Just picked up a 350 TPI 89' Iroc that needs a transmission. I have a line on one from an 84 305 Camaro, obviously not a TPI car. In terms of mounting and internals, are there any reasons why it won't work with my car?

 

Externally they're close enough to interchange. Just make sure all the parts from torque converter on back are from the same set. When you get into the internal parts, the 84 trans won't have the aux valve body and some of the smaller parts. As a rule the later trans usually work better, not that there was anything wrong with the 700R4 in my 83 Camaro, it was just not nearly as refined as my 87 and later cars.

 

So paired with a TPI 350, I'd probably feel like I'm lacking a bit from a correct year 700R4? Maybe it's better to hold off for a sec and find a proper one.

 

if you're going to spend any money on the 84 tranny I'd wait for a '88 up one. the later ones display incremental improvements, especially the addition of the auxiliary valve body. '87 was the transition year so it may or may not have the AVB.

one from a sportier model (Z/TA/Vette) will likely come with a better calibrated governor.

when you replace the TC the sportier model TCs should be looser (who knows what you'll actually get as a replacement though). a common upgrade used to be the S10 V6 TC.

 

A big part of me is considering a T56 with the 350, but with my inexperience, I don't want the car to end up sitting idle for too long while I figure everything out. I'll keep on the hunt for an 87+ 700R4 so I can have the car driving at least. Say I were to have the current one rebuilt, would it run me around 1200, or north of 2k? The used 700's around me are around 500, but of course that comes with the mystery of whether or not it's functional

 

IIRC, because it's been 20 years since I had my 83, the early 700R4 liked to hit hard when shifting from park or neutral into gear. I don't remember it constantly kicking in and out of lock-up or OD, but just in general it was a bit more clunky. The 700R4 in my 87 is better, but tends to shift harder than all my 91s. Just from behind the steering wheel, the later 700R4s seem to be a lot more civilized without giving up much if anything in the way of performance. It's hard to quantify, but you can tell the difference.

Some of the upgrades can be implemented on the earlier transmissions, but really I'd try to start with as late a 700r4 as possible.

 

Are there any changes between ones tied to a 305 or 350? Or am I safe either way?

 

I recently swapped from early (originally 86, then an 83 or 84 that was "built") without the aux valve body to a 92 Z28 700R4 that was built by Ligenfelter. Can confirm it has much better manners - shifts softly into drive and reverse at idle, kicks down faster, and generally has much better manners.

GD

 

Without digging deep into the part catalogs and checking, I'd assume (educated guess) that there are probably minor details that would have originally been specific for optimal results, but at this point, I wouldn't lose a bit of sleep over that small a difference. You can change the governor, or the boost valve, servo, tv valve, blah blah. The differences between the calibration and internal parts will be a lot bigger for something like comparing a 4.3 Asstro Van 700R4 to one from any thirdgen. Once one has been rebuilt, who knows what parts from what 90* GM engine donor may have carried over or been exchanged with whatever random part from the spares bin. Ya know what I mean? A rebuilder doesn't necessarily care if a core was from a Corvette or a 4.3L asstro van.

 

Early '84 700s were 27 spline converter,mid '84 and up 30 spline.I have 8-84 build 700 in my car and it has been very good.

 

^^^^This^^^^ I get fuzzy on keeping exact year change-overs straight when you get back too far from my core focus of interest (1991s). But this is why I said make sure the torque converter on back are all from the same donor.

 

Scored a 700R4 from an 89 350 GTA with nice km, so I think we're all good. Now I'm just trying to get the car to run

 

Hahaha You've just made the CLASSIC car project mistake! You've acquired a part you weren't ready for yet! *Maniacal Evil Mastermind Laugh*... Oooh! I think UPS just dropped off the upholstery for my Project Firebird that's not even in primer yet!

 

Hey now it's better than getting that bumping stereo system in a car with no motor At least I got it running today, so I can sorta justify the stockpile of parts I've been collecting

 

It's OK, I went out and tugged a basket case Firebird home, just for the shell, so I would have something to bolt my stash of parts into. It's not just a forum for advice and tech problems, it's also a support group.