What boost do you run ?

GTR-boy · Post by **GTR-boy** » Wed Nov 06, 2002 4:50 pm

What boost do you run and what effects boost on the G40 ?

Mine runs at 0.6 bar - does anyone know what is standard ?

fil_rite13 · Post by **fil_rite13** » Wed Nov 06, 2002 6:54 pm

0.6 bar is standard boost at full throttle i think???

sixspeed · Post by **sixspeed** » Thu Nov 07, 2002 1:33 am

Mine was running about 1.15bar of boost at its best, but the belts are slipping now and its down to just under 1.0bar at redline.

Plan to fit some toothed belts to eliminate slip altogether, which should bring it back up again.

Boost is essentially controlled by how fast the charger is spinning. Fitting a smaller pulley will up the boost. However, you can also have your charger rebuilt, and in the process have the inlets enlarged and/or ported/polished which will also see a gain in boost.

Jabbasport are the main company in the UK to do this work for you - though there are others...

-andy-

GTR-boy · Post by **GTR-boy** » Thu Nov 07, 2002 9:14 am

Andy - What size pulley are you running to get 1.15 ?

The pulley on my car is 68mm.

Do you have any other goodies on your car ?

Tim B

sixspeed · Post by **sixspeed** » Thu Nov 07, 2002 12:03 pm

I have a 65mm pulley and an R1 Jabbasport charger.

-andy-

JellyB · Post by **JellyB** » Sun Dec 15, 2002 4:35 am

Do you really recommend the R1?

Mine is having a rebuild in the new year (soon as I can book it and sort out another car!) not sure what to go for, a stage4 or the R1. Want to have at least another 40k out of the charger so which would you guys recommend for long service life?

ta

poloace · Post by **poloace** » Fri Aug 29, 2003 4:12 am

I was getting about 0.55 to 0.6 before my rebuild and toothed 65mm pulleys. I had my charger rebuild by Steve at www.Pitstopdevelopments.co.uk they are a bit cheaper than Jabba and do a real good job and can lend a charger while they do yours

It was given ther full blend treatment, I have now fitted a GT inlet manifold which decreses back pressure and boost and I get over 1.1bar at full pelt. The car goes like a rocket, I thought it wa quick before!

amstrange1 · Post by **amstrange1** » Tue Oct 21, 2003 12:19 am

I get 0.8bar at 6k, standard pulley but S4 charger I think. Got to get Pitstop full blend!

Gary · Post by **Gary** » Tue Nov 18, 2003 3:57 am

I get approx 1.1 bar at the redline!.......... pulls like a train!

hayesey · Post by **hayesey** » Thu Nov 20, 2003 10:43 pm

I'll tell you in a couple of days when my boost gauge arrives!

got a feeling it aint gonna be good though cos I think I've got a boost leak

but if it turns out there isnt a leak hopefully should be OK with stage 4, 65mm pulley & toothed belts.

paulG40 · Post by **paulG40** » Sat Nov 22, 2003 7:14 pm

Boost can depend alot on the inlet port sizes and TB sizes etc mine has had a stage 3 head which has opened it up a huge amount and the valves have been profiled, it's also got a gt inlet manifold which has been opened up abit. the charger is full blend with 65mm toothed pulleys. It's creating 0.9 bar at full revs, which is brilliant in terms of the amount of air getting into the engine.

hayesey · Post by **hayesey** » Mon Dec 01, 2003 6:59 pm

mines about 0.9bar. 13-14psi on my boost gauge.

hardhitter · Post by **hardhitter** » Mon Dec 01, 2003 7:51 pm

Thats pretty good going for the spec, Hayesey.

Those toothed belts make such an improvement plus they sound wicked.

amstrange1 · Post by **amstrange1** » Mon Dec 01, 2003 9:49 pm

hayesey wrote:mines about 0.9bar. 13-14psi on my boost gauge.

What revs is that at? Bet it's lower than my 0.8 at 6k rpm, gotta get me some toothed belts!

hayesey · Post by **hayesey** » Thu Dec 04, 2003 10:10 pm

no, its at about 6k andy. it gets to about 11-12 psi pretty much straight away & then slowly builds up to 13.5-14 after that, well i say slowly but its in a matter of about 1 or 2 secs.

so it builds upto almost full boost much earlier than 6k. but I'm going to start tearing my hair out soon if i dont get my bloody twin inlet collars!