i have a gsr block with a b16a head(poor mans r) withiut getting into the mods i have i was wondering the compression i would be running. i have wiesco forged pistons it has a compression height of 1.185 i used the calculator but it seemed to low it was listed as 12.5: 1 but im starting to think that it wont be that high has anyone experenced or used these pistons to know the approx. compression i would have cause the whole reason i bought them was to raise the compression from the stock jdm b18c ones would they??? how much more?

 

Is this the compression calculator you used?

http://www.c-speedracing.com/h...c.php

 

yeah thats the one but like i said it said only 11.1 but im not sure what the out of the hole height i should use?? the b16a or b18c cause i have the b16a head i dont know if that would change things around a bit??? but if i use the b18c it says compression would be 10.8 thats really low even the website says 12.25 -11.8 ??

 

also would the piston to deck height be diffrent cause im using aftermarket pistons so wouldn't the negative value be diffrent from stock values

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civic99b16a &raquo;</TD></TR><TR><TD CLASS="quote">i have a gsr block with a b16a head(poor mans r) withiut getting into the mods i have i was wondering the compression i would be running. i have wiesco forged pistons it has a compression height of 1.185 i used the calculator but it seemed to low it was listed as 12.5: 1 but im starting to think that it wont be that high has anyone experenced or used these pistons to know the approx. compression i would have cause the whole reason i bought them was to raise the compression from the stock jdm b18c ones would they??? how much more?</TD></TR></TABLE>

Ok well if you're using Wiesco pistons for a GSR block and they're rated at a compression level of 12.5:1, it's assuming that a stock 3 layer head gasket is being used and that a GSR head is being used and that the block hasn't been decked or the head milled. The B16 head has a larger combustion chamber than the GSR head (1.1cc) does so it will naturally drop the compression level below 12.5:1. Using that compression calculator to roughly figure out where you'd be at with those pistons by simply changing the head and assuming you were starting with a 12.5:1 comp ratio, it would drop your comp ratio to about 11.4:1.

 

do you think that should be good enough to make some good power ?? i know that 11.4 or whatever it may be is still pretty high but do you think i should mill the head a bit to raise it a little more its not too much to do but i know that milling the head throws the cam gears off a bit what would you do? i have every bolt-on possible plus stage 2 cams upgraded vlave train ect... you think i should be making a good amount of power?? and is it worth to mill the head i also heard i could take a layer off the stock gasket but to me that seems unsafe and its all rivited toghter i woulnt ant to mess up the gasket

 

I think that at 11.4:1 you should be making good power as that's a pretty substantial ratio for the street. If you wanted to raise the comp a little more I would go with a thinner head gasket like Cometic, or something. If you went with a 2 layer gasket you'd be at 11.6:1 and if it was a single layer you'd be at 11.8:1. Again, more than adequate for your street motor.