2G 450cc Stock injectors with 15-17 PSI boost?

[xXEclipse]

Just got my car back from the mechanic he said he downtuned my injectors so i can drive now(they were dumping too much fuel) im boosting around 15-17 PSI

Its still dumping too much fuel... If i put stock injectors will i be ok boosting that much?

Again he said he CANT lower the boost anymore -_-

 

[knochgoon24]

What size injectors are you trying to run and what are you using to tune?

 

[xXEclipse]

550's with an AFC

I wanna run my stock ones cause these are just dumping too much fuel

 

[throwedgsx]

17 psi on 450s would be too close if not over 80% injector duty cycle. You always want to stay below 80%. You should keep running the 550s and do some more tuning with the afc.

 

[khartley]

What is your turbo/wastegate/boost controller setup? I don't understand why he 'can't'.

 

[knochgoon24]

You should be able to dial in 550's with an AFC.

First, are you sure your mechanic knows what he's doing as far as tuning (most don't)?
And two, how do you know they're just dumping fuel? What are you're current adjustments? Are you sure it's setup correctly?

 

[xXEclipse]

Feels like they're dumping ... The engine floods and car won't really go anymore... I dont have a boost controller and my wastegate is opened all the way

 

[CHAR-FT]

Sounds like the guy does NOT know what he is doing, return it to stock ASAP and then take it somewhere where they can tune it the right way. sorry about your luck. Sounds like you yourself need to do some reading, that way situations like this cant happen.

What is this guy tuning with? I would get an S-AFCII so you can learn to do it yourself. This guys going to ruin your 6bolt set-up if you don't do something about it now.

 

[9!'clipseDOHC]

http://www.dsmtuners.com/forums/newbie-forum/382971-my-pipe-connecting-my-turbo-my-intercooler-popped-off-opinions-help-please.html

Based on this thread and his other thread ^, this guy doesn't know a thing about his car and neither does his mechanic.

A. Do you have a boost gauge? If so, What does it say? (on the other thread he said his mechanic told him he was boosting 15-17)

B. Have you ever used the AFC or does your "mechanic" do it for you?

C. 550's with an AFC running 17 psi is not "dumping to much fuel". That is what is AFC is for. Is it even hooked up? Have you adjusted it at all?

D. Do you have an aftermarket fuel pump? If so, what size and do you have an Adjustable Fuel Pressure Regulator.

E. Do you have a 3" downpipe? If you are really boosting 15-17 on the stock T-25 then either there is something wrong or you are creeping a lot. Just looking for possible solutions.

F. Make sure that your profile is up to date on your mods so that we can better help you.

 

[xXEclipse]

I bought the car like this WITH the AFC and i dont know personally how to tune it, yes i have a 3 in downpipe.

And the AFC isnt tuned in properlly obviousally thats why im dumping too much fuel.

 

[dsmtalon2008]

I bought the car like this WITH the AFC and i dont know personally how to tune it, yes i have a 3 in downpipe.

And the AFC isnt tuned in properlly obviousally thats why im dumping too much fuel.

Gotta love the people that INSIST they are correct when they are OBVIOUSLY wrong.

 

[Tanro]

My best advice to you is to return the car to stock. Stock boost, stock injectors. Unhook the AFC, clean it up really nice and park it. Put for sale, and get something with an LS1 in it. I think it might be more up your alley as far as modding goes.

 

[hubz91talontsi]

Well i know you cant run 21psi, my idc's were around 121% in 2nd gear.

 

[xXEclipse]

So your saying im not dumping too much fuel? Then whats the problem.

 

[dt23400]

well if your going to attempt to do the tuning side or have ## mechanic do the tuning side you should probably get a wideband. After that you can watch your afrs and u can dial it in with the afc. or return it back to stock injectors and zero out the afc that way your running stock and go back to stock boost.

 

[xXEclipse]

I want to do this but the guy says he cant lower my boost anymore, i just spoke to the previous owner he says its got a o2 housing from the big 16G would that do it??

 

[gofer]

You could be "dumping" (we call it running rich) too much fuel for multiple reasons, it could be from modifications done to your car or it could be from poor maintenance and a failing OEM part.

Since the car came in this condition you've got no idea what kind of botched wiring (if any) was done when the previous owner installed that AFC.

As far as maintenance goes you could be running rich because of a failing front o2 sensor, coolant temp. sensor, or an old fuel pressure regulator. Is your CEL illuminated and if so have you pulled any codes off of it, these are of course helpful when troubleshooting this type of stuff. ENSURE your front o2 sensor isn't plugged into your cruise control solenoid, believe it or not these two connectors will plug right into each other. If your not getting a CEL your best bet is to remove your AFC (not just unplugging either, you've got to reconnect wires at the ECU harness) and revert back to your stock 450cc injectors for the time being.

Test your wastegate actuator attached to your turbo, the stock t25 actuator should open between 9-12psi. If it does in fact open like it should your more than likely getting boost creep from your bigger exhaust upgrades. If it makes you feel any better about running 15-17psi your t25's MAX airflow is 25 lbs/min. You can't be 100% sure without having a wideband o2 sensor installed but your stock 450cc injectors should support whatever amount of boost you throw at them with the t25 installed. That amount of boost really pisses off that small turbo so don't expect the turbo to last long...

Here's a video so you can test your wastegate actuator.

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