Controlling boost while spooling

Bbuchanan11

Active member
Sep 9, 2011
251
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Sarver, PA
Ok guys this might be a dumb question but when I’m spooling at the line I hit a certain rpm where the boost just wants to take off and constantly push through the brakes. It makes for very inconsistent staging and if I’m not right at that point when launching it almost bogs down.. my question is can I dump the boost to get to a higher rpm without pushing through? If it is something I can do I’m sure it’s been done but I couldn’t find any information on it. Would I have to do it on the exhaust side or could it be done on the pressure side? I was thinking of a waste gate or blow off valve that I could control with a button hold it open when spooling and then let off the button when I launch. Thanks for any advice
 

JoshH

Daggum farm truck
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Not a lot you can do to control boost, but you should be able to control it with fueling. I would imagine that has more to do with it than the boost anyway.
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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you need something like a 3 or 4 port boost controller and a waste gate on each turbo (unless its only the secondary turbo making boost at spool up). then you need a computer to drive it. not sure if there is a standalone for it but i know you could retrofit a megasquirt ecm to do it.

Fuel tech also has a pretty cool fully electric wastegate that is extremely quick and good at holding boost where you want it. you would need to go away from the factory ecm all together to do it but that allows you to add a 2 step/launch control to be really accurate at the tree. there are a few other standalones that could do that as well.

kinda sounds like your converter is on the tight side as well? a little looser stall will give you more play area to control boost with your foot.
 

Bbuchanan11

Active member
Sep 9, 2011
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Sarver, PA
I have talked to George about the trans before. It was already built before I got it. I got the serial number off of the converter when I had the engine out and called precision to get the specs on it… I have thought about the 2nd gear start before but never pulled the trigger. How bad is it on a converter?
 

JoshH

Daggum farm truck
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Who is tuning the truck? Have you talked to them about your issue? I experienced this problem on an LB7 not too long ago. It seemed to be a boost issue, but it ended up being related to the way the tuner was ramping up rail pressure with RPM causing an increase in fueling without an increase in throttle position.
 

S Phinney

Active member
Aug 15, 2008
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Quncy, Fl
Second gear start will help you but going to a 25-2700 stall convertor would help as well.


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Bdsankey

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Feb 1, 2018
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I've had good luck lately with a Goerend BF over a K. For me it always seemed that the K would never get up to it's full stall unless you had a very small drop in VGT or a tight set of compounds (like 364.5 area) whereas the BF has met that goal every time of being a nice middle ground between an R and a J.
 

Ne-max

I like turtles
Nov 15, 2011
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Lincoln, Ne
I've had good luck lately with a Goerend BF over a K. For me it always seemed that the K would never get up to it's full stall unless you had a very small drop in VGT or a tight set of compounds (like 364.5 area) whereas the BF has met that goal every time of being a nice middle ground between an R and a J.

BF? Isn't that a Ford converter?