upon a recent mid summer rebuild i completed using the same vitara pistons although this time in .020 over i removed my blockguard that i recently had installed in my block for the fact of the heat distortion and discoloration i found in the cylinder walls directly where the blockguard was placed.

i used a supertech blockguard at the time which i'm sure many of you know does not have sufficient size coolant ports like found in the golden eagle ones.

so my question is that, i'm planning a retune on 20 psi again out of a .57 trim turbo (previous tune before rebuild) and i was wondering how much WHP are stock SOHC y8 sleeves good for without a blockguard or should i reinstall a new blockguard using a golden eagle this time?

 

i would use the block guard at that psi level if i didnt have sleeves.
boring it didnt help at all. you made it thinner(you know that though, you seem smart)
if your going to get serious. just do a sleeved block now. youl regret not sleeving it when your driving it and you want more boost and more scaryness...i regret not sleeving mine.
20lbs is pushing it......just do it and see what happens. then rebuild...again..

 

SpeedFactory got well over 500whp on stock sleeves.

 

thanks man, hey i got one other question for you. when i got it bored i told the machine shop that i needed .0035" ptw clearance, but i'm not so sure they gave me what i ordered and i have been experiencing oil pressure problems that i think is due to excessive heat which is thinning my oil viscosity out.

when i run the car in WOT i lose oil pressure below the 50psi minimum at 3k. it drops to 35psi, but then i run the car easy for say 10 mins oil pressure comes back to 40-45psi at 3k. i never experienced any oil pressure problems while using the std bore pistons.

this is why i think it may have to do with too tight ptw clearance, i talked it over with a different machine shop today and they said it's very possible

 

weird. in wot it should go up.
did you put a new oil pump on it when you rebuilt it?
did you gap your piston rings?
are you getting any smoke out the tail pipe.
i had ethanol hydrolocked in all the cylnders manytimes (had to keep changing the oil. injectors kept sticking) so i had loads of smoke and poor idle and no oil pressure.)
i put new piston rings in and wala. like brand new.
worse case senario for you is take the head off and check the pistons now. see if they wiggle. they should be tight. check with vitara though. im a Bseries dude. but i heard vitara does some weird stuff like create a normal knocking until they break in.

 

no smoke at all except for the rich(black) smoke at wot, no blue what so ever and no white either

i do plan to take the head off soon since i've decided to throw another blockguard in.

also with the cold weather approaching here in PA, i also thought about just throwing some new bearings in, this time i'm going back to regular acl's instead of the race series. also thought of new rings while im at it.

lol it's weird how the oil pressure dies down with heat (according to my mechanical gauge anyhow) but after allowing some cool down time, it restores where it needs to be.

oh well we will see i guess, not experiencing any breakdowns yet and engine has passed the 4000 mile mark with no problems thus far , thanks for your advice man, it will be very helpful to me