Stock Boost [Merged 5-7]

[Gs-tHaVoC]

hehe kinda dumb question but whats stock boost on my car? just wondering if its worth it to install a boost controller and gauge without bov thats all. thanx

 

[Laser-man]

yes my laser has leather

 

[allwheelTSI]

Originally posted by Laser-man
yes my laser has leather

sweet deal,where'd you get yours?

 

[boosted5speed]

Hi, whats up, i think this is my first post on DSMtuners, so sorry if it is something that gets asked constantly (i couldnt find much about it, when i search for stock boost i get 10000000 posts that dont have anything to do with the subject)

Basically, here is the story. 1990 laser RS turbo. Only mods so far = Gutted cat, free maf mods, k&n, hacked airbox. Autometer phantom boost gauge says the max boost my car ever pushes = 8 psi, which seems to concur with what the stock gauge indicates. What im wondering is, is this the correct lvl of boost i should be getting with mostly stock car? i always figured in the way of 10-12 psi on a stock 1g.

If its not hitting stock boost levels, what could be causing me to lose boost? any suggestions would be appreciated. Im going to try turning up the boost with a MBC and see if setting it higher has any effect on my overall performance/boost lvls, but I was under the impression that if im not hitting stock boost with stock equipment something is wrong.

My old 90 laser rs i had before indicated it was running closer to 13-14psi on the stock gauge, with a 3" exhaust, k&n and similar mods, and it felt considerably quicker. Will knock sensor timing retard appear to lower the max boost level im building to?

sorry for the long post, im just stumped at the moment. Is there any simple check I can do to see if im losing boost somewhere?

 

[Coldandafraid]

you could see if your BCS is closed, therefore not bleeding off some wastegate pressure, and in turn producing less boost.

Yes, knock/timing retard will fire the BCS

 

[xcelr8n]

maybe IC piping, but you should be around 12 psi.

 

[boosted5speed]

How would you go about checking to see if the solenoid is closed? ive looked at it before thinking about modifying it to make more stock boost (before I checked and realized how low my stock boost actually was) and there didnt really seem to be much i could do to it.

Is that solenoid really necessary for normal operation as long as your watching whats going on? I would assume the wastegate should open at a predetermined setting anyway even if the BCS isnt operating (or does it trigger off a problem in the ecu if you have it disconnected or bypassed)

 

[Coldandafraid]

the solenoid should normally be open. This way it bleeds off some pressure so that it takes MORE pressure to open the wastegate. So, if there is too much knock, the solenoid closes and the wastegate opens sooner.

However, if you are putting on a MBC, then the BCS no longer concerns you. Have you put it on yet?

 

[boosted5speed]

No I still need to "construct" one , I was going for a fairly simple home depot style MBC.

http://www.geocities.com/chmwatson/FAQs/mbc.html

This one seemed fairly straightforward, I was going to pick up all the pieces to assemble it tomorrow and see how things work out.

So if I blow on one of the ports of the bcs it should be bleeding boost out to make the wastegate assume less boost is present than actually is? What is the stock wastegate set to bleed off at normally, 8 psi?

Maybe my BCS is simply malfunctioning and not bothering to bleed off pressure so the wastegate is opening early =\

 

[laserturbo91]

i know how you feel, try replacing to hoses from the intake pipe to the BCS, from the BCS to the wastegate. and the others in the area, worked for me
jeff

 

[bosljeff]

Yeah, I finally got a boost gauge and I'm "stock" too and I am running 12 psi. Something is wrong. Get it fixed before you start upping the psi so you know you are at a solid baseline.

 

[boosted5speed]

Ok, MBC installed... Guess what... 9 psi
BCS is removed, it wont build more than 9psi even with the wastegate basically disconnected (what i mean is even with the boost controller set to full bleed (and i can hear the air bleeding off) the most boost ive seen out of it is maybe 9 1/2 pounds on a long 3rd gear pull from 45-90. AHHHHHHH any suggestions, bad wastegate spring or something? =\

 

[Eliminat0r]

it sound slike you need to rebuild your turbo or find someone who wiull sell you one cheap

 

[Coldandafraid]

With MBCs its the opposite of the BCS. WIth the BCS you want the air to bleed out, with the MBC you want the air to have a hard time getting through, so you screw IN the dial to make the air passageway inside smaller.

 

[jbillakdsm]

Yeah, on the MBC, screwing the bolt in more will increase your pressure. I had a similar problem with my car, I was only getting 9 psi in the stock setting with the restrictor pulled from the BCS. Even after I put a MBC on, I had trouble hitting desired boost levels. I tore the entire front end off my motor and found out I had some nice cracks in the exhaust housing of my turbo that was causing me the problems. I got another cracked exhaust housing for 30 bucks and got it welded and installed it. Now my car boosts like its brand new.

 

[bluebomber]

Check you wastegate actuator see if its getting vaccum or opening and closing. Chance's are its just wide open and thats why u can only boost at 8psi. the actuator is that golden rod connected to the wastegate next to the turbo

 

[Laser-man]

try removing your exaust and see what happened, i had the same problem and it was the exaust.

 

[Mr.Tao]

I installed Boost Gauge and Manual Controller. I tapped the gauge up to the line that goes straight to the intake manifold. THis line is right under the Fuel Pressure Solenoid. With this setup my aftermarket boost gauge reads 9 PSI. My stock gauge reading was around that same number, right above 7. I heard that stock boost reading is supposed to be around 12. So i want to know, what is the real reading? ANyHelp is appreciated.

 

[805eclipse]

im not sure what the stock reading is suppost to be, but im reading between 10 and 11..

 

[blaster1812]

I think it is supposed to be 12-14

 

[OneSexyDSM]

9-10 PSI, make sure when your checking on this stuff your boosting in 3rd because 1st and 2nd wont always get full boost.

 

[BIG JOE]

That's what the stock boost should be, correct??

thanks

bjoe

 

[Jason84]

blah.. i love 2nd and 3rd on my car (tottaly stock till today )

but yeah first is a lil weak on the boost. i hit second and its gone and same with 3rd.. but i havent really raced above 50 yet so i havent experinced 3rd to much

 

[2FastTSiAWD]

I thought it was supposed to run a little higher, and when I put on my gauge it read 8.5-9lbs. This is ok right? I ve heard some people say that 10-12 is stock, but I ve also heard that 8-9 is stock. Which is it?

 

[NoRiceTSi]

I'm right at about 10-11 on my stock gauge, the bcs mod did nothing for me, unless i was at like 8-9 beforehand

 

[Blam]

I jsut installed a automeer boost guage and my car is completely stock. what should it read?

I get 8-9 Psi at about 5000 rpms (I let throttle off at 5000)
and vacuum reads 16 at idle and 20-22 when in gear and I let off the throttle

does that sound right? or is my boost reading a little low?