ok guys what's up? i got a question for you... 13:1 C/R is 13:1 C/R right? here's why i ask i'm running endyn RW 84.5mm 12.21-12.98:1 C/R (i'll post the part # when i get home) i don't think they are the 13.09-13.99:1 's C/R (when i ordered them i just said h/c) back to the question does a 13:1 C/R JE piston make any more power than a endyn 13:1 C/R piston (i know most of you hate fakdyn, *if there was two race motors exact mods*) BTW what's up with the old crower cams 63403's (12.5 lift) and the new 63403's (11.97 lift)??? anybody know why they changed it? anyone know when the skunk drag cams (stage 3) are coming out or have any spec's thanks


[Modified by dohcsideSi, 7:12 PM 1/17/2002]

 

I dunno if its me but I can't understand you the skunk stage 3 cams should be out within a month or 2 (not sure exactly - why don't you call 'em 510-781-0538) you might wanna edit the rest of you question so others can easily understand what you are asking

 

I agree.....don't understand what he is asking.

 

if your asking if compression can change no and yes if you got 13.1.1 endyn pistons they will be 13.1 for the application you got it for, the only way the compression can raise is by the combustion chamber like the b18c1 has a 42.6cc combustion chamber wich will make .2 more compression than the same pistons in the same block with a b16a head. The reason is the gsr's combustion chamber is smaller. By the way the b16a has a 42.7cc com chamber.

 

sorry for the confusion let me make it a little clearer. i'm debating whether or not to sell my Endyn pistons and buy JE's. do you think there is any performance difference (i know the endyn pistons are heavier)? remember this is a fully built motor. thanks hope that helps
p.s. i have a gsr head that's figured into the 13:1 c/r


[Modified by dohcsideSi, 8:17 PM 1/17/2002]

 

I don't think your motor will know the difference between the Endyns and JEs.
Remember also, the piston isn't the only thing that controls your compression ratio. Things like deck height, head gasket thickness, etc. must be factored into the equation. 13-1 piston might really give you a compression ratio of 12-1 or 13.5-1.

 

the reason they give different compression numbers is to compensate for different deck height and/or different combustion chamber.

 

these are the specs that someone has found....not sure if its correct

Skunk2 cams

Stage I

INTAKE lift- 11.58 mm, duration 252 @ 1mm
EXHAUST lift - 10.9 mm, duration 249 @ 1mm

Stage II
INTAKE lift- 12.07 mm, duration 265 @ 1mm
EXHAUST lift - 11.6 mm, duration 256 @ 1mm

Stage III

INTAKE lift- 12.7 mm, duration 273 @ 1mm
EXHAUST lift - 11.5 mm, duration 273 @ 1mm

 

i know the c/r i was wondering about everyone saying that the endyn pistons don't perform (like only pushing 220 whp and je 's w/ the same setup pushing 240whp???). and i should just get je's. was wondering what if any diff could there poss be (besides wieght) thanks

 

To answer as asked...

Compression ratios being the same, I'd bet that if you installed the JE's and tuned the motor for them(which might be a pain, esp on the lower grades of race/higher grades pump gas), then swaped the the RW pistons in, all things being the same, you'd run very rich and maybe make less power... Now if you retuned the motor for the RW's taking into account that they would probably "like" less timing and fuel... who knows, you might just be happy... esp of how tollerant the tuning window might be...

Now in plain english... in short, try it yourself, cause this subject has been beat to death on the R and Forced Induction boards and the result is always the same... LOADS-OF-BULL FROM BOTH SIDES and few same for same dyno/time slips to back up the opinions.