the vacuum setup talked about above is needed so the tranny will shift automatically... if it is not there it will never shift from first however you can do it on the column...

 

But for a stockish aplication SBC a th350 would be more then enough... and plenty behind the 4.0.. plus there dime a dozen on cl

 

Correct - and I know I never said the THM350 sucked. Gawd knows how many of them I've built - most of which went behind 383ci stroker engines... (350ci block +0.030" + 400ci crank ~=383cid.)

It's just getting it mated to the AMC engine - since the bellhousing pattern is different, an adapter plate becomes necessary. Going with a transmission that already has the AMC bell pattern saves you so much work...

@huntingman - the THM700R4 was hydraulically and mechanically controlled, just like the THM350, THM400, THM425, THM180, THM200-4R, ...

The THM700R4 became the 4L60 ca. 1993, then got electronic controls ca. 1996 and became the 4L60E

The vacuum modulator you're referring to gave feedback on engine loading, and the kickdown was done with a cable linkage.

 

383 is a BEAST. Especially for the price you can do it for.
In my buds split bumper he's either goin the 383 stroker route, or the 377 destroked route. Havented decided which yet.

 

Go with the 383, he'll be happier. I've built dozens of the things.

It won't quite be the beast that those Hemis I built years back (punched out +0.060", offset ground crank - I think they finally came out somewhere just north of 500ci. Pop-up pistons pushed the CR up around 13:1 or so, and it wouldn't even idle on anything less than 100AKI...)

But, the 383 can be made a monster, responds well for forced induction, and is built using entirely COTS parts (although I'm sure the 377 is as well - what's that, a destroked SB400? Destroking and minor changes to valve timing can make a beast for turbocharging! Bear in mind that IRL engines usually run about a two-inch stroke...)

 

I am still up in the air on this, I have had a hard time finding a 727 or 999, but a 350th is easy

 

If your buddy wants a high rpm motor go 377... my 377 in my dirt car turns 8000 all day long

 

thats exactly what it is hoping that 72 split bumpers gonna be a beast. was thinking of going 383 with supercharger route.

 

Since the compressor is directly tied to engine speed, supercharging is a bit less work than turbocharging (in the planning stage anyhow.)

Next to no lag, boost at low RPM - and since you don't have to spin it quickly to make power, destroking isn't as much of an issue for supercharging as turbocharging (the reason that IRL engines run a two-inch stroke? 10Krpm with about 1.5atm of boost...)

If you want power at low RPM, it's easier to size a supercharger properly. If you want power at high RPM, it's easier to do with a turbocharger, I've found.

 

Ok anyone know if the 727 is vacuum controlled, or cable, and also if my NP231 will bolt to it...?

 

The A727 is a hydraulically-controlled box, generally shifted using a cable. I don't know what the transfer case mounting pattern is on the 4WD variants - but if you can source a donor for a 4WD A727, you'll probably get a better transfer case with it anyhow (the Jeep NP231 is fair-to-middlin', the NP231D or NP231C generally comes with a wider chain and often more planet gears. Getting a later 4WD A727 should allow you to net an NP241D, which is at least half again as strong as the NP231D or NP231C (wider chain, stronger gearsets.)

The 47RH/48RH is the A727 with the addition of an overdrive gear range, if you can find it (the A727 became the 37RH under the new naming system.) Given a choice, I would definitely prefer having the overdrive range available: go with a 47/48RH over the A727/37RH, or the 4L80 over the THM400/3L80 (I'd even go with a 1988-up THM700R4/4L60 over a THM350 in a lightweight rig, just for the overdrive gear.)

 

Well I can get a 727 4wd from an older wagoneer or a th350 4 wd from a 1980 3/4 ton both for almost nothing

 

Damn.....Kelly brings the knowledge!!