not happy with performance

[92awdbird]

so i got a bunch of mods and did some tuning but get a bunch of knock. not able to show a log yet but i can say

that im getting knock at 15 psi in second gear. full boost is 20 psi because ofcreep. been thinking of water/meth

injection. would this be the way to solve the problem? getting about 14 counts of knock. another

idea was to use a intake sock to keep the final intaketemp down. it sucks that i got this car that's capible

of good times but it sucks i cant use it to its full potential. i had this problem for a while and have asked a bunch

of questions on full throttle network but with no log its kinda pointless. just thought of this also....i haven't

changed the fuel filter for 60k. would that be a problem? i hope i posted this in the correct spot. thanks for the

help!

 

[Chill Kill Kult]

man I don't know. Everything I was thinking of has been modded/improved. maybe losing fuel pressure under boost, maybe intercooler isn't getting enough air, maybe bad gas (fuel). I'm going to keep thinking about this one.

 

[CrawlinZX14]

Try adding some fuel to your base pressure. if your at 37psi now, try 43psi base and see what happens. Depending on the ambient temp and humidity it can also have adverse effects as well, but I would not start out with meth on it at this point. Seems a lil premature on that front. To me it sounds like your losing fuel. Weather its your fuel pressure dropping off, or your injectors not being up to par. Hell u could have dirt in your injectors causing them to not run right. Check your duty cycle on your injectors, and your fuel pressure to start with. If your duty cycle is over 80% at WOT, then you need larger injectors.

 

[FatManDangerous]

What are your AFR's? Timing? Does it happen in any other gear?

 

[92awdbird]

well i got injector clinic 750cc injectors that were installed about 8 months ago and the quality of fuel is 92 octane. i dont fill up the tank past half just so i dont have water in the fuel. on the timing part of the question. it seems its kinda aggressive because of the stage 3 ecu tune for the injectors base fuel pressure and octane. heres a little info on the car...

Bolt-on Modifications:
2.5" inlet vertical flow fmic 23"x11"x3" core,tial 50mm bov,egr block off,cx racing big 16 G, evo3 mani, atmo dump, 3" megan racing full exhaust.

Engine Management:
dsm chips stage 3 ecu, DSMChips.com | DSM ECU Chips Enchanced by Keydiver set for 750 cc inj, base pressure of 37 psi, fpr, 190 pump, maft translator gen2 w/3.5 gm ls1 maf,innovate lc-1 wb,auto meter ultra-lite boost gauge,AEM tru boost ebc, mmcd palm logger,log works 2,

Engine Internals:
de burr porting from dsm graveyard,272 hks regrinds, manley springs, arp head studs, felpro head gasket w/2 coats copper spray.

Drivetrain Modifications:
act 6 puck solid,11.5 lbs act flywheel, solid motor mounts, ss clutch line, solid mount carrier bearing bushing.

Suspension Modifications:
megan racing coilover. 17" enkei, bf goodrich kdw 2.

so i hope this helps a little.

 

[clipto]

More fuel!Bigger fuel pump(255).How and who is tuning your car.Your setup should handle the 16g no problem I think just little more study on your tuning skills.Forget about 750cc 1000cc all the way, but not needed.I would ditch the maf-t and chip and just get ecmlink.

 

[92awdbird]

im doing all the tuning for the car. do you think that the 190 is not pushing enough fuel? i would like to use what i got for now because i dont have the money to start fresh.was talking a lot with turbo bob from the full throttle network forums. he was telling me to keep the trims in the 80% range as i did but there only seems to be running rich. im thinking that ambient temps amd intercooler size are the problem. the i/c is not big enough to handle the 20 psi boost. thats why i was thinking meth/water injection. what do you think?

 

[Alex7747]

Try adding some fuel to your base pressure. if your at 37psi now, try 43psi base and see what happens. Depending on the ambient temp and humidity it can also have adverse effects as well, but I would not start out with meth on it at this point. Seems a lil premature on that front. To me it sounds like your losing fuel. Weather its your fuel pressure dropping off, or your injectors not being up to par. Hell u could have dirt in your injectors causing them to not run right. Check your duty cycle on your injectors, and your fuel pressure to start with. If your duty cycle is over 80% at WOT, then you need larger injectors.

Do this first and report back. Also you should replace the fuel filter, and clean the fuel injectors. The 190 pump should support a 16g's air flow at 15-20 psi. Especially with 37 base fuel pressure. And a rewire for the fuel pump wouldn't hurt either.

 

[clipto]

im doing all the tuning for the car. do you think that the 190 is not pushing enough fuel? i would like to use what i got for now because i dont have the money to start fresh.was talking a lot with turbo bob from the full throttle network forums. he was telling me to keep the trims in the 80% range as i did but there only seems to be running rich. im thinking that ambient temps amd intercooler size are the problem. the i/c is not big enough to handle the 20 psi boost. thats why i was thinking meth/water injection. what do you think?

You should have enough to support the 16g especially at 15psi.I would really work on the tune try adding more fuel.On one of my cars I am running 19psi on a 16g with just a 255 fuel pump and 650cc injectors so you should be fine, just touch up on the tuning and well go from there.

