Only hitting 20psi
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Pro
Joined: Apr 2014
Posts: 634
Likes: 7
Only hitting 20psi
So I have a 6.1 lq9 with 15% innovators west crank and 2.75 upper pulley. I have 243 heads stock with springs, Holley Hiram, and tick stage 2 blower cam. Also have 2" headers and 3" catback. I have a proefi ecu and had a zr1 map sensor which was maxed out at 23psi. (Proefi uses 4.5 volts where as gm uses 5 volts) I upgraded to a Holley 5 bar and now it's telling me I only make 20 psi. I put it on the Dyno to make sure that it was reading correct and the Dyno says 20 psi as well. I checked for boost leaks with the compressor and a block off and checked through the throttle body and into the manifold and it seemed good. Also check from blower up to throttle body with a block before throttle body and it seemed fine.
Any ideas?? Also have a&a bracket with the earlier hd tensioner with a 10 run setup. My engine shouldn't be moving that much air to only his 20psi.
Any ideas?? Also have a&a bracket with the earlier hd tensioner with a 10 run setup. My engine shouldn't be moving that much air to only his 20psi.
Drifting
Joined: Feb 2005
Posts: 1,869
Likes: 61
From: montreal quebec
So I have a 6.1 lq9 with 15% innovators west crank and 2.75 upper pulley. I have 243 heads stock with springs, Holley Hiram, and tick stage 2 blower cam. Also have 2" headers and 3" catback. I have a proefi ecu and had a zr1 map sensor which was maxed out at 23psi. (Proefi uses 4.5 volts where as gm uses 5 volts) I upgraded to a Holley 5 bar and now it's telling me I only make 20 psi. I put it on the Dyno to make sure that it was reading correct and the Dyno says 20 psi as well. I checked for boost leaks with the compressor and a block off and checked through the throttle body and into the manifold and it seemed good. Also check from blower up to throttle body with a block before throttle body and it seemed fine.
Any ideas?? Also have a&a bracket with the earlier hd tensioner with a 10 run setup. My engine shouldn't be moving that much air to only his 20psi.
Any ideas?? Also have a&a bracket with the earlier hd tensioner with a 10 run setup. My engine shouldn't be moving that much air to only his 20psi.
Last edited by c5mtl; Apr 15, 2017 at 06:20 PM.
Melting Slicks
Joined: Jul 2004
Posts: 2,844
Likes: 144
From: Northern Ireland
So I have a 6.1 lq9 with 15% innovators west crank and 2.75 upper pulley. I have 243 heads stock with springs, Holley Hiram, and tick stage 2 blower cam. Also have 2" headers and 3" catback. I have a proefi ecu and had a zr1 map sensor which was maxed out at 23psi. (Proefi uses 4.5 volts where as gm uses 5 volts) I upgraded to a Holley 5 bar and now it's telling me I only make 20 psi. I put it on the Dyno to make sure that it was reading correct and the Dyno says 20 psi as well. I checked for boost leaks with the compressor and a block off and checked through the throttle body and into the manifold and it seemed good. Also check from blower up to throttle body with a block before throttle body and it seemed fine.
Any ideas?? Also have a&a bracket with the earlier hd tensioner with a 10 run setup. My engine shouldn't be moving that much air to only his 20psi.
Any ideas?? Also have a&a bracket with the earlier hd tensioner with a 10 run setup. My engine shouldn't be moving that much air to only his 20psi.
And have you calibrated the ecu correctly for the sensor setup you are using ?
ie get a Mityvac or similar and test it.
And was the previous setup calibrated correctly in the same manner ? If not, you may not be comparing like for like, and actual boost may be the same before/after anyway.
Last edited by stevieturbo; Apr 17, 2017 at 05:42 AM.
