Fuel System

[Prodigyman]

I currently got 97 GSX with following performance mods (+ a lot of other non performance mods)

FPBIGT28
2.5" custom intercooler piping (welded xept the intake manifold and FMIC IN/Out)
31" FMIC (AN overkill I think)
Greddy Type RS BOV
Injen Intake
K&N Filter
ACT 2100 Clutch
Fidanza Flywheel
Hybrid Connection 2.5" O2 sensor housing
Customer 2.5" DP
Custom 3" Cat back (3" Magna Flow high flow cat and "muffler")

It shows now that I run about 12-14 PSI at WOT

My problem is that it's slow for me now! Loosing (at the end by 2 car length, @ 210 km/hour) to stage 2 SRT4 just killed me last night and got me thinking. I have Greedy Profec B II Boost controller brand new in box.

I really don't have the money ATM to do complete update to the fuel system so what do you think I can push out of the stock fuel system ATM ? I was thinking doing complete rewire of my Fuel Pump and maybe get Walbro 190lph Fuel Pump along with it and do MAF Mods and run it about 16 PSI or so.

Because ATM after 4-5 K 3-rd+ gear it just slow and overall performance is maybe about 250-270 WHP MAX if not that (haven't dyno'ed it yet). I baby the car most of the time, change oil every 4000 KM, never boot it around, most parts in the engine bay are new from Water/Power steering pump to wiring (since most of the stuff broke and had to be replaced). Engine has 30 000 mi on it (it was completely rebuild). My Real life goal was really ~ 300 WHP but obviously I don't have anything close to that ATM.

Any suggestions would be appreciated.

 

[nitrouskris]

buy 255 or a surpa pump, dont waste your money on a 190 pump

 

[Eastwood95]

A 190lph pump will support a 16psi and more on a T28 with 550cc injectors........but then you also need "SOME" way of tuning it.

If you just bought the fuel pump, you could turn up boost...........but you need some monitoring devices, aka EGT, Wideband o2, Datalogger.

 

[DGajre777]

buy 255 or a surpa pump, dont waste your money on a 190 pump

There is absolutely no reason to get a 255 pump for a Big T28. A 190 pump will work fine for EvoIIIs. I know a member running 22psi on a 50 trim with a 190 pump, so please tell me why a 190 pump is a waste of money?


Prodigyman- Unless you plan on getting a bigger turbo after the T28, stick with the 190. Another reason to go with the 190 is that you can get away without using an AFPR. With the 255 you need an AFPR to prevent fuel overrun at idle and when you decelerate.

If you upgrade your injectors to 550ccs, you'll need something control it. A MAFT is enough to tune with 550ccs alone (and a GM MAF). If you want more precise fuel control that a MAFT, look at the MAFT Gen II, it has more settings than an SAFC II.

Get a 190, get a logger, turn the boost up and tune it until you get bigger injectors and some kind of fuel controller.

If you don't want to get a seperate logger and MAFT, SAFC look at ECUPlus - www.ecuplus.com/features.htm. If you have extra funds for an Eprom ECU, DSMLink it.

 

[TSIMonsteR]

I don't thing an MAFT set up would be ideal for you. Stick you the SAFC/Logger combo, or go with DSMLink. If I was in your situation, I'd get the 255 and an AFPR Kit for now, and save up for DSMLink and some injectors

 

[prostreetdsmx1]

bro you are one of those points in your build that you need to really figure out what route you plan on going. If you plan on sticking with the same base setup then you just need to get some 550's, a 190 FP, S-AFC or MAFTII to take advantage of you setup. I am personally not a huge fan of the 28 because it tends to run out of breath up top and i can tell you that an intercooler that size that i am assuming is also Bar & Plate isn't helping you any either as far as spool and performance.

One good options is to look around for some used parts from people that are trusted on the boards. You should also check with some shops for deals on used injectors, used S-AFC's etc... you can save some money and as long as you buy from known people/shops you should be able to have full faith in you purchase.

sell that Greddy EBC and buy your sell a $50 Joe P. and use the rest of the money from the sale toward the other parts you need.

