Boost Controller
Thread Starter
Instructor
Joined: Apr 2006
Posts: 169
Likes: 0
From: Brighton Mi
Boost Controller
I have a LS1 with cam, headers and STS twin turbos. The wastegate is F8 TIAL with a .7 BAR (10.2psi) spring. I take the vette to my tuner (he is the best) and after he finishes the graph shows 530whp. The problem is the wastegate opens at 10psi but then the wastegate can’t control the boost after that. The boost oscillates between 7 and 9 psi with the average of about 8.5psi. The engine is capable of handling 10psi so I don’t want to settle for 8.5psi.
I email TIAL tech support and they respond that I need a larger wastegate. I can’t do that because the wastegate mounting in the exhaust is designed to only take the F8 TIAL.
I am thinking a mechanical boost controller may fix my problem. I am asking the Forum members if they think that a mechanical boost controller will solve my problem. If it will solve my problem, what controller do you recommend?
Thanks for your help.
I email TIAL tech support and they respond that I need a larger wastegate. I can’t do that because the wastegate mounting in the exhaust is designed to only take the F8 TIAL.
I am thinking a mechanical boost controller may fix my problem. I am asking the Forum members if they think that a mechanical boost controller will solve my problem. If it will solve my problem, what controller do you recommend?
Thanks for your help.
Safety Car
Joined: Aug 2000
Posts: 4,537
Likes: 84
From: St. Joseph MO
Cruise-In III Veteran
Cruise-In IV Veteran
You can use a cheap $10 Ebay to a $150+ Hallman to test your theory. I'd believe a mechanical Hallamn would work well, bu tthe cheapest one is like $65. Turbosmart and a couple other manufacturers all sell manual controllers.
I use TurboSmart Eboost Street controllers in my turbo vehicles.
I use TurboSmart Eboost Street controllers in my turbo vehicles.
Burning Brakes
Joined: May 2011
Posts: 1,216
Likes: 56
From: Houston Texas
I'm actually pulling the Eboost Street out of mine currently in preparation for the Haltech switch. I'll cut you a deal on a very lightly used Eboost street if you're interested. Have 2 boost solenoids for it. Shoot me a PM if interested.
The eboost has a setting to accommodate boost falling off up top. Splice into rpm signal, tell it what rpm the boost starts to drop from target, and give it a pressure ratio for the amount dropped. Done. Not uncommon for running just springs, or even mechanical controller.
The eboost has a setting to accommodate boost falling off up top. Splice into rpm signal, tell it what rpm the boost starts to drop from target, and give it a pressure ratio for the amount dropped. Done. Not uncommon for running just springs, or even mechanical controller.
Burning Brakes
Joined: Sep 2011
Posts: 764
Likes: 19
From: odessa FL
I have almost the exact same setup and power level and upgraded turbos. Gauge is steady at 10 with a mechanical controller
I seriously doubt the size of the gate is your problem if its to air rather than an exhaust system
I am looking into an electronic controller for better spool, at least 2 power settings and possibly boost by gear for my new build. Leaning toward the HKS or Apexi.
I have also considered a 2nd gate with a mech controller as a safety just in case
I seriously doubt the size of the gate is your problem if its to air rather than an exhaust system
I am looking into an electronic controller for better spool, at least 2 power settings and possibly boost by gear for my new build. Leaning toward the HKS or Apexi.
I have also considered a 2nd gate with a mech controller as a safety just in case
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
I don't understand why your boost is oscillating under your target and you're told you need a larger wastegate. My experience is when the wastegate is too small, your boost creeps above your target, not below.
Have you or your tuner performed a boost-leak test? You can clamp caps on both turbo inlets, pull your brake booster line and hit it with boost from there. If you have a boost leak, it could cause this issue and destroy your turbos, making them over spin and ride the choke line to their death.
Have you or your tuner performed a boost-leak test? You can clamp caps on both turbo inlets, pull your brake booster line and hit it with boost from there. If you have a boost leak, it could cause this issue and destroy your turbos, making them over spin and ride the choke line to their death.
Thread Starter
Instructor
Joined: Apr 2006
Posts: 169
Likes: 0
From: Brighton Mi
I have almost the exact same setup and power level and upgraded turbos. Gauge is steady at 10 with a mechanical controller
I seriously doubt the size of the gate is your problem if its to air rather than an exhaust system
I am looking into an electronic controller for better spool, at least 2 power settings and possibly boost by gear for my new build. Leaning toward the HKS or Apexi.
I have also considered a 2nd gate with a mech controller as a safety just in case
I seriously doubt the size of the gate is your problem if its to air rather than an exhaust system
I am looking into an electronic controller for better spool, at least 2 power settings and possibly boost by gear for my new build. Leaning toward the HKS or Apexi.
