G40 boost preasure

[Oli b]

Hi my g40 engine has had 65 mm pulley jabbasport chipped ecu and stage 4 jabbasport charger ( rebuilt around 10k miles ago)
Boost gauge shows 0.9 bar when on full throttle and creeps up to 1.0 bar near the redline
Is that a good amount of boost for this spec ?
Cheers

[Jezza-7]

Yes. My R1 charger was boosting 14/15 psi and near redline was getting 18/19psi.

[ereeiz]

About the same for me too, I get about 1.0 bar creeping to 1.1 near the limiter. Full blend, 65mm toothed belt kit and cheapo Autogauge boost gauge

[Richg40]

1.1 bar, ported myself with 65mm pulley.

[Jake G 4 0]

Are you guys using toothies or standard v belts??  Or have I just got a massive boost leak??

[Jezza-7]

Toothies.

[ereeiz]

Think it peaked about 0.8 or 0.9 with 65mm pulley and tight vee-belts for ten miles or so then they'd slack off/stretch.

[hayesey]

I never saw more than 15psi on mine when it had a g-lader and 65mm pulley with toothies on it.  I'd question the boost gauge accuracy if you are seeing 18/19psi on it

It went down to 13/14 when I put a gt inlet and de-wedged the throttle body, as you'd expect.

[Jezza-7]

Nothing wrong with my gauge. Think it would be rare for a stack gauge to be inaccurate.

My boost is now 10-11 psi, running 51mm tb, gt inlet, ported head and 1341 bottom end.

[Dan-G40]

Used to get 14psi at the red line on my old G with a 65mm pulley and tight v belts (PSD Full Blend)

[AlexG40]

It does depend a lot on the rest of the engine. My R1 used to pull 17psi on a stock engine.

[ereeiz]

Remember the accuracy of the gauge too, I'd bet most the ones used are just naff cheap ones like mine So the components used will have poor tolerances and variations in results, so if you're a few PSI/0.1bar' off someone with similar/ same mods then i'd put it down to that.

Best way to tell is do an identical drive in the other car and swap gauges, see if you get the same results in both. Even then there's no guarantee that either is correct, they could both be off :p

[alan gorst]

i get 10psi on a jabba stage 4 charger with standard pully

[JIMMYP]

if u have had a stage 4 rebuild do u need the higher co pot sensor?

[hayesey]

the what? shouldn't have to do anything to the CO pot.