i thought i bought wiseco 9.1 but when i got them i checked my wiseco kit-number on their webbsite and then i got 8.3-8.6
my kit number is k541m815
is it much difference between 9.1 and 8,3?
i have a b16a1 and planing to hit 350whp with a garrett 57trim, itr cams, ramhorn and eagle rods

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<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by anton_ &raquo;</TD></TR><TR><TD CLASS="quote">
my kit number is k541m815</TD></TR></TABLE>

That part # is calculated for a GSR Motor, 81.5mm bore and 8.6 - 8.9 Comp Ratio. In a GSR...

You should have ordered, K542M815, which would have been 8.8 - 9.0 Comp in your B16.

 

ok?
but what do i get with the pistons that i hve now?

 

I dont know the intricate differences of each piston...you will have to do some searching and find an online compression calculator.

 

you'll get about 7.7-8.2:1 C/R

 

but how do i messure Piston Dome Displacement?

 

http://c-speedracing.com/howto...c.php

call wiseco or go to wiseco website

-12cc dish pistons http://wiseco.com/PDFs/Catalog...a.pdf

 

7.5-1 not good.

 

This is why you buy parts from people who know how to recommend what you should buy and what you shouldnt instead of just buying from some internet jockey operating out of his grandmother's basemap who only wants to take your money

If you need any help getting this resolved, let me know...but since everything is installed just rock it and turn up the boost

 

i accualy bought from i guy that i though was wery good, he is very recomended, but all can make misstakes,
dont think i want to run that low,

thanks

 

i would run that compression. don't let the "too low" compression scare you. you can run more boost/power and still be very safe even on 91oct fuel.

higher compression just makes it a little trickier to tune....i highly doubt you will notice/feel any difference between 8:1 to 9:1

i had the same wiseco 8.XX:1 pistons and i switched to JE pistons and shaved the head enough to run about 9.5:1cr......the difference was hardly noticable....

 

i checked the comp caculator, and if i take away one layer if the headgasket and milled the head down maybe i should get 8.0

 

the piston comes out of the cylinder by 0,25mm thats about 0,01" if i put the head on without a gasket the piston hit the head a little bit. i can pull the engine around by hand, so it is very little.
is it somethin to wory about?

 

if the pistons stick out passed the deck of the block the compression will be much higher than what you originally calculated.

sounds like your machine shop machined the deck of the block alot.......

 

but can i run rhe engine like that?

 

you might be able to......have it properly measured at the machine shop.

 

Regardless of that the compression is in your situation, yes you should be able to hit 350 whp with your set up... you will probably be hitting those kind of number anywhere between 16-19 PSI and yes 93 pump gas will be ok as long as your tuner know what hes doing.... Good Luck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by anton_ &raquo;</TD></TR><TR><TD CLASS="quote">but can i run rhe engine like that?</TD></TR></TABLE>

I wouldn't run less than .025" piston to head.If your up .010" than i would run the stock hg unaltered.Your real choices are change the pistons to a true 9:1 or run what you have.Like has already been said the low ratio isn't that bad.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by xenocron &raquo;</TD></TR><TR><TD CLASS="quote">... instead of just buying from some internet jockey operating out of his grandmother's <U>basemap </U>who only wants to take your money </TD></TR></TABLE>

Someone's got tuning on the brain...i just saw that and thought it was funny.

 

Yep...Freudian Slip!!!

 

sounds like alot of hassle, since there already installed i would just go for it nothing wrong with low compression supplimented with lots of boost.

 

just about all the shelf pistons stick out of the hole on b16s. do not take a layer out of the gasket the pistons will hit the head if the piston to wall is real loose you might want to put a thicker gasket on it. allso make shure the gasket has 0 overhang into the bores. or you can just take the motor back apart and take the pistons to your machine shop and tell them to take 25 of the tops