keep in mind you can get more boost by choking down your exhaust, but less power. You can get less boost by more efficiently cooling your charge, but more power. If you open your exhaust (the entire exhaust path) you will get less boost, but be flowing more air and might need more fuel to take advantage, thereby getting more power.

 

MSFITOY, I am in Florida... so roughly 50 feet above sea level... maybe. Should mean higher boost due to denser air, I just don't see it. I do have a Milltek cat-back and Pilo intake with cheese-holed firewall barrier.

_________________

 

Just to add one more combination to the mix.

JCW, Alta intake, Milltek header into JCW exhaust - 19% pulley.
18 lbs - 71 deg light rain, DSC & AC on.
19+ lbs - 72 deg no rain, but humid, did not hit redline

All measurements were from an Autometer elecrtonic gauge attached to the nipple for the fuel pressure regulator.

Regards,
Boris

 

The most I've seen is just a tad over 16lbs at redline.
19%
HAI
Supersprint header
M'flow exhaust
stock IC

 

well sid your 17" wheels onley whaigh about 12 pounds and i think that has an effect on the dino not much but it certanley help the numbers from what ive heard!!!

so the wheels and the header could help but i also dont see it equaling 15hp
but i think by the time ryan puts a bigger ic and header then we get to see the difference maby you just have a better combo and things are reading better with you car than with ryans!!:smile:

 

15% alta, NRP exhaust, Madness intake, Autometer Gauges, Perrin Oil Catch Can. Getting around 14-15 psi.

 

Good question Msfitoy!

Yes, according to my mechanical Auto Meter Ultra Lite 2 1/16" vac/boost (20PSI metered limit). my 15% read 19 PSI @ 7200 RPM. Yes I agree it sounds unnaturally high. No I haven't had a chance to datalog and record the MAP sensor

For comparison, my completely bone-stock setup yielded 12.5 PSI at 7000 RPM, which is markedly more than the 11.5? PSI advertised. To proportion that theoretical error, a calculated 17.5 PSI corrected @ 7200 RPM with 15% (all hypothetical) I'll report back when I get a chance to record with my datalogger.

Cheers,
Ryan

 

Alta CAI, 15%, air diverter, magnaflow, unichip, and the m7 device and I have seen a max of about 15-16 PSI... However I think the gauge is off by 1 PSI because when the car is OFF it reads 1 PSI. It is an Autometer mechanical 2 1/16 gauge.

 

Update: Now seeing 16-17psi near redline. (Autometer mech. gauge to 30psi).
2003 MCS, Alta -15% pulley, Intake, WM throttle body, Evotech, Magnaflow.

 

You guys are forgetting something... what belts (lengths and brands) are you using? If people are having mild slippage that is going to cut down on boost vs someone who's belt isn't slipping.

Patrick

 

All MINI track day at Texas World Speedway next weekend, 7/24 7/25, lookout I'm comin' ta get ya!
BTW, drivers school this weekend, maybe there's hope!

 

Your Header and Borla Race combo is much more free-flowing than his Miltek cat-back. So you're going to lose boost b/c of that (but gain power). I'd be surprised if the Miltek cat-back was very free-flowing to begin with since it is so quiet.

The highest I've seen with 19%, Madness intake and UUC exhaust is 16.5 psi. I don't push it to redline often though and I haven't had the gauges in any weather below the low 70's. The UUC gurgles constantly I'm sure it's very free-flowing and loses considerable boost over the stock exhaust.

 

mods done include alta intake, scorpion exhaust, and denso plugs, with alta 15%... best reading i got was slightly below 1.0 bar... which is close to 14.5 psi i believe

 

Stock pulley, intake and exhaust, boost reads just over 10psi at the top end.

Mods to come: 15% pulley, Alta or homebrew intake, Milltek exhaust, UNIchip.

 

BMP inake, Alta 15% pully, milltek catback, on my autometer boost gauge, I'm getting aroung 15 LBS of boost.

 

can i restart this thread oooops to late

Ok i fitted my boost gauge today, prob is its only pulling 5psi boost on full throttle !!!

Its a standard MCS with a BMP induction kit and the VGS system, but ive noticed when i turn the engine off the needle sticks at just below vacuum 10 psi and doesnt reset to 0 ! Only resets to zero when i disconnect the vacuum pipe off the rear ! and ideas ?

 

Stock pully seeing 11 psi at redline, with Alta CAI and B&B tri flow exhuast.

 

With Alta intake, VGS, NRP exhaust, with one resonator removed, and the stock pulley I am seeing just over 12 psi of boost on a autometer light gauge. I am going to the pulley party at the dragon and will report back with my findings with a 15% pulley.

 

If your looking at a guage that is not an absolute gauge then wouldn't it read the same as you guys at sea level?

Brad

 

19% miltek header&cat-back alta intake, 380 injectors, denso22:s

gaic flash,alta intercoler showing 17# @redline in 2nd.gear
steward-warner mech. 25#guage. temp.72
humidinty 40% sea level
doug

 

would like to add- car had been run aprox. 20 miles before boost test

 

...so more boost doesn't mean more power and cooler air make more power?

 

Updates:

With Alta 15% and JCW intake added but with stock exhaust, I saw just shy of 16psi as my highest reading captured consistently by the peak hold feature of my boost gauge. Upon adding a Milltek catback, the boost pressured dropped by about a half psi I am assuming from a reduction in backpressure. Car has more 'legs' above 4 grand than with stock exhaust, everything else being equal.

 

Hi guys...

I been following this thread with some amusement

As we do test a lot of cars and setups, I do have a fair amount of experience
with boost pressures at different states of tune.

I use professional boost gauge that allows me to adjust for elevation and
temperatures ie. the gauge is always adjusted to absolute zero.

With that said it does astound me to hear people getting 16-17 psi of boost
from a 15% pulley..... The highest we ever seen from the 15% is 13.8 psi.

So what's going on....wishfull thinking, my numbers are bigger then yours
or are ther more crappy boost gauges out there then not.

peter
Team M7

 

well no one commented on what could be wrong with my gauge , so found out the problem and now im reading 9 psi...is that about right for stock with a BMP filter ?