Bulletproof axles

What are you guys running for axles? I know the GKN axles are supposed to be good. I had a big issue with destroying CV bolts until I got a solid trans mount. I think the weak link now is the stock CV axles themselves. I also believe that my LSD is partly responsible for the fact that I havn't broken an axle yet since it helps prevent the wheel hop that seems to be the real killer.

don't have an answer for you, but could you elaborate on the "solid trans. mount"?

is this the same thing as in one of the random threads in here that showed a crazy pic of a huge brace bolted to the chassis on one end and directly to the side of the transaxle somehow?
if that's the very same, is this a typical fix to bolster the strength and rigidity of the transaxle that tries to destroy cv's?

the only thing i saw on axle upgrades was on another post about the sherman tank axles from GKN that were a limited run that only a few got because of lack of interest at their price; but if i am not mistaken i think you were already on that thread as well?

Well as far as sherman tank axles go, the GKN motorsport axles referenced there are not the same ones I was talking about. The "sherman tank" axles are indeed much tougher and much more costly.

My solid trans mount is nothing near as elaborate as what you were talking about. Truth be told I've never heard or seen anything like that before on a 944. I made my solid mount and it couldnt get any more simple or low cost. I simply filled the stock mount with 80A polyurethane and let it set for 3 days. The transmission doesnt budge 1mm and while it does transmit a bit more vibration into the shifter, its not something I'm worried about. My car has side dumped straight exhaust, 300 lb coilovers with 28mm T bars, and semi solid engine mounts. NVH are honestly the least of my worries.

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lol looks the budget just got overhauled again.

You may not need them gutterboy. How much power are you putting down? I'll be 400+ rwhp and tq soon which is pretty much around where the stock axles start to violently explode.

Well jury's out on that one but here's what arrives in my garage in a week or so.

01 c5 corvette ls1 that was in a sideswiped rx7 conversion. I am probably messing up the following description but I was told that it was further modified with a better cam and a higher flow set of injectors. Lightened flywheel for reduced weight but I probably won't be able to use that for this conversion. I am mating this to a 56000 km 951 transaxle with lsd and external oil cooler. Since the c5 is something like 325hp? stock (slightly more than standard f body ls1) I figure this could be just over 350hp at best till I know what true mods are done on the block. Even though this is to be a street machine I do intend on being a little silly with it. No clutch dumps but if the clutch is out from 1st gear I will be dropping the hammer on the skinny more than once.

Tell you the truth I have been fearing not being able to control myself doing that when this gets built I even pondered downgrading some of the custom mods to keep it at a more reliable hp number where I don't have to worry about starting moving on it.

Think I am going to seriously look into that solid transmission mount more somewhere in this forum.

I can pm you pictures and give you a better explanation of how to do the solid trans mount. It takes about 15 minutes to do plus 3 days waiting, and costs about 20 bucks. You wont have to worry about the axles with 350 hp. Thats only about 300 at the rear wheels. The biggest weak link in our cars is the R&P gear in the tranny which really only factors in when coming off the line and shifting. If you dont drop the clutch or grab gears like a mofo, the tranny wont mind you slamming the skinny pedal in gear ( as long as you have a proper solid mount to prevent it from moving ).

I just sent out a set of the 4340 Chromoly axles. From now on I am only making the axle shafts. The Type 2 CV's can be acquired from GKN or Empi. GKN's are better quality ($$$) but the Empi's cages can also be upgraded to chromoly as well. The factory axle shafts' inner stress risers located right at the inner CV C-clip are what snap first under V8 torque and are the weakest link.

I'm running the vanagon axles have not had any problems to date (knock on wood).  I'm 350 to the wheels on my lightened track car.  I do not dump the clutch on this car, no standing starts to date.

Installing any axle that is not heat tempered of a material that spools (gives under sudden torsional force), your trans is taking the instant torque abuse.

Hey dougs951s can you pm me pics of what you did with that 80a polyurethane stuff?

