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t4 plus Porsche 915 tranny in my 74 pcar. is it possible?
Posted: Tue Jan 23, 2007 2:16 am
by Brewtech
I'm getting a 915 transmission for my p-car and was wondering if a T4 can be mated to it?
Posted: Tue Jan 23, 2007 3:08 am
by Twystd1
It's a bolt on.....
Remember the clutch accuating mechanism is the opposite of a 914.
Push VS Pull
C
Posted: Tue Jan 23, 2007 6:35 am
by dr. no
What year tranny? That's what makes the difference.
Go here
http://www.shoptalkforums.com/search.php and at Germanlook.com, this has been covered.
Posted: Tue Jan 23, 2007 7:28 am
by Dave_Darling
The 915 uses a different style input shaft than the 901 (and 914) transmissions do. It will not bolt right up, not without some "adaptor" parts. I believe that Kennedy Engineering sells the correct flywheel and clutch to mate a 915 with a Type IV (or 914) engine.
--DD
Posted: Tue Jan 23, 2007 7:37 am
by MASSIVE TYPE IV
I offer a conversion flywheel that bolts the TIV directly to the 915 tranny and uses the 915 clutch, pressure plate and etc..
One of my customers uses this in a 912E Rally car, he removed the 923 and went 915 for better durability. I can get pics of the clutch cable mods if you want..
Posted: Tue Jan 23, 2007 10:32 pm
by Twystd1
My bad... Not a full explanation.
I gotta think before I write........ Thats another lesson to learn.....
The bolt pattern
for the transmission IS a direct bolt up to a TYPE IV.
I should of gone the distance and written up the whole setup.
Here is link
for a fella that had much the same question.
http://www.914world.com/bbs2/index.php? ... =66813&hl=
Let me go look and see if I can find you a pictorial view and a thread of this swap.
Maybe DD can find something from his archives.
Lets see what I can find...
Clayton
Posted: Wed Jan 24, 2007 2:45 am
by Twystd1
OK,
I posted up on a couple of boards to help find pics and a thread
for a how to swap a 901 to a
915. Assuming this is what you want to do. (let us know)
Lets see what the fellas send us tomorrow from the Narp, 914World and 914Club boards.
I know I have seen a thread that takes it from nuts to bolts all the way through the swap. Just can't find it. (Yet)
There is one setup with a Tilton Hydro TO bearing and another with the more familiar mechanical linkage. And still another with a Hydro Slave/Master setup
for clutch attenuation.
You may also want to look at what WEVO has if you are going balls out.
http://www.wevo.com/Products/WevoProducts.htm
Very nice products indeed......
Clayton
Posted: Wed Jan 24, 2007 11:26 am
by Twystd1
OK,
I B thinking you are talking about a 912.
I started at thread at another forum specific to your question.
There are many opinions that will offered up if you even need a
915 trans.
I thought it might be fun
for you to get some data from several fellas that have done this conversion on a 914.
There are pro's and con's to it.
You might want to check it out. Even though a lot of the data is specific to the 914. Some of the information carries over
for a 912 or early 911.. You might find it interesting either way. Good stuff.......
http://www.914world.com/bbs2/index.php?showtopic=67308
Regards,
Clayton
Posted: Thu Jan 25, 2007 4:19 am
by tomtom
I'm doing such a conversion in the moment. I'm using a
915/06 gearbox. The flywheel is a 228 bus and I use a Kennedy Stage 1 pressure plate. The tricky part here is the disk. We have a guy in Germany that builds bugs with subaru engines
for living and he is offering a 228 mm
cluch disk that fits into the pressure plate/flywheel and fits as well to the gearbox. This all with torsion springs. Just be aware what
915 you have there are two dimensions tooth profiles.
I'm using all parts of
www.bugat5speed.de . With this parts it is easy to implement the box to a beetle. I will post some pics while i'm installing the box. We are going hydraulic
for the
cluch relieve so we do not need to bother with the cable installation.
