Detonation risk

[damann33]

Well as some know, I bought a 55mm hc piston from akunar which will be sitting 1.7mm down in the cylinder. I was just wondering if I always run good gas, 98 99 octain with all those fuel addictives, along with getting the piston dome ceramic coated, will detonation occur? What problems can occur running the piston down in the bore. I recently switched from a tb 300 cam to a milder cam, to increase compression. Thanks

 

[Dave.B]

u ride a pitbike

 

[ducar.r.spec]

deck the top of ur barrel

 

[damann33]

that would effect my cam chain length, but it didi seem like a simple soulution for a sec

 

[ducar.r.spec]

u only need to go down a little over 1 mm
so u tension that back out

 

[damann33]

well I would need to remove two link in order to rejoin the chain which would mean I would needa get the cylinder, and head down around 8mm to gain stock tension

 

[ducar.r.spec]

tension it with the cam chain tensioner
dont break links lol

 

[damann33]

well the cam chain adjuster is automatic, I can loosen the bolt to give me more slack, then it will tighten to regain stock tension. The thing is that the chain will be too long still, meaning the cams timming will retard. My plan of of now and probably wont change due to the conditions with modding this engine, I will use the stock gaskets, stock cylinder and then just install the hc piston with the 8.5mm dome, and let it sit 1.7mm in the cylinder. If you think about it the stock piston has no dome, and is flush. I have an 8.5mm dome with valve refiefs grinded into it, and even with it down in the bore ill have more compression then stock which is all that matters. I will probably get the piston dome coated with ceramic just for some extra protection, and ill see what my piston to valve clearance will be. I think I may be able to run a thinner head gasket, which shouldnt effect cam timming to much, will provide me with more compression, but then ill have to cut out the valve refiefs some more which will make me loose compression, and the cam timming will be effected, so maybe not.