I have also considered a 2nd gate with a mech controller as a safety just in case
Thread Starter
Instructor
Joined: Apr 2006
Posts: 169
Likes: 0
From: Brighton Mi
I have almost the exact same setup and power level and upgraded turbos. Gauge is steady at 10 with a mechanical controller
I seriously doubt the size of the gate is your problem if its to air rather than an exhaust system
I am looking into an electronic controller for better spool, at least 2 power settings and possibly boost by gear for my new build. Leaning toward the HKS or Apexi.
I have also considered a 2nd gate with a mech controller as a safety just in case
I seriously doubt the size of the gate is your problem if its to air rather than an exhaust system
I am looking into an electronic controller for better spool, at least 2 power settings and possibly boost by gear for my new build. Leaning toward the HKS or Apexi.
I have also considered a 2nd gate with a mech controller as a safety just in case
Melting Slicks
Joined: Mar 2006
Posts: 2,752
Likes: 377
From: South Florida FL
I don't understand why your boost is oscillating under your target and you're told you need a larger wastegate. My experience is when the wastegate is too small, your boost creeps above your target, not below.
Have you or your tuner performed a boost-leak test? You can clamp caps on both turbo inlets, pull your brake booster line and hit it with boost from there. If you have a boost leak, it could cause this issue and destroy your turbos, making them over spin and ride the choke line to their death.
Have you or your tuner performed a boost-leak test? You can clamp caps on both turbo inlets, pull your brake booster line and hit it with boost from there. If you have a boost leak, it could cause this issue and destroy your turbos, making them over spin and ride the choke line to their death.
based on the logic you got from Tial. the wastegate is too big and bleeding off too much.
But I wouldn't overthink it, try a boost controller
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Thread Starter
Instructor
Joined: Apr 2006
Posts: 169
Likes: 0
From: Brighton Mi
Thanks for everyones help and advice. It looks like I need to install a boost controller. The one thing I don't understand about electronic boost controllers is that some manufactures claim to be able to increase the turbo spool up. I don't understand how this is possible. My understanding is that the spool up is limited by the volume of exhaust gas spinning the exhaust side of the turbo. Can an electronic boost controller actually increase your spool up? If they can increase spool up, how is this done?
Safety Car
Joined: Aug 2000
Posts: 4,537
Likes: 84
From: St. Joseph MO
Cruise-In III Veteran
Cruise-In IV Veteran
Thanks for everyones help and advice. It looks like I need to install a boost controller. The one thing I don't understand about electronic boost controllers is that some manufactures claim to be able to increase the turbo spool up. I don't understand how this is possible. My understanding is that the spool up is limited by the volume of exhaust gas spinning the exhaust side of the turbo. Can an electronic boost controller actually increase your spool up? If they can increase spool up, how is this done?
Thread Starter
Instructor
Joined: Apr 2006
Posts: 169
Likes: 0
From: Brighton Mi
Say you have an 8# wastegate spring. Usually the spring will start to creep open at say around 5-6#'s and progressively open full by 8#'s. With a boost controller the wastegate isn't allowed to vent/move until there's enough pressure to overcome the wastegate spring and controller combo. That is where the claims for increased spool come from.
Burning Brakes
Joined: Sep 2011
Posts: 764
Likes: 19
From: odessa FL
The thinking with the electronic boost controls helping spool is that they stay shut untill the target due to the solenoid, whereas the wastegate spring begins to open sooner left to its own devices.
Melting Slicks
Joined: Jul 2004
Posts: 2,844
Likes: 144
From: Northern Ireland
I have a LS1 with cam, headers and STS twin turbos. The wastegate is F8 TIAL with a .7 BAR (10.2psi) spring. I take the vette to my tuner (he is the best) and after he finishes the graph shows 530whp. The problem is the wastegate opens at 10psi but then the wastegate can’t control the boost after that. The boost oscillates between 7 and 9 psi with the average of about 8.5psi. The engine is capable of handling 10psi so I don’t want to settle for 8.5psi.
I email TIAL tech support and they respond that I need a larger wastegate. I can’t do that because the wastegate mounting in the exhaust is designed to only take the F8 TIAL.
I am thinking a mechanical boost controller may fix my problem. I am asking the Forum members if they think that a mechanical boost controller will solve my problem. If it will solve my problem, what controller do you recommend?
Thanks for your help.
I email TIAL tech support and they respond that I need a larger wastegate. I can’t do that because the wastegate mounting in the exhaust is designed to only take the F8 TIAL.
I am thinking a mechanical boost controller may fix my problem. I am asking the Forum members if they think that a mechanical boost controller will solve my problem. If it will solve my problem, what controller do you recommend?
Thanks for your help.
Fix the actual problem, dont try and band aid it.
