2# of Boost WTF?
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Joined: Nov 2001
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From: Sunny San Diego
2# of Boost WTF? Where are you guys tapping into for the ATI Surge Valve?
I have both the boost gauge and valve tapped into the brake booster. My vendor says I should move it.
I have both the boost gauge and valve tapped into the brake booster. My vendor says I should move it.
How tight do you have the belt??? You are getting built slip or you have lots od mods on your car...... The 5# pulley is for 5#'s on a stock car...... what size in iches is it...... I saw 4 psi with my 4" pulley along time ago........ I tap right into the back of the intake for both my boost gauge, surge valve, and by ref regulator.
Kyle
Kyle
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Joined: Nov 2001
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From: Sunny San Diego
That was the first thing I thought belt. I tighten it really tight, could only move it about a 1/4 in. No difference. So I loosened it back up. Didn't want it too tight.
I think the pulley size is 4.10 I'll verify it today when I get home.
I told the vendor my mods and that I wanted 5# of boost.
They think the surge valve is not closing @ WOT. And I should move the line to the TB.
I think the pulley size is 4.10 I'll verify it today when I get home.
I told the vendor my mods and that I wanted 5# of boost.
They think the surge valve is not closing @ WOT. And I should move the line to the TB.
That might be it but that pulley is smaller them what mine came with when i first bought my hit........ I only made 4 psi with a 4" pulley, LT's, no cats, Catback,and a baby 212/218 cam........ You might need to go with a bigger pulley.
Kyle
Kyle
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Originally Posted by Ed LS1 Vert
I have the 5# pulley. I see 1.5# - 2# when I first floor it and Stays at 2# all the way to 6300 rpms
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A 4.1 on a P1SC will only give you a couple pounds, a 3.4 with a stock motor/headers will give you 6 or 7. If you want 5psi a 3.6 would probably work out.. I wouldnt go any larger then a 3.4 to be honest, you will just end up buying another pulley soon 
I run a reichard 3.2, no slip issues at all at 7.5-8.5psi @ 6500.
I run a reichard 3.2, no slip issues at all at 7.5-8.5psi @ 6500.
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Verdad Gallardo Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
Must be my mods that is killing the boost. Grrrr, I told them that I had mods. 
I'll check into a 3.4 and 3.2 pulley.
Could I just unplug my vacuumn line to my surge valve for one run to check?? Won't hurt anything will it?
Thanks guys.
I'll check into a 3.4 and 3.2 pulley.
Could I just unplug my vacuumn line to my surge valve for one run to check?? Won't hurt anything will it?
Thanks guys.
if your boost guage works and its hooked to the same place as the surge valve the surge valve is working ok.
I dont think they would have given you a 4.1 pulley, the pulley size will be marked on the parts list that came with the blower..
Altitude has a lot to do with it also, I used to see a little over 8psi with a 3.4 at sea level, here I never seen over 7 with a 3.4 at ~1500'
I dont think they would have given you a 4.1 pulley, the pulley size will be marked on the parts list that came with the blower..
Altitude has a lot to do with it also, I used to see a little over 8psi with a 3.4 at sea level, here I never seen over 7 with a 3.4 at ~1500'
Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
They said that the brake booster was still creating vacuumn and that I need to be further away from it. And that the valve was not closing completely. That didn't make sense since I was showing boost. Does it matter which way it is mounted? Instructions say nut on the butterfly points to the J-Tube. Pics show the reverse.
Could I lose any boost through the PCV valve? (I have a check-valve on order)
The parts list show the 4.1 pulley.
I am pretty close to sea level.
Thanks.
And that the valve was not closing completely. That didn't make sense since I was showing boost. Does it matter which way it is mounted? Instructions say nut on the butterfly points to the J-Tube. Pics show the reverse.Could I lose any boost through the PCV valve? (I have a check-valve on order)
The parts list show the 4.1 pulley.
I am pretty close to sea level.
Thanks.
Last edited by Ed LS1 Vert; May 11, 2004 at 01:32 PM.
