Low Boost 5psi max

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Feb 23, 2008 | 09:55 PM

LBCMS

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Low Boost 5psi max

Whats the deal got everything going finally and im only getting 5psi max boost. cdr on intake is blocked no other gapeing holes that i know of. had to back off the IP flow screw so now its only one flat from its orignal setting rather then bottom out like before. what am i missing? i have the Hypermax kit on the 86 f250 6.9L

Feb 23, 2008 | 10:33 PM

1994diesel

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From: Central Coast CA

is it waste gated? ive been told that shortening the rod will bring up your boost, im gona try that.

Feb 24, 2008 | 12:31 AM

George D.

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From: Las vegas

I don't think the hypermax is waste gated the only way to get more boost is free up the intake and exaust and turn up the fule. also the load on the truck will afect it. I'm not too familliar with the hypermax turbos may not build full boost without a good load. Also chack for boost leaks and exaust leaks befor the turbo.

I tryed shortening the rod on my waste gate but I'm still maxing a 7psi full throtle empty and it gets there quick so Next I'm gona turn the fule up a bit and see what hapens.

Feb 24, 2008 | 09:02 AM

Dave Sponaugle

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From: Nutter Fort, WV

George do you still have the stock down pipe on your turbo?

That smashed pipe will make the turbo spool slow and limit the max boost.

Feb 24, 2008 | 09:59 AM

84-6.9

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From: with the cows

When I put my kit on with the pump open 1 1/2 flats 5pis was it, open it to 21/2 and you should see 8 psi and the boost guage needle should be a little more lively.

Feb 24, 2008 | 10:06 AM

Dave Sponaugle

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From: Nutter Fort, WV

Non wastegated turbos have four things that limit boost.

The design of the turbo
Exhaust restriction
Intake restriction
The amount of fuel burnt making heat

Feb 24, 2008 | 11:10 AM

George D.

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From: Las vegas

Yeah I'll be getting read of the squish pipe when I get my tax return.

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Feb 25, 2008 | 03:57 AM

LBCMS

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oh and the fuel flow i bottom out about 2 and 3/4 flats but i backed it off a bit about 2 flats now i had a seriuos proble previously when it was bottomed out