When I have the money and the resources I will be running a 12:5:1 ratio....to keep it from piston slapping like a pimp to his 2 dollar whore. I will raise the deck lid....ballpark what kind of cost will this run me?





Performance: Stuff that makes my car run better or go faster

Looks: Stock because looks doesnt make my car go faster or run better

Weight Reduction: CF Hood, No A/C or Powersteering Accessories, No rear interior

To my knowledge this isn't needed. I thought the 12.5:1 C.R. pistons were made not to slap on stock head with stock gasket. If you start milling the head then maybe... but I thought they'd run fine. Where did you hear that they wouldn't?



15.9 @ 86.7mph

Injen CAI, 55mm TB, P&P Intake, Crower Cams, Hooker Header, ERT/Catco Cat, GS-T Muffler, AFX UDP, Crane Ign Amp, S-AFC

there a larger piston all together....i know alot of ccars in order to run 12:5:1 compression there racing the deck lid



Performance: Stuff that makes my car run better or go faster

Looks: Stock because looks doesnt make my car go faster or run better

Weight Reduction: CF Hood, No A/C or Powersteering Accessories, No rear interior

If you buy the 12.5:1 kit from howell they are designed to work with a stock block and head.



________________________________________________________________________________________
Car Sold


http://hometown.aol.com/ohshootuhh/
www.Fast420A.com

I dont trust Howell....I would rather just buy everything myself then worry if someone like howell will send me everything at once



Performance: Stuff that makes my car run better or go faster

Looks: Stock because looks doesnt make my car go faster or run better

Weight Reduction: CF Hood, No A/C or Powersteering Accessories, No rear interior

then if you want to buy everything yourself you have to do the figures on custom pistons so they will work without hitting the head and with deep enough pockets for .500 inches of valve lift. They have already done this for you. Either way there are a few companies that carry pistons for the 420A in high compression, they should have done some research so any of the 420A pistons should be fine.





________________________________________________________________________________________
Car Sold


http://hometown.aol.com/ohshootuhh/
www.Fast420A.com

www.raceeng.com talk to those guys, they seem to know there stuff!

I had je 12.5:1 pistons in my sebring long time ago. Without thicker head gasket (or raising the deck) i was putting ~15:1 compression. It WILL work but i wouldnt recommend....

Oh those were the fun days.


_________________
Vinnie Lima
vinnie.lima@jvllogistics.com
AIM: Kiku888
1997 Chrysler Sebring "Silver XTC"
I4 420a w/ HRC Stage 2.45 w/ FMIC
14.7@97 mph@6psi
Proud member of the
ASOG BoOsT JuNkIe Crew

Didn't you have a milled head also Vinny?

If you have the head ported and polished then that is going to lower the overall compression ratio since material is removed from the head so there is more airspace in the combusion chamber at that point so that may be something that you want to have done before 12.5:1 pistons are put in.





________________________________________________________________________________________
Car Sold


http://hometown.aol.com/ohshootuhh/
www.Fast420A.com

Hey Vinnie, who did the calculations on the compression ratio for you on the head? I had the machine show I'm using clean up and get the head ready with a minimal mill and they checked it giving me an estimate of .015" milled off. I thought you had more taken off than that.

Kyle, do you remember the volume in a stock cylinder head?



15.9 @ 86.7mph

Injen CAI, 55mm TB, P&P Intake, Crower Cams, Hooker Header, ERT/Catco Cat, GS-T Muffler, AFX UDP, Crane Ign Amp, S-AFC

If my calculations are correct,

1996cc engine divided bt 4, 1 cylinder is 499cc divided by 9.6 (compression ratio) and you have 51.99cc for the combustion chamber. Other than that, I am not 100%.

Someone needs to cc the head to see how much volume there is up to the HG. and then we'd know what the head has volume wise and what the block has volume wise with the piston at TDC.






________________________________________________________________________________________
Car Sold


http://hometown.aol.com/ohshootuhh/
www.Fast420A.com

Hmm... maybe a rough calculation I can do when I get it apart... If I can find those cyringes again...



15.9 @ 86.7mph

Injen CAI, 55mm TB, P&P Intake, Crower Cams, Hooker Header, ERT/Catco Cat, GS-T Muffler, AFX UDP, Crane Ign Amp, S-AFC