 

[92awdbird]

if its slow at the shop friday ill pump up the pressure and see whats going on with the duty cycle. im also going to clean the maf and change the fuel filter and get back to you. i hate knock and its taking the fun out of driving!!!!! thanks guys!!!

 

[clipto]

if its slow at the shop friday ill pump up the pressure and see whats going on with the duty cycle. im also going to clean the maf and change the fuel filter and get back to you. i hate knock and its taking the fun out of driving!!!!! thanks guys!!!

What kind of octane fuel do you have and are running in hawaii?

 

[Chill Kill Kult]

^ already stated 92 octane.

It's a real long shot. but you could have oil built up in your intercooler, it would decrease the efficiency a fair amount. if your IC isn't that old or borrowed from another car (used parts) I wouldn't worry about it. I was just thinking randomly.

 

[MichaelSuch]

It's a real long shot. but you could have oil built up in your intercooler

If there's that much oil in the intercooler to cause efficiency problems then he has bigger issues to worry about. Have you checked the condition of your knock sensor yet? Every 1g I've owned (4 so far) they all were leaking goo and needed replaced.

 

[clipto]

^ already stated 92 octane.

It's a real long shot. but you could have oil built up in your intercooler, it would decrease the efficiency a fair amount. if your IC isn't that old or borrowed from another car (used parts) I wouldn't worry about it. I was just thinking randomly.

True statement to check the oil in the intercooler to help intake temps and efficency, also I didn't notice the 92 octane I missed that.But the intercooler size should be fine the ssautochrome is 28 x7 x 2.5 and not having any issues with that.I am still bias about your tuning equiptment especially the controll of tune with the 272 cams and all your supporting mods.My biggest thing still would be ditching all that crap no offence, but switching to something like ecmlink I am ganna stick with that no offence but running a chip only made to do so much and a maf-t no offence is old school plus you don't have anything like safc to do fuel trims.Don't get me wrong they all work fine but I think you will get the results if you switch to ecmlink.Not that it matters I think you will be fine with the 190 and maybe rewire if you want but I would of just got a 255 imo but sence your already got the 190 thats fine.

 

[Dsmkauai]

I'll be making a trip over to Oahu soon I may be able to help a bit. Let me know

 

[91stocker]

How's he going to adjust base fuel pressure with out an afpr?

 

[CrawlinZX14]

Ok, to give you an idea, I have an OEM fuel pump with a 50trim pushin 15psi. If you add fuel pressure your injectors do not have to work as hard. So a poor mans method is to add base pressure in order to lower your duty cycle on your injectors. I guess other than that, have you checked the flow on your intercooler? Make sure nothing is clogged? Do u have any readings of your intake temps at all?

 

[josh1095]

im shocked no one has attacked the cx turbo yet! tho, from my limited knowledge, air is air. it shoudl be working. unless ## lacking fuel. check the iat's and afrs. that could tell u if its a fake knock or its actually happening. atleast thatd rule out a bad sensor. i kno little about turbo cars but i do know that detonation even in small amounts does tremendous damage.
and whoever b4 me said it first: go with link and itll work

 

[1glaserfwd]

I agree dsmlink is a greater way of tuning, but the dsmchip is a good way as well. I went 11.99 on a 16g and full weight fwd 2g a couple years ago. You should not be knocking at 15psi with 750cc injectors and a 190lph pump. It could very easily be phantom knock!! Does the car knock with wastegate pressure? BTW I would change that fuel filter asap!!

 

[spadepro22]

As far as cleaning injectors, what are you guys using?

 

[josh1095]

i would use a can of carb cleaner and soak em. but im talkin out my ass, ive used that technique to clean motorcyle carbs etc.. i would take any rubber grommets off before doing so when cleaning injectors. another way would be to apply voltage to them and make them pass thru some injector cleaner. just a thought. also, when experiencing knock, it would be nice to see what pressure ## fuel is at. if it drops i would look directly at the fuel filter or pump. theres a screen at the bootom of the pum on 420a's should be the same on gst. could be clogged. air leak past the maf would also cause lean conditions. i speak only of experience from n/a vehicles but have seent hat happen a few times. IM gasket, TB gasket, any hoses sucking in unmetered air... all lead to lean conditions. dont run it hard dude. det's are brutal on pistons and rings. the fuel explodes violently causing pitting, or even damage to ex vavles due to the increased heat.

 

[ChrisMgst]

im with CLIPTO. 255 pump

 

[Fiascoxl]

Start by changing the fuel filter and get rid of the oem feed line that goes from the filter to the rail. That banjo bolt is very restrictive.

 

[RWD4G63]

This thread is useless without afr's and timing numbers. Do you have a wideband installed?

Otherwise you are shooting in the dark. There are all kinds of knock, and it's impossible to tell what kind until we see the tune.

 

[92awdbird]

i do have a wide band, innovate ls-1. i havent got it to work correctly on the lap top yet. changed the fuel filter and noticed a little less knock. im thinking its the intake air temp. i guess some race gas would be one way to figure out if its air temp issue. i did up the fpr to 40 psi.