View Poll Results: greddy type s - how many springs ?
stock - two springs
40
34.48%
mod - single spring
76
65.52%
Voters: 116. You may not vote on this poll
poll: greddy type s - two stock springs or single spring mod
#3
BOV Max Piston Travel Spring Configuration Adjustment Screw Begins Opening (in/Hg) Fully Open (in/Hg) NOTES
Type-S
3/4" Both Springs (GReddy default) Minimum 21 25+ Will flutter unless the lower vacuum port is used...and even then sometimes. Loud whistle without the lower port, little whistle or whoosh when using the lower port depending on throttle change and air flow.
3/4" Large Spring Only Minimum 15 21 More quiet whistle or whoosh depending on shift conditions. May flutter slightly if conditions are absolutely perfect for it. No lower vacuum port connection needed or recommended. Our recommendation for Evos with minor adjustments (generally, 2-5 full turns).
11/16" Large Spring Only 2-3 turns from first contact 16 21 This setup most closely matches the default BOV characteristics and is our recommended configuration. Adjustments should be tuned to your taste/driving habits, but this works extremely well on our Evo with cams.
3/4" Small Spring Only Minimum 9 15 Absolutely no flutter under any circumstance. Whistle or whoosh depending on throttle changes/air flow. No lower vacuum port connection needed or recommended. Increased chance of opening under high boost. We do not recommend running the small spring.
1/2" Small Spring Only 7-8 turns from first contact 11 17 Absolutely no flutter under any circumstances. Whistles on every throttle change, no matter how light (which may be annoying). No apparent premature opening up to 21psi (max. we tested), however, it does open unnecessarily during highway driving conditions. No lower vacuum port connection needed or recommended.
Stock 5/16" Stock N/A 17 21 Quiet whoosh sound only, plastic sucks, can leak, it's "stock", no flutter, very small opening distance.
Type-S
3/4" Both Springs (GReddy default) Minimum 21 25+ Will flutter unless the lower vacuum port is used...and even then sometimes. Loud whistle without the lower port, little whistle or whoosh when using the lower port depending on throttle change and air flow.
3/4" Large Spring Only Minimum 15 21 More quiet whistle or whoosh depending on shift conditions. May flutter slightly if conditions are absolutely perfect for it. No lower vacuum port connection needed or recommended. Our recommendation for Evos with minor adjustments (generally, 2-5 full turns).
11/16" Large Spring Only 2-3 turns from first contact 16 21 This setup most closely matches the default BOV characteristics and is our recommended configuration. Adjustments should be tuned to your taste/driving habits, but this works extremely well on our Evo with cams.
3/4" Small Spring Only Minimum 9 15 Absolutely no flutter under any circumstance. Whistle or whoosh depending on throttle changes/air flow. No lower vacuum port connection needed or recommended. Increased chance of opening under high boost. We do not recommend running the small spring.
1/2" Small Spring Only 7-8 turns from first contact 11 17 Absolutely no flutter under any circumstances. Whistles on every throttle change, no matter how light (which may be annoying). No apparent premature opening up to 21psi (max. we tested), however, it does open unnecessarily during highway driving conditions. No lower vacuum port connection needed or recommended.
Stock 5/16" Stock N/A 17 21 Quiet whoosh sound only, plastic sucks, can leak, it's "stock", no flutter, very small opening distance.
Last edited by burningmoney97; Dec 15, 2004 at 11:08 PM.
#7
Evolved Member
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I run the single spring mod and don't have the spring screwed even half as far as burningmoney. I have HKS 264s and it seems to hold boost very well and idles well also. Also, I have the VTA vaccum port capped off. Should I uncap it? It does have some weird high RPM part throttle flutter though. Should I tighten it down more to cure that? Will it adversely affect idle if I do? Thanks.
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#8
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Originally Posted by EVOTEXAS
I run the single spring mod and don't have the spring screwed even half as far as burningmoney. I have HKS 264s and it seems to hold boost very well and idles well also. Also, I have the VTA vaccum port capped off. Should I uncap it? It does have some weird high RPM part throttle flutter though. Should I tighten it down more to cure that? Will it adversely affect idle if I do? Thanks.
#9
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When i bought my car it had a Pruven Performance BOV on there (identical to the Type-S) with both springs in and the Idle SUCKED!!! Stalled out if i let off on the gas partially spooled. I slapped in my Type-S from my GST after i did the single spring mod, Turned it 3.5 turns past first contact and it works BEAUTIFUL!! Get a very small flutter at like 1 or 2psi but other then that no problems. Recirculated with the Lower nipple not hooked up & not capped. Pressure tested and it works just as the write up says it should.
#11
Originally Posted by EVOTEXAS
I run the single spring mod and don't have the spring screwed even half as far as burningmoney. I have HKS 264s and it seems to hold boost very well and idles well also. Also, I have the VTA vaccum port capped off. Should I uncap it? It does have some weird high RPM part throttle flutter though. Should I tighten it down more to cure that? Will it adversely affect idle if I do? Thanks.
i would keep the VTA vaccum capped off if i didnt have it recirculating
does anybody else use the lower vaccum nipple as re-circulating?
Last edited by burningmoney97; Dec 29, 2004 at 01:28 PM.
#13
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I have just the single spring in and turned from 2.5 - 4 turns from initial contact and didn't notice much change in those adjustments. All worked fine for me with no compressor surge or stalling on an otherwise stock evo
#15
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Originally Posted by Smogrunner
I'd love to race any of you in the 1/4 regardless of turbo or mods if you only have the single spring installed.
why would you pick a race based on if they have the single spring or not? I have the single spring. Seems to work fine for me...Yet I havent tried putting the other spring back in either though.