Thread Starter
Joined: Nov 2001
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From: Sunny San Diego
Decided to call ATI on the issue. Their records showed I only had H/C's and no Headers. So they sent me the 4.1 pulley. They are now going to send me a 3.7, which should take me to 5#.
Hopefully that will take care of it. Thanks guys and thanks ATI. (Didn't know you guys read this site. Better watch what I say. )
Hopefully that will take care of it. Thanks guys and thanks ATI. (Didn't know you guys read this site. Better watch what I say.
) Last edited by Ed LS1 Vert; May 12, 2004 at 10:55 AM.
The brake booster line is fine, it has a check valve that closes at boost.
You are losing a little through the pcv, not much though. The crankcase being pressurized is the bad thing.
Glad ATI got you fixed up..
You are losing a little through the pcv, not much though. The crankcase being pressurized is the bad thing.
Glad ATI got you fixed up..
Did they charge you for the other pulley??? I hate there...... nothing other then 2 day air crap........ $18 bucks for a crank bolt and washer........... $6 bucks for the parts and 12 for shipping..... It just erks me..
Kyle
Kyle
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From: Marysville, WA
I know you will get lots of good opinions, don't be disappointed if it take a few tries to get what you want with boost. It takes time and trial and error.
It soulds like ATI is stepping the pulley one size at a time (from their pulley selection) for you to safely get where you want. The 3.8 probably will not quite get you where you want, don't be up set. I am thinking 3.6 or 3.4 will do it for you. I am leaning toward you needing the 3.4 pulley.
I was running the same boost you are with the 4.1 = 2# (reading the gauge is not easy because of it's size but it was close to this) The 3.4 got me to 5# of boost. These readings were with my stock LS6 intake. When I changed to my Lingenfelter intake my boost went down, (the volume is greater in the intake) then I bought the MMS pulley to bring boost back up.
Remember, you are not experiencing anything out of the norm. Mods always change boost. It will take a little time to get it where you want.
Thanks for the compliments on my engine compartment, show has always been my first goal. Like I said before no I am getting into the tuning aspect.
Good luck!
It soulds like ATI is stepping the pulley one size at a time (from their pulley selection) for you to safely get where you want. The 3.8 probably will not quite get you where you want, don't be up set. I am thinking 3.6 or 3.4 will do it for you. I am leaning toward you needing the 3.4 pulley.
I was running the same boost you are with the 4.1 = 2# (reading the gauge is not easy because of it's size but it was close to this) The 3.4 got me to 5# of boost. These readings were with my stock LS6 intake. When I changed to my Lingenfelter intake my boost went down, (the volume is greater in the intake) then I bought the MMS pulley to bring boost back up.
Remember, you are not experiencing anything out of the norm. Mods always change boost. It will take a little time to get it where you want.
Thanks for the compliments on my engine compartment, show has always been my first goal. Like I said before no I am getting into the tuning aspect.
Good luck!
Thread Starter
Joined: Nov 2001
Posts: 3,066
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From: Sunny San Diego
I understand that every car is different. But it was obvious they sent the wrong pulley. They are sending me a 3.7 pulley. (Typo from before) Well, if it doesn't get me to 5#. I'll call ATI again.
And I just ordered a 3.2 pulley. Just in case I want more. And we all do.
Which is the best way to go? Smaller blower pulley or larger crank pulley? Time to go search.
Thanks.
And I just ordered a 3.2 pulley. Just in case I want more. And we all do.
Which is the best way to go? Smaller blower pulley or larger crank pulley? Time to go search.
Thanks.
Tech Addict
Joined: Dec 2001
Posts: 3,205
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From: Marysville, WA
Originally Posted by Ed LS1 Vert
I understand that every car is different. But it was obvious they sent the wrong pulley. They are sending me a 3.7 pulley. (Typo from before) Well, if it doesn't get me to 5#. I'll call ATI again.
And I just ordered a 3.2 pulley. Just in case I want more. And we all do.
Which is the best way to go? Smaller blower pulley or larger crank pulley? Time to go search.
Thanks.
And I just ordered a 3.2 pulley. Just in case I want more. And we all do.
Which is the best way to go? Smaller blower pulley or larger crank pulley? Time to go search.
Thanks.