I plan to put a 518 behind my new build and was wondering how strong it was through the OD unit when not in OD. As I understand it, the OD clutches have to hold all the power with spring pressure. My next build will put 500+ horsepower to the rear wheels. I plan to baby it in OD so I am not real concerned about that, but I was wondering about it's strength in 1, 2, and 3.

Your experience and any tips on this would be welcomed.

Thank you!

Use diesel guts in the OD. Should be able to use the 10 disc clutch pack out of a 48RE with the proper reaction and apply plates. Also replace the thick plates for the OD brake pack to add more clutches for more holding power. PATC trans offers a stiffer spring for more apply pressure. FWIW, I think it would not be needed in your application. The diesels are producing twice the torque at the same power level and usually don't give any problems.

My friend has a street car that runs 11.0's at 121 MPH with a 440 and the OD guts are all stock, no diesel parts.

Thanks for putting my concerns to rest. If I happen on some diesel OD parts, I will grab them. But it is real good to know that there is not any concern on using the 518 without them. Although I do plan to make the mods suggested here and in other threads.

Thanks again.