bchapp

I am going to put in a WC T5 in my 1992 305 TBI RS Auto from a late 4th gen V6 car. Please don't ask why or try to talk me out of it because of the T5 strength. I am looking for some comments on specific areas of the swap. There is a lot of incorrect information about the T5 from the 4th gens on the f-body boards, and I have found the best information in the hotrod scene and this is what I have come up with. If anyone has first hand knowledge of the setup below, please let me know! Anyone actually done this swap?

The late 4th gens used the ford case. Hotrod Works sells an adapter that should work perfectly:
https://www.hotrodworks.com/product/...ssion-adapter/

This also adds enough space between the engine and transmission for the longer input shaft. I am a little concerned about driveshaft with the extra length. I am waiting on a response from Hotrod Works on the total added length of the setup, but 1/2" or so shouldn't be a problem, correct?

The late 4th gen V6 transmissions have a 26 spline input shaft so standard 3rd gen clutch, etc... will work fine.

I will use a 3rd gen bell housing (Holy Mary mother of whatever they are expensive...). Seems like there is no other way because of the transmission "lean" and the V6 having the odd-ball GM metric pattern.

The 4th gen uses a hydraulic throwout which I tentatively to reuse. Does anyone have comments on this? I also plan to use the 4th gen pedals and hydraulics so everything matches up.

I am concerned about VSS on the transmission, but some of the VSS adapters seem to be very generic and adaptable to any configuration. Others seems to just be connector adapters. I really need some help on this one! There is a huge lack of information here.

Generally
$250 - transmission and hydaulics
$175 - Transmission adapter
$200 - Bellhousing
$120 - Clutch and pressure plate
$60 - Flywheel
$15-$100 - Not really sure how this works out. Lots of things called VSS adapters...
? - 3rd gen T5 console seems to be quote hard to find. Maybe modify Auto?

This should put me right around 1k for a much newer WC T5 than a 3rd gen unit. This is well under the going price for swap kits and the prices I have seen for just a 3rd gen transmission outside of a kit are astronomical.

Given all this, are the specific reasons any of this wont work?

jmd

iTrader: (4)

The adapter plate plus driveshaft and torque arm shortening is penny wise and pound foolish when a muncie pattern G-force case is available.

An aftermarket GM V8 gearset from the GearBox, instead of wasting time with the miserable V6 ratios is what I would do, but I have only daily driven both types tens of thousands of miles and am not as smart as those super knowledgeable hot rod people in the lands you have graciously explored for us.

On the topic of gears, a 2.73 rear kind of sucks with a T5. You may want to source a nice used rear with more gear, depending on what you have.
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The VSS in the 4th gen trans. can be stepped down in speed to feed your stock VSS buffer box using a Dakota Digital box, or similar. No wiring changes needed there except maybe the plug.

Sometimes, it's not easy being Christopher Columbus, and finding those deals no one ever thought of or found before, but someone has to do it, and I nominate you.

BTW, patience is a virtue. Oh, and buying the wrong parts is a sunken cost, not a "deal" that should be bought. Hope you find the parts you need, in due time.

PS, keeping a digital list of ALL the costs and parts required can be eye opening. I have one in Excel for an engine swap that I have updated for a year. Fasteners, different bellhousings, all the little stuff. It adds up. Good luck.

bchapp

I don't think there will be a need to shorten the driveshaft or torque arm. I am assuming the additional length will be under 1/2" and the give in the torque arm bushing might give me what I need. Shouldn't have an issue with the DS. I am waiting on a call back from the adapter manufacturer on the exact length. I agree that if there is too much additional length to reuse or easily adapt, this whole thing is not worth it.

As to G-force or changing gears in the transmission, if money was no object, I wouldn't be putting effort into a T5 and would go with a T-56. I have a T-56 in my other camaro and would love to have one in this car. For this 92 RS, I am simply wanting something that I can row gears with, nothing more. I only have about $1500 overall in the car and putting in $2k+ worth of transmission isn't what I want to do right now. With the cheapness and availability of late model T5s, if I get the setup right, if one blows up I can just grab another one. There are about a dozen within 30 miles of me ranging from $125 to $300.

In a few months I will be getting a 4th gen rear with 3.23 from a friend who is currently building a 9 inch for his 1999 Z28. This will help out with the gearing.

As to your suggestion on documentation, I have an excel sheet of everything I want to do to the car, the supplier, PN, cost, etc... I am also keeping it up to date with my actual costs versus estimated for consumables, etc...

