fuel pump and injectors question

[RayBan GST]

hi all,

simple question maybe it was answered before, i have been away from the DSM cars since a year now and now i need to be back,

the car is running 16 PSI now on the stock t25 on stock fuel system and not even a rewired fuel pump , on 3rd and on 4th gear the car is really slow because i beleive its pulling the timming and its lean since sometimes its boosting around 18-19 PSI on 3rd or on 4th just spikiing

quesiton will this go away and the car will be back to normal with just a rewired pump? once the car reaches 18 psi you will really feel like its backing and its cutting until the boost goes back to 15 psi.

will the stock injectors handle 18 psi ?

i know the t25 will not give any power after 16 psi but please answer my above quesitons if you can

 

[dsmvenge]

I hit fuel cut at 16psi with a 190 fp and stock injectors with a E316g

 

[olddsmer]

Mine did same thing with EIII 16g. Upgraded to wally255 and afpr.Turned fuel pressure to 40 psi and can run 18psi boost with no problem. Anything above that you will need bigger injectors.


Regards
Greg

 

[RobAnd34]

Upgrade you injectors nothing crazy big cause your not running a big turbo and get a decent problem and make sure once that is done your not running to rich but you should be ok and that should fix your problem.

 

[re-rx7]

I would say yes the injectors will handle that but, then again every car is different. If you do end up upgrading injectors you can pick some up offa evo for around a $100 off the classifieds on here.

 

[99ECLIPSEGSXDSM]

Like said every car is different buti would never turn the boost up past 15 psi unless you have a way to log or watch your etgs! I say turn it down so you dont mess something up untill you have the proper upgrades to run that much psi!

 

[mitch rich]

My car could run 16 psi without feeling like that. Then with the desire every little bitt helps. I forgotten he numbers of how much more fuel it flows with just the rewire but it's a worth while thing and should help atleast a little. The t25 ###### shouldn't run 18 though. I ran
Mine at that for like 2 weeks and it went. Hope this helped

 

[hereitcomes]

Fuel cut doesn't feel like a loss of power, it feels like slamming into a brick wall.
Many, many cars both 1g and 2g's alike have run 15 psi on the stock fuel system. If you are experiencing problems, I suggest that you invest in some sort of logging device (palm, laptop or other) and post up a log of when this happens so a REAL diagnosis can be made and appropriate help can be given.

Also, bigger injectors require alternate options to have them controlled. The 2g MAF can compensate for a little, but anything bigger than 550 or even 560 (EVO 8) will need to have some sort of control like a SAFC or DSMlink/ECMlink.

Good luck!

 

[rdejardin777]

stock fuel system is good for 16psi boost max...rewired is good for 18psi on stock fuel pump...this is on a 14b though...a t25 flwos less air per psi i believe but wouldnt be too far off from the same numbers.

 

[gofer]

Believe it or not, because the 2g runs a higher base fuel pressure than a 1g, its capable of supporting a bit more airflow before hitting fuel cut. Which is funny since the turbo Mitsubishi put on the 2g, the t25, can't flow nearly is much a 14b.

The t25 is rated at 330cfm (23lbs/min), if you've got a properly working fuel system and have a way to tune your DSM, it can't max the stock 450's on pump gas.

The loss of power you're describing could be caused by a few things, it doesn't sound like fuel cut though. Give your DSM a good BLT and pull the spark plugs and check the gap on them, .028" is the FSM's recommendation. Its also possible that, with the increase in boost, you're hitting a more conservative load cell in the stock 2g fuel/timing tables which will richen things up and retard the timing.

Invest in a WB o2 sensor, without it we're all just shooting in the dark.

 

[RayBan GST]

thank you all so if i rewire it will fix my problem? Thx

 

[gofer]

Read my above post, lack of fuel is not the problem if your fuel system is working as good as stock.

 

[Bud92gsx]

Believe it or not, because the 2g runs a higher base fuel pressure than a 1g, its capable of supporting a bit more airflow before hitting fuel cut. Which is funny since the turbo Mitsubishi put on the 2g, the t25, can't flow nearly is much a 14b.

The t25 is rated at 330cfm (23lbs/min), if you've got a properly working fuel system and have a way to tune your DSM, it can't max the stock 450's on pump gas.

I second what he said...+2 Corey..

 

[RayBan GST]

so its not a fuel problem what iam having? Until 15 psi my car is pulling great only after that it starts to back up and it feels slow' , what is it now do you think?

