sr tuning tips and ecu mystery

[bruceguy]

well, i had an sr for about 4 months now in my hatchback now, and now my goal is to get to 300whp. every thread i read about building an sr with 400+ hp is not what im looking for, i want a nice power and keep decent mpg.(also dont have shop and i have a tight budget-want to spend it right) so there is a couple of questions i have for this "moderate tuning" that i want to execute.

1. is it possible to keep the stock 370cc injectors?is it safe for what im doing?

2.do i need a fpr if im running a walbro 255 pump?

3.are there any good manuel boostcontroler? 10-12psi is what i wanted.(also read about aftermarket actuator for the t25- more detials if u have)

4. any recommended wide bands, what not get, etc...

5. any other parts recomended?

6. WHAT THE HELL IS IN MY ECU???! I showed someone who been through 3 sr motors, and he was dumbfounded. here are some pics.

http://i391.photobucket.com/albums/oo358/gallardoman/IMG_2281.jpg

http://i391.photobucket.com/albums/oo358/gallardoman/IMG_2280.jpg

this ecu has some sort of tune in it, but its unknown. can i pug into it somehow or is it better to sell it and get stock ecu + SAFC? so if anyone can identify this, it would help out so much!

thank you guys in advance for the help.

[DoriftoPnoy]

1. go bigger. its for peace of mind
2. no but if you get bigger injectors yes
3. electronic boost controller is the way to go. but im running a turboxs dual stage one right now and its alright. before that i had a homemade one.
4. wideband u would get if u were turning the car yourself. prolly good to have since you'd be turning up the boost and running bigger injectors.
5. hopefully you're not on a stock restrictive exhaust
6. i think (not sure) you have some sorta rom tune. dunno what kind but my bro's ecu has a daughterboard kinda like that. you can't really plug into it. just have to find out exactly what kind and then go to that company and request a tune for whatever you have ex. turbo, injectors, and other mods

[bruceguy]

^^ thanks, that really helps.

what companies make that kind of rom devices? is worth much?

will having a fpr on stock 370cc injectors be a good idea?

[bl3ujay07]

370cc is not close to being enough for anything close to 300 hp. even 550cc imo is pushing it. You want 740 or maybe even 850cc (what i am using and is plenty). You are going to need a big turbo and a good build to get 300 hp with only 10-12 psi.

[Def]

That's a daughterboard. Ask a local guy with a chip burner to dump the contents and you'll at least have a rough idea of what's on there. If it came from Japan 99.9999% chance the tune completely sucks.

[S14DB]

well, i had an sr for about 4 months now in my hatchback now, and now my goal is to get to 300whp. every thread i read about building an sr with 400+ hp is not what im looking for, i want a nice power and keep decent mpg.(also dont have shop and i have a tight budget-want to spend it right) so there is a couple of questions i have for this "moderate tuning" that i want to execute.

1. is it possible to keep the stock 370cc injectors?is it safe for what im doing?

2.do i need a fpr if im running a walbro 255 pump?

3.are there any good manuel boostcontroler? 10-12psi is what i wanted.(also read about aftermarket actuator for the t25- more detials if u have)

4. any recommended wide bands, what not get, etc...

5. any other parts recomended?

6. WHAT THE HELL IS IN MY ECU???! I showed someone who been through 3 sr motors, and he was dumbfounded. here are some pics.

http://i391.photobucket.com/albums/oo358/gallardoman/IMG_2281.jpg

http://i391.photobucket.com/albums/oo358/gallardoman/IMG_2280.jpg

this ecu has some sort of tune in it, but its unknown. can i pug into it somehow or is it better to sell it and get stock ecu + SAFC? so if anyone can identify this, it would help out so much!

thank you guys in advance for the help.


