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Posted by: LotusJoe Oct 26 2010, 03:46 PM

Has anyone used type one CV joints? They are dimensionally the same. The type one joint does not use the gasket like the original joint. Also all the holes are the same size and will not accommodate the 10 mm roll pin.



I made some pins that fit the stub axle and transmission flange while fitting the hole in the type 1 CV joint. That way no modification is required to either component.


I used 1211 sealant in place of the gasket.



Anyone else done this?

Posted by: kg6dxn Oct 26 2010, 04:42 PM

I run 930 CV's but only because I was tired of breaking stock ones... Wonder what will break now???

Posted by: Cap'n Krusty Oct 26 2010, 04:48 PM

Eric Shea makes/sells 914 modded T1 CV joints. (PMB Performance).

Posted by: Racer Chris Oct 26 2010, 05:03 PM

Eric's CVs aren't modified to accomodate the stock gasket. Ours are!

Posted by: Elliot Cannon Oct 26 2010, 07:31 PM

Are these CV's better? Stronger? Cheaper? What, if any is the advantage?
Cheers, Elliot

Posted by: Vacca Rabite Oct 26 2010, 08:02 PM

You can still find them.
914 CVs are very hard to find.

Zach

Posted by: Rotary'14 Oct 26 2010, 09:59 PM

Hi Joe,, I like your simple fix.
Are your roll pins aluminum? because they look like it in the pic. If you make them out of steel, you should offer those for sale. I know I want 2 sets.

-Robert

Posted by: john rogers Oct 26 2010, 10:03 PM

I used Eric's CV joints on my vintage race car and the right side would generally last about 2 years and then the inner CV joint would fail. I ran a GT limited slip and generally the right side is still the heaviest loaded side. I ran 4 bolt Centerline wheels since they were about the lightest made and figured that the CV joints would last well but be the weak link as that is easy to change and better than a R&P or other trans problem you might get. I would make up a spare axle when I broke one so there was always an extra one with the trailer.

Eric's pins are steel as they take the rotational load and the bolts clamping force will not prevent the two halves from moving as the tightening torque is not very high. I would suggest you use steel or commercial roll pins.

Posted by: charliew Oct 26 2010, 10:07 PM

Those pins look like steel to me. I'm sure they aren't aluminum.

Posted by: Rotary'14 Oct 26 2010, 10:08 PM

Type 1 CVs are really easy to find and can be found for low cost. The only draw back is their maximum working angle is only 17 degrees compared to 22 degrees in our original 914 CV. This is due to the smaller balls and cage in the T1 CV. Empi (yeah I know they don't have the best reputation) makes an "off road race Type 2 CV" that has a working angle of 25 degrees and has a chromoly ball cage and bigger balls, they take more torque. You know bigger balls is better. I've read good things about the empi race CV on some other forums when I was doing some research. And T2 CVs will interchange with T1 CVs. Some good info below,,
http://www.blindchickenracing.com/How_to/CVJoints_Axles/cv_joints_101.htm

-Robert

Posted by: Eric_Shea Oct 26 2010, 11:24 PM

They are now...

Posted by: LotusJoe Oct 27 2010, 06:46 PM

Robert,
These are made from stainless stock I had lying around the shop.

Posted by: LotusJoe Oct 27 2010, 07:08 PM

Robert, I'm a bit confused. I just read the "CV Joints 101". The new type 1 CVs I got are dimensionally the same size as the original ones that came on my 914 (32.14 X 94). The only difference is the step on the out board side of the joint. If I read this correctly, the type 4 are 6mm bigger. Now I'm wondering if my old stock CV joints were something other than type 4. Although the article does not reference the 914, I'm assuming that the 914 uses type 4.

Posted by: Eric_Shea Oct 27 2010, 08:35 PM

No... I do believe Robert is wrong. McMark has some pictures around here somewhere that show the exact measurments and they are... the same (with the exception of the step you noted).

I've measured them as well. The 914 CV is identical.

I will tell you this, get GNK/Loebro CV's "ONLY". There are less expensive Meyle T1 CV joints on the market and their cage is not identical. It allows the CV to hyper-extend. If you are turning when your CV hyper-extends you will split this cage (turning out of an agressive parking lot apron while accelerating on to the road... very common).

Final note: I would not use the stainless steel pins. While they are a great idea, I think they might be more brittle (sigma phase embrittlement depending on the type used). I'd bet the factory steel roll pins are much stronger. I'd recommend buying the right bit and bore out the T1 hole to use the factory roll pin.

Posted by: plays with cars Oct 27 2010, 11:11 PM

Great information. Always good to find alternate components that are still available to keep our teeners running. Does anyone know how original -6 CVs factor in? Are they different than -4 and in what way? Any sage advice on alternate replacements for them?

