injector size and boost????

[Ginglingston11]

hey guys im looking to upgrade my entire exhaust. Exhaust manifold and o2 housing to evo III andturbo back n1 and evo III gt turbo. i have to choose what size injectors i want. And how does anyone have an idea how much boost can i drive daily with? right now i have a walbro 255 and boost contoller, stock t-25 at 22psi. thanks for the help

 

[oldman]

Damn, 22psi on T25 with the stock bov and injectors? Not only you're killing that T25, you're probably not making any more power than if you were boosting 17psi, stock injectors aside. I have some suggestions.

1. AFPR for the 255 pump.

2. 660cc injectors for EVO3, the need for fuel management goes without saying.

3. Upgrade to 1g bov prior to turbo upgrade.

4. Turn your boost down to about 16-17psi for now.

5. Properly port your manifold, turbine and o2 housing, prepare them for boost creep.

Good luck.

 

[kgtalon95]

Damn, 22psi on T25 with the stock bov and injectors? Not only you're killing that T25, you're probably not making any more power than if you were boosting 17psi, stock injectors aside. I have some suggestions.

1. AFPR for the 255 pump.

2. 660cc injectors for EVO3, the need for fuel management goes without saying.

3. Upgrade to 1g bov prior to turbo upgrade.

4. Turn your boost down to about 16-17psi for now.

5. Properly port your manifold, turbine and o2 housing, prepare them for boost creep.

Good luck.

What he said.

And for the love of all things holy turn down your boost on the t-25, you'll make the same power on a lower boost level and your internals will be much happier. Hope you don't plan on boosting your evo gt at 30 psi.............because in some ways its similar to what you're doing with your t-25

 

[2gGSX]

How so? It was modeled after the Evo III which does fine upwards of 28 lbs of boost. Although, with the much larger flapper door I doubt it'll hold that much boost anyways.

 

[Ginglingston11]

well first i do have a couple bov's, now i have the apexi bov and i just bought a 1g bov 2 weeks ago im just looking for a flange. secong i mentioned i was replacing the manifold, o2 housing, and turboback n1. now, you guys think i should go with 660s and 17 psi daily driving?

also after i replace headgasket, head studs, and hks cams 272/272 how many pounds can i run it on daily?

 

[turbo90gsx]

Your going to want to invest in some sort of fuel management rather quickly before you plan on doing much eles with the car. I would stop thinking about how many pounds of boost you can run, and start thinking about how you are going to control your fuel. And your post is just confusing. Are you upgrading to an EVO 3 turbocharger?

 

[Ginglingston11]

im upgrading my turbo to the evo 3 gt. im also getting an evo 3 exhaust manifold and o2 housing, and turboback apexi n1. my question was what size injectors should i go with and daily driving pounds so i dont over boost

 

[oldmopwater]

turn the boost down in the meantime past 18lbs the t25 is ineffecient

 

[oztofrdm]

Daily driving boost means nothing... I daily drive on a b16g at 25 psi on pump gas and dont see ONE count of knock, its all in the tuning. Once you get everything put on dont hook up the boost controller and start tuning from there. You will find out what your max boost can be.

 

[bastarddsm]

Check this out. 14psi winter time destroyed this motor BE WARNED!
http://www.dsmtuners.com/forums/showthread.php?t=125633

 

[dsm-onster]

How so? It was modeled after the Evo III which does fine upwards of 28 lbs of boost. Although, with the much larger flapper door I doubt it'll hold that much boost anyways.

No.

Here's a compressor map for the TD05HR EVO3 16G compressor. No way will 28 lbs of boost will be beneficial except MAYBE with water injection or a very poor flowing head (not characteristic of any 4g63 head).

 

[2gGSX]

http://www.dsmtuners.com/forums/showthread.php?p=1695576#post1695576

Datalog of my 118.78mph run:
http://www.dsmlink.com/forums/showthread.php?t=4834&highlight=16g

Peak airflow was 41.9lb/min.

[email protected] run:
http://www.dsmlink.com/forums/showthread.php?t=2807&highlight=16g

Peak airflow was 42.2lb/min.

In case you can't read those forums,

and boost was around 24.5psi with a spike to over 30psi.

90tsiawd from the same thread also spikes to 30+ then settles to 24. My mistake on 28 psi boost, is 24 more acceptable to you then?

 

[kgtalon95]

I was just using a metafor to describe what he was doing with his t-25............nothing else. I could have used 35......500000psi, the point was too illustrate how you gain no power running a turbo past its efficiency.

 

[Ginglingston11]

well first i got my walbro fuel pump and installed that and some how my boost increased to 20 psi. sounds strange but it happened. then i installed my boost controller and i was at 22 psi. and let me tell you it pulled like a -----.

 

[dsm-onster]

http://www.dsmtuners.com/forums/showthread.php?p=1695576#post1695576


In case you can't read those forums,
90tsiawd from the same thread also spikes to 30+ then settles to 24. My mistake on 28 psi boost, is 24 more acceptable to you then?

Yes, that's better . A PR of 2.67 (24.5psi) is hanging on to the outer limits of the efficiency island and a PR of 2.91 (28 psi) is just too far off approaching 145,000 rpms. So everyone's right. I just wouldn't want to blow up a perfectly good turbo by running it that hard all the time, is all. An EVO3 16G is capable of delivering at 24 psi.

