Max safe boost? [Merged 10-6]

[Turbolaser]

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

 

[14.5 drift]

Theres actually a way to trick your ecu so you can run a bigger injector without fuel control, some one might be able to give some more info on that, sorry I can't be of more help on this, but.......




I do know you are not supposed to add more boost to lean out the mix. The more boost you add, the more fuel the ecu will add to the mix, so you won't be changing the mix at all until your injectors actually run out of fuel. All in all, very bad idea..

 

[Gigaah]

The sig picture of your car looks super sick! I was very disappointed to see your gallery and see that it was an edited picture. Thats godda be the first picture of a 92-94 front end that made me think I might want a 92-94. I like the talon logo but the lights are waht did it.

 

[BMWHATR]

I have a t-25 turbo (stock) and i wan to turn the boost from 11psi to 14-15 pis i was just wandering what els do i need to do. do i need to change any parts? will it be safe?

 

[DSMhelex]

you should be fine at those boost levels... i ran my old t-25 at 14psi. make sure your using a good boost controller and you dont spike any higher than that.

 

[DSMvroom]

well you're obviously going to need to start with some sort of boost control, a gauge, and maybe a new cbv. Other than that I think it should be ok up to 16psi if you can get it there.

However, the consensus is to do your upgrades as per the upgrade guide; but that is just a guide and you can ultimately do it however way you want.

 

[SnowWhite]

I run 15 lbs on my t-25 and it is fine until you hit about 6500 rpm's and the turbo falls off the map.

 

[BMWHATR]

Not good i need some kind of point that i can go all the way to 7,000RPM's without have to worry about turbo. but still don't know if 14PSI will kill my turbo life

 

[fat pat]

your car will definatly be able to handle 14 psi on a t-25, your not pushing that much air with the t-25. get a good boost gauge and a controller, youll be absolutely fine

 

[tigerstalon]

Not good i need some kind of point that i can go all the way to 7,000RPM's without have to worry about turbo. but still don't know if 14PSI will kill my turbo life

I don't think the T-25 can even hold stock boost (~12psi) all the way to redline. Many people, including myself, have upped it to 14 or 15psi and have been fine. Just make sure you have a boost controller, boost gauge, and some sort of BOV upgrade. The stock 2G BOV will leak around stock boost levels, which means you will work the T-25 even harder to get to 14 or 15psi. I suggest an upper intercooler pipe upgrade that is flanged for a 1G BOV and get a 1G BOV somewhere, new or used.

 

[BMWHATR]

Do you guys know where i can get some used piping for cheap? this saturday i will be teplacing the turbo with new t-25(blew the last one and it was under warranty) alos puttin in boost gauge boost controler turbo timer blow off valve and oil gauge. do you guys think is possible to do in 6 hours?

 

[Generation1JeY]

Ok i have all the stage 1 mods done, and my next part will be a walbro 190 fuel pump. Right now my boost is set on 15 psi, i'm just wondering after the fuel pump is it safe to increase it passed 16 or would that just max out my injectors and wiring system and what not?

Do u increase ur boost over 16 psi after ur injectors? or will the stock 450s be able to hold say 17 or 18 with an upgraded fuel pump?

 

[Generation1JeY]

Ok i have all the stage 1 mods done, and my next part will be a walbro 190 fuel pump. Right now my boost is set on 15 psi, i'm just wondering after the fuel pump is it safe to increase it passed 16 or would that just max out my injectors and wiring system and what not?

Do u increase ur boost over 16 psi after ur injectors? or will the stock 450s be able to hold say 17 or 18 with an upgraded fuel pump?

 

[1993eclipseGS]

I heard you can run 16psi once you get a fuel pump. But before I got all of my parts I was at 15-16psi, I may have been pushing my luck. You should get a datalogger before you turn the boost up anymore.

 

[tigerstalon]

Agreed. You can't just crank up the boost time and time again. You really need some sort of feedback as to how the car is running. A logger for a 1G will be able to tell you whether you are knocking or not, which would basically tell you that you're running too much boost. The 450's are basically maxed out around 15-16psi on stock fuel pressure level. A fuel pump upgrade is really a part of an injector/turbo upgrade. By itself, it will not give you much improvement, but it is essential to supply more fuel for larger injectors, which are only needed if you're upgrading to a larger turbo.

 

[burldude]

91 0ctane and Boost equals 15 psi . I have stage one and two done and on 91 octane the best that I can push on 91 is 15 psi . Higher than that and I get knock :thumbdown
I do not have timing turned down though and I have a stage 3 chip so octane reset is in affect. Meaning my knock sum does not pull timing if it continues to see knock . It retards it and then resets and just retards again if knock is detected . It does not increase the amount of timing pulled progressively as the stock ecu.

