Which Forge BOV Spring?
#1
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I have a Forge BOV from the group buy last summer, and was planning to install it soon. Which spring should I use for 15 to 20psi of boost? It came with the green spring installed -- and am wondering if I should start with one of the stronger ones.
#2
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Hmm.. I didn't even really give this any thought :P I just installed mine with the default (apparently green) spring.. I'll have to check next time I see my car (prolly this weekend). I would comment, but I think I've still got boost leaks all to hell, so yeah.. Dunno if thats contributing to it or not.
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I'm interested in this too. I would think you would want the wastegate to start opening before your desired boost level to prevent overboost, but if you're using an EBC, I think it has ways to open the valve at the optimum time in which case your spring is only used for a backup setting (in which case you'd want it lower than your regular boost setting).
Of course, like I said, I'm interested in the responses from someone who knows more about it that me.
Of course, like I said, I'm interested in the responses from someone who knows more about it that me.
#5
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Originally Posted by Silberner Turbo
Simple, equal the spring rate to the inches of mercury at idle. Ideally you want a 9-10 psi spring.
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Originally Posted by danny951
I'm interested in this too. I would think you would want the wastegate to start opening before your desired boost level to prevent overboost, but if you're using an EBC, I think it has ways to open the valve at the optimum time in which case your spring is only used for a backup setting (in which case you'd want it lower than your regular boost setting).
Of course, like I said, I'm interested in the responses from someone who knows more about it that me.
Of course, like I said, I'm interested in the responses from someone who knows more about it that me.
As for wastegate control, I recommend the original Profec B
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Originally Posted by Tom M'Guinn
I have 17 - 18 hg at idle, give or take. How does that equate to a spring rate and/or the 9-10 psi spring?
https://rennlist.com/forums/showthre...ferrerid=14903
You should be using the green spring IIRC. I have the same BPV.
#10
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Originally Posted by ehall
Tom take a look at this old thread on page 3 and four.
https://rennlist.com/forums/showthre...ferrerid=14903
You should be using the green spring IIRC. I have the same BPV.
https://rennlist.com/forums/showthre...ferrerid=14903
You should be using the green spring IIRC. I have the same BPV.
#11
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I'm using the spring that came in it. I'm not sure what color it was, but it was NOT blue, green or red. I think it was yellow and I believe it is 0.8 bar (11-12 psi). It works great at 15-17 psi boost.
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Originally Posted by lart951
Page 3? there is nothing in reference to the spring there.
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Originally Posted by Silberner Turbo
One inch of mercury = 0.4911541 of a psi. You need circa 8.5psi spring.
I understood that the spring options related to boost pressure. If not, it seems odd to offer so many spring rates -- since most cars have similar levels of vacuum. No?
#15
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okay - here it is;
-You must installl the valve with the pressure to the SIDE port of the unit.
(in this way, it will not act directly upon the diaphragm)
-You should use the green spring (weakest) because you are not directly countering the spring via the diaphragm, you use the weakest spring WHICH WILL NOW YIELD THE FASTEST RESPONSE (boost recovery) time.
-installation in this manner results in a win/win situation, the ONLY compromise is slightly reduced diaphragm life. This a VERY easily serviced diaphragm (2 minutes), and the unit comes with 3 of them.
-You must installl the valve with the pressure to the SIDE port of the unit.
(in this way, it will not act directly upon the diaphragm)
-You should use the green spring (weakest) because you are not directly countering the spring via the diaphragm, you use the weakest spring WHICH WILL NOW YIELD THE FASTEST RESPONSE (boost recovery) time.
-installation in this manner results in a win/win situation, the ONLY compromise is slightly reduced diaphragm life. This a VERY easily serviced diaphragm (2 minutes), and the unit comes with 3 of them.
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