2000 SJ Compression Question

[RobSki]

Just recently purchased 2000 SJ and was looking for some info on compression, dome size etc.

Here is what I have done so far:

Motor: 701 bored out to 760 (84mm) 62 T cases, 61 X cylinder
Motor is ported for freestyle(bottom end) so I've been told.
Ada Girdled Head with 38 cc domes
Factory B pipe with Mod Chamber
Dual 38 Mikuni's with Jetinetics Flame arrestors

I measured the compression with stock cylinder head and got 150 psi in both cyilnders.

After installing the girdled head with 38cc domes I'm getting 132/135 psi in cylinders. Is this an acceptable ratio or should I be looking to run a higher compression ratio? What dome size should I be using? I'm only able to get 91 octane pump gas... How does this afffect the above choices?

Any info would be greatly appreciated

 

[OCD Solutions]

I run 34cc domes to get 185 psi on a similar setup. The porting changes your compression so every ski may be slightly different. I don't like going over 185 psi myself.

 

[puppy]

Must be the port work for 38 -760 at 135psi

 

[RobSki]

Hey guys,

Thanks for responding... Any other advice, info or recommendations would be much appreciated.

 

[Mark44]

Check your squish when you achieve your compression you are looking for.

Mark44

 

[puppy]

Is the stock head milled ? looks like ada domes 33 next