Xschop I sent you a pm inquiring about several of the renowned top quality products you make. Thought I saw some sort of billet block you made to reduce vibration. Was that for this solid transaxle mod?

Also is dougs951s method for the solid transmission mount the general consensus on how to do that mod?

That crazy metal brace I saw on another thread was said to be a bad idea from carreragts.

Done endless advanced searches on this and the whole bump steer conundrum. Seems to be a lot of different ways to skin a cat in each of these.

Just trying to become as schooled as possible while I procure parts and before I get kneedeep and completely lost in piles of parts.

One last question.  Both of you guys made reference to the premise of 'if your not shifting gears like a mofo the 951 transaxle should be fine'

Back when my 944s ran with the original engine I pushed it pretty hard for the 30k km's I ran it for. I did end up having to wait a half second to shift into second gear cause my synchro was starting to go.  Now the na transaxle is much weaker but can this kind of fairly quick shifting kill the 951 too or is that just typical for an na transaxle to suffer from the way a turbo transaxle can and should be driven?

dougs951s can you also pm me pics of what you did with that 80a polyurethane stuff?

I've had no axle issues at all with my swap, currently making 400hp to the rear wheels.

I followed this procedure for my late tranny mount, worked great.

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Rich

Thats what I used also, its a modified version of the "kelly mount" some refer to as the "kev" mount. Works ridiculously good for how cheap and simple it is.

I'm running my own semisolid engine mounts which are the same idea. First, I cut open the stock motor mounts and drained the oil. Then I stuck a rubber donut inside to give it some compliance and filled the hollow around the rubber with 60A urethane just slightly less stiff than what I used to fill my transmission mount. Cheap, easy, effective semi-solid mounts that do their job without transmitting as much nvh as true solid mounts.

sooooo..... you did the drain the oil and rubber then fill with 60A on the stock porsche motor mounts or eric's ls1 conversion motor mounts?

you are running an ls1 aren't you? and if so did you mod the existing porsche motor mounts to work with mounting plates you fab'ed for your ls1?

little confused.

Probably going to get flamed for this, no I'm still running the factory M51 4 cylinder engine. I like to come here because you guys think outside the box and do things most of the turbo 4 guys would never think of or condone. I love what you guys do to further the platform despite the fact that I am not, in fact running a V8.

Flame suit on.

dougs951s wrote:
Flame suit on.

Why in the world would we flame you just because you are running 1/2 of an engine  

Lol sorry for blowing your cover. That is the exact reason why I had been a guest for a couple of years and only became a member once I bought my c5 ls1 and 951 lsd transaxle.

Engine shows up tomorrow which will be sweet.

Only missing deluxe conversion kit from tpc, wilwood brake Mc, wilwood front big brake upgrade, and hopefully a package of parts that just make sense for odds and ends from xschop for bump steer and solid transaxle mount vibration.

Thanks for the kev14 mod link

Good luck on the swap gutterboy, a good friend of mine on this board is finishing up the final stages of his swap and I drool over his car every time I see it. I think I'm almost as excited for his first start as he is, I cant wait to see how his car compares to mine. I (currently) have the advantages of better brakes and suspension and ~100 whp, but his car weighs less than mine and that braking and handling gap isnt going to exist for long. He also has a huge cam waiting to install so in the end I think his car will give mine one hell of a run for its money. To answer your earlier question about the transmission surviving hard shifting, thats hard to say. I'm pretty gentle with my car around town mostly because it simply has no power below 3500 rpm and there isnt much point in driving it aggressively. When I'm out to romp on it though, I drive it like I stole it. Thing is, even with 350+ lb-ft at the wheels, when I shift hard it takes a split second for the torque to come in again so the transaxle isnt taking the same kind of abuse it would if it were shifted that way with a V8 in front of it.

I still make the chromoly axle shafts (85.5-up cars) ($335 shipped US-48) and I also have the Billet/polyurethane mounts for 85.5-up cars ($225 shipped US-48)

I have sold many here to the hybriders because the V8 will quickly break the axles/cv's if these two items are not addressed. Thanks, Rob