mtb_tuli
Active Member
Hi,
Just sorting out all parts, that I will need to re-build my heads to the engine. I will give away my SD1 heads for skimming, but not really sure, what to skim to slightly increase CR. I plan to use tin type gaskets again.
At the moment I plan to reduce by 0,6 mm (20 thou inch is 0,508 mm) which should increase from 9,25 to around 10 :1. If anyone has experienced figures, it would help.
Then, for the older heads there are no "pre-stretch" bolts used, where you always must use new head studs.
Obviously, the old heads (no SD1) which I removed, were off some time ago, because all studs had no rust and were mounted with copper grease. The lower 4 ones were tighten like hell....
I´m not sure, I have read somewhere (manual ?), that you could use the studs 3-4 times, but i.e. RPI says, never ever use the old studs (ok, they sell new set for over 100 ).
Any help appreciated.
Just sorting out all parts, that I will need to re-build my heads to the engine. I will give away my SD1 heads for skimming, but not really sure, what to skim to slightly increase CR. I plan to use tin type gaskets again.
At the moment I plan to reduce by 0,6 mm (20 thou inch is 0,508 mm) which should increase from 9,25 to around 10 :1. If anyone has experienced figures, it would help.
Then, for the older heads there are no "pre-stretch" bolts used, where you always must use new head studs.
Obviously, the old heads (no SD1) which I removed, were off some time ago, because all studs had no rust and were mounted with copper grease. The lower 4 ones were tighten like hell....
I´m not sure, I have read somewhere (manual ?), that you could use the studs 3-4 times, but i.e. RPI says, never ever use the old studs (ok, they sell new set for over 100 ).
Any help appreciated.