Ok, I really didnt dick with the FPR we pulled off my friends 400hp rx-7, but its running at 80PSI at idle. Its takes about 3 to 4 seconds to get it to start up. Right before boost kicks in, it kind of hesitates and backfires. Is running that rich bad for me? Also, would I get more power by lowering the pressure?

Originally posted by biggnasty
Is running that rich bad for me? Also, would I get more power by lowering the pressure?

Yes, and yes.

oh goodness.

i bet it runs like shit and your out there driving it??

you need half of that with stock injectors.

holy shit a lil more and youll max out your pump at idle .lol .lower it between 47 - 55 psi at idle

Wow. I'm suprised it even idles like that. So when it raises the pressure in full boost it must be in the high 100's. crazy scary.

This is going to sound crazy, but... I took off my hood, and had my friend sit on the window holding onto the engine bay looking at the gauge on the regulator while i was at full boost. It was at 80, and at full boost went up to 87 to 88.

What the hell is going on here?

It seems to run good, just a little backfiring between shifts, and right before boost. Did I tell you that I have to hold the starter down for like 5 seconds to get it to start?

I just dont want to lean it out because the manual says for 8psi, you need around 85 to 90 psi under full boost.

Originally posted by biggnasty
This is going to sound crazy, but... I took off my hood, and had my friend sit on the window holding onto the engine bay looking at the gauge on the regulator while i was at full boost. It was at 80, and at full boost went up to 87 to 88. What the hell is going on here? It seems to run good, just a little backfiring between shifts, and right before boost. Did I tell you that I have to hold the starter down for like 5 seconds to get it to start? I just dont want to lean it out because the manual says for 8psi, you need around 85 to 90 psi under full boost.

Probably because it is a 1 to 1 regulator! You started at 80, ran 8 pounds of boost, and ended up at 87/88.

Originally posted by biggnasty
This is going to sound crazy, but... I took off my hood, and had my friend sit on the window holding onto the engine bay looking at the gauge on the regulator while i was at full boost. It was at 80, and at full boost went up to 87 to 88. What the hell is going on here? It seems to run good, just a little backfiring between shifts, and right before boost. Did I tell you that I have to hold the starter down for like 5 seconds to get it to start? I just dont want to lean it out because the manual says for 8psi, you need around 85 to 90 psi under full boost.

you have to lean it out . im surprised you didnt foul out the plugs already . that must be some scary shit sitting on the windshield at full boost lol

Yeah you may want to check to see if that regulator is a 1:1 or a rising rate regulator..its prob a 1:1,which is not going to work for your setup. You need something like a SFMU that is adjustable with the fuel pressure curve under boost, and need something much more higher under boost, more like a 12:1 ratio. Oh, and it may be of best interest to invest in a electric fuel pressure gauge for in the car, that way you wont have to keep hiring stuntmen to monitor your fuel pressure under boost lol.

Yeah, I talked to my boy, and he says he runs a constant 100 or so psi in his rx-7 (thats where I pulled the FPR), and it is a 1:1. But... Its working for me for now. It seems that the car has gotten used to it. I make crazy power, and can beat an STI. I'm deploying again REAL SOON, and I guess I'll just have to buy all my parts while in the desert again. So what brand of FPR/FMU would you guys suggest? But just remember my car runs fine at idle and 80 PSI. maybe its because I have the 270cc injectors in there?

Originally posted by biggnasty
Yeah, I talked to my boy, and he says he runs a constant 100 or so psi in his rx-7 (thats where I pulled the FPR), and it is a 1:1. But... Its working for me for now. It seems that the car has gotten used to it. I make crazy power, and can beat an STI. I'm deploying again REAL SOON, and I guess I'll just have to buy all my parts while in the desert again. So what brand of FPR/FMU would you guys suggest? But just remember my car runs fine at idle and 80 PSI. maybe its because I have the 270cc injectors in there?

the only time you run a 1:1 is when you have something like megasquirt . you need a vortech sfmu or megasquirt . at 7psi you should be over 80psi . thats actually real lean under boost if im correct . your motors not gonna last to long running lean .

Desert = money....buy the whole megasquirt setup, bigger turbo, supporting mods, etc etc :thumbsup

No, buy my SFMU and injectors! plug and play, you're done.
http://forums.2gnt.com/dcboard.php?az=show_topic&forum=16&topic_id=95672&mode=full

Originally posted by boosted60trimrst

Originally posted by biggnasty Yeah, I talked to my boy, and he says he runs a constant 100 or so psi in his rx-7 (thats where I pulled the FPR), and it is a 1:1. But... Its working for me for now. It seems that the car has gotten used to it. I make crazy power, and can beat an STI. I'm deploying again REAL SOON, and I guess I'll just have to buy all my parts while in the desert again. So what brand of FPR/FMU would you guys suggest? But just remember my car runs fine at idle and 80 PSI. maybe its because I have the 270cc injectors in there?

the only time you run a 1:1 is when you have something like megasquirt . you need a vortech sfmu or megasquirt . at 7psi you should be over 80psi . thats actually real lean under boost if im correct . your motors not gonna last to long running lean .

