vrt 300whp with stock diff?

[MEKA NECK]

I am getting into a kinetics kit, and was told its about 300whp. I plan on romping on it here an there, but not beating the piss out of it all the time. Is there anyone ou there that is running stock trans with a vrt setup?

I assume it can be done with a beefier clutch and pressure plate.

[MEKA NECK]

[masterqaz]

plans can be broken lol but a tonne of ppl are rocking stock diffs

your assumption is correct, stock clutches/pp are actually pretty good. Id burn up what you got first unless you have the trans off for somereason

[MEKA NECK]

I do have te trans off and am Freshining up my motor while shaving my bay. I wasnt trying to spend money on one unless I really needed to. Would just a stg 2 clutch be ok, or would that put too much stress on other areas of the trans?

[masterqaz]

That'll be fine, Im running stock disk and P plate right now, holds 10 pounds just fine. Bet it'll hold 14 fine too although im loosing torque with my short runner.
clutches speak torque, thats what cooks them.

[mojavebeige]

Like the title, the one bit you have to watch is your ring gear rivets. That is the weak part of the vr powertrain. Heavy launches with 300hp can shear them, 250 is the big start to watch out point. You will want to replace those.

[masterqaz]

Like the title, the one bit you have to watch is your ring gear rivets. That is the weak part of the vr powertrain. Heavy launches with 300hp can shear them, 250 is the big start to watch out point. You will want to replace those.

If your wasting that much time you might as well slap a lsd in the trans. otherwise just break em and toss another throw away tranny in.

Even with heavy lanches I dont think they're as weak as you think. That wheel is going to slip transfering torque to nowhere, thus lessening the torque on the rivet. Maybe at a sticky track but Im pretty sure this is going to be a street car and the op plans on not beating the piss out of it.

[mojavebeige]

ARP ring gear bolts are 70 bucks I think? upgraded lsd over 700? The bolts are cheaper than a disposable tranny. It is just labour hours, for good reliability. OP asked about the trans. If clutch is already coming out and replaced then the trans is dropped., I see no reason not to other than laziness. Offered my peace and the reasons why. He has a turbo, will probably put the pedal down some time, if the tires break loose and it wheel hops, that shock loads the rivets and pingpingping!

[masterqaz]

ARP ring gear bolts are 70 bucks I think? upgraded lsd over 700? The bolts are cheaper than a disposable tranny. It is just labour hours, for good reliability. OP asked about the trans. If clutch is already coming out and replaced then the trans is dropped., I see no reason not to other than laziness. Offered my peace and the reasons why. He has a turbo, will probably put the pedal down some time, if the tires break loose and it wheel hops, that shock loads the rivets and pingpingping!

ill let you know when mine never break.

[MEKA NECK]

I may put those bolts in, only because it's out and in the long run will be less than a LSD. You all make good points, and yes this is going to be a street car. Every time I take something to a track I break something haha.

So the verdict is yes I can keep stir stock diff, but am
Installing those arp ring bolts for good measure. Installing new stock Sachs clutch and keeping
Stock PP, and having flywheel resurfaced. This sound like a decent plan?

[masterqaz]

Sounds good to me, I personally wouldn't waste the time on the bolts, the bigger your a/r on the exhaust housing the safer those rivets on the diff will be.

Just me though

[JohnStamos]

FWD+open diff+300whp=useless. But,


The weak point in the stock diff isn't the rivets. It's the roll pin holding the diff pin in 20x more often then the rest of the issues. After that, it is the spidergears galling on the shaft from one wheel peels, and shattering, and thats only if the roll pin holds up to that as well. Then the rivits letting go. And finally the entire diff pin shearing in half.

You can pull the trans apart, clean, double roll pin the shaft, add ring gear bolts, clean again, inspect all the wear parts, clean once more, reseal, and throw back together for under $100 and 3hours of work if you already have the trans out. It's VERY worth it.



Stock Pressure plate is a terrible idea. The straps let go like it's their job. At least use a plate with uprated rivets holding the straps, and extra straps. Or drill out the rivets and use high grade hardware. Stock sachs disc takes a beating. The other stock disc's are a grenade waiting to happen. The luk discs and such have literally 1/5 the rivets holding the Marcel to the center section as the stock disc.





Also, if the car wheel hops, then catches traction, the diff rivets are the least of your worries if you are in 3rd or 4th at the time, as you are going to strip it right off. And if you are getting wheel hop in the first place, you need to fix the issue.

[masterqaz]

He knows whats up

[MEKA NECK]

So what clutch/pressure plate would you personally reccomend? I'd really like to avoid putting a diff in right now.

