[Mooreski]

I know the stock boost topic has been beaten to death, but bear with me.....

Every topic I've found regarding stock boost says it should top out around 7-8. I'm regularly getting 10.7 psi in WOT runs in 1st, ~8.7 in 2nd (manual transmission). The only thing I've done is put on an oil catch can. The boost gauge was more for curiosity than wanting to mod (yet). I see those boost numbers in any weather, 30-80 degrees, elevation 200'-5000'.

Anyone running a stock setup with a boost gauge and seeing boost in the 10+ range? I'm on progman 32.0 (I think, maybe 32.2). It's been a while since they reprogrammed my car and I can't remember what version I got.

I'm not too worried, mostly curious what other people are seeing. Could it be the gauge? Are those real boost #'s?

[JayKay335i]

Did you calibrate the gauge?

[lpphreakx06]

Did you buy your car used?

[Mooreski]

Bought the car new, recalibrate the gauge often.

[Mooreski]

car's a late '08 if that changes anything!

[JB335]

Are you testing your wide open throttle runs after a hard downshift?

I was told, the most accurate way to test the gauge is to do a single long gear pull, with no downshifts. for instance, put it in third get on the gas without engaging a down shift. Gradually give it full throttle until it tachs out and check the boost.

[sashmanparker]

i hit around 10 psi on valet mode, i think thats just because there is a boost spike when you switch gears. Dont take my word for it though.

[Terrance28]

Its just spikes I'm pretty sure the boost don't hold there at all. If you want to check your boost do a wot run in 3rd gear.

[sfr811]

my stock boost tops at 8psi.

[Mooreski]

Thanks for the tips. I'll try a WOT in 3rd and see what I get. The boost spike idea seems plausible since I can only get the 10+ in 1st and second is usually around 8.4 psi. Seems like the real boost (neglecting spikes) would be the same in each gear!

[Former_Boosted_IS]

How are you seeing a boost spike if you are measuring at the intake manifold rather than the charge pipe T-Map?

[BoostedCosta]

I find it hard to beileve that your spiking at 10psi you must not calibrated it right. I've never seen my gauge peak over 10 lbs on valet mode

[Mooreski]

Boosted_IS, I don't really understand what you're saying. I'm measuring from the T-connector, not the intake manifold (I think). I connected based on the standard Rix instructions. I started getting into climbing and have been nerding out on that gear recently instead of my car so I forget the exact mechanics of where I connected.

Are you saying the point I connected will only give me true boost and not have any spikes?

[Mooreski]

There isn't much to calibrating the gauge. Hold the button on the front while turning your car on, but not turning the engine over. Wait until the gauge says end.

Pretty simple.

If I turn the electronics on and leave the engine off it reads a perfect 0.0 psi.

[Former_Boosted_IS]

Originally Posted by Mooreski

Boosted_IS, I don't really understand what you're saying. I'm measuring from the T-connector, not the intake manifold (I think). I connected based on the standard Rix instructions. I started getting into climbing and have been nerding out on that gear recently instead of my car so I forget the exact mechanics of where I connected.

Are you saying the point I connected will only give me true boost and not have any spikes?

Rix gauge measures boost off the intake manifold rather than the T-MAP sensor. That means boost spikes that occur when the throttle plate closes will be seen by the T-MAP, but not the Rix gauge.

[Mooreski]

Ahhhh, that makes sense. Just had to get some coffee in me (and get an explanation). Thanks for the clarification.

[alextremo]

I have seen readings on mine using the peak recall function as high as 16.7 w/Procede V3 stage 1. On 3rd gear WOT pulls, generally reads right around 14.5.

The high numbers happened only once or twice during spirited highway driving, going through a couple gears at or near WOT. I have 6AT. Anyone else see this?

[RiXst3r]

Originally Posted by JB335

Are you testing your wide open throttle runs after a hard downshift?

I was told, the most accurate way to test the gauge is to do a single long gear pull, with no downshifts. for instance, put it in third get on the gas without engaging a down shift. Gradually give it full throttle until it tachs out and check the boost.

+1

Originally Posted by sashmanparker

i hit around 10 psi on valet mode, i think thats just because there is a boost spike when you switch gears. Dont take my word for it though.

+1 totally normal

Originally Posted by Terrance28

Its just spikes I'm pretty sure the boost don't hold there at all. If you want to check your boost do a wot run in 3rd gear.

+1

Originally Posted by Former_Boosted_IS

Rix gauge measures boost off the intake manifold rather than the T-MAP sensor. That means boost spikes that occur when the throttle plate closes will be seen by the T-MAP, but not the Rix gauge.

we are not talking about throttle closure boost spikes, we are talking about ACTUAL boost spikes that the car allows to happen during shifts, kickdowns, etc... its because these snails spin up so fast, and boost can sometimes be held between shifts, they will spike for a split second... totally normal, any FAST boost gauge can see these spikes, not just mine.

[RiXst3r]

One thing you guys need to understand about this gauge is that its EXTREMELY FAST and ACCURATE... meaning that it is going to catch EVERTHING... things you wouldnt even be able to see on other gauges. This is a good thing... you want a gauge to be as fast and accurate as possible so that you can see everything that happens... your engine is seeing that boost, so should you.

btw, bmw states in the N54 documents that the engine, stock, can boost as high as 11psi

-Rick

[Mooreski]

Yeah, I'm not too worried. I'm mostly curious. I thougth the 11psi boost would be reserved for high altitude situations where thinner air needed a bit more compression. Thanks for chiming in!

[RiXst3r]

Originally Posted by Mooreski

Yeah, I'm not too worried. I'm mostly curious. I thougth the 11psi boost would be reserved for high altitude situations where thinner air needed a bit more compression. Thanks for chiming in!

No problem... I will probably make some mention of this in the instructions, so that people understand what causes spikes.

Yep, that is what 11psi is for, I just mentioned that so people see that its not hurting anything

The biggest spikes will be seen in 1st gear... especially on cars with the non-laggy progman updates (32.x?) and on 6AT cars during a kickdown from like 4th to 2nd, even then its ussually only 1.5psi This car is pretty good at controlling spikes fast

[Zeph]

Originally Posted by Mooreski

Yeah, I'm not too worried. I'm mostly curious. I thougth the 11psi boost would be reserved for high altitude situations where thinner air needed a bit more compression. Thanks for chiming in!

that is basically the purpose of SSTT is to keep the car at that "stock high altitude boost/tune setting" all the time.