Summarized as "Hey, I overloaded it once, and nothing bad happened. Ergo, nothing bad will happen, no matter how many times I overload it."

Riiiiight.

Mike and Blitz have made some good points about fatigue failure. You might want to do some more research on the subject.

 

I will replace the fender washers inside the trunk with thicker plates. However, the only failures I've seen where the trunk bottom failed were with the older Da'Lan hitch that only had 2 bolts. I also suspect that the tire trailers had too little tongue weight causing the hitch to pull down (pivot) on the bolts instead of pushing up onto the trunk pan when going over bumps. I know that the tire trailers are probably only around 500 lbs fully loaded with tools and tires, but they aren't being pulled at 30 MPH on a flat, smooth road for about 2 miles round trip. Even still, I will certainly keep an eye on the mounts.

In my previous thread, I was mainly concerned about the bolts that mount the bumper rail to the car. After inspecting those mounts with the bumper cover removed, they look to be MUCH stronger than the mounts in the trunk pan. If a failure begins to occur, I think it will be most apparent below the trunk. The paint blobs will remain on the mounts, so any sign of fatigue should cause cracks in the paint before a catastrophic failure.

 

Strange - I thought you were trying to pull a boat with mass up a sloped ramp, which would indeed suggest that there are forces other than the engine acting against you.

I take it all back - if your boat has no mass, then towing it with the S2000 probably won't do any damage.

 

- it works. the end

 

No more.....no more....

Congrats again the gernby that it works. I'm sure he'll keep any potential stress/fatigue under observation.

 

This is getting rediculous Iain. The dynamics of high RPM launches are completely different from that of towing. When towing, the loads are delivered slowly and conservatively, which negates almost all the additional shock and stress of the flywheel. Autocrossing with sticky tires and grippy clutches could easily double or triple the amount of short term torque to the drivetrain with their high RPM rapid clutch dumps. I'm not in the mood to do the math to figure out the amount of instantaneous torque that would be provided by an 18 lbs rotating mass at 9K RPM during a 1/2 second clutch engagement. We aren't dealing with that issue at all here.

 

Don't be stupid. I have explicitly stated that no clutch dumps are a part of this. If you engage the clutch slowly at 3K rpms (with the wheels in the air), then go WOT ... the drivetrain will see even more torque than it does while pulling the boat. However, you will hit redline very quickly, and the torque will end.

 

Resorting to a different argument, since the 1st one didn't work out? Did you not grasp what I was saying about continued monitoring of the attachment points?

 

[QUOTE=altiain,Sep 13 2004, 07:15 PM] Strange - I thought you were trying to pull a boat with mass up a sloped ramp, which would indeed suggest that there are forces other than the engine acting against you.

I take it all back - if your boat has no mass, then towing it with the S2000 probably won't do any damage.

 

I'm just glad no one has resorted to name-calling and forced a mod to jump in and lock this thread.