Best of luck to you in your project.

 

[Prodigyman]

Thx for the info guys. Yeah my goal is to have about 300-320 WHP and that's why I went with current turbo and setup. Especially that my car is AWD and 2800 RPM full boost spool up with FPBigT28 is also nice. From what I researched and read here I might go with GM MAF, MAFT II 190 FP and 550C and turn up boost to 16-18 PSI level and sell my Greedy EBC and get some manual one. With this addition and proper turning I hope I can reach my 320 WHP goal. Also what's a good brand for 550CC injector's ### I saw may from $100 to $400.

 

[Prodigyman]

I also was thinking of selling my new FPBT28 and maybe getting something bigger like EVO III. Because top end is just noise ATM and no power I can really feel it. It also could be my stock wired pump. So I am not sure what to do. You guys thinking with current setup + bigger turbo and my fuel mods I listed above I can safely run it as daily driver @ ~ 300-320 WHP? Or just leave the FPBT28?

 

[DGajre777]

I also was thinking of selling my new FPBT28 and maybe getting something bigger like EVO III. Because top end is just noise ATM and no power I can really feel it. It also could be my stock wired pump. So I am not sure what to do. You guys thinking with current setup + bigger turbo and my fuel mods I listed above I can safely run it as daily driver @ ~ 300-320 WHP? Or just leave the FPBT28?

The Big T28 won't really come alive at the 12-14psi. When you push it to about 22+psi with fuel mods, then you'll feel the kick. You can't push it to that psi without fuel mods.

I will have to agree with prostreetdsmx1, you are at a point where you need to decide what you want. If you want a bigger turbo, plan big with 255 pump, AFPR, 660cc injectors (FIC or PTE), etc. With bigger injectors you need to find a way to control it - SAFC, MAFT Gen II, ECUPlus, DSMLink etc.

You can safely run a DSM and make 400WHP reliably, if you know how to tune. What are you planning on doing with the 320WHP goal? Is it for the street or for a track? The words "Wet Nitrous kit on a T28" come to mind.

 

[eclipsh]

A super cheap thing to do right now would be rewiring your pump. You need to do it sooner or later and it will help immediately. Below is a tech article on how I did it.

http://www.dsmtuners.com/forums/showthread.php?t=211560

Also a little experience info here: go with new injectors. I tried buying used RX7 680 injectors to save some cash and it ended up being a real pain. Thanks to one leaking cap I'm still trying to find one more injector to finish off the set. Fuel Injector Clinic had great customer service when I talked to the owner.

 

[Prodigyman]

Yeah I am defiantly going to rewire and even get 190 FP. My goal for 320 WHP is for a daily driver which still has balls and do occasional legal racing. I really don't want anything more and I am pretty set on that figure. As I stated before with 190 FP + rewire, new 550cc, GM MAF, MAFT Gen II with proper tuning will I be able to produce that WHP goal and with what max PSI can I push it to reach it + is there anything else I should get to properly tune it?

 

[eclipsh]

I'm not entirely sure why you're going for the GM MAF. Your stock MAS is more than adequate for 320whp. Why not just go for the SAFCII, DSMLink or an EPROM chip if you have an EPROM ECU and save some money? Not to mention hassle. Everything I've read about the MAF translator says it is a major headache to tune.

 

[ChicksDigBoost]

The MAFT Gen II is a little different, but in order to take advantage of its new features and tuning, you need a wideband. I would look towards the eprom ecu route and then you can always get dsmlink if you want it.

 

[Prodigyman]

I'm not entirely sure why you're going for the GM MAF. Your stock MAS is more than adequate for 320whp. Why not just go for the SAFCII, DSMLink or an EPROM chip if you have an EPROM ECU and save some money? Not to mention hassle. Everything I've read about the MAF translator says it is a major headache to tune.

