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ARV90SC
02-23-2005, 03:15 PM
ok so i got a 94 blower(stock 90 or 12% od, dont know yet), upgraded injectors, MAF, etc. i was wondering which pistons i should go with and if i should drop the compression on them because of the more charge in the cylinders? im going to be running NOS too, someone told me to go with a 94 set, but ....i dunno, i dont want to be blowing any headgaskets here either any help will be much apreciated. thanks

arv

joshbea6
02-23-2005, 03:33 PM
I've got a set of Wiseco forged pistons.

I got them from Tom at http://www.supersixmotorsports.com/

They look beautiful, and hopefully I will have them back to me with the engine soon.

-Josh

T-bird4vr
02-23-2005, 05:05 PM
I was always told if you are going to squirt juice then you need forged, otherwise run 94-95's.

BlackbirdSC
02-23-2005, 05:28 PM
If you're going to run 10%+ OD and NOx, you'll make more power dropping the compression. 94-95 pistons raised CR to 8.4 from the earlier 8.2. And the 94-95 set has the option of floating the pins which you can't do unless you have 94-95 rods to match.

If I were you, I'd get a set of Eagle or Scat I beam 351W rods and a custom set of pistons from JE, Ross or Arias. Make sure they know you're intended usage and rpm range. They'll probably assume you're going to wring it's neck and build you pistons to run 8000 rpm. It takes a different shape piston for 6000 rpm use than it does for 8000 rpm. So be specific and accurate when calling them.

Aim for 7.5-7.8 CR and turn up the boost and squeeze. You're going to have effective CR in the 16 range on nitrous no matter what. With the slightly lower static CR, the combustion chamber will be a little larger. With a blown & NOx engine, 100% cylinder fill isn't much of an issue. Assuming the blower and NOx setup can handle the airflow. Much below 7.5 and off boost performance will suffer too much.

ThunderRoad
02-23-2005, 07:39 PM
:eek: A 50-75 SHOT OF NITROUS DRY ...YOUR SAYING THAT THE VPISTONS ARE NOT GOING TO HOLD UP FOR THAT?????????????? :confused:

ARV90SC
02-26-2005, 12:20 AM
wow, some good info, now if i was running it as a daily driver some days with the 7.8CR will i still be in a good power range without the NOS? by the way im running the 38lbs injectors, and a 76mm C&L maf, 150 feul pump to go with the 94Blower and the 10%od off a 90