ok guys too much stuff floating around thats contradicting.....

I cannot find high compression pistons for th ld9, so now i'm going to pull off a head combo to raise the compression, or maybe lower depending on what makes most sense for me

I have two ideas..N/A, and boost....duh haha

anyway the N/A build would entail a 2.3 head swap-obvious-but nw the point is the 086 casting was said to have been too thin and brittle once you port it? but the other..umm crap I can't think of the number......blank....ill edit later, or i'm sure someone will post on it, but neway they flow fairly close and I have heard they are less prone to crack and I think there is another quad 4 dohc head isn't therre...o well if you guys feel like waisting your time to chime in I'm here to listen lol

also i'm totally undecided as of yet between N/A, mp45-I know, I know- or maybe trying to come up with a m65 intake that will work with my ld9, or turbo? pain in the ass .....
O yeah and the second style ld9 head....maybe bolt it on to give me a larger combustion chamber and also it flows much better than the first style ld9 on the exhaust side....ref the thread "head swap" where pat did about err four years ago(be easier if I just looked up the time stamps lol) did a head for zyaaa(who i pm'd earlier today for some info as well) as well as his own ---one was pre 99-zyaaa and one was post 99 his own

realistically you dont need to port an 086 head. it just needs smoothed and blended with a good valve job. its not really the porting them thats the issue though... its the fact that they crack between the valves/spark plug holes. nobody has ever really proven why this is but we speculate its due to bad design and or casting issues with a little poor aluminum mixed in LOL

i have heard that the "small" 086 casting seems to hold up better than the "large" casting (the numbers cast into the head are either small or large) but ive seen either one cracked.

IMO it'd be best to get a good 086 and then have it cryotreated for strength just to be safe. then just be sure you never overheat it!

as for the head differences it was the other way around... the older LD9 head flowed better on the exhaust versus the newer and the intake flowed better on the newer versus the older. but in the end they are basically the same. you can always smooth out the cathedral protrusions in the combustion chambers on the older head if you are worried about the intake flow.

if i were you i'd go n/a. and what do you mean you cant "find" pistons? just call up any of the piston manufacturers and they can make you whatever you want. wiseco, diamond, venoila, JE, CP, ross, etc. all make pistons for us.



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