Author Topic: Full blend charger boost  (Read 1895 times)

Offline g40josh

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Full blend charger boost
« on: January 28, 2015, 08:14:38 pm »
Hi
just wondering what boost people where getting with a full blend charger cheers in advance

Offline hayesey

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Re: Full blend charger boost
« Reply #1 on: January 29, 2015, 02:04:39 pm »
it depends what else has been done to the engine.  Some charger porting on it's own wont do a lot but with a smaller pulley it helps. 

The most you'll get with a g40 g-lader is about 1 bar but if you've done things like added an aftermarket cam or done any head-work then you'll actually see less because the engine is capable of drawing in more of the air the charger is pumping out (which is a good thing). 

boost pressure on a boost gauge is just the back pressure in your inlet manifold that the engine cannot consume fast enough at the end of the day.

Offline g40josh

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Re: Full blend charger boost
« Reply #2 on: January 29, 2015, 03:21:54 pm »
It has 65 mm toothed pulleys on and been told the charger has been ported but only runs 10 psi I thought it was quit low but thought it could be full blend as they run lower boost ?

Offline Jezza-7

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Re: Full blend charger boost
« Reply #3 on: January 29, 2015, 08:37:02 pm »
My spare PSD full blend was running about 12/13psi and my Jabba R1 is running 11/12psi. Thats with German steel 65mm pulleys and I'm on 1341cc, cam, ported head, gt inlet and 51mm tb.

I would of thought you'd be running around 1bar as hayesey says. Is a standard charger around 10 psi?

A few years ago i did once run at 17psi with a completely standard engine with 65mm pulleys. Seemed a bit odd but maybe the gauge was reading badly. Not normal for stack gauges though.

Offline Agent47

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Re: Full blend charger boost
« Reply #4 on: April 06, 2015, 09:40:59 pm »
To compare apples and oranges.
I have a 51mm tb, slightly ported head, gt inlet, shrick cam, and an OBD stage 2 charger and see at best 7 psi. Im pretty certain that this should be a bit more as it feels slower than my jabba stage 2 charger, and that had done 20k miles or more. Problem with different porters, no way to compare. Have to wait and check when I rebuild the jabba one.