Posted by: Rotary'14 Oct 27 2010, 11:17 PM

Even though our engines are type 4,, I NEVER said that those were the CVs we had in our car.(I assumed the maximum angle of a 914 CV is like that of a T4) 914 CVs are dimensionally the same as the T1 mentioned in the 101 site. 914 CVs are some bastard creation that are NLA. I mentioned that the T2 CVs were considered a "drop in" upgrade to the T1 CVs which the good folks here have been modifying to work for us. Just have to check the spacing of the T2 CV mounting holes to make sure they are the same as T1.
As far as "sigma phase embrittlement" concerns, don't use SS for the pins,, the harder the metal the easier it is to snap.



http://www.jimscustomvw.com/emofty2cjowc.html

-Robert


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Posted by: john rogers Oct 27 2010, 11:36 PM

I thought this had been beat completely before but I guess not. If you do a search on the Pelican site for a post by "slivel" referencing CV joints he lists all the possibilities that will and have been used on 914s including axles and what mods need to be done to make things work. The bottom line is if you beef up the CV joints and axles then the transmission becomes the weak link unless it is replaced and so on and so on. Steve uses 930 CV joints but since he is running a 3.3L engine (I think?) his 901 gear boxes last about a year of road racing. The trade off then becomes what is cheaper, moving to a stronger gear box which will last for 2 years but be more expensive to work on and of course upgrade OR do a 901 gear box overhaul each year? Experience has shown, at least in the San Diego area to have a race mechanic do a gear box it is cheaper to do the yearly 901.

As a side note I had my race car engine detuned to about 200HP so the 901 boxes would last about 2 years and that was about the same as the right side CV joints. I really liked Eric's product and found they came with grease, boots, bolts and everything. If someone else can do that for sale then I guess some competition might be okay? Eric would have to chime in on that.

Posted by: Eric_Shea Oct 28 2010, 07:51 AM

Same dimensionally... just a different axle and spline count. Why? Don't know.

John, next time out, let's get you GNK/Loebro CV's. Even in race conditions, I'd bet they last longer. I'm thinking you bought CV's when we were selling the Meyles.

How long have most peoples 914 CV's lasted? I don't think this is an issue for most cars.

Posted by: pcar916 Oct 28 2010, 08:09 AM

The 914-6 CV's are splined the same as 911 axles, which are the same length as the -4's. But the CV inner-race depth is the same as the 4 CV's. Interestingly, you can remove 4mm from each shoulder and use 911/930 CV's on 6-cylinder axles if you use the right transaxle flanges and stub axles.

930 Advantage: Huge deflection angle, which is why the off-road crowd loves 'em
930 disadvantage: Weight... lots of it

I ran 930 cv's on 911 axles (with a spacer) for two years with no problems whatsoever. There is plenty of room in the trailing arms for them.

944/951 CV's are splined the same as our 914 axles, but the inner races are the same depth as the 911/930 CV's. Which is why we can run 944 CV's on our cars with the same 4mm mod. and different flanges and stub axles.

Posted by: pcar916 Oct 28 2010, 08:11 AM

14 years with 2.7 and 3.6L motors. But that's with occasional cleaning and repacking... reversing the rotation helps too.

Posted by: rick 918-S Oct 28 2010, 08:13 AM

Then there are conversion cars like mine that have engine/transaxle set back. This builds in CV angles before motion. After checking all my CV's this summer, noting how far to the outer limits the cage body was wearing, and reading through this post I think I may be hyper extending my joints a little more than most. I think I may need to look at 930 joints in the future.

Posted by: pcar916 Oct 28 2010, 08:30 AM

Yep. The only thing about angles more than 5 degrees is that it costs horsepower... which is lost as heat, the increase of which shortens the life of the CV.

It's one reason I'm hesitating to flip one of my 915 transmissions to use in the 914. It places the flange about 5 in. above where it was. Unless the motor is lowered by the same amount, the deflection angle is pretty extreme. Too bad, I like the ring out by the side-cover! Sooo much nicer for carrier/R&P changes. But I digress.

Posted by: Eric_Shea Oct 28 2010, 03:38 PM

And possibly some custom length axles.

Posted by: underthetire Oct 28 2010, 04:50 PM

Just FYI, stainless is pretty soft, not very brittle. ( at least most grades ), think it would be fine myself.

Posted by: LotusJoe Oct 28 2010, 05:13 PM

[/quote]
Even though our engines are type 4,, I NEVER said that those were the CVs we had in our car.(I assumed the maximum angle of a 914 CV is like that of a T4) 914 CVs are dimensionally the same as the T1 mentioned in the 101 site. 914 CVs are some bastard creation that are NLA. I mentioned that the T2 CVs were considered a "drop in" upgrade to the T1 CVs which the good folks here have been modifying to work for us. Just have to check the spacing of the T2 CV mounting holes to make sure they are the same as T1.
As far as "sigma phase embrittlement" concerns, don't use SS for the pins,, the harder the metal the easier it is to snap.

-Robert
[/quote]
Robert, Please don't misunderstand, I didn't mean to imply that you indicated T4 Cv joints go with T4 engines. That was an assumption I made. I wasn't even aware that there so many different joints. The site you listed is very helpful, but for me was confusing. My joints are going on a mildly tune restoration so I'm not very concerned about over stressing the Type 1 joints.

Thanks for your help and input.
Joe