[Here's My new project: a diy dynamometer]

Hey group:

This is really cool!! I have kicked the idea around for years to try to build my own dyno and was excited when I saw the subject to this thread. Unfortunately, it seems a little beyond the average do it yourselfer's capabilities.

Years ago, when I was roadracing motorcycles, I worked for a machine shop specializing in working on racing motorcycles, it was small. We did some work for some guys racing go karts with Briggs and Stratton (S?) engines. We began to do development work and rigged up a crude dyno. It was a power steering pump off a car bolted to a fixture that allowed us to attach the briggs motor to the drive pulley. We had a reservoir of hydraulic fluid hook to the lines. On the outlet from the pump we had a pressure gauge. We could run the motor at a steady speed while making changes and if the pressure went up on the gauge, we knew we were making more power.

I know it, like I said, it was crude. But it worked!! There was no easy way to calabrate it to give HP numbers, but as a tuning tool it was effective. In fact, the motors we were working on began to be more competitive and others from the same league began to show up at the shop asking about getting some work done.

Unfortunately, as we learned to build and tune these lawnmower engines to ever higher degrees of tune, the short comings of our little dyno began to appear. We began to blow hoses under higher pressure and the fluid began to get very HOT!!!! We replaced hoses with stronger ones and even considered rigging a cooling radiator for the fluid. We were pushing the limits of the pump and considered a bigger hydro pump. In the end the shop moved onto other projects and the idea was dropped. But I never stopped considering assembling something similiar for my bike engines. I've even considered using an electric generator instead of the hydraulic pump and feeding the power back into the grid! Just some crazy ideas.

Momentum dynos that test rear wheel HP are great, and my hat's off to you for building this baby, but a engine dyno that the engine can run at a steady RPM while changes are made is the only way to make many incremental changes and see the results immediatly. Yes, it's harder to pull the engine and mount it to the dyno.

sorry for the long post

[roadracing class]

Hey group:

Just wondering... does anyone know what sanctioning body and class John C. raced his rusty old Datsun in? Also, what SCCA classes do people race 280Zs in now? Are they competitive? What class would a 280z fit into if it had coil overs and stand alone EFI. What other sanctioning bodies do folks roadrace their Zs?

[rack replacement]

Hello everyone

I have a 280Z, manufacture date 6/77. It has stock L28. The steering has about a quarter of a turn of slack. Getting ready to rebuild entire suspension. Have searched this site and the internet. Does anyone know where to purchase new or rebuilt steering rack?