Alfa Romeo Forums banner

1 - 20 of 96 Posts

·
Registered
Joined
·
115 Posts
Discussion Starter #1
I'll start this thread by saying that the reason for this swap was purely to improve shift quality which is only a problem due to my inability to double clutch. Definately more of a driver issue than a trans issue. There...now that we have that out of the way. The other reason I'm starting this thread is to put together a comprehensive list of information (pictures, drawing, models etc) that can help others put this swap together with relative ease. I haven't completed the swap yet but I do have the T5 built and the adapter to the bell housing made.
I wanted to get the information out as I worked on it so it was still fresh in my mind.
After taking a hard look at the T5 bearing retainer (the front part of the trans that the throw out bearing slides on) I decided the best course of action was to trim the retainer down to accept the stock Alfa centering ring in order to locate the trans to the bell housing. This kept the axial location between the trans and bell housing just between the two parts and did not involve the adapter plate. More importantly it meant that the bolt patterns and clearance hole for the bearing retainer did not have to be high tolerance thus keeping the cost down and the risk of radial misalignment minimal. See pic below;
 

Attachments

·
Registered
Joined
·
115 Posts
Discussion Starter #2
I took a 3D scan of the T5 bearing retainer to ensure there was enough material available once I machined it to the required dimensions to fit the centering ring. My trans builder (Rick at T5 Specialties) had some concerns in this area so the scanned confirmed it would not be an issue. See cross section taken vertically through the two oil feeds;
 

Attachments

·
Super Moderator
Joined
·
10,635 Posts
I'll start this thread by saying that the reason for this swap was purely to improve shift quality which is only a problem due to my inability to double clutch. Definately more of a driver issue than a trans issue.
You don't need to justify this project, at least not to me. It just seems like a cool thing to do, which is reason enough for doing it.

I do have the T5 built..
By "built", I assume you mean that the appropriate gears were installed. What ratios did you chose, and how were they selected?

I will be curious to see how you handle the driveshaft conversion.
 

·
Registered
Joined
·
115 Posts
Discussion Starter #5
I'll post the parasolid of the adapter along with some drawings of the retainer modifications and the adapter a bit later. Here is the adapter mounted on the bell housing, the bell housing mounted to the trans and T5 input shaft showing through the Alfa bell housing with the clutch fork and throw out bearing in place;
 

Attachments

·
Registered
Joined
·
115 Posts
Discussion Starter #6
AlfaJay...you're getting ahead of me.
The trans body and output shaft is from a 95 Chevy Sonoma. The 1-4 gears are from a 95+ Mustang with the first gear being from the Sonoma (on the output shaft). the reason Rick stayed with the Chevy out put shaft was two-fold. First, he builds a lot of transmissions for Ford guys so having the spare Ford output shaft was a bonus, second the yokes are cheaper for the Chevs than the Fords. I haven't looked too far into this but on the surface it seems to be true. In all honesty it doesn't really bother me one way or another.
The drivesahft will end up being customer from scratch. I'm heading to London Driveshaft tomorrow to get the talks started and see where I need to go with adapters and what not. plan A is to have a driveshaft made with common u-joints front and back mated to a Chevy yoke and a flange style yoke at the back. From there I'll make an adapter to mate the driveshaft rear yoke to the differential flange. Should be a simple adapter using the centering features on the yoke and the diff flanges.
If I manage to get my butt off the couch and get out to the garage I'll get the trans mounted so I can start looking at the cross member.
For a mount I was going to fab something up but after a quick Rockauto search I found a mount (ANCHOR Part # 2672) for a 95 Sonoma for $4.14. Not worthwhile fabbing something for that price.
 

·
Registered
Joined
·
115 Posts
Discussion Starter #7 (Edited)
The 3.8l Mustang gears are: 1st 3.35:1, 2nd 1.93:1, 3rd 1.29:1, 4th 1.00:1, and 5th 0.73:1. These line up pretty well with the Alfa gears which I'm pretty happy with. The input shaft is 7.85" long which makes it perfect for a 5/8" adapter plate. The input shaft pilot bearing diameter is 0.668" so I'll likely use an Alfa pilot bearing that's been bored out to fit the input shaft.
I've ordered a clutch kit for a 78 2.3l Mustang 2 which has an 8-1/2" disc (SACHS Part # K031504). I ordered the kit because I couldn't locate just the disc. The bonus being that it also comes with a centering tool which will save me from making one. I'll take the wins when I can.
 

·
Registered
Joined
·
115 Posts
Discussion Starter #8
I went with the Pro 5.0 shifter because it was getting good reviews, was recommended by Rick at T5 Specialties and had a simple two bolt pattern that I can fab a new shift rod to. The action and quality of this shifter feels great. I'm really looking forward to running it this spring.
I looked pretty extensively for one for an S10 with no luck...it turns out Camaro one is a direct fit except that the rod is cut on an angle to allow for the rotated orientation of the T5 in the Camaro. This of course is not a concern since it'll be coming off for a new one that will suit the Alfa.
The Pro 5.0 shift is for a 1983-1992 Camaro / Firebird and the P/N is 813-P3050 on the Jegs site. I picked mine up on eBay.
 

Attachments

·
Premium Member
Joined
·
2,790 Posts
I use Pro 5.0 shifters on my T5 equipped Mustangs. Its a great shifter.

Its important to know which T5 is being used. There are several varieties, including World Class, non World class, input shaft lengths and diameters, etc. Thanks for detailing which transmission, and the specifications. Its not a "one size fits all" conversion.