First off, you can not compare what a twin turbo RX-7 runs (when it comes turbo from the factory) and what your car does. Let me try and explain why as best I can. This is just how I understand this, so if I am wrong in any way, someone feel free to correct me.

Now, your car comes from the factory non-turbo. Your car is supposed to only see vacuum, never any positive (boost) pressure. So, your ECU basically has very simple maps (comparitively) as far as airflow and fuel are concerned.

The following is the reason why you need a fuel pressure regulator at all: Your injectors spray into your intake manifold, which normally just sees vacuum. Now, since you are a turbo car, you will now have boost pressure throughout your intake system, including your intake manifold. This means that now, there will be positive pressure when your injectors are trying to spray, and so, they will not be able to flow the same amount as they normally would. In a car that comes turbo from the factory (like a turbo DSM or RX-7), a 1:1 regulator is all that is needed. This is because as you increase boost 1 psi, you will need an increase in fuel pressure of 1 psi to match that.

However, the cars that come with turbos from the factory have ECU's 'ready' for boost pressure. They come with more complicated air and fuel maps. As airflow increases (which will happen as boost pressure increases), the ECU will automatically change to a the fuel map that matches that airflow. Now, with this increase in airflow, as you should know, you will need an increase in fuel. Normally, at idle or cruise, you will be running a very conservative air/fuel ratio. So, when you run boost pressure, the ECU will automatically richen the fuel system.

In your case however, your ECU has no idea what boost is. It does not 'know' that it needs to increase fuel with the increase in pressure. So, this is where your regulator comes into play. Instead of the 1:1 that is used in a factory turbo car, you need a 12:1 regulator, meaning fuel pressure will increase 12 psi for each 1 psi increase in pressure. So, even though your car will still try and supply the same amount of fuel as when you weren't turbo, the increase in fuel pressure will supply the increase in fuel that you need. Hopefully this all makes sense, and if it doesn't, I'm sure myself or someone else can clarify anything.

So, now you should realize that even though you may think you are running the 'required' 80 psi or so under boost, your car is not running the correct amount of fuel at all. Under idle conditions, your car should supply the same amount of fuel as before (what is it, around 50 psi or so?), but as boost pressure increases, your fuel should increase with each increase in pressure. So please, do you car a favor and keep researching. I hope this helps!

For your car to run right you need 47 psi at idle and 90-100 at 8 psi of boost. You will only achieve this with a rising rate FP regulator like an fmu or sfmu.

Your car is running fucked up right now weather you think it is or not. :rolleyes

I completly understand now. But as for the current situation, I'm going to keep things the way it is. I'll send the FMU to my buddy to install while I'm in the desert. I only have a few days left with my car. He has more turbo knowledge then me, so I think he will be able to tune it right.

Thanks for all the help guys. And just so you know, I do all my reading when I'm in the desert.

Originally posted by biggnasty
I completly understand now. But as for the current situation, I'm going to keep things the way it is. I'll send the FMU to my buddy to install while I'm in the desert. I only have a few days left with my car. He has more turbo knowledge then me, so I think he will be able to tune it right. Thanks for all the help guys. And just so you know, I do all my reading when I'm in the desert.

if u ask us for our advice and we give it to you ,you should take our advise . we are telling you that you cant keep it the way it is cause its not right and you will have big problems . it doesnt matter how much knowledge your friend has about turbos . you will never be able to tune it right with the wrong parts . do you even have a egt or wideband?

Think of it this way. With that much fuel being dumped into your cylinders, it washes away any lubricating engine oil.

Think about that over the next few days while you fucking your engine over. :)

Any one tell him that most injectors Are not designed for that kind of pressure?

Or that A Wankel is a totaly different beast?

Originally posted by Chamuko
Any one tell him that most injectors Are not designed for that kind of pressure? Or that A Wankel is a totaly different beast?

Originally posted by 97eclipse97
First off, you can not compare what a twin turbo RX-7 runs (when it comes turbo from the factory) and what your car does...

:-)

well not just that its turbo, but that its not an internal combustion 4 stroke piston engine?

Originally posted by Chamuko
well not just that its turbo, but that its not an internal combustion 4 stroke piston engine?

and it has primary and secondary injectors and blah blah blah.

This guy is a choad if he doesn't listen to any one here who knows what they're talking about.

Bro. I am in Iraq now and the car is sitting in a parking lot. I know I have to get a FMU but I dont know what brand to get. I have been listening to you guys, thats why I didnt drive it for the few days I had left in the states.

Could someone just caugh up a name or brand of FMU to get, and I'll get it.

vortech sfmu

I am severly limited on the sites I can visit over here. Is there anyway someone can give me a direct link to where I can buy it. My time on the computers is also limited. I cant get on Ebay either (its really fucking gay).

Hey man, just to let you know you already have a 12:1 FMU. But a SFMU is a nice upgrade.

you can get a vortech sfmu in the for sale section

Originally posted by boosted60trimrst
you can get a vortech sfmu in the for sale section

And I'll buy your 1:1 (if thats what is) for the right price. Think you can list the part number?

EDIT: reworded for "flow"

Originally posted by hs_elrod

Originally posted by boosted60trimrst you can get a vortech sