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

 

[Coup D E'Tat]

PSI means jack shit. 25 PSI on a 14B and 25 PSI on a GT35R and very different.

 

[Omega]

PSI means jack shit. 25 PSI on a 14B and 25 PSI on a GT35R and very different.

Eh? your boost gauge just reads the backpressure of air that isn't able to make it into the engine. It's like which weighs more, a ton or lead or a ton of feathers.

Now if you are talking about the efficiency of the turbo, and temp of the air then yes, I agree with you.

 

[oldman]

Ryan,

It all depends on what type of supporting mods you have. The big keys in being able to make strong power on stock internals are:

1. Fuel supply
2. Ability to maintain a cool intake charge
3. Ability to minimize knock
4. Optimizing air/fuel ratios and timing

If you have a stock turbo, it doesn't pay to turn it up more than a few psi as mentioned above since the T-25 is pretty weak. Cranking the boost will contribute to it's early death. However, as you progress and formulate a game plan that encompasses all four of the elements I mentioned above, you'll be able to sustain higher and higher boost levels (to a point).

As an example, I run 20 psi on pump gas with 23 degrees of timing advance and an 11.7:1 air/fuel ratio with stock internals, head bolts and head gasket. I've run as high as 23 psi on 110 leaded race/pump gas mix and 26 psi on straight 110 with the same setup. As a general reference point, as you get closer to the magic 400 crank horsepower number, then you'll need to consider upgrading internals, although many have gone beyond this with a simple head stud and head gasket change.

Hope that helps,

Andy

This is the advice I would listen to.

 

[alexsmede]

sorry guys, i was assuming this was on the stock turbo.

 

[cky]

Thanks guys for all the great positive info. The gst is currently running 13 psi only mods to the motor is bov,boost gauge,injen intake,3 inch dp w/ hks full exhaust and Manuel boost controller. Does anyone know the hp numbers at certain boost levels? I should probally read the newbie section and tech section before i ask but just curious if anyone has any info. Thanks in advanced for everyones help.


-Ryan

 

[fwdturbobov1996]

Buddys fp red gsx is running 29 with alcohol injection. Stock 2g block, 1g head, and 264/272's

 

[BGRIPTP]

Freind has ran 28psi on a 60-1 stock motor/head. Put down 496whp.

 

[90tsisicko]

Eh? your boost gauge just reads the backpressure of air that isn't able to make it into the engine. It's like which weighs more, a ton or lead or a ton of feathers.

Now if you are talking about the efficiency of the turbo, and temp of the air then yes, I agree with you.

That is not true....each turbo has a different cfm....a smaller turbo has a samll amount of cfm and a bigger turbo has a bigger cfm.....ex a t25 @ 15lbs is not going to make as much power as say a gt35r @15lbs with the same mods...

 

[oldman]

That is not true....each turbo has a different cfm....a smaller turbo has a samll amount of cfm and a bigger turbo has a bigger cfm.....ex a t25 @ 15lbs is not going to make as much power as say a gt35r @15lbs with the same mods...

cfm is a measure of the turbo's maximum output, nothing to do with both running at 10psi. 10psi is 10psi, the only difference is the intake temperature due to turbo efficiency, the cooler the more dense the air the more oxygen. T25 however will still have the quicker spool of the two.

 

[90tsisicko]

i was under the impression that a bigger turbo will make more power at an XX lbs that a smaller turbo at the same boost.....correct me if I'm wrong!!

 

[oldman]

i was under the impression that a bigger turbo will make more power at an XX lbs that a smaller turbo at the same boost.....correct me if I'm wrong!!

You're correct but that difference is caused by the intake temperature and was mentioned in Omega's original post so your statement about him being wrong and that cfm is waht makes the difference were wrong.

Eh? your boost gauge just reads the backpressure of air that isn't able to make it into the engine. It's like which weighs more, a ton or lead or a ton of feathers.

Now if you are talking about the efficiency of the turbo, and temp of the air then yes, I agree with you.

 

[90tsisicko]

thank you for pointing that out.....i am now an official dumba**

 

[assa 98gsx]

I think it all is depend on individual cases. I have friends blew the motor at 15psi with all the supporting mods and i am running 20psi on the track without blowing the motor just yet. Every motor is built with slight deviations and thus you can really apply simple equations on it. You need to try it out yourself, start from low psi and work upwards. If things do blow, then good luck and rebuild the motor to run the desired boost level. If you want to play safe, leave it stock. If not, prepare for the worst.

 

[oldman]

thank you for pointing that out.....i am now an official dumba**

I think you will do well.

 

[cky]

I think it all is depend on individual cases. I have friends blew the motor at 15psi with all the supporting mods and i am running 20psi on the track without blowing the motor just yet. Every motor is built with slight deviations and thus you can really apply simple equations on it. You need to try it out yourself, start from low psi and work upwards. If things do blow, then good luck and rebuild the motor to run the desired boost level. If you want to play safe, leave it stock. If not, prepare for the worst.

thanks for the advice the thing is i dont want to play around with it to much and overboost it and blow my motor

 

[Deadly BlaZe]

i read the tech guide but it doesn't really specify things for me. my car is basically stock with just a K&N air filter and an aftermarket muffler. i was wondering if i could raise my boost to about 14 psi safely without having things like an exhaust or fuel pump?

 

[Pure92TSi]

Yes you can but that should be the absolute highest you go and i would suggest only goin to 12 until you free things up and make sure you are getting enough fuel and not getting a bunch of knock. If you have a logger that would be a big help.

 

[larsenracing]

yor stock ecu can handle a feew psi but to raise your boost you will need a boost controller so you will be just fine raising to 14psi. but good luck.

 

[Spookcorleone]

Yeah I run 14 - 15 PSI all day everyday, and the car is fine. Make sure you have boost gauge / controller. Getting a full exhaust system would add a good bita pep to'er step.

 

[Corpssnare]

You might need an aftermarket BOV, too. I know the 2g BOV will leak after 12-13 psi, I dunno about the 1g, but I'd imagine it's not too different.

 

[xveganxcowboyx]

The 1G BOV holds better than the 2G. Not sure on what PSI crushed and uncrushed, but I think 14 on a stock 1G would be fine.

 

[Mist3r Spool]

I have a 2G and they do leak quite easily. As soon as I installed my first BOV, which was an HKS SSQV, the boost increased about 4-6 PSI since the stock one was always leaking. You have a 1G and I believe those ones leak as well, but not as bad. Most people who have been around the DSM block seem to prefer a "crushed" 1G BOV since it holds up exceptionally well even with higher boost levels. Anyway to answer your question, YES you can boost to about 15-17PSI with your 14B and have no problems at all-having an intake+exhaust helps.

 

[Ultimatedsm]

1g BOV can hold 17 psi no problem a crushed 1g BOV can hold over 20 psi. Anyway with the stock fuel system you should no exceed 16 psi. I would rewire the pump for now to push extra fuel out. Depending on your horsepower goals I would either get a Walbro 190 LPH or a 255LPH with an after market fuel pressure regulator.

With any of these pumps you can safely boost 17 psi with stock injectors on a 14B turbo. You will notice a great power increase as well.

 

[CHnKTSi]

i would say 1g crushed will be safe until 18psi. i run mine to 16 daily drive, going to school and weekend track racing.
But when you do decide to boost, get things done right the first time and get the parts NEW.
I used the boost controller and the gauge that has been sitting in my other tsi (that's been sitting in front of my house for 6 years now) and the boost controller was messed up (somehow). the controller fell apart and boost creeped over 20psi, causing blown head gasket as well as fuel pump failure and this and that.

 

[Deadly BlaZe]

I think only one of you have actually answered the question. I only want about 14 psi, not 243524 psi. I know my 1g bov will hold 14 psi. I'm just asking if there are any other necessary supporting mods for raising it to 14 psi.