surplus 6
XS400 Enthusiast
were there any markets that had lower compression pistons fitted (for low quality fuel etc) as I may need some if my plan comes together 
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lower compression pistons
- Thread starter surplus 6
- Start date
you going Turbo?
get them machined or open the squish area up in the head
get them machined or open the squish area up in the head
surplus 6
XS400 Enthusiast
thanks for that eric123, may go that route if the turbo ever lands in my possession, that reminds me, must check compressor map
if your going turbo I wouldn't recommend thicker gasket, you would need a copper one for turbo any way or else it'll blow the gasket out.
redratbike
XS400 Addict
use a "wills ring" a groove machined into the mating surfaces to stop blow by under force induction with a stainless ring of wire
The black rings are the Wills Rings,they are gas filled tubes which are located in a special groove thats milled into the face of the alloy head
sounds expensive
surplus 6
XS400 Enthusiast
looking into it, had thought of the xj 650 turbo as it's a small unit, but also looking at small car ones. had thought about the smart car, it's 600cc turbo but the turbo and manifold are made as one so looking else where at the moment. still at the research stage yet
surplus 6
XS400 Enthusiast
hope to utilise used stuff from breakers yards, or evil bay
surplus 6
XS400 Enthusiast
I have heard of these, a few of the members of another forum I modderate on use turbo's or superchargers. never seen a photo of them though, many thanks for that.
there was an xs400 turbo used in straight line racing here in the UK. I tried to contact the owner to no avail
surplus 6
XS400 Enthusiast
thicker base gasket wouldn't see any turbo pressure?
the cylinder will have more air fuel mix and will burn more efficently. this increases compression considerably/creates more heat. depending on the pressure set, you could blow the pistons through the engine case (now we have waste gates to counter that)
surplus 6
XS400 Enthusiast
yes it does create more pressure thus more heat, by forcing more air/fuel (can be upto 40% more) into the cylinder, but that is above the piston and not at the bottom of the cylinder where the base gasket sits, so thicker base gasket could be an option if there are no other options, that is what I was saying
yes it does create more pressure thus more heat, by forcing more air/fuel (can be upto 40% more) into the cylinder, but that is above the piston and not at the bottom of the cylinder where the base gasket sits, so thicker base gasket could be an option if there are no other options, that is what I was saying
ah yes, I read cyl head gasket in me head and really didn't read your post properly, my bad
redratbike
XS400 Addict
thick base gasket raises barrel which means a bigger squish area = lower compression
( PISTONS WONT REACH TOP OF BARRELL )..easiest ,cheapest way of lowering compression ..you can either have one lazer cut or use 2 -3 base gaskets ..think cometic would be the people to go to in the USA
http://www.cometic.com/custom.aspx
( PISTONS WONT REACH TOP OF BARRELL )..easiest ,cheapest way of lowering compression ..you can either have one lazer cut or use 2 -3 base gaskets ..think cometic would be the people to go to in the USA
http://www.cometic.com/custom.aspx
surplus 6
XS400 Enthusiast
Anywhere in uk do them?
you need to update your location, then we are not recommending suppliers the other side of the world
checkout halffastchicago.com there is a guy on there that is doin a turbo CB750. it looks pretty small, i think its a garrett GT17. you cant look at it tho. gotta live in the area. check out the xs650 turbo on xs650.com that might help
check out the xs650 turbo on xs650.com that might helpsurplus 6
XS400 Enthusiast
"there was an xs400 turbo used in straight line racing here in the UK. I tried to contact the owner to no avail"
I may have a contact for the owner/builder. someone on britchop just gave me the nod
I may have a contact for the owner/builder. someone on britchop just gave me the nod