Bob
 

·
Registered
Joined
·
115 Posts
Discussion Starter #11
thank you.. I have been making these for 3 years now..not going to make them anymore. I spent a lot of time and $$$$$ doing this, thank you again
Hey Bianchi,
I sent you two emails requesting info on your adapter kit. One on 2 Sept 2014 and one on the 28th of October. No response from you so I didn't think you were making them anymore. I'd much prefer ordering something over engineering a solution. All things considered the information available on the web combined with the availability of a 3D scanner and some decent Solidworks skills made this a fairly straight forward plate to make. The tricky parts for me were figuring out where to and the amount to machine the T5 bearing retainer down to fit to the centering ring on the Alfa BH. That was about an hour of staring at it and trying to figure the best way to do it. The rest was just bolt patterns. Again...some simple web help and a scan of the Alfa BH and it was done. Whole thing took about two hours once the concept was solid. Sent the model over to the local machine shop and in a couple days I had my plate. Popped over to see Rick at T5 Specialties and put the whole thing together. As my son would say..."Easy Peasy".
I'm pretty sure most people won't want to build something if they can order it. I would recommend responding to emails when potential customers are interested in what you have to offer otherwise they'll be interested in making their own.
 

·
Registered
Joined
·
115 Posts
Discussion Starter #12
I use Pro 5.0 shifters on my T5 equipped Mustangs. Its a great shifter.

Its important to know which T5 is being used. There are several varieties, including World Class, non World class, input shaft lengths and diameters, etc. Thanks for detailing which transmission, and the specifications. Its not a "one size fits all" conversion.

Bob
Hey Bob,
I did a ton of reading on the transmissions. I sent an email to a fellow on the web that was advertising rebuilding T5 transmissions to spec out what I was trying to do. It turned out he's a bit of a T5 nut with a wealth of information. I think initially he thought I was a little batty for what I was looking to do but as our conversations went on we managed to get synced up and got the trans built.
A good chunk of my frustration with doing this was the vague info out there. Like you said...not all T5s are the same.
I'm trying to make sure I'm specific as possible on this post so others can do the swap if they want. If I miss anything let me know and I'll try to answer.
 

·
Registered
Joined
·
115 Posts
Discussion Starter #13
I spent a little time this afternoon doing some tes fits of the trans in the tunnel. In a nutshell...it didn't fit. Close but no cigar. The first three pics are some shots showing how close the shifter location is between the alfa trans and the T5. There are a couple pics like this bouncing around so nothing really new here. My adapter is 5/8" thick and a couple other guys are going 3/4" which I don't see any real issues with. I went 5/8 to keep the input shaft at the same position as the current Alfa one. Another 1/8" back shouldn't matter much at all. It's a little tricky to measure but the T5 shifter is sitting about 1/2" further forward than the Alfa shifter. I don't have any concerns at this point.
 

Attachments

·
Registered
Joined
·
115 Posts
Discussion Starter #14
Now for the "it don't fit" pics. There are a bunch of little tabs that presumably are for wiring harnesses, machining datum etc. which are hitting the tunnel. The reverse switch looks like it may be an issue too.
Here are some pictures of the tabs hitting the tunnel. The ones on the left show the reverse switch.
 

Attachments

·
Registered
Joined
·
115 Posts
Discussion Starter #15
Now for the T5 diet/slimming pics. A mini grinder, a cut-off wheel and an angle die grinder to make things pretty made quick work of the tab removal. These things all sit outboard of the main casing so I don't foresee any issues structurally.
 

Attachments

·
Registered
Joined
·
115 Posts
Discussion Starter #16
Removing the tabs made all the difference in the world. I skipped one on the top cover on the drivers side thinking that it wouldn't be in the way but I forgot the tunnel curves. I'll have to touch that up.
I managed to get the transmission bolted up but it's touching the tunnel on the aforementioned tab on the left and on a rib in the floor on the right. It looks like a little massage on the floor board will help the reverse switch issue and I noticed there's a couple bosses on the back of the tail stock that are lining right up with some structure in the tunnel and are too close for comfort. So some additional mass reduction will ensue along with some minor modifications to the floor with a dead blow hammer.
The cross member mounting position lines up pretty good with where the trans mount so the cross member should be fairly straight forward. That'll have to wait until I get the diff back in so I can get the angles right.
 

Attachments

·
Registered
Joined
·
115 Posts
Discussion Starter #17
Here are a couple of the drawings for the bolt pattern and the T5 bearing retainer modifications. The holes are sized for M10 SHCS to attach the plate to the bell housing first then M12 bolts to attach the plate and bell housing to the T5. I'll suggest using nothing less than 8.8 grade fasteners. I'll post the models next so you can either give it to a machine shop or have someone water jet the profile and holes then counter bore as needed.

View attachment T5 Bearing Retainer Machined.PDF

View attachment T5 to Alfa Bell Adapter Plate.PDF
 

·
Registered
Joined
·
57 Posts
Wow! This is just what I was looking for. I know Bianchi has a kit, but I like to have the fun of building things myself.

I just spent the whole day working on cleaning out my shop, so I can get this project on the timeline. I'm finishing a short-course race truck right now, and have to build a utility trailer as well, so I need to finish those two before the alfa project begins.

So for now, I was just going to collect parts and see if I could find a CAD dwg of a T5 to make a drawing for an adapter plate.

I'm prepared for a little "fitting" to make the trans fit the tunnel, I'm keen to see how you make out.

Thanks a million for posting the files! Good luck on your project!
 

·
Registered
Joined
·
115 Posts
Discussion Starter #20
Hey Chill...I'm pretty eager for the weather to turn around so I can take her for a run. At this time i don't foresee any issues.
What's your plan for the speedo? i have a GPS speedo so it's a non-issue for me.
 
1 - 20 of 96 Posts
Top