Reading Rs4 S Boost Gauge

[SSStagea]

I have a RS4 S manual with the standard center console gauges. I understand the one on the right is the boost gauge. From what I have read, the +7 reading on this is 14.7 pound of boost? The factory settings for the NEO is as I understand, 5pound low and 7pound high, correct?

Question I have is, why would the guage be reading +7 when I give the car a bit of a hiding? This is double the amount of high boost. Would it make any difference having a GCG Hi flowed turbo with a 3 inch cat back exhaust and different dump pipe? Will using the Consult cable and software give me a boost level reading or would I need to connect another boost guage to see if everything is reading properly?

How do I read the boost guage correctly? The -7 0 +7. What is each reading? I know -7 to 0 is when I am off the throttle, but what does this mean on the guage?

One last guestion, the front torque guage, does this only usually move during hard launches? Not sure on this one either.

Thanks for any light you can shed on this.

Dave

[lachlanw]

man just search it . i fully put up a topic like a week ago about this.

+7 on that gauge equalls like exactly ten psi. (9.97666 blah blah something). rs four s models run ten pound all the way through from the factory . i also have a defi gauge in mine and it reads .7 kgf/cm which is also ten psi . front torque gauge moves anytime you get the rear wheels to break traction eg hard launches or oversteer round a corner or grass/snow

[lachlanw]

i believe the increased boost coincides with the extra ten NM of torque claimed on the rs 4 s models over everything else aswell

[jippa]

full 3 inch exhust and high flow cat made my boost go up to 11psi. nearly 12 on a cold day. oh, i have also done the grond the boost solenoid. biger turbo will also make more boost so 14 psi sound right for your mods

[lachlanw]

and ofcours having a high flowed turbo and full exhaust will give you more boost . all depends on what waste gate actuator you have . the ecu can not make it run any less boost than the pressure required to over come the waste gate spring

[SSStagea]

After reading your thread from last week, you were asking as well. No one in that thread seemed certain of it being a definite 10psi constant, only personal experiences. As for searching, I did that, hence the reason I came up with mentions to the fact that others have said the +7 is equal to around 14.7psi. Also the first reply to your post was about the fact that the NEO runs the same 5/7psi that the non-NEO runs. Hence the reason that I enquired as to how to read this guage. Thanks for your help. Anyone got a link to an english specs for the NEO motor that includes factory Boost settings?

[RS4StagMan]

After reading your thread from last week, you were asking as well. No one in that thread seemed certain of it being a definite 10psi constant, only personal experiences. As for searching, I did that, hence the reason I came up with mentions to the fact that others have said the +7 is equal to around 14.7psi. Also the first reply to your post was about the fact that the NEO runs the same 5/7psi that the non-NEO runs. Hence the reason that I enquired as to how to read this guage. Thanks for your help. Anyone got a link to an english specs for the NEO motor that includes factory Boost settings?

AutoSpeed article on the R34 Skyline (Neo Engine).

http://autospeed.com/cms/A_1832/article.html

"The powerplant is the RB25DET as introduced in the R33 GTS25T. In R34 form, however, the engine is upgraded to more environmentally friendly 'NEO' specs. The NEO RB25DET also features a hot-wire airflow meter, 9.0:1 static compression, air-to-air intercooler, ceramic turbine roller-bearing turbocharger, blow-off valve and variable inlet cam timing. With manifold boost pressure of around 60 - 70 kPa (as shown on the factory boost gauge) the R34 25GTt is listed at 206kW at 6400 and 343Nm at 3200 rpm. The R34 25GTt scores its extra power over previous models thanks to a larger turbo (providing a healthier amount of boost), better intercooler, an improved exhaust system and engine management updates."

By my calcs; 60-70 kPa= 8.7-10.2 PSI

[lachlanw]

AutoSpeed article on the R34 Skyline (Neo Engine).

http://autospeed.com/cms/A_1832/article.html

"The powerplant is the RB25DET as introduced in the R33 GTS25T. In R34 form, however, the engine is upgraded to more environmentally friendly 'NEO' specs. The NEO RB25DET also features a hot-wire airflow meter, 9.0:1 static compression, air-to-air intercooler, ceramic turbine roller-bearing turbocharger, blow-off valve and variable inlet cam timing. With manifold boost pressure of around 60 - 70 kPa (as shown on the factory boost gauge) the R34 25GTt is listed at 206kW at 6400 and 343Nm at 3200 rpm. The R34 25GTt scores its extra power over previous models thanks to a larger turbo (providing a healthier amount of boost), better intercooler, an improved exhaust system and engine management updates."

By my calcs; 60-70 kPa= 8.7-10.2 PSI

where did you get kPa from ?

[lachlanw]

sorry never mind.