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How much boost for BPU+?

864 Views 6 Replies 6 Participants Last post by  SupraT04r
Ok so lets say that youve got a good BPU car with a GReddy 3-row or something along those lines, what is a safe boost setting to run on the stock turbos? I am asking about a safe amount of boost that you can run all the time. At what point do the stock turbos lose their efficiency (as far as boost)? Thanks for the info.
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All the answers you seek (and more) can be found right here.
This is kind of a subjective question, but I run around 17-18. I'm also at a mile-high altitude, so it's difficult to overboost over 20 except on chill days. I've spiked to 22 or so, but normal I'm right around 1.25 kg/cm2 at WOT.

As far as what's "safe", I've read in the past (on MKIV mail-list) that 16-17psi is pretty safe on stock-twins if you want to have them last. I'm only at 60k miles, but I'm sure at 100k, you probably don't wanna boost higher than that, very often.
Thanks very much for the replies, and I did search for answers to my question but couldn't come up with much.
i say no more than 18psi anymore and your beyond the safe zone

some say 19psi but i think thats in the red zone already for boost. with stock twins.

but like DJ dZ posted use the search button next time we have spoken about this many many times.

also check out mkiv.com they talk about this as well

here is what they had to say.

http://www.mkiv.com/faq/faqtt.html#bpu1

"...you will also want to install a boost gauge to monitor how much boost you are running. obviously running more boost is going to decrease the life of your turbos (by how much is not really known) so you will want to watch this. a few turbos don't last long at all at higher than stock boost levels, but most seem to take the increased boost just fine. most people think the best trade off is no more than 18 psi although some have had success and longevity with higher boost. a conservative number would be to run 15 psi low boost with occasional runs to 17 psi if you get an ebc that is easily adjustable on the fly. even with a supra, you gotta be willing to pay to play...
back to start "
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18 with pump, 19 with race gas. make sure your boost doesn't spike past 19.

-Brett
18 psi seems to be the magic number. That is what I boosted at all the time and my turbos still looked ok when I took them out at 120k
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