input and the long input...Not easy to mateup to the TH700R4

The QT is almost impossible to mate up to the 700R4

The 205 was put behind the 350 and the 400, you need to makes sure it is the right spline count. The 350 spline count is the right one.

Dana 20 is a both Xcase... (jeep only used the TH400 version) not sure if you can mount it to a 700R4

208 GM used them lots in the 80's even mounted some up to the 700R4 near the end of it's run... most are mounted to 350's... nice shifting tranny but chain drive and alum case is somewhat weak for a BB

I guess you should look for a nice 205 Large Steel case, should bolt up and hold up... But they are getting harder to find as the Chevy boys think of them as the golden Xcase for their rigs.

AS for me, if I stick with my 350 I have options... TH400/208, th400/QT, Th400/dana 20 (EWWW) TH350/208, TH350/231, TH350/241 TH700R4/208, TH700R4/231, TH700R4/241.

If I build my 400 i will go with the Th400 solid but mate up a QT or a 208

Troy
Elf in Tampa smile.gif