View Full Version : Wrist Pins

02-12-2010, 12:26 PM
I am building up a 63 259 from a Wagonair, (it'll be a 289 when done). I am looking to improve performance any way I can. The engine will be naturally asperated.

I am planning on using half dish hyperutech pistons and using modified pins so they may be pressed in and loose the pinch bolt in an effort to reduce reciprocating mass. Does anyone see a negitive on this and where is the best place to get pistons? Best as in strongest hyperutech.

Jon Kammer

02-12-2010, 12:58 PM
Yes, it can and has been done.

No, the difference in streetable NA engine performance will be un-noticable. The lessened inertia from the pinch bolt will only be calculable at RPMs past that at which the Stude rod big end begins to stretch and lose oil pressure and bearings.

If building a turbocharged or supercharged engine where the RPMs would be held below 6,500 and using some forged piston interchange where the pin diameter is larger, then Ted Harbit and some others have found this to be a usable modification. When money becomes available most of the Stude racers go to Howard, Carrillo or Cunningham rods.

Maybe, you should tell us what you are doing for heads and induction. Over on Racing Studebakers, there are threads-upon-threads of how-to.

Bottom line, after reading all there is, the recommendation will be to spend your first $2,000 engine dollars on professional head and intake porting and valve work. Only after maximizing the intake and exhaust will small changes such as removing the pinch bolt really make a difference.

thnx, jack vines