 

[larsrya8]

well first i got my walbro fuel pump and installed that and some how my boost increased to 20 psi. sounds strange but it happened. then i installed my boost controller and i was at 22 psi. and let me tell you it pulled like a -----.

When I installed my boost controller I had it turned all the way down and my boost dropped slightly from stock. Maybe you installed your MBC incorrectly?

I have no idea why running really rich from the 255 would cause your boost to go up.

 

[Ginglingston11]

i seriously dont know why my boost would increase before i put my boost controller in. i thought my cheap boost gauge was busted so my buddy swapped for an hour and it did the same thing. and honestly how hard is it to install a mbc? like i said after i installed it i was at 22 and never changed it

 

[2gGSX]

Have you tried adjusting it to go down from 22? If it doesn't go down, perhaps you installed it backwards.

 

[oldman]

Ginglingston11, we can help you solve your boost control problem but first you must accept a couple of facts so this process will not take 3 pages.

1. You can not be running 22psi on T25 and stock injector and BOV, just because you don't feel problems doesn't mean it isn't there.

2. Although hooking up a mbc seems pretty simple, it's not as simple as you think because different brands/types of mbc requires different hook ups.

3. It's possible that you have a defective mbc.

Now that we got that out of the way, answer my question in detail and forget for now what you know or think you know.

1. What brand and type of mbc do you have?

2. Describe exactly how you have it hooked up, hose for hose.

 

[Ginglingston11]

look idk how everyone is stuck on the fact that im running on 22 pounds on my t25 stock injectors and for the last time i have a apexi bov in now and i have a 1g without a flange in my garage. but if you can read the topic of this forum was WHAT SIZE INJECTORS SHOULD I BUY WHEN I UPGRADE MY TURBO AND FULL EXHAUST? THEN MY OTHER QUESTION WAS HOW MUCH BOOST SHOULD I PUSH ON THIS TURBO? thanks for absolutely nobody answering the question i had.

 

[daren_p]

If you are running 22 psi on the t25, Im surprised that its still operating and that you havent done any damage to the motor, yet. As everyone has said 22 psi is way out of the tiny t25's effiency range and you are just blowing hot air at anymore then 16 psi. Not to mention your stock 2g bov will leak at ~12 psi so you are actually making the turbo work even harder because of this leak. This makes the air even hotter, creating knock and destroying your motor. Do you have some sort of logger so you know whats going on? When you said the evoIII is fine at 28 psi. I sure hope this is not what you are planning to run on the street (ie street tune and pump gas)

 

[oldman]

look idk how everyone is stuck on the fact that im running on 22 pounds on my t25 stock injectors and for the last time i have a apexi bov in now and i have a 1g without a flange in my garage.

How does running a apexi bov (probably vented ) change the fact that you're running 22psi on t25 and 450s?

but if you can read the topic of this forum was WHAT SIZE INJECTORS SHOULD I BUY WHEN I UPGRADE MY TURBO AND FULL EXHAUST?

Already answered.

2. 660cc injectors for EVO3, the need for fuel management goes without saying.

THEN MY OTHER QUESTION WAS HOW MUCH BOOST SHOULD I PUSH ON THIS TURBO?

Already answered as well.

Daily driving boost means nothing... I daily drive on a b16g at 25 psi on pump gas and dont see ONE count of knock, its all in the tuning. Once you get everything put on dont hook up the boost controller and start tuning from there. You will find out what your max boost can be.

i seriously dont know why my boost would increase before i put my boost controller in. i thought my cheap boost gauge was busted so my buddy swapped for an hour and it did the same thing. and honestly how hard is it to install a mbc? like i said after i installed it i was at 22 and never changed it

I took this as a question, an indication that you have no clue what you were doing, this is why myself and everyone else was trying to help you figure out what is causing your all out boost.

thanks for absolutely nobody answering the question i had. :talon

You're welcome, sorry for trying to help you out so you don't blow you turbo and motor. Now take your head out of your ass and do some search on your own as the questions you're asking has been answered many times in the past including in this very thread. What a waste of time.

 

[Denji]

http://www.roadraceengineering.com/eclfuel.htm

here is a link to road race engineerings fuel injector chooser assistant, this directly answers your initial question. Hopefully that page will have what your looking for.

 

[daren_p]

look idk how everyone is stuck on the fact that im running on 22 pounds on my t25 stock injectors and for the last time i have a apexi bov in now and i have a 1g without a flange in my garage. but if you can read the topic of this forum was WHAT SIZE INJECTORS SHOULD I BUY WHEN I UPGRADE MY TURBO AND FULL EXHAUST? THEN MY OTHER QUESTION WAS HOW MUCH BOOST SHOULD I PUSH ON THIS TURBO? thanks for absolutely nobody answering the question i had.

Everyone is stuck on this fact because there trying to help you not to blow up your turbo & motor Do you have any sort of logger? If so invest in one of these setups before you do anymore upgrades. How much boost can you run? Well there isn't a "rule" it depends on your bolt ons, your fuel, your tunning ability etc. With the PROPER supporting mods most run 18-20 psi on the 16g series on a street tune. For injectors go with 650's if you are using a piggyback fuel management system. If you are using something such as dsmlink go with 750's or larger.

Next time before you go flaming on everyone who is trying to help you, maybe you should do a search because the 2 questions you asked are probably the most common questions on this board and have been answered a thousand times before and nobody flamed on you for asking them again.