 

[Bud92gsx]

Your using a t25.....

Could be multiple things..A boost leak test always helps pinpoint boost pressure loss...

Where do you get 98 octane..Maybe your using E20..

 

[RayBan GST]

i forgot to mention iam using 98 octane fuel only,if it makes any difference

 

[gofer]

Apparently you didn't listen (read) because I said a number of things it could be in my first post.

The loss of power you're describing could be caused by a few things, it doesn't sound like fuel cut though. Give your DSM a good BLT and pull the spark plugs and check the gap on them, .028" is the FSM's recommendation. Its also possible that, with the increase in boost, you're hitting a more conservative load cell in the stock 2g fuel/timing tables which will richen things up and retard the timing.

Invest in a WB o2 sensor, without it we're all just shooting in the dark.

If you want to believe all you need to do is rewire the fuel pump then go for it, no ones stopping you. Don't post on here asking for help then argue with the help, if your certain of what it is thats causing it then rewire your fuel pump.

 

[RayBan GST]

i am in dubai and thats why i have 98 octane, i am not new in the dsm world this is my 4th eclipse and i have done ofcourse a boost leak test and all ok, just this started to happen last week because now we have a cold and nice weather, i really want to know what is this problem

Apparently you didn't listen (read) because I said a number of things it could be in my first post.

If you want to believe all you need to do is rewire the fuel pump then go for it, no ones stopping you. Don't post on here asking for help then argue with the help, if your certain of what it is thats causing it then rewire your fuel pump.

iam not arrguing my friend, but i have seen serious damage before from the t25 , and all because of the lean situation. i saw holes in pistons before from this t25. I really dont want this to happen to my new car

 

[gofer]

Great. Have you done a BLT since it started happening? I did a BLT test a few weeks ago too, doesn't mean my car doesn't have any today especially if you start noticing a problem and you changed nothing in your setup.

 

[RayBan GST]

Apparently you didn't listen (read) because I said a number of things it could be in my first post.

If you want to believe all you need to do is rewire the fuel pump then go for it, no ones stopping you. Don't post on here asking for help then argue with the help, if your certain of what it is thats causing it then rewire your fuel pump.

iam not arrguing my friend, but i have seen serious damage before from the t25 , and all because of the lean situation. i saw holes in pistons before from this t25. I really dont want this to happen to my new car

 

[gofer]

I'm giving you numbers showing you why thats not possible with a properly working fuel system and a good conservative tune.

t25
330cfm or 23lbs/min

450cc injectors
@ 100% IDC will support 32.30lbs/min. @ 80% IDC will support 25.84lbs/min

stock 2g fuel pump (not rewired)
(boost = supported airflow)
10psi = 33.29lbs/min
11psi = 32.61lbs/min
12psi = 31.90lbs/min
13psi = 31.17lbs/min
14psi = 30.41lbs/min
15psi = 29.63lbs/min
16psi = 28.84lbs/min
17psi = 28.01lbs/min
18psi = 27.16lbs/min
19psi = 26.28lbs/min
20psi = 25.38lbs/min
21psi = 24.46lbs/min
22psi = 23.51lbs/min
23psi = 22.54lbs/min
24psi = 21.54lbs/min
25psi = 20.52lbs/min

The stock 450's maxed out will support 32lbs/min and the stock fuel pump at 19psi, which is what you said you're hitting, will support 26lbs/min. The t25 is rated at 23lbs/min...

I'm not arguing either, I'm trying to show you why it can't be as easy as a fuel pump rewire to solve your problem.

 

[RayBan GST]

thank you gofer , amazing facts indeed at least now i am sure that i wont be running lean at 19 psi and i wont be damaging the engine. so no need to worry about the rewire.

i will start looking at some other things now to check what is happening

BIG THANKS

 

[Swarley815]

Like gofer said......without a wideband you will be guessing! $200 bucks is better than a rebuild!

 

[my dreamt dsm]

Old thread but to elaborate. I ran 17 psi all the way to redline(adustable fp actuator) and idc was only at 65 - 68%. I could of push the t25 to 21 psi and still be fine( not recommended). On a side note. 17psi daily and that t25 starts to shaft play very quick. I had no rewire pump, stock injectors.
One thing that could really benefit you will be a logger. EVERY CAR is different.

 

[91boostedgst]

In my opinion 750cc injectors would be great start with but i seen that u dont have a fuel management system id recommend getting somethin like link and get a walley 255 for a fuel pump