CMF_gibson_racing
» CMF Member
hi all just woundering does anyboudy have measurments of a piston ring for a 1.3l i am mainly after gudgeon pin diameter and from top of piston to centre of the gudgeon pin
piston measurments
- Thread starter CMF_gibson_racing
- Start date
CMF_frank2
» CMF Memberthe pins are 18mm GB (interference fit to rod) and pin center to crown is 28mm
what you got planned ?
what you got planned ?
CMF_gibson_racing
» CMF MemberWell I was going to skim the head 2mm frank like you did two raise compression . But because my car is used for speedway the engine is close to nearly on the rev limiter all race so engine life is decreased if I did that. I could get the same effect with pistons from a motorcycle if found that Honda cbr900rr pistons will fit straight in no boring and the compression ratio is then 12.5.1 so that is what I was looking at so just needed to see if the Gudgeon pins would line up meaning the piston doesent exceed past the top of the bore
CMF_frank2
» CMF Memberbike pistons will have a raised crown tho surely ? (domed)
giving way more than 12.5:1
giving way more than 12.5:1
CMF_fred
» CMF Memberhay, its worth a look, very interesting.....
CMF_gibson_racing
» CMF Memberdepending on the bike most bike pistons are flat tops with the divits in the crown for the valves. but im not sure if the micra engines have dome or flat tops?
doese anybody have a na car out there with racing pistons in it with a high compression ratio or just normal compression?
would like to know what brand and were they came from and prices
"frank
bike pistons will have a raised crown tho surely ? (domed)
giving way more than 12.5:1"
possibly if it did do this you can compinsate with a high fuel rating e.g bp100 avgas , e85 to stop the engine from detonation and
doese anybody have a na car out there with racing pistons in it with a high compression ratio or just normal compression?
would like to know what brand and were they came from and prices
"frank
bike pistons will have a raised crown tho surely ? (domed)
giving way more than 12.5:1"
possibly if it did do this you can compinsate with a high fuel rating e.g bp100 avgas , e85 to stop the engine from detonation and
CMF_climberjoel
» CMF Membercg10 pistons are flat topped, and cg13 pistons are concave (oposite of domed), which is why as frank said cg10 pistons raise the comp ratio in a cg13.
maybe with the bike pistons you would have to cut in recesses for the valves? good luck with the project any way, definitely exciting! the only source i know for high comp pistons is Matt humphies as i said earlier.
p.s. why does it mater what you chose to change in terms of reliability? what i mean is, is it not the same effect on engine stress/longevity when you raise the comp ratio by milling the head as to raising it by different pistons?
p.p.s. if you raise comp ratio by getting domed pistons in a cg13de for example, does this result in slightly lower engine cc's?
maybe with the bike pistons you would have to cut in recesses for the valves? good luck with the project any way, definitely exciting! the only source i know for high comp pistons is Matt humphies as i said earlier.
p.s. why does it mater what you chose to change in terms of reliability? what i mean is, is it not the same effect on engine stress/longevity when you raise the comp ratio by milling the head as to raising it by different pistons?
p.p.s. if you raise comp ratio by getting domed pistons in a cg13de for example, does this result in slightly lower engine cc's?
CMF_frank2
» CMF Memberfitting the flat-top 1.0 pistons is a neater solution because you dont make the lower chain slack (which is what happens when you skim the head)
and all the cbr9 pics i came across had a domed crown with valve pockets
i,m personally detered by the interference fit wristpin tbh, the GA16 rod may be an option tho (same big-end dia i believe, and conventional bushed little-end and circlip fitment)
and its still the same swept volume (cc) whatever the C/R eh
and all the cbr9 pics i came across had a domed crown with valve pockets
i,m personally detered by the interference fit wristpin tbh, the GA16 rod may be an option tho (same big-end dia i believe, and conventional bushed little-end and circlip fitment)
and its still the same swept volume (cc) whatever the C/R eh
CMF_gibson_racing
» CMF MemberIf 1.0 pistons are neater fit anybody got a set or if you can get the same size equivellant in forged