Drew

iTrader: (58)

Sounds kind of stupid, OP. Why not spend that $1000 on a thirdgen T5, or a T56, or hats with witty sayings printed on them. Just seems like you're jumping through a lot of flaming hoops to save a little on the transmission. You're opening yourself up to unforeseen pitfalls and a hacked together finished product when you could just work some overtime, recycle some scrap, or sexually satisfy elderly women, and just do it right the first time.

bchapp

Thanks for the witty insight, Drew.

$1800 (Hawks) for a 30 year old unknown mileage transmission swap is hard to swallow. $2800 (again, Hawks) for a T56 is pretty wild. $900 for a 15 year old transmission swap seems a little more palatable.

My suggestion here is simply to use a transmission adapter so I can use the newer T5. Seems that simple to me.

jmd

iTrader: (4)

NowhereFast

Don't go looking at Hawks, that's the first issue. They're prices on some things are ludicrous. You should be able to find a third gen T5 for under $800. Even if you have to travel, that's much less work than the endeavor you're about to incur.

Drew

iTrader: (58)

LOL Hawks. Hawks is for people who don't have time or the patience to use Craigslist. I live in a small town and have seen at least three LT1/T56 cars, complete running driving cars, recently for roughly $3,000 each. Considering those are asking prices... Seen a few different TBI T5 cars that would make decent parts cars too. Even a couple trans setups that were already out of the car. Now if you widen the spread of the ol' feelers, post want ads, follow the forums, Ebay, Facebook, Craigslist, local classifieds, etc you might just find what you're looking for.

People get these ideas to do things different. Like they had the light bulb come on, and came up with an idea that was so original it's never been considered before. And at least in the logical part of the idea, it almost makes sense. It seems plausible. But something just doesn't quite add up, so we jump on the internet and start digging deeper. The way it usually works out, is that if the idea has rarely been considered, attempted, or even accomplished, it's usually a good indicator that there are better ways to reach the desired end result. Most of the time, it's best to follow the road well traveled.

Galaxie500XL

iTrader: (1)

As someone that owns an '88 L98 with a V-6 T5 (previous owner swapped the auto), I might have some insight.

If your proposed T5 has the same 4.03 1st gear ratio, you're going to find out very quickly that even with a 2.73 rear gear, 1st is so short as to be nearly useless. I'm shifting into second gear at intersections even before I clear the red light.

Patience can be your friend...I spent nearly 3 years finding a decent T56 for $800.00, (Cragislist, of all places), and am in the process of gathering up all the parts to do a T56 swap into my '88. The transmission seems solid, but I'm rebuilding it anyway, because I don't like surprises.

That said, I'm currently driving the car now, but will be finding myself in the position of having an awful lot of T5 parts--bellhousing, clutch fork, flywheel, and even 3rd gen pedals (geometry is different between 4th gen and 3rd gen pedals, so I'm swapping to 4th gen pedals and hydraulics)...

I'd be tempted if I were you to find a 4th gen T5 V6--they're common as dirt in the yards, and get EVERYTHING. All you'd need at that point to do the T5 swap would be 3rd gen pedals, hydraulics, the flywheel, and V8 bellhousing.

It will be likely a couple of months before I actually do my T56 swap, because I'm currently having Pro-Force Performance in Georgia rebuild the T56 before I install it--but after it's installed, I may have everything you'll need, with the exception of the T5 itself--mine ingested a lot of water over the winter (torn shift lever boot), and 5th gear can't be engaged...and besides, mine uses a speedometer cable, rather than a VSS.

My car was already swapped, and while I was thrilled to have a manual L98 IROC, and having a manual has been a blast, the fragility of the T5 coupled with the poor 1st gear selection has left me dissatisfied--and over the past 3 years, having driven my '88 40,000 miles, I still feel the same way. The only reason I've put up with it this long was the difficulty in finding a decently priced T56.

bchapp

So far I have been digging in the local salvage yards and looking on craigslist. I haven't had luck finding any 5 speed 3rd gens at all. E-bay and Hawks seem outrageous, and the For Sale board here seems pretty dry for full transmissions. Hence looking at adapters for a 4th gen.

Drew, do you know of anyone using the G-force case? The spacer you showed won't be be necessary. I found out the adapter will interfere with hydraulic throwout so the only solution is to use a 3rd gen slave and throwout.

I also heard back from Hotrod Works. The adapter adds 0.550 to the total length. That probably kills this. I don't see any way to deal with that much added length without modifying the driveshaft.

Are there tricks to finding yards with 3rd gens? I find them by themselves in a neglected corner. Always lots of 4th gen V6 cars.

Galaxie500XL

iTrader: (1)

Had I known about this a month ago, there were three in a yard not far from me in Knoxville...two Camaros, and a Firebird.