98 srx 700 motor mod question. 2 base gaskets + decked head!

[woodyy69]

So I blew my center piston the other morning. By fault of previous owner so I found when I took the motor apart and had 3 new pistons and they must have pit a bad cylinder back on because there's chunks in the cylinder wall(ring chunks bec its harder then the piston metal) and no chunks out of the piston and rings are still intact had 70lbs compression still. Never wrecked anything else because it happened as I was pulling in the dooryard. Note the other 2 cinders still had crosshatch marks in the cylinder. And the piston were brand new pretty much.

Ok that's my rant for today and has nothing to do with my question lol

My srx is a 98 700 . And I'm wondering about the 2 base gaskets and milled head trick for some extra hp. From what I understand you put 2 base gaskets in and mill your head 30thou. Correct me if I'm wrong plz.
And do I have to 're-jet? I'm at the borderline of running a little lean and having to rejet now with fins taken out of my mailbox and a set of hauck growlers. Plugs are a darker tan colour running br9es. I have a set of 10s for nights below-30c.

I would like to do this while I got my motor apart waiting for another cylinder and 3 Yamaha pistons(OEM all the way for std bore!)

Any help tips and do's or stay out of it all together would be a great help!

And I just want to say this is an awesome site and you guys have helped me out alot! Props to yas!!

 

[mrviper700]

let me tell you why its a waste of time, the only thing your doing is raising the cylinders .020" thats a half a millimeter(thats really nothing). your cutting the heads has more benefit then does just raising the cylinders that little amount. The part that hurts you is that you create extra deck clearance you cant remove from the added base gaskets no matter how much you cut the heads, the piston will now be down from the top of the cyl at TDC .030-.032" because you have .010-.012" deack clearance stock. Thats dead space...........

you be better off to just mill the heads a tad bit and the added compression will be the gain in power. set up the heads to yield .055"-.057" squish.

run it.

 

[woodyy69]

Ok sounds good! So mill my heads would be a good idea? What do you recommend for a head cut?
Thanks

 

[mrviper700]

Ok sounds good! So mill my heads would be a good idea? What do you recommend for a head cut?
Thanks

measure your squish on your engine and follow the specs i gave you in the first reply, that will wake it up some.

 

[woodyy69]

Right on thanks for the advice! Gotta do somethin to it since I got it all apart waiting for parts