SXR Head CC question...

ddjernes · Jul 10, 2013

I have an 06 SXR that I rebuilt the motor on last year. Has wiseco pistons with a little larger bore. Went with an R&D 29cc head since the stock head was trashed. The cylinders are heavily ported. Running dual Novi 48mm carbs as well as a factory dry pipe. Now to my question.

I currently have 150psi in both cylinders with the 29cc head. I want to change to a billet head with interchangable domes but would like to get my compression up towards 190ish. I think that should be safe for 93 octane. What size CC dome will I need?

kx454 · Jul 10, 2013

180-185 is the most I would go with pump gas....unless you don't plan long wide open runs. 26cc-ish domes sound like they are in your future. I run an ADA head with 26cc domes and a skinny base gasket and pull 210psi at 1200 ft. My boat is only mildly ported though, I have an ADA head....the domes are like 35 bucks a pop as opposed to JSU/Kommander that are something like 85 bucks.

ddjernes · Jul 10, 2013

Thanks, I will go for 26 then and see what happens. ADA was what I was planning on running. Do you think going girdled is necessary?

ddjernes · Jul 10, 2013

Also, where is the best place to get a good deal on an ADA setup?

SJ 701X · Jul 10, 2013

ddjernes said:
Also, where is the best place to get a good deal on an ADA setup?

JetManiac, Not sure if he carries Kawasaki but I know he carries Yamaha.

wanderer1 · Jul 10, 2013

Even with 93oct I would'nt go over 180psi with the dry pipe running it hard. I think you'd be better off and get more bang for the buck getting a programmable ignition rahter than uping the compression. Just my .02 cents. I ran 180 with 93 on my Blasters and it was fine,my SXR motor has 220psi static cranking compression with heavy porting and is hell on the crank and such. Advent or Igni-Pro is what would be in my future if I were you.

ddjernes · Jul 10, 2013

The ski has a TON of top end. But the bottom end is lacking. If i went with programmable ignition could I advance the bottom to give it some balls?

wanderer1 · Jul 10, 2013

Yes thats what a programmable ignition is for,advance and retard the timing where you want to.

ddjernes · Jul 10, 2013

How hard is it to program? I'd hate to blow up the ski...

kx454 · Jul 18, 2013

I would go lightweight flywheel before an ignition...much better bang for the buck

Marsig58 · Jul 18, 2013

With the Kommander Domes a 29cc dome puts you around 165psi. In regards to the ignition give Art a call from Jetworks Performance, he re-programmed my Advent T3 to suit the ported 820 motor he built for me.