johnjw

After about 3 good years of endurance racing we now are having axle issues like crazy!! Our car has won many races but now we can't get axles to last very long. Went through 4 drivers sides and 1 passengers side this last weekend.

I've tried to keep them oem and rebuild them but it still doesn't seem to hold up even using redline CV-2 and venting. We went through a set of "500hp" Insane Shafts early on in the race.... like 15 laps @ ORP.

Any suggestions? I've set the car at ride height and they are not bottoming out in the inner cup so thats not an issue. My best guess at the moment is going with bigger brakes with more thermal capacity. We're currently using 10.3's up front. Nothing else on the car is weird/bent/shiftng around. The outters just get so hot that they end up welding themselves together.

spsspeed

These guys built all my axles, had good success with them:

Gator Axles: All Cars Front and Rear Axles, POSI, Racing & Drag Axles

90civichbsi

iTrader: (1)

What car and what brakes are you using? It is sounding like heat soak from brakes to me. I would also check your wheel bearings. If you are overheating axles more then likely your wheel bearings are shot. Also play in wheel bearings can cause your brakes to drag creating more heat.

Since the axles are overheating and welding themselves together I don't think any axles will fix the problem. It's the brakes or something else.

I have been running into the the same issue on bigger tracks like COTA and Texas World Speedway. I was using the stock 9.5" brakes with good pads, fluid and brake ducting. It's still not enough when high speeds and heavy braking are involved. I have been breaking axles left and right. At TWS I could make axles last if I backed off my lap times by 5-6 seconds, but 2 consecutive hard laps were sure to break them.

I recently upgraded to insane shafts 500hp axles and the driver's side outer CV broke after 4.5 laps while in the middle of 5th on the back straight at COTA. My driver's side wheel bearing also has some play after just 3 track weekends. Insane shafts sent me a new axle, I am upgrading the the 11' wilwood 4 piston brakes and replacing wheel bearings and hubs this weekend. I also repack my wheel bearings with Neo Synthetic 800 degree grease and it wasn't enough to make them last.

90civichbsi

iTrader: (1)

Driveshaft shop offers some interesting info regarding venting and grease that could also help. You wouldn't want to vent the inner joint because it'll act like a pump for the grease inside it, but it would work on the outer joints. When the axles have blown does the boot look like it's suctioned in? If so venting could help.

The Driveshaft Shop Blog ? What Makes a Driveshaft Shop Axle So Much Better?

3. Venting On axles that will see very high temperatures we will install a vent tube in the boots. At certain temperature the grease will start to vapor and blow up the boot like a balloon. We have been venting boots for some time and it will definitely save a boot and CV from destruction, its just not wise to do this with a standard application as the vent can also let in certain things.

4. Grease We are using a certain grease that Neo has made for our higher end and road race axles. This grease during testing years ago, allowed a cheap China CV joint to last an entire Road Race on a high end Integra that we were sponsoring. Since then we have seen complete failures of the boot only to have the grease stay in the CV for the rest of the race. It’s expensive but it is the best that we have seen. I’m sure there are others out there like this but we found this to work best for us.

johnjw

car is a 92 civic hatch w/ higher compression b18c5. brakes are from a DC LS Integra using Porterfield ST43 pads. I'm also thinking its a heat soak issue. Also we are venting the outter boot. ;Last time I checked the wheel bearing felt fine but I will be replacing them before the next race. Thanks for the imput so far!

flip_nl

Neoprene boots?

BlueTeg

iTrader: (2)

Had a very similar problem as you. First few years I raced my car were fine. Then all of sudden I started cooking axles just about once a weekend. It was ridiculous. I tried Insane Shafts as well since they came highly recommended by the HC guys next door in Southern Cal and their "500 HP" axles with the special road race prep lasted a total of about 60 minutes on track (10 minutes for practice, 15 minutes for qualifying and they pooped out about 30 minutes into the 2.5 hour enduro we were running that weekend) forced my teammate and I to retire the car and essentially cost us the season championship that year. The owner of Insane Shafts was a nice enough guy, but they are just not up to the task of road racing.

I called the guys down at Hasport to see if they had any ideas since the Autozone, OReilly, and NAPA axles weren't cutting it...and the aftermarket Insane Shaft axle was not cutting it either. He had me source a set of used OEM axles and bring them in for their road race prep which I believe included a very thick moly grease, thicker CV boot, and no inner boot bands. Voila, over night cured our axle problems. Vehicle application was for a 92 Civic hatchback (H2 spec) running 190ish whp before the HP cap and 165 HP after the cap.

Another local Arizona guy who successfully ran the 25 hrs of Thunderhill last year (or the year before I can't remember), did the entire race in his H2 spec EG Civic coupe on ONE SET of OEM axles with Hasport prep. Unreal! I think I've been on the same set for the last 2 seasons.

If you can source an OEM set, give them a call and see what they'll charge you to prep them.
If you cannot source an OEM (mainly the OEMs have the colored rings painted onto the center of the driveshaft), PM me and I can see if the guy who helped me source all of my OEM axles (I've now stockpiled three or four sets) is willing to find and sell you a set or two.