 

[SpoolnTsi]

Im assuming your running the 14b. I have seen people run 18lbs no problem, but every car is different and there are alot of factors that come into play. Only a logger can tell you how far you can push it. I myself have run 18lbs on a s16g and stock injectors with no knock. That was on Sunoco 94 octane also which plays a big part

 

[kaslasma]

There is no set "if you do this you can then do that"; the larger fuel pump will allow adequate fuel to be supplied in higher boost levels. If you had a fuel pressure regulator and changed your base pressure then you may be able to increase the boost slightly. Increasing the base pressure will change the amount of fuel put out of the injector, but thats not to say you can take a regulator crank it way up and have something equivalent to 720s. After part installations just log again, watch the numbers they will tell you if you can up the boost.

 

[Generation1JeY]

ok i undertand that, but what i'm asking is what is the set back on the fuel system? is it the fuel injectors that cant supply fuel after 16 psi? or is it the fuel pump?

Simple question no need to try and preach to me about set ammounts, i know every car is different and tuning is necessary after 16 psi and all that, just help me out on the fuel system.

What is the weakest link in the system?

 

[Sotarts]

Both, fuel injectors and the stock fuel pump are the weak link.

Next, you need bigger injectors and something to control them with. You shouldn't go past 16 psi at this time.

 

[headrec*]

Bigger injectors can be overrated. People in Utah run 12's with 450's. Hell one guy just ran a 11.6 with a slowboy gt-14 and 550's.

 

[kaslasma]

Ok cool, not trying to argue. I'm sorry. To answer your question the stock fuel pump will begin to not supply enough fuel to the rails. So even with a larger set of injectors they would just bleed the system dry. However, you can hardwire your fuel pump to get an extra 30 Ltr/Hr or so and that will buy you time to save money for a bigger fuel pump. headrec* is correct people have put down good traps with smaller injectors, however, your timing isn't as agressive due to the high Pulse Width / Duty Cycle. They say that its good to keep your injectors <80% DC. Once you have your fuel mods I still wouldn't go above 17 lbs because you'll be heat soaking the intercooler quickly. What I'd do is hardwire the fuel pump <$30> (<a href="http://www.plymouthlaser.com/rewire.htm">instructions here</a>), Get a fuel controller (S-AFC or MAFT, i'd get the MAFT and cut your UICP and place it there, that then lets you vent your BOV without running rich, quicker spool, and you can tune in 2% increments.), then a set of injectors (550s or 660s depending on your goals), then a bigger fuel pump (<a href="http://www.roadraceengineering.com/fuelpumpflowrates.htm">RRE's Flow Rate Chart</a> Many people have success with the 190s and 255, I run the Supra and haven't had a problem yet) and regulator (I run the <a href="http://www.fullthrottlespeed.com/">Full Throttle Speed</a> regulator and dont have a problem part # 0011GREG, make sure you either make or buy a gauge for it), then get your intercooler and should be able to rock just fine for higher boost on the 14b or even a bigger turbo.

Again sorry, wasn't trying to preach. Oh also you def need a logger. You can use that to tell you when its safe to turn up the boost. I run the TMO logger because I already had a laptop and didn't want to buy a palm. Lots of other people run palms and love those. Just need something so you can watch knock counts and timing advance. If you have the money the Innovative Wideband isn't a bad price and would be the best method to tune by. I would still have a logger to check CELs and watch other sensors. Hope this helps and happy tuning

 

[Boosted19]

you can run 11's on 450's if you do it right. i ran 21 psi on stock injectors with a big16g and no problems. on 94 oct. and 18 psi on 93 oct.

 

[Boosted19]

and i had a 190 pump.

 

[kaslasma]

What was your duty cycle on that 11 second run? How many counts of knock? What was your timing at? What was your base fuel pressure set at? Did you ever try swapping in a larger injector, retuning and running again with the only difference being the injector size?

 

[Generation1JeY]

alright thx everyone i really appreciate all the posts.

Having that be said i just want to tell u that as of right now all i am trying to do is turn my boost up, now i will tell u what i know so far on what i would have to do before going above 16 psi, if there is something u would like to add that would help me understand something better than thats greatly appreciated cause i am a pretty amatuer tuner, if i'm right on the money though then just tell me i am so i can carry out my plan pretty soon.

Ok so with the current mods i have, if i wanted to go over 16 psi i would have to:

-Get an upgraded intercooler because my sidemount would just heat soak
-Get an upgraded fuel pump
-And get a datalogger to moniter system performance

Just to let u know i'm looking for almost the absolute cheapest way to accomplish this, i'm buying my 190 fuel pump right now so thats taken care of, but also are u guys saying that i dont have to upgrade my injectors by going over 16 psi? I live in cali so with present conditions the highest gas i can get is 91 unless i really want race gas.

So as far as i know the weakest link right now is the fuel pump and my sidemount intercooler, so after i upgrade those i will be able to turn up the boost, but for precaution i need to get a datalogger, thats fine because i wanted to get one of those soon anyways to moniter how my engine is doing, whether i turn up the boost or not.

So ya just give me suggestions on how exactly i can get over 16 psi safetly with a datalogger, will the FMIC and the 190 be enough?

Thx