Spool Time
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
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From: Newmarket, Ontario
Spool Time Hey fellow turbo guys, got a question...
If you put it in say 4th-5th gear doing 30mph (simulate long roll on) and go WOT, at what rpm do you start seeing 0.5psi (beginning of boost) and at what point do you see full psi (and what is full psi for your setup)?
If you put it in say 4th-5th gear doing 30mph (simulate long roll on) and go WOT, at what rpm do you start seeing 0.5psi (beginning of boost) and at what point do you see full psi (and what is full psi for your setup)?
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
Likes: 0
From: Newmarket, Ontario
Anyone (Before I get my car tuned I want to be sure everything is alright - spool time and all)?
I have not been able to bring my car into high boost (having not been tuned yet), but when I try to see how long it takes to get into boost it builds delayed but fast. What I mean is I do not see any until about 3000-3500 rpm but it jumps to 4-5 from the time I start to see the needle start to move to the time I pull my foot off it, it rises MUCH faster then the procharger I used to have, any comments/answers to my first question?
I have not been able to bring my car into high boost (having not been tuned yet), but when I try to see how long it takes to get into boost it builds delayed but fast. What I mean is I do not see any until about 3000-3500 rpm but it jumps to 4-5 from the time I start to see the needle start to move to the time I pull my foot off it, it rises MUCH faster then the procharger I used to have, any comments/answers to my first question?
I don't think it's such a good idea to go WOT at that high of a gear, with that low of an rpm. You would be putting an incredible load on the motor. But, the questions you are asking have a ton of variables involved. For example, different a/r's, even if it's still a GT42, will spool at different times. I know that doesn't answer your question, but I figured I'd at least chime in! 
Thread Starter
TECH Apprentice
Joined: Nov 2005
Posts: 304
Likes: 0
From: Newmarket, Ontario
Thanks I was getting lonely posting to myself... I realize the setup plays a huge role, I was just curious how other setups are, and if I am in the ballpark, how does your STS respond?
Well, I am in the middle of breaking in the motor, so I haven't gotten into it yet. But, I did log some data a few days ago, and I hit 85% throttle, and the GT76 started to boost around 3200, and hit 4.5# (that's where my boost controller is set for the break-in) by 3550 rpm. I figure I should hit full boost (say 12 psi) before 4k. Now, I have a really big turbo with a large a/r, especially for a rear mount. So, I would assume something smaller should spool quicker. Hope that helps.
