Jeff Adkins' 944SS SP

Last season, Jeff, bought a 944 kit and taper-bored stock carbs from MPS.

With the experience we've gained with my jet-kit, I was able to send him something that he bolted on and rode until this year.

Disclaimer time!!

I always encourage people to take their kitted or taper-bored carbs to a shop that has a dyno to make sure that the jetting is correct. Just because Jeff had good luck with his carbs, doesn't mean that my recommendations change.

When Jeff brought the bike up here, Fred performed a baseline test which showed that it made 85HP. (That's Fred Snyder, whiz-kid, who's been working with me for 2 years.)

That is excellent for a drop-on 944 kit and modified stock carbs. The baseline is used as a comparison in the following dyno charts.

My first thought was something like; 'how the heck am I going to make much improvement over that?'

Jeff wanted me to port the heads, adjust the cam timing and ignition timing, and finish the tuning on the dyno. So, I did.

The first dyno run was very encouraging.

Checking the dyno run numbers you'll notice that they are #3 and #5. Run number 4 was an all-gear run.

At this point the jetting was a bit rich (in spite of what many people feel is intuitive, the jet requirement rarely goes up when compression is increased, less restrictive exhaust is installed, or porting is done.)

Fred lowered the main jet and, in the process of removing the carbs several times, eventually installed new needle jets (there's a secret there!!!) Finally, he retarded the ignition timing 3 degrees (another of my recommendations to customers who install high compression pistons.) The torque picked up a little and the power only a smidgen, but with 205PSI compression, I like the idea of retarded timing.

The result is shown below. Check out the torque!

Keep in mind that this has modified stock carbs, ported heads with stock 900SS cams and modified stock manifolds, a stock air-box/ battery box without a top, (just the filter frame) stock exhaust pipe with 'Forza' slip-ons.

Reed's cryin' (why did I buy all those 'kool' parts to get less power than that?), Michael Feldman is sourcing new exhaust components. I feel bad for those guys, but maybe we're just getting a little smarter?

Feldman's M984 will like a 'glass-pack' muffler. (Another tech report about that, soon.)

And Reed's hasn't been on the dyno for 3 years. It's gone together with ST2 cams, and should be pretty good this iteration.