dumb A1 vs. A2 questions

[evanwebb]

OK, I will freely admit that I know nothing about A2 cars, so I have these questions that relate to a future enduro car that would not be a standard IT car. Basically I'm interested in putting A2 front bearing carrier & hubs & 10.1" brakes on an A1 for better braking and more durability. I would retain the A1 control arms. Can I just swap out the A1 bearing carrier and associated hub assembly for the A2 part? Are the ball joints the same, the steering knuckle, etc.? The axles? thanks in advance...

[Greg Amy]

I can't answer your question directly, but I can tell you that rear discs from a 1986 GTi will bolt right up, as will larger front brakes from the Scirocco 16V (and will fit under 15" wheels.) - GA

[mrjones2]

I think you may have to change axles as well - the early ones were 90mm & later ones were 100mm. A2 has better steering arm location on the bearing carriers, less bump when you lower the car....

Kendall

[evanwebb]

I think you may have to change axles as well - the early ones were 90mm & later ones were 100mm. A2 has better steering arm location on the bearing carriers, less bump when you lower the car....

Kendall

OK, here's how ignorant I am: does the 90 mm or 100 mm refer to the CV joint diameter? I think I only care about the spline going into the hub, is that spline also different between the A1 and A2 cars? Are the axles difefrent lengths also? thanks...

[evanwebb]

Thanks Greg, yep I understand what to do to the back of the car since I have converted my H Prod car to rear discs.

[Lael Cleland]

Ok, Here is the deal. MK2 BJ's are the same size as late MK1, 100 mm hubs will except 90mm axles, but 90mm hubs & 100 CVs dont work, The strut is different, the mk2 is wider,and the 2 bolts holes are not the same... MK2 strut housing should work...
Also ya need 16V GLI, Carrodo or MK3 spindles to have big brakes.. The mk2's have an integral carrier, 9.4 only...

Been there, tryed, gave up, LOL...

Edit: The splines are all the same, there are some goofie outer CVs That 90mm, but wont fit MK1s...,

[shwah]

Did the 16v Scirocco have the large hubs? They came stock with 10.1s, rear disks and the ideal larger master cylinder. If the hubs are big ones, that is the easy button.

As noted if you use late A2 carriers (the early ones have small hubs too), the A2 strut tubes should work just fine. The A2 16V Jetta's came stock with 10.1" brakes, so that is what you are looking for if you go that route.

The 10.1 caliper setup has a tendancy to bend/banana the inner brake pad, causing it to wear out faster than the 9.4s. I don't know how fast/heavy the car is, but well ducted 9.4s with very aggressive pads and wheel fans may work fine, and have longer pad life.

[evanwebb]

Hmm, between what Lael and Shwah said maybe I should start with just converting to 100mm hubs and the vented 9.4" discs from a A1 GTi... The car will be about 1900 lb but have a lot of horsepower so I expect the braking demands to be quite a bit more than an IT car.

[Flyinglizard]

Our A 2 Chumper runs the A3 stuff. Hubs, bearings brakes. 14 in wheels still fit. Basset 13x8 also fit.
1820# empty. Works well.
My book covers the Chumpcar and road race stuff pretty well. .
MM

[Lael Cleland]

I had a 16V scirocco ITA car, with the small 64mm brgs & welded diff... It was always breaking hubs,brgs, & snapping the threaded part of the CV joints off all the time. Now the guy who ownes it, has an open diff, and has only lost 2 hubs so far in 1.2 years.. !!BUT!! I drive or over drive cars very hard! The 64mm MK1 stuff is good for 100-110 whp... The ID of the brg is about 4mm smaller than a late MK2, with the same spline size as all vws, so the MK1 hub is thinner/weaker...... MK2 & MK3 is 2-3 times stronger than MK1...

[Flyinglizard]

I think the standard fix for that is the Quattro/Dasher hubs and bearings.

[Lael Cleland]

as far as I can tell, the audi/dasher brgs are 68mm.. MK1s are 64..?? I hope I am wrong, we need a cure for the weak hubs!

[Dave Zaslow]

as far as I can tell, the audi/dasher brgs are 68mm.. MK1s are 64..?? I hope I am wrong, we need a cure for the weak hubs!

Lael, you are not wrong. The A1 knuckles need to be machined for the larger diameter bearing and snap rings. The new hubs do not have the same stress riser as the A1 POS. This is not legal in IT (but you know that). The other cure for A1 hubs is to overtorque the axle nut significantly (twice book torque) and change them every two or three races.

[shwah]

I think you mean over torque the hub nut correct?

[Flyinglizard]

Whats 4mm among friends?
Many of the original cup cars had the bigger hubs. Who cares about the rules if the wheels dont fall off?

[Lael Cleland]

We torque ours to about 300ft lbs & check every time we head back on the track.. I have also been jamb nutting them, no failures yet.. 85-88 mk2s are 66mm.... 2mm would be easier to bore...??.. Also removing material from a spindle make me nervous, wouldn't it make the spindle weaker in another place?
The other thing I have found is used, old , rusty mk1 hubs are better than any thing you can buy new.. Just make sure the portion that the inner brg rides on is not smallend up or worn.. A small amount of wear is ok but if its .5mm smaller, its not so good...

[Flyinglizard]

The spindles bend the steering arm a lot @ small impacts, but I have never seen a failure. They are forged, pretty soft, wont break. I have had one get the wheel pounded through the firewall, never broke the spindle.
Any bearing /hub is an improvement over the stock A1.
I still run my A1 on stock , repacked bearings, with a welded diff. Most of the cars that break the axles a lot, have the camber plates that result in the axles hitting bottom. If you have my book , it tells about centering the engine and verifying the axle play/plunge.
I take the camber @ the knuckle and not at camber plates. I add castor at the tops.
The 88+ bearings are real strong. The Mk 3 are even more.
I have no idea how you can break the axle ends off at the threads. Way over tight? maybe. Try less tight. I use a 24in breaker bar every morning, stand on it. Might be 200# or a little over.

[Lael Cleland]

My old 16V scirocco was the CV snapper, it had a welded diff, it seamed like the right side kept getting tighter, and the left got looser... It was weird, our tracks are mainly right had turns here... Also I am to blame for that, I use the gators, often the car was completely air born... Landing the thing with full throttle, i think, made the splines wear, cause a little slop, and tighten the right, loosen the left..

My rabbit has a peloquin, last year I was fighting the axle nuts coming loose, I installed brake ducts(to cool the hubs, not brakes) and did the jamb nut thing, haven't had a problem yet this year! BUT my buddie raced it and parked it sideways on the track in front of a Miata, the spindle did bend....

Now the axle bottoming out, I have found a cure, not exactly legal, but works... 100mm golf axle shaft is slightly shorter... Its hanging on my wall next to my window welded mounts.. LOL....

[Flyinglizard]

The reason that we welded the car was the gators. I can now go way inside of the gators, wi th the inside wheel.
It matters a lot @ Sebring . The track is so rough in the spots that I need power down.. Plus it rains. rain and welded are very hard to beat.
MM

[jrez]

I have also been jamb nutting them, no failures yet

Jamb nutting = double nut?? Any type of locking compound been proven to work well??

Interesting stuff.