valvesprings

[TurboTR]

I'm having a problem with the rpm just flatlining at exactly 6770 at wot, both at the track and on the chassis dyno recently. Interesting So it might be springs I guess. Or? I have a 224 solid roller, Comp extreme street profile. The springs are unknown brand from Competition Products. 1.5" dia and spec at about 220 lbs seat, 530 or so over the nose. I think we need to go with a name brand 1.55" dia, something like 270+ seat, 5-6xx open. Anyone else run into this??

BTW IME 1.5" springs don't fit within the dimensions of spacered stock valvecovers without some extra meat added externally

Also changing cams to a 242 extreme street profile, the 224 is too small (and too advanced) for the intended rev range down the track. Car comes up awesome though, a great little street race type setup IMO. Basically it needs to go from ~ 6200 rpm to ~ 7200 rpm max. On the dyno recently it made peak hp at a lowly 5500 rpm (715 rwhp with some nawzz assist). I need that peak up over 6000 rpm. And of course it goes without saying, alot higher too

TIA!

TurboTR

 

[TurboCrazy]

Are you interested in selling the 224 cam? If so, e-mail me privately.

Thanks, Brandon

 

[EightSecV6]

If it is turbocharged you are way light on the open pres for a solid roller

 

[TurboTR]

Yes I'd be interested in selling the cam. The lobes were bead blasted per Ruggles and other's recs. It only has about < 1500 miles on it. It's been modded for use with the Duttweiler style cam retention bronze plate

Yes it's turbocharged, 30 psi boost on it What would you think the springs rates oughta be for it? TIA.

TurboTR

 

[TurboTR]

Anyone have some 1.55" spring PN we might use here? Currently we have a 1.75 installed height, and we need like 260-290 range seat pressure along with lift clrnc for .627" + 0.060" margin... Not asking much are we? ;-) We may be able to get a 1.80 or 1.85 installed height with a different retainer. Anyone??

TurboTR

 

[Chuck Leeper]

Springz??

Todd, I have the CC catalog here. I find the following:
Pt# 9990 has 1.550" OD/ .724" ID, the application chart shows seat press. at 260# w/ inst. hgt @ 1.800. At 1.150" the open press. is 671#.They are moly disulfide coated. It is a double spring.
coil bind is at 1.090".
Titanium retainers are: 732 for std wt and #721 for litewt. The cups are 4700, 4781,4782.

HTH!

back under my inj bench...

 

[TurboCrazy]

Hmmm, that almost sounds like mission impossible!

 

[TurboTR]

Yeah it's tough with prod style setups Not much valve length there. I think Chuck has a winner there. I called Comp and they mentioned a +0.050" 10 deg keeper too. So it looks like we can get what we need I think, a 1.80" installed height, about 260 lbs seat pressure, about 660 lbs open pressure with .627" lift, and still have 0.080" coilbind margin

TurboTR

 

[KendallF]

I feel your pain, Todd. Did you remember to subtract the spring cups from your installed height? I think we are going to send back the springs I bought for my S2 heads, but I'll have an easier time finding replacements. The installed height for them will wind up around 2.00" but with .060" spring cups you get 1.940" and that puts my seat pressure up to just over 300. I want a little less (260-275) so back they go...