Strife1126

So I have a 97 firebird with the 3.8 and a t5, and I'm trying to swap in a lq4 with my t5 behind it. I would go T-56 because it's the much better option, and when I get the money I will, but for now I'm just trying to make the t-5 work. From what I understand, I need a "621" bellhousing, ls1 clutch and flywheel and a mustang t5 tail housing. I already have a t5 out of a foxbody that I have sitting on the shelf that I'm not going to use. So would all I need to get is the bellhousing? Also I'm pretty sure it's a internal hydraulic throw out but I'm not 100% sure.

dannyual777

Strife, I had to read your post a couple of times to understand what you're trying to do and what you're asking. I'm still a bit confused. You mention your '97 Firebird with the 3.8 and a T5 but then you mention a Foxbody T5 transmission that "I'm not going to use." I'm sorry I can't help you with your bellhousing question but I can tell you that my 1991 Foxbody T5 had a cable actuated throw out bearing. I'd guess that your Firebird T5 uses a hydraulic slave cylinder.

garys 68

iTrader: (1)

Look up the T5 v6 input shaft specs vs the GM V8 input shaft. It's not worth the effort. Add to that, it's very weak. Adapting the stronger Ford T5 might be easier. Add to that the trans bell pattern wont work easily.

Strife1126

I did some reading and I believe it will work out, I found a 621 bell for the t5 for pretty cheap and I already have the tailshaft housing from the mustang t5 to compensate for the angle it will be mounted at. All I really need is a clutch kit that will fit the lq4. I already have the different splined input shaft and brand new bearings so if I really need to I can just swap the input shafts.
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garys 68

iTrader: (1)

Going by memory here (over 10 years ago), but I think:
The 621 has the GM muncie/T10 bell/trans bolt pattern
The V8 camaro T5 is15 degree canted with the 621 bell/trans pattern and a GM 26 spline input shaft
The V6 T5 has a different input shaft and different bell/trans bolt pattern (It may be the same as a ford)
The Ford T5 has the standard Ford bolt patter and input shaft. I've seen conversions using a 1/2" adapter between the bell and trans and an adapter pilot bearing to bolt to a SBC. They also used GM pressure plate with ford disk.

Strife1126

Interesting, thanks for the info. I kinda jumped the gun and got the 621 bell on a good deal but you're right on the input shaft and mounting pattern. 3 of the bolts will line up if I slot the holes on the t5 but the bottom right bolt hole is wayyyyy off and there's not enough meat on the bellhousing for me to drill and tap another hole. So i'm going to have to figure that out. I feel like i'm kinda on my own here because I haven't found a lot of info out there on the v6 to v8 stuff. And on top of that its a 6.0 lq4 which most people do the 5.3 or the lt1 that came in the v8 cars.

Y2K_Frenzy

Not exactly helpful but it’s a decent read on T5’s. The many different faces of the T5

garys 68

iTrader: (1)

You said you have a mustang V8 T5. Go over to corvetteforum C3 page. Several have used a 621 bell, 1/2" adapter and the ford T5 with an adapter pilot. That with the sachs 1050 flywheel, BBC PP, ford disk might work.

jmd

iTrader: (4)

Jumping all over here, the Ford T5 can't accept a GM 26 spline input. The gear tooth count is different unless you have a 93 Cobra or Motorsports 2.95 box, which should be old to fund a Magnum. Moving on,

Mock up the 1050 flywheel, the clutch you want to use, the 621, the adapter for T5 to 621, and slave cylinder.

You need pilot tip to bushing/bearing length matchup, spline to disc engagement, slave to pressure plate gap, concentric run-out and if that is all good, proceed.

The Ford tail will need the upper shift rail, reluctor ring moved and an inline VSS boss placed if your Ford T5 was speedo drive (most are.)

You'll be into it (however deep the time, parts, and fab cost) and have miserable wide V6 ratios. Nothing will drive or perform better though, which is usually the water test to justify a custom swap. Practice mocking stuff up.

You may find the decision clearer if you tally up the actual full costs to "save and use" a T5. Using as simple of parts as possible (2002 Camaro clutch, flywheel, and hydros with a Magnum) can save headaches and serviceability.