Boost drop off in radix lq4

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Oct 26, 2006 | 10:01 AM

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Boost drop off in radix lq4

Is it common to see boost drop off in the upper rpm range. From 1500-4500 rpm I am seeing about 8-8.5 psi of boost. As it gets to 5-6000rpm, is goes down to about 7 psi at redline. Is this typical??

Oct 26, 2006 | 10:26 AM

moregrip

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From: Wyoming

I have heard others say similar things. However, I have not personally seen this, I build to 7lbs, and stay there.

Oct 26, 2006 | 10:28 AM

dewmanshu

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it happens to me, i have less boost than i start with, BUT...you sure you aren't suffering from belt slip or crank pulley spinning?

Oct 26, 2006 | 10:33 AM

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Quote:

Originally Posted by dewmanshu

it happens to me, i have less boost than i start with, BUT...you sure you aren't suffering from belt slip or crank pulley spinning?

Running a 110.5" gatorback belt and I do not see any belt dust. The crank pulley is pinned. Maybe try another belt. This one is about a year old.

Oct 26, 2006 | 12:22 PM

Holty

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i'm running 100mm metco idlers, crank pulley pinned, and a 111.5" gator back with a 2.8" pulley. At 6k rpm i'm at 8psi and it holds steady and somtimes goes up a tad. In the dead of winter, i'll see 9psi.

Oct 26, 2006 | 01:08 PM

dewmanshu

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you have a scan of this happening?

Oct 26, 2006 | 02:47 PM

trever1t

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I do, posted in the Dyno section.

Boost drop off in radix lq4

Boost drop off in radix lq4

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