Posted: Fri Jan 26, 2007 12:27 am
by Wally
tomtom wrote: We are going hydraulic for the cluch relieve so we do not need to bother with the cable installation.
Hi Tom,
I am very interested what hydraulic slave cylinder you will be using and how its attached?
Also what starter motor do you use with the
915 trans and the Bus 228 flywheel? I noticed you need a much larger throw and no stock starter will reach that far...
Danke im voraus,
Walter
Posted: Fri Jan 26, 2007 3:37 am
by tomtom
Wally, the only starter capable ist the high torque ini-104. This is meant for the 091 vw bus tranny. You can try the original too (http://www.lichtmaschine_anlasser.autoteile-info.de/showpic09.php?ArtNr=103390&Einspeiser=90)
We tried a csc (concentric slave cylinder) to be installed but seem not to work since there is not much space left. Now we will use a 944 master/slave assembly. More when we succed.
Cheers, Tom
Posted: Fri Jan 26, 2007 3:53 am
by Wally
Thanks Tom,
I now use the Saco kit which I adapted a bit for the 915 use, but I find the stock 225mm 915 pressure plate still a bit too heavy, even with the hydraulics..
Did 'they' or you ever consider a hydraulic slave throw-out bearing? I have never found one, but IMHO, it would be the way to go.
Advantage with the stock 915 pressureplate is you can just use a stock 914/915/VWautomatic starter. The only custom item now is the special Kennedy 915 flywheel that bolts to a type 4 crank.
Like you said, clutch plates that fit a 228mm flywheel and have the posche splines need to be custom made unfortunately. The original 225 porsche 915 clutchplates don't fit VW 228mm flywheels...otherwise it would have been easy..
What did you pay for the kennedy Stage 1 custom plate if I may ask?
Tnx,
Walter
Posted: Fri Jan 26, 2007 5:26 am
by Twystd1
WEVO hydro T/O bearing and racing clutch assemble.
http://www.wevo.com/Products/ClutchProd ... erlite.htm
(scroll down to bottom of page
for the hydro bearing pic)
Rich Johnson sells a kit from Wes Hildreth that is a master / slave setup
for about 1200.00 bucks. Uses some 928 parts.
Interesting conversion
for a hydro master / slave on a 901 in a 914.
This is a good DIY thread.
http://www.914world.com/bbs2/index.php? ... Ca%20href=
And.... A couple of guys have done it
for a couple of hundred bucks as a DIY setup
for 915s in a 914.... And that is basically the same setup as a 912/911.
I have more pics if needed.
Hope that helps.
C
Posted: Fri Jan 26, 2007 6:30 am
by Wally
Thanks Clayton!
I had seen that page before but had all forgotten about it to be honest.
I WILL try to persuade WEVO to sell me the annular hydraulic trow-out bearing thingy seperate
It would be awesome if that would succeed. Its _exactly_ what I want to make a clean
915-type 4 install with as much stock parts as possible.
Wevo does make the nicest things. Already got their tranny mounts (through Pelican)..
The main benefit I see here is that you can skip the whole pivot arm of the throw-out release system. That has got to make a noticeble difference in drag and hence a lighter actuation of the pressure plate.
Now lets hope that annular hydro bearing has the same radius at the contact point to their high-tech pressure plate as the stock
915 pressure plate does, where the bearing is normally attached to the pp...
If not, I can always use/adapt this
for the VW 228 pp
Thanks again,
Walter
Posted: Fri Jan 26, 2007 12:06 pm
by raygreenwood
Annular hydraulic cylinders are very common in GM productsand many Jeeps. The Saab 900 series had a very nice thin one. They do have a couple drawbacks though. (1) If it fails...the tranny comes out. (2) They have a shorter lifespan than normal slaves mostly due to the dust. I had to replace the one on my Saab about every 15+ months....although that one was easy to get out. (3) Most have a short throw unless you find ones like used in Jeeps...that have a deeper cylinder.....then it becomes a space issue.