[mojavebeige]

Thanks for that info Stamos, I haven't torn apart my trans or looked into it really, so all I knew what what I was told when I was doing my engine. As for wheel hop, well, to fix that is in the replacing of them crappy rubber bushings. Not talking the loud banging type, but just the tire spin chatter if you get moderate spin.

Edit: Looking into the issues Stamos mentioned, found this nice little article. Basics, but if don't have the cash to put down the full lsd, can follow what these guys do for more strength. http://www.vwtransaxles.com/diff.html

[MEKA NECK]

Thanks for that info Stamos, I haven't torn apart my trans or looked into it really, so all I knew what what I was told when I was doing my engine. As for wheel hop, well, to fix that is in the replacing of them crappy rubber bushings. Not talking the loud banging type, but just the tire spin chatter if you get moderate spin.

What rubber bushings?

[mojavebeige]

I say rubber, but might be eurethane. Never concerned too much to figure out the oem ones since replacing mine when I do my diff and vrt. Control arm bushings. etc. That is the cause of wheel hop, excess movement in these bushings. Due to physics, is why independent suspension components are so suceptible as the control arm starts to walk. It is really noticable when one of those bushings fail and the control arm just walks wherever it pleases, however, if you get chattery wheel spin, it is the same thing, but less violent feeling since the "walking" is less pronounced. If the car has any suspension, it has bushings. it absorbs the minor vibrations, misaligns and twisting forces to prevent shock fatique.

[JohnStamos]

Yep, switching out the front control arm bushing with poly, and the rear bushing in the front control arm with r32's DRASTICALLY cuts down on wheel hop. Avoid poly in the rear, unless you ONLY drive the car 1/4 mile at a time, as they are great for 60' times and avoiding wheel hop on slicks, but terrible for handling, ride quality, road tracking, and traction on uneven surfaces, ect.

Good engine mounts help as well, as they help eliminate axle wrap. Stage ones from BFI are a good choice.


GOOD tires are great to help the stock diff live, as its usually wheel spin that kills them once you take care of the weak roll pin. The spider gears just can't handle 1 wheel peels, and as much as it seems like our cars do a good job of spinning both tires, they aren't doing as well as it seems.

[MEKA NECK]

All great info. I see people are breaking gears and trannys even with diffs! What can you do for the best bang for your buck setup!? I'm not trying to replace transmissions as often as I do my oil pans

[mojavebeige]

Well, from the info gathered, and you dont have the bucks for an lsd, follow what those guys in the link I had before do.

Spider gears
Ring gear bolts
Double pin the cross shaft roll pin

Replace your control arm bushings with something a little more firm, this will help prevent chatter if you get wheel spin. People can talk about driving nice and all that, but I mean a VR regardless of tune, if you are a driver, a person will get on the throttle. By keeping that control arm closer to where it belongs, you reduce wheel hop, and therefore vibration transfering into your dif. Kind of like a safety net.

[MEKA NECK]

Well, from the info gathered, and you dont have the bucks for an lsd, follow what those guys in the link I had before do.

Spider gears
Ring gear bolts
Double pin the cross shaft roll pin

Replace your control arm bushings with something a little more firm, this will help prevent chatter if you get wheel spin. People can talk about driving nice and all that, but I mean a VR regardless of tune, if you are a driver, a person will get on the throttle. By keeping that control arm closer to where it belongs, you reduce wheel hop, and therefore vibration transfering into your dif. Kind of like a safety net.

Ok so Poly On the round bushing on the control arm that sits like a dount, and an R:: bushing in the rear, the one that sits like a barrel? Correct? Also, this is in my mk2, and I kept all my 4 lug suspension.

Where can I purchace ring gear bolts, and spider gears.And double pinning the cross shaft roll pin is just something I do myself, I cant buy the things needed for that?

You have to bear with me, I am very overloaded on info at the moment, and just want to be crystal clear with everything.

[mojavebeige]

Aaah, a mk2! I don't know their suspension, but whatever is correct for your control arm in upgraded bushings is correct. Remember that you want some flex, but poly is the standard for the material.

Was hunting, doesn't appear that anybody outside of vw sells the spider gears. I did some searching, and couldn't find anything. Also other forums have commented on the previous link in the past and they have neg rep in vw community. So for stock diff, all I was able to find doable would be double pin the shaft and those bolts.

The bolts themselves are easy, ARP sells them, the hard part is removing the old rivets. Also make sure you align the same bolt holes up again to ensure proper gear alignment, never hurts to be extra careful. I cannot find specifics on the how to, but the way it appears is that the double pin they use the factory one which seems hollow and put a smaller pin inside that to thicken it up.

Really there is nothing for the car to upgrade the oem other than the bolts available that I can find.