Hi peeps!

I know some are running boxter trannys..
My question is what year or model are best for the price and reliability?.

Thanks

For what motor? Won't work on a T4 without major modifications...

The Boxster 5 speed is virtually the same as the VW Passat. The Boxster tranny goes for $1000+ and the Passat goes for $400+. Some even cheaper.

The 6 speed comes in two variants (for the most part). One has a round bellhousing and one more triangular like the 944.

Audi make most of these trannies except for some 6 speed. My 6 speed is made by GETRAG.

My 6 speed is from a 2002 S model I think. It's a direct bolt on to my Audi motor. Both my 5 & 6 speed have about the same overall ratio and I do 80mph @ 3200 rpm. The 6 speed gear spacing is perfect for my turbo. I can speed shift it and never drop boost pressure.

Thanks Mike.

The motor would be a 3.6.
Since the boxter tranny is readily available compaired to 915 and others i figured i would ask the question.
Your answer was helpful thanks.

Good info Mike,
I know you and I talked about this before,
What shift linkage do you use ?
Since my car has an adapter 901 to SBC would the Passat need a different adapter? Not sure what bolt pattern on the Passat/Boxer transaxle.

I have a g87-21 that I am building an adapter plate to hook it to my 964 motor.

You can see pictures of the 3D printed test parts here.

That is my build thread.

Hooking an Boxster trans to an air cooled Porsche motor is no easy task. There are no compatible bolt holes to hook the Boxster trans and the motor, the Boxster uses a push type clutch and every 911 motor from 1971 on uses a pull type clutch, and the big one is there is no place to mount a starter.

All of these can be overcome. Once I do mine, I will be offering kits for sale, but I have to work out the issues with mine first.

For a T4 or /6 you would need to make an adapter for both the engine and the starter.
The route I'd look into is getting a VW bus auto trans bell housing, then machining off the Boxster bell housing to accept the VW unit.

I actually looked into that. It would require a LOT of cost in finding someone who can weld the new bell housing on the trans. And you have to be absolutely sure it is square to the input shaft. Otherwise you will have clutch issues.

Mine will be mostly bolt on, other than cutting the bell housing for the starter adapter.

different Mike here

Boxster/Cayman shifter and cables can be used.

You would need a different or new adapter plate and flywheel for your SBC for the Passat or Boxster transmission. Have you considered going LS-based motor instead of the SBC? Might be easier to sell it as a package deal.

Thanks other Mike,
Ya I have thought of LS, Subie, and -6 but if it ant broke don’t fix it. Just thinking one day that poor old 901 is gonna blow. The Boxter trans looks like too much fab work to adapt. Anyone ever fit the whole Boxter engine and trans in a 914, I remember hearing issues of being too wide between rear of the engine compartment, hits the trailing arms ???

My 6 speed is all Boxster stuff and my 5 speed passat uses a home made linkage, modeled after the Boxster with factory Porsche cables and shifter.

There was one cast boss on my tranny not drilled and tapped for the factory linkage. I did not feel comfortable drilling a hole in a perfectly good tranny. So I made my own linkage.

Took these pictures this past weekend. Yes, Boxster engine and transmission.
Click to view attachment
Click to view attachment

Look how much f'n room there is in there!

Something doesnt add up.. how in line is the axles with the flanges on the trans?

There was a member from Australia that put a boxster motor in a 914 and he had clearance issues to the suspension ears. I believe he had to remove the coil on plug and use a wire to a coil so it could fit but maybe he did not move the assembly forward?

Perfectly lined up when viewed from the top of the axles. In these pictures the motor/transmission assembly is about 3.5" off the ground. (sitting on a 4x4) so it needs to be raised up some.

The car is at stock ride height with 996 spare tires, ~24.8" diameter

Click to view attachment

What was not adding up was the fact that you are not keeping the stock rear suspension. So the answer to the question "can you install a boxster engine and trans in a stock 914" is still no

Andrew believes yes if you ditch the coil-on-plug and maybe modify the valve covers?