should one machine just the gasket surface, or take some out of the squish to and just make the dome smaller. how much can one go before needing fuel better than premium

95 xplorer intake port and transfers have had edges sharpened and boost ports widened. exaust port has been widened by 5mm and raised 2 mm. stock pipe and boyeson power reeds. will be getting a psi pipe and a vforce reed.

 

I know if you shave the head .020 " you don't need to run race fuel , just high octane 92+ premium .

Jim

 

well i am a machinists by trade, so i did it myself. If you told a performance shop to cut it .020 then they might have kept the squish area the same. Or did they reduce the squish as well that's what i need to know thanks

 

it will reduce squish, mine is cut the same as jimmys I run 93, last conversation I had with rck ritter he said theres more to it then cutting the head 0.020 to get 12 to 1 but that sort of confused me. exhaust widened 5mm total or per side? did you touch the intake any aside from the boost ports.

 

well if he said there was more to it than maybe i should machine the squish area the same .020. I've got to re check the sompression now that it is broken in. the exhaust is widened 5mm overall. which takes it from 60% to 65 % width compared to the bore. which is 85 mm (max wiseco size) they say you can only get away with 70 % on an exhaust port that has no bridge to support the rings. me and my brother were switching of between it and my cr 250. It was getting towards the end of the ride so it was getting low on gas. he is telling me that it is detonating after long runs wide open. so i get on it and ya it won't hardly run so i switched it to res and it came back. But i didn't hear anything other than running out of gas. he has simialar problems on his 2000 scrambler 4x4 ( 430 big bore, 38 mm roundslide carb fmf gnarly pipe) when he climbs sand hills especially when less than half a tank. It will stall out like it seized then just fires right back up again. Do you ever have these problems

 

I have not had those types of issues. I did however not chamfer the ports correct(imo Ive been told I did them fine and had an exhaust ring clipping which would slow the motor down a lot in the form of a bog, I could power past it, for a while lol.

Or fuel starvation start at the tank and work all the way back. 60% of bore is what I was taught to be the limit on this motor or the rings would not return correctly, are you sure they are not clipping the exhaust from not returning all the way? So you did not drop or work the intake floors/transfer chambers at all I take it? widening the boost ports adds a lot to low end but truthfully not much in terms of actual power when shooting hills etc. going just wide does not address proper timing etc.


Do this for the head, max squish for pump gas is 0.055(relatively ive seen them rn tighter)

 

The freakin fuel pickup is at the front of these tanks (way to go polaris) I had the same trouble with running out of gas - once it got down to a 1/2 tank, off the line drag racing it would be lean, and running away, in the shut down area. So I built a 2 gal aluminum fuel tank. I put 2 gallons in it and problem is solved. Plus I shaved 16 lbs by not having to have the tank full all the time.

 

ya i was aware of that i was thinking of trying to put on at the back of the tank. i'm not sure if i could get it to seal though

 

well i'm sure the rings are okay. the bottem end power is fine. even with a stock pipe. i'm going to put a psi pipe on it. have to build a bracket to mount the scrambler style sileincer. then i have got a vforce reed coming and then i'm thinking obout a 38mm tmx.

 

Go with a PWK from RCR or HPD it will be worth it in the long run.


149psi on the compression gauge is the max for a premium pump gas see what you get. theres lots of power in these jugs.