Type 1 weak spots

[Brett Proctor]

I'm leaning towards putting a subaru engine with a type 1 transmission in the car.

What are the weak spots in the transmission that need to be rebuilt or replaced with after market parts to hold up to the HP of the subaru? The stock transmission will probably hold up to the way I drive but I want to make it as bullet proof as possible. Once its all together I don't want any problems with it. Its alot easier to fix it now than it will be when its all together.
I've seen rhino cases, super diff, diff covers, plus what mounts does everyone prefer. The polyuathane or the good old stock rubber ones? I was thinking the rubber ones would be better(would absorb the vibration better)

Thanks
Brett

 

[letterman7]

Good question, Brett. The guys who still run VW transaxles in their sandrails with Suby power seem to almost universally have a super diff, gussetted side plates and welded 3/4 syncros inside. Depending on whether your transaxle is a swingaxle or IRS will determine how you actually get the power to the wheels. With an IRS many guys go with the Porsche 930 flanges and heavier drive axles. A swingaxle offers slightly higher horsepower ratings stock, and there are heavier duty race driveshafts out there as well. Rubber mounts are usually best, they'll transmit less vibration through the car. A transaxle strap is a requirement, both front and rear. But the weakest link is the first gear gear and syncro. I've heard some people say to just start out in second, others prefer to swap the gears anyway for different ratios and strength (usually out of a Bus). Check on other VW oriented forums for the different combinations folks are running.

 

[Brett Proctor]

Sorry I missed that bit of info. I have a IRS transmission.
CV's were another thing I was wondering about along with what clutch to use.

Thanks
Brett

 

[letterman7]

You should be fine with the stock CV's, unless you're planning big horsepower. The adapter kit from Kennedy typically comes with the 1700# clutch pack, I think, but check their website to be sure.

 

[Brett Proctor]

I thought I would update this post with what I found out while rebuilding my type 1 transaxle.

I've read stuff about people saying that a type 1 transaxle will or wont handle the power of an engine swap and maybe thats because of the year of the transaxle they have.

The IRS transaxle from what I found out went through numerous up grades but there was 3 major upgrades (I think) that were made that makes each generation stand out above the previous.

The first generation of IRS transaxles were just a conversion from swing to IRS. The insides were pretty much the same and this to me was the weakest IRS transaxle.

The second generation was between the years of 1970 to 1972 1/2. The pinion shaft was changed for a splined 4th gear(old style used a wood ruff key) it also got a new style pinion bearing , new syncros, and new style 3rd and 4th gears, different style of throw out bearing, larger and stronger fork for throw out bearing and I think it got the 200mm clutch.

Third generation 1973 and later got a few more upgrades to the transmission but the main change was the case. It got a hole new case design. They went from a dual side plate configuration to a single side plate. So its real easy to spot one of these. If it has just one removable side plate its the newer version.

Hopes this helps when your looking for a transaxle

If I missed something or if I'm wrong about something feel free to correct me. I'm not a VW guru in any sense

One thing more. If you decide to get into one of these you will need two VW specialty tools
The first is the socket to remove the new style pinion nut. It requires around 145 ft/lb to install and the input shaft is in the way. so this tool will let you torque it to the right specs and clear the input shaft. I found that long enterprise will rent this to you for around $30.

The other tool is the jig to set the shifting forks with. I had this done at a local shop here in town for $20

Brett

 

[groundflyer]

Just a note:The bus transaxle is stronger then the bug,

 

[Brett Proctor]

I tried to find a type 2 transaxle but living in the desert makes those a highly desirable item here for the off road guys. I can find two IRS type 1 transaxle for $100 on the local craigs list right now but no signs of a type 2. So I made due with what I had.

Brett