921's or PRC Duals??

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Mar 15, 2008 | 01:45 AM

bayer-z28

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From: N. Falmouth MA

921's or PRC Duals??

Which ones??

These will be going with a 640 lift cam @ 228 duration.. (PG TQR Cam).. What's the rate on the PRC Springs?

Comp 921’s: rated for up to .650 lift

O.D: 1.300
I.D: .870 (outer spring)
I.D: .655 (inner spring)
135 LBS @ 1.770
400 LBS @ 1.220
COIL BIND @ 1.040
MAX LIFT .650

PRC Dual Spring Kit: good for up to .660 lift

seat : 140lbs
open: 390lbs
install : 1.800
coil bind: 1.07
1.290 O.D.
max lift : .660
matl : super pure chrome silicone

Mar 15, 2008 | 11:59 AM

bayer-z28

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From: N. Falmouth MA

Bump...

Need some help here..

Mar 15, 2008 | 12:10 PM

magius231

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From: Winston Salem, NC

personally I would do PRC's, but call Texas speed and make sure you aren't too close to the rating. IMO you will get better support with PRC's in case anything isn't right.

Mar 15, 2008 | 12:30 PM

bayer-z28

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From: N. Falmouth MA

I'm getting the cam from TR...

Speaking of which, Patrick G: What springs do you recommend with your TQR cam? (Not sure if he's lurking or not)

Mar 15, 2008 | 12:49 PM

Bill Bowling

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I would go with the PRC's.

Mar 16, 2008 | 12:15 AM

bayer-z28

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From: N. Falmouth MA

^I'm starting to think the PRC's as well... The 921's are good for .650 lift, the PRC's are good for .660 lift.. That'll give me a little bit more room.

The only reason I ask is I don't hear a lot of people SWEARING by them, but on that note I haven't heard ANYTHING about failures with them.