1. is it possible to keep the stock 370cc injectors?is it safe for what im doing?
No. RC Fuel Injection (http://www.rceng.com/technical.aspx)
2.do i need a fpr if im running a walbro 255 pump?
Yes the Walbro runs at higher pressure then the stock pump and will overwhelm the stock fpr and it will fail.
3.are there any good manuel boostcontroler? 10-12psi is what i wanted.(also read about aftermarket actuator for the t25- more detials if u have)
MBC's are a bandaid. upgraded actuator is a better solution.
4. any recommended wide bands, what not get, etc...
Most use the same Bosch(VW) sensor. It depends on the features(display logging) you need.
6. WHAT THE HELL IS IN MY ECU???! I showed someone who been through 3 sr motors, and he was dumbfounded. here are some pics.
Daughter card holding a ROM tune. Looks old and the ROM chips soldered to the daughter card.



I would get a new tune. But, a SAFC is for timing a tune not to replace one. Even then it only affects only fuel in a limited range. Our ECU's timing are load dependent. SAFC clamps the MAF/MAP to change the load the ECU sees. Gets the fuel trimmed but usually throws the timing in the opposite direction you want.

I would see if you can get the board you have re-tuned to your setup. If it turns out to be a generic/compatible board and roms you should be able to get a rom tune for cheaper cause you already have the board in and they just have to swap chips.

[Def]

2.do i need a fpr if im running a walbro 255 pump?
Yes the Walbro runs at higher pressure then the stock pump and will overwhelm the stock fpr and it will fail.

You might run slightly higher fuel pressure with a Walbro 255 and stock FPR, but it will not cause it to fail. I've been running this combo for 5 years with no problems.


6. WHAT THE HELL IS IN MY ECU???! I showed someone who been through 3 sr motors, and he was dumbfounded. here are some pics.
Daughter card holding a ROM tune. Looks old and the ROM chips soldered to the daughter card.




Those aren't soldered in, they're in sockets. I'm willing to bet it's an old daughterboard with UV erase EPROMS(hence the stickers) with an odd/even arrangement.

[steve shadows]

First of all the stock fuel pressure regulator will not fail if you bump up the pressure with a larger pump.

In fact you can jam 70-80 psi through one for extended periods if its in good shape. It's actually more robust in stock form than many of the aftermarket injectors.

Don't get rebuilt etc. Buy NICE NEW DENSO or NISMO side feed injectors for your setup. Dont skimp or rebuild your injectors. The valving and lag times should come new, with new bodies and all. Not just bored out pintle caps or holes in the tips of the injectors to simulate higher flow. In my experience the cars never run as well as cars with nice new fresh high impedence denso injectors from the factory.

S-AFC are garbage. If you don't already have one don't waste your money. It will throw off your timing and cause your car to actually produce less HP even if the AFR is closer to where you want. In my experience they usually won't let you tune the car to anywhere near what you want as the AFR either. Big waste imo. Does more harm than good on a hot wire based maf system (which is what most nissans are).

[S14DB]

You might run slightly higher fuel pressure with a Walbro 255 and stock FPR, but it will not cause it to fail. I've been running this combo for 5 years with no problems.
My FPR died and I started running lean when I installed the walbro. I also had a friend have the same thing happen. Just cause it hasn't happened to you doesn't mean it doesn't occur.


Those aren't soldered in, they're in sockets. I'm willing to bet it's an old daughterboard with UV erase EPROMS(hence the stickers) with an odd/even arrangement.
I'm sure they are in sockets, joking. Just so small and bad picture.

They are UV ROMS you can see the window outline in the stickers.

[bruceguy]

thanks for all the helpfull info, now i have an idea what to do.

and yes, the board that holds the two chips are in sockets, when i first installed my sr it ran like crap for the first week, and finally when i opened up the ecu, that board was not properly pushed in, after that it ran fairly good.

i still get back fire like crazy when im on it thou, and its not like the break up crakling backfire, its like nothing is happening and BOOOOOMMM! similar to a gunshot!
thats why someone told me to get a fpr asap.

and yes i do plan to complete my turbo back open exhaust, i just picked up a stainless turbo dump/down pipe.

so im going to keep my ecu, and find/retune a/my chip that corresponds with my setup?

im still a little confused, should i install a fpr anyways on stock injectors since im going to install bigger injectors?

[S14DB]

FPR is a supporting mod not a power making mod. It won't hurt to install it at any time.

Backfire is ether running rich or a timing issue. Your tune is probably not matched to your setup. Since you don't know what the tune is it is probably best to get a retune.