Well I have Greedy RS BOV and its venting, thought correctly adjusted so it never stalls or anything like that but I want to go on a safe and reliable side too.

As for DSM Link and everything else fuel related, to tell you the truth, I am kind of confused. What I thought is if I get GM MAF and MAFT I can maybe adjust A/F ratio to compensate for 550cc injectors and able to safely turn up the boost (16-18 PSI on FPBT28) to reach my HP goal with current supporting mods with least money spent since I already invested + Repaired a lot but if not that case I need some help

 

[Eastwood95]

ok, heres some of the must do's to run 18-20psi on a T28 and 21-23psi on racegas
sell the electronic boost controller and get a manual one...
buy a 190 fuel pump...
rewire the fuel pump...
buy new 550cc injectors...
buy a new or used SAFC I or II...

a lot of people run that setup or something similar(16g) safely........but you need something to tune and monitor so............

you can also:
buy a datalogger...........and if there's any money left, get the dsmlink, an EGT guage and/or wideband o2 to monitor tuning as well.

you dont need a different maf. Your stock 2G MAS will support up to 400hp,
you can adjust idle and A/F with the SAFC

 

[DGajre777]

Just because your vented BOV sounds okay, doesn't mean you are not having other issues. Reroute that BOV until you get a MAFT setup.

For a Big T28, max psi should be about 22 psi on pump gas, 25 psi on race gas. Or you can keep turning the boost up until you see knock. This is why you need a logger or DSMLink (which has a logger and a fuel computer). The MAFT, Gen I or Gen II is not going to show you knock. On a 2G you can't see knock directly but you can tell when you get a sudden change in timing.

And I wouldn't waste my money on an EGT gauge if you are getting a wideband o2.

 

[2gGSX]

In case you are really sticking with the Big T28 and when you do in fact get up to the 20+ psi boost range, you may want to look into FP's 17 psi actuator which will allow you to hold more boost longer. This is a key weakness of the Big T28 compared to a 16g variant (note that's not to say 16g's don't lose boost in the upper RPM ranges either, but in my experience not as drastic). People on the DSMLink forums have quoted an average of around 3 lbs/min airflow increase from just the actuator upgrade.

Edit: no more paragraph-lengthed sentences.

 

[Ultimatedsm]

bro you are one of those points in your build that you need to really figure out what route you plan on going. If you plan on sticking with the same base setup then you just need to get some 550's, a 190 FP, S-AFC or MAFTII to take advantage of you setup. I am personally not a huge fan of the 28 because it tends to run out of breath up top and i can tell you that an intercooler that size that i am assuming is also Bar & Plate isn't helping you any either as far as spool and performance.

One good options is to look around for some used parts from people that are trusted on the boards. You should also check with some shops for deals on used injectors, used S-AFC's etc... you can save some money and as long as you buy from known people/shops you should be able to have full faith in you purchase.

sell that Greddy EBC and buy your sell a $50 Joe P. and use the rest of the money from the sale toward the other parts you need.

Best of luck to you in your project.

I am just curious on your comment about his intercooler, you think he is loosing performance over his stocker with this size of an intercooler? I thought Bar and Plate is better then Tube and Fin? Let me know. Thank you.

 

[Prodigyman]

ok, heres some of the must do's to run 18-20psi on a T28 and 21-23psi on racegas
sell the electronic boost controller and get a manual one...
buy a 190 fuel pump...
rewire the fuel pump...
buy new 550cc injectors...
buy a new or used SAFC I or II...

a lot of people run that setup or something similar(16g) safely........but you need something to tune and monitor so............

you can also:
buy a datalogger...........and if there's any money left, get the dsmlink, an EGT guage and/or wideband o2 to monitor tuning as well.

you dont need a different maf. Your stock 2G MAS will support up to 400hp,
you can adjust idle and A/F with the SAFC

Thx for the info guys. But what about

Stage 3 EPROM-type 1995 ECU (For 550cc)
http://www.dsmchips.com/2g.html
550cc
Rewire new 190 FP
+18/20 PSI?

 

[eclipsh]

For what it's worth there is a classified add for a set of 780cc injectors for $180 on the site. They might be overkill for your goals but it would give you flexability if (when) you change your mind and want more power.

 

[DGajre777]

Thx for the info guys. But what about

Stage 3 EPROM-type 1995 ECU (For 550cc)
http://www.dsmchips.com/2g.html
550cc
Rewire new 190 FP
+18/20 PSI?

I don't think you did enough research on the DSMChips...

"Remember, to use these chips you MUST have an EPROM-type 1995 Turbo ECU.
Complete EPROM-type 1995 ECU's are also available, socketed and ready to go, for an additional $260, sold ONLY with my EPROM's!"

"Do I have to use an AFC with my chip?
Generally, yes. Although the changes I make to the Global Fuel and MAS Compensation get VERY close, and make it easier to tune, it is still recommended that you have some tunability, such as an Air-Fuel computer or a GOOD adjustable Fuel Pressure Regulator. In addition, every car is different, so you may require more/less fuel depending on your situation"

Why spend $260 on an e-prom ecu, $125 to chip it stage 3 and then get a SAFC? WTF If you have that much money, just get DSMLink. For 550ccs MAFT or SAFC will do. Don't complicate and over think things. If you decide to get 650ccs get SAFC or MAFT+SAFC or MAFT Gen II.

 

[Prodigyman]

I don't think you did enough research on the DSMChips...

"Remember, to use these chips you MUST have an EPROM-type 1995 Turbo ECU.
Complete EPROM-type 1995 ECU's are also available, socketed and ready to go, for an additional $260, sold ONLY with my EPROM's!"

"Do I have to use an AFC with my chip?
Generally, yes. Although the changes I make to the Global Fuel and MAS Compensation get VERY close, and make it easier to tune, it is still recommended that you have some tunability, such as an Air-Fuel computer or a GOOD adjustable Fuel Pressure Regulator. In addition, every car is different, so you may require more/less fuel depending on your situation"

Why spend $260 on an e-prom ecu, $125 to chip it stage 3 and then get a SAFC? WTF If you have that much money, just get DSMLink. For 550ccs MAFT or SAFC will do. Don't complicate and over think things. If you decide to get 650ccs get SAFC or MAFT+SAFC or MAFT Gen II.

"Don't complicate and over think things" Yeah sometimes I tend to do that I'll take your advice on it. I'll get 190 FP, MAFT, GM MAF, 550cc SAFC and logger and see where it will take me @18-20 PSI. I'll post some dyno results here when I am done tuning and installing the parts.

Thx for the help guys

 

[alex99gst]

For what it's worth, I'm running 18 psi on my small 16g with a completely stock fuel system other than the GM MAF and MAFT. I only get knock at 6.5k+ rpm's. I just ordered an AFPR and 255 pump, so you could do fine without the SAFC, it's all just personal preference on how fine tuned you want it. I need to switch over to RPM mode on the MAFT and fine tune it sometime.

 

[DGajre777]

"Don't complicate and over think things" Yeah sometimes I tend to do that I'll take your advice on it. I'll get 190 FP, MAFT, GM MAF, 550cc SAFC and logger and see where it will take me @18-20 PSI. I'll post some dyno results here when I am done tuning and installing the parts.

Thx for the help guys

You can tune the 550cc injectors with a MAFT alone BUT instead of getting a SAFC for $269 and MAFT for $199, just get the MAFT Gen II for $269. The MAFT Gen II is like a SAFC and MAFT in one unit. If you have extra funds get the Innovate LC1 wideband. The MAFT Gen II and LC1 will be a much better setup.

Here's some more info on the MAFT Gen II -
http://www.dsmtuners.com/forums/showthread.php?t=225618 and
http://www.dsmtuners.com/forums/showthread.php?t=225628