Two Base Gaskets?

[rmxtwofitty]

I own a 1991 rmx 250
Mods:
1994 cylinder and head
FMF pipe & silencer
mo better porting
overbore to 265
and I recently bought a nos head off e-bay and had it milled for race gas and bolted it on. I have jetted down for the race gas but now I have heard that people are milling their heads, and then running two base gaskets to change the port timing, but with the milled head it keeps them close to the original compression.
q: Has any one tried this, did you like it or not?
With the lowered compression would I mix my race gas with pump?
And any idea on what I would need to change my jetting to.

Thanks

 

[Studboy]

The change in port timing will give you more topend in exchange for bottom end power. It is a tradeoff. The milled head (depending on how much was taken off) should put you close to your original compression.

If you are looking to save money and just boost octane, I would run 50/50 C12/Premium pump.
I'm not sure how it would affect your jetting. Your best bet is to get it running then do some plug chops for the main jet and just do the ride and feel method for the other circuits.
Do you know how to read the plug correctly? (Not just by insulator tip color).

 

[Studboy]

q: means question, right? :nener:

 

[buffmaster]

Studboy, if the correct way to read a plug isn't by the ins. tip color, then how do you do it? That's what I've gone off of in the past.

 

[Studboy]

Check out this thread:
http://www.dirtrider.net/forums3/showthread.php?t=92818

I was doing it wrong before I read this thread.

 

[buffmaster]

Yeah, so was I. Thanks a lot SB.