I have a '97 Warrior with a FST 446 kit. The first time I took it out with the 446, the head gasket blew out the right side. It still ran, and ran good, but when I hit the gas hard it blew exhaust by the gasket. The 446 kit came with a "paper" head gasket reinforced with metal. I replaced the blown one with a full metal gasket and after about an hour this gasket blew out the front. FST told me I didnt tighten the head bolts correctly. I torqed all the head bolts down to specs and tightened them down in a criss-cross pattern 2 ft.lbs at a time! I had the cylinder decked when the engine was apart, but not the head. Do I need to get the head decked now to match the cylinder? If not, what else could it be? I didnt have any problems with this before the 446.

 

What is the stated compression of the 446 kit? What octane fuel are you running?

 

I'll have to do some research and find out the compression. I run 93 octane.

 

I know it's been a while, but I finally got it running right - so far. I still can't find the stated compression of the 446. FST told me I could still run 93 octane fuel, so I guess the comprssion is not too high. I had to get the head resurfaced and they opened up the combustion chamber just a little to relieve a little compression. The surface of the head had a few little nics on it where the gasket seals. I hope this will keep it from blowing again. Its OK right now.

 

Good going. Sounds like you solved your problem. Ride safe and have fun!!!

 

Static compression for the 446cc kit is around 11:1. Now it's maybe a little less.

I'd make sure and get the proper gasket bore as well. I had cometic make a custom one for my app. and it was really cheap and can be reused without having to re torque.
Were the nicks in the head on the exhaust side or where the gasket blow out?

 

Yeah, I ordered another head gasket from FST specifically for the 446. The nicks were on the right hand side of the combustion chamber, right where the gasket was supposed to seal. The nicks were really small, so I'm not sure if they were the problem. The machinist that resurfaced the head was at lunch when I picked it up, so I didn't get a chance to talk to him to see if the head was actually warped or not. The first time it blew out, it blew out the right side. The second time it blew was in the front on the exhaust side. I realize I may have lost a little compression and maybe a little power, but at this point I just want it to run right so I can ride!

 

well if they had to plane the head or machine the nicks out of it then I would guess that you actually went up in compression.
Torque is like 29 lbs?

 

Well that's true. He didn't shave much. I think he went took off about 0.003". Maybe for the compression added there and the compression taken away from the combustion chamber maybe it equaled itself out? I've always been told you can't shave the head of a Warrior too much because it will throw off the timing somehow or another. I haven't figured out how, though.