Max safe boost? [Merged 10-6]

[Turbolaser]

Is it safe to do the boost contol solenoid mod on a stock 1G?

 

[zachyd23]

I have a 92 talon tsi awd with an evo 3 16g turbo. Ported o2 housing and manifold with a MBC currently running 14 psi. I'm planning on getting a FMIC, Walbro 190 or 255 fuel pump ( whichever will work best? ) , bigger injectors, ( currently running manual 450 cc's) , then getting my ECU sent out. What is an accurate psi i can run at the very most with stock internals? I would like to run 20 psi. Thanks, i'm sorry it's so long!

 

[BIRDCLAWTSi]

Look into getting a boost gauge, datalogger and a wideband, These should be your first modifications.

15 psi. is the limit for a stock fuel system(450's), It doesnt matter what turbo you have. Do some research on the best way to upgrade, if you do it the right way, You will be happy in the short run...

 

[norcal_drifter]

when i was around your setup i was running around 22psi on 91 no problem

 

[Kurptk]

I also ran 1.5bar tuned on stock internals for sometime

 

[Blue Talon Boy]

Beaten to death.

The max safe pressure you can run on stock internals is 25 PSI. I wouldn't recommend that as a daily pressure, but the engine can take it.

Birdclaw is right. The internals may be safe to 25, but a tuning solution and a fuel system to keep up with the extra air is a must. After a wideband, logger, and a tuning solution (safc at least), your next investment should be; a fuel pump (w/ rewire), AFPR, and injectors.

Sent from my Droid Incredible, because I can.

 

[1990AWD]

Beaten to death.

The max safe pressure you can run on stock internals is 25 PSI. I wouldn't recommend that as a daily pressure, but you can.

Sent from my Droid Incredible, because I can.

Tell that to Mr. Peepers who daily drives a HX-35 at 30psi on a completely stock bottom end, and many others.

 

[bryanwheat]

Beaten to death.

The max safe pressure you can run on stock internals is 25 PSI. I wouldn't recommend that as a daily pressure, but the engine can take it.

Birdclaw is right. The internals may be safe to 25, but a tuning solution and a fuel system to keep up with the extra air is a must. After a wideband, logger, and a tuning solution (safc at least), your next investment should be; a fuel pump (w/ rewire), AFPR, and injectors.

Sent from my Droid Incredible, because I can.

Psi has nothing to do with it. It's all about cfm of air being pushed into the engine. A 14b at 25 psi will make maybe 300 horsepower. An hx35 at 25 psi will probably make 450+.

 

[Blue Talon Boy]

I'd have to look at his mod list, but something tells me he is studded with a MLS HG.

The OP did not mention wanting to pull the top end. I currently run 21 PSI on a stock bottom end, with an OEM HG, and ARP studs.

Sent from my Droid Incredible, because I can.

 

[Blue Talon Boy]

Psi has nothing to do with it. It's all about cfm of air being pushed into the engine. A 14b at 25 psi will make maybe 300 horsepower. An hx35 at 25 psi will probably make 450+.

That is true. He has a e3 16g.

The stock internals can handle around 500hp properly maintained. He was asking pressure, not horsepower level. There are other things he needs to do then just raise pressure and hope for the best.

Sent from my Droid Incredible, because I can.

 

[Alex7747]

I'd have to look at his mod list, but something tells me he is studded with a MLS HG.

The OP did not mention wanting to pull the top end. I currently run 21 PSI on a stock bottom end, with an OEM HG, and ARP studs.

Sent from my Droid Incredible, because I can.

People run 30+ psi on the stock head gasket all the time.

Like stated above, its not the psi but rather the amount of air flowing thru the engine.

why do you think the fuel cuts (on a stock car, this is only an exampe. not saying the op has a stock car) out at a certain air flow level and not at a certain psi?

 

[MY1GDSM]

This ^ fyi stock ecu cuts fuel at 2.55 g/rev also this ^^^^ an that^^^^^

My motor is pretty much "stock" minus some arp headstuds..... Needless to say the first time I ran over 30psi years an years ago it didnt blow up there way more factors then boost that come into play

Op

Id be more concerned aboit how you going to get the car a tune once you do all these mods ( without that your car could end up slower) then any certain "psi" you can run thats not what makes power an the topic like stated above has been beaten to death

 

[Mr Peepers]

why do you think the fuel cuts (on a stock car, this is only an exampe. not saying the op has a stock car) out at a certain air flow level and not at a certain psi?

Because a stock car(MAF) only knows airflow, and uses that to estimate pressure.


Many, many people have run more than 30 psi on a regular basis with a stock 6 bolt bottom end. I'm almost positive that Ostar Motorsports and Mike Rizzotti were/are running high 30psi(if not 40 psi on occasion), and doing it for a long time.

I'm on a felpro composite headgasket and L19's at the moment.

My timeline:

Mid 20 psi on a composite felpro and stock head bolts started to push coolant with the evo3 16g. Also on SAFC, so excessive timing by nature.

25psi all day on standard ARP's and a felpro composite on the hx35(also used with the 16g), didn't fail until almost a year later when I upped it to 30 psi. It was already hurt from doing multiple highway pulls while going to MOD Huge boost spikes when the 16g blew off the wastegate line, lean spike when the evo8 fuel pump couldn't keep up etc.

30psi for about a year now after I slapped another composite on with L19's. Lean spike from IAT failing, boost spiking to mid-low 30 psi on cold nights etc. I wouldn't be afraid to turn it up a little more but I'm still on a 3 bar map sensor. I think the standard ARP's would have held up if the HG didn't go through so much before hand but I wanted to be done with it and not have to re-machine anything in the process.

Timing is a huge contributor as well, not just boost.

Stock internals are still a mystery to me on how far they will go. This motor has been a work horse and I have no fears about it taking a ton more abuse. Mike retired his stock shortblock but Ostar will be pushing the envelope a bit further soon

 

[Alex7747]

Because a stock car(MAF) only knows airflow, and uses that to estimate pressure.

I thought a MAF measured the flow of the air coming in the engine?..MassAirFlow.. and the MAP sensor measured the pressure?. but i could be wrong.

 

[cpoindexter]

I thought a MAF measured the flow of the air coming in the engine?..MassAirFlow.. and the MAP sensor measured the pressure?. but i could be wrong.

The MAf does in fact measure air flow, but it esimates pressure instead of having actual pressure like a MAP sensor.

 

[Alex7747]

The MAf does in fact measure air flow, but it esimates pressure instead of having actual pressure like a MAP sensor.

i didn't know this, thanks for letting me know.

 

[MY1GDSM]

Sounds like a few people are confused here... .

Our cars from the factory use a Karman vortex airflow sensor

Heres is some reading material on the principles of how it works

http://en.wikipedia.org/wiki/Mass_flow_sensor-karman_vortex_sensor

google doc pic 1

google doc pic 2

Edit

The MAf does in fact measure air flow, but it esimates pressure instead of having actual pressure like a MAP sensor.

Our Maf do infact have Barometric presure sensor but its not for measuring the engines presure/Load just the actual outside atmospheric Pressure

 

[cpoindexter]

Sounds like a few people are confused here... .

Our cars from the factory use a Karman vortex airflow sensor

Heres is some reading material on the principles of how it works

http://en.wikipedia.org/wiki/Mass_flow_sensor-karman_vortex_sensor

google doc pic 1

google doc pic 2

Edit


Our Maf do infact have Barometric presure sensor but its not for measuring the engines presure/Load just the actual outside atmospheric Pressure

Sorry, I wasn't 100% sure how the MAFs work on this car, I was using my previous experiences with MAFs.

 

[Wit]

I've heard of people running 30 psi on a stock lower end. It's the fuel system mainly that you have to worry about. Bigger fuel pump, injectors, aftermarket boost guage, wideband O2 sensor are a few to start with. If you do turn up your boost considerably it would be wise to get it properly tuned. Running too rich or too lean can cause catastrophic failure fast.

A while ago a good friend of mine had a Civic DX hatch with a B16 turbo swap. He never got it tuned or really set up fuel management. He was still fast....for a few weeks.

 

[zachyd23]

Thanks for your guy's input. I plan on getting 650 cc injectors, Walbro 255, if it works, then upgraded ECU, and FMIC. Also by the way, i have a boost gauge but no programmers or anything. To clear up the answers, after i get all of this done, I should be able to run 18-20 psi with stock internals ( head gasket and studs ) then?

 

[91stocker]

A bunch of non sense in this thread already. Psi is irrelevant. You need to leave it where its at (maybe even turn it down since you dont have a boost gauge) until you get some sort of tuner and a wideband.

 

[zachyd23]

I mentioned in my last input i have a boost gauge set up currently at 14 psi, and i'm asking these questions so i know for sure what my engine can handle without messing anything up.

 

[AlaskanDsm]

In all honesty, you are on the right path but you should get the tuning and wideband first instead of later such as ECMLink or similar and something like the LC-1 innovate wideband or the AEM. These will make sure that once you properly understand where you car should look as far as tuning and numbers go, you can do pretty much any other upgrades that you want. I bet that with a good tune now, at 14psi, you will notice a pretty good jump in HP.

 

[knewblewkorvett]

That is true. He has a e3 16g.
The stock internals can handle around 500hp properly maintained. He was asking pressure, not horsepower level. There are other things he needs to do then just raise pressure and hope for the best.

Really? I always thought 400 HP was about the max for stock. I'm hoping a EVO III 16G along with many more mods will get me at least 350HP.
So, reading this thread 30 PSI is safe? Will an EVO III 16G do that?

 

[zachyd23]

Even if 30 psi is allowed with stock internals and everything , i'm not going to go to that extent even my engine can. I don't think the Evo 3 can even handle 30 psi so I personally wouldn't try it. Im going to run 18-20 psi which will be considerably better then 14; and thats enough for me right now.

 

[Mr Peepers]

The max safe psi and/or power(they are separate) will probably be limited by the individual parts and the tuning more than the stock internals.

You will have to log for knock and check afr along the way, and the most power or boost will probably be limited by something else in your setup. Turbo efficiency and/or flow, intercooler efficiency, fuel supply, fuel octane etc.

Do some logs, pull some plugs, and go from there.