[Super newb] Does anyone mind answering some of my questions about viable transmissions for my V8?
Hi everyone, I will fully admit I am a novice at this stuff and know very little but am trying my best to complete a V8 swap with some friends who are very knowledgeable and skilled (at welding etc). The issue is they don't have much knowledge about V8s and old transmissions and neither do I.
I have a L33 Aluminum 5.3 Vortec V8 that I am swapping into my 1985 RX7 FB. I know the easiest solution is to use a T56 trans most likely from a 4th gen Camaro. Very few of those in my area so I am looking at the T5 World Class transmission.
From what I've read I am supposed to look for a T5 with 26 splines. I don't know necessarily why though, it has to do with the clutch.
There is a T5 world class in my area that I can afford but it is 10 spline. Is there any way I can get a clutch that would work with my L33 engine and fit the 10 spline? Can you remove the 10 spline from the T5 and change it for a 26 spline?
I wish there was a general thread I could ask dumb questions instead of making a new thread but doesn't seem so...
Any help would be appreciated thank you.
EDIT Forgot to mention I am only looking for manual transmissions not going auto.
Posted Jun 18, 2023, 4:45 PM UTC · edited
So you are aware, there are World Class and non World class versions of the T5, as well as several different shifter positions and quite a few different gear ratio combinations.
The 26 spline input shaft transmissions are used in GM vehicles, therefore will mate to a GM/Chevy pattern bellhousing correctly, and have the correct pilot size and depth. As far as I can remember, the only T5's with a 10 spline input shaft were in Ford applications. This will not mate with a typical Chevy bell housing easily.
In my view, the v8 transmissions with the 2.95 first gear ratio are the nicest, they are World Class (which has nicer bearings, synchros, and shifter improvements) and the gear ratios are about ideal for a small block v8 with a nice street powerband. The tricky part for you, this trans in Camaro and Firebird applications had a 22 degree tilt of the main case, which is a bit funky to adapt to other vehicles. The v6 Camaro and Firebird trans did not have this, but those have less desirable ratios.
It is possible to get a bellhousing that would adapt the Ford t5 to a Chevy v8. I have not done this personally, but I have seen the parts. I don't know if this will require a change of the input shaft and throw out bearing sleeve.
Then there are shifters in different positions, different speedometer gear configurations, and different output shaft splines. I know it seems overwhelming, but a bit of research and resourcefulness will get you a combination of T5 parts that will work perfectly in your swap and will only be exceeded by a $3000+ aftermarket transmission. It is workable.
Some will say a T5 is weak. They are definitely not the strongest of transmissions. But driven sensibly they do work well behind engines like your 5.3.
Thank you for this information it is very helpful. Yeah lotta Mustang guys around my neck of the woods so many of the T5's I find are 10-spline Fords. A guy with a non-WC T5 26 spline I talked to told me the one he had would not work well for my engine due to the ratios like you were talking about even though it would mate. He told me about an adapter plate (expensive but it works) by hotrodworks.com but I am trying to avoid having to use that.
The engine I have I think is rated for about 315 HP stock and I don't plan on beefing it up more than that really as the RX7 is already very light. I am not planning to make my car a drag car or racer nothing like that just wanna cruise.
I was worried about the 22 degree tilt. I watched a lot of the videos by driftingdad who used a T5 with a LM7 and he got it to fit into the car perfectly but can't remember now maybe it involved bending the shifter or he welded a new shifter that was offset by 22 deg or something like that.
Right now I gotta find a trans I can use before worrying too much about that.
There are other transmissions, but for fit and ratios the v8 T5 is probably best. A QuickTime bellhousing to mount a Ford trans to a Chevy v8 might be an option for you.
Hmmm never heard of QuickTime bellhousing will look into that. I think for a GM T5 I need a 621 GM bell.
The 621 casting bellhousing has been around forever. It takes transes with the 4 ears like many traditional GM units, including some T5s. They usually have the smaller bearing retainer bore, some may have had the larger bore. They have been reproduced, but some are poor quality. You need to mount a dial indicator to the back of the crankshaft with just the bellhousing in place and indicate that bore. I have had a few come through that were off more than .030 inch. You can buy offset dowels to help dial that in, but some are so bad you don't want to start with those.
Do you know if a 1994 4th gen Camaro T56 will work with my 2008 5.3 L33? I think I found one I could buy but it is expensive and a quick search is talking about there being an LT1 T56 and an LS1 T56 and it seems the LS1 came out in 1998 so I'm guessing this is an LT1.
The info was saying that I'd have to get a whole conversion kit for it to work and it's almost a grand US just for that....
Very frustrating :/
I don't know all of the differences between the two versions, but it's significant. You will spend quite a bit getting the early trans to work like the later trans.
Before you get too far with the T56, will it fit in your car? The T56 is a poor fit in many vehicles, often requiring floor modifications. Or, you end up with funky driveline angles. On some cars it's nearly impossible to resolve all the fit issues. And then there is shifter position. Combine those issues with what are, in my opinion, gear ratios intended for emissions and CAFE compliance, I don't see a T56 being a good choice. They certainly get a lot of hype, but I am not interested in hype.
If you are going to sink $3k plus into a trans, look at buying the newer TKX. It's far stronger than you will ever need, it fits well in many vehicles, has numerous shifter positions, and has excellent gear ratios. Downside, they are not cheap.
Yeah it seems it really needs to be a 1998+ LS1 T56 to work. All I know is the two transmissions that fit the FB with a 5.3 is the T5 and the T56. Almost all the V8 swaps for FBs use those two choices. And guys who used a LT1 V8 I suppose can use the pre 98 T56s.
The only mod needed I think is if you get the transmission that is at that odd angle you might need to use a curved shifter instead of a straight one to avoid cutting up the shifter tunnel (pretty sure that's what DriftingDad had to do with his build on youtube).
Remember I am in Canada so a 3k trans+ shipping from the states is more like a 4.5K transmission for me.
The search continues...thank you for your comments I appreciate the help.
I think you are going to find the T56 is actually not an easy fit. People will live with them hitting the floor, sitting at odd angles, tearing up the mounts and u joints. They get odd driveline vibrations sometimes, but they can somehow ignore that. In my view, none of that is acceptable. You might feel differently.
I know your Canuck Peso exchange rate isn't doing you any favors. Be patient. Maybe you can find a trans from a v8 F body, and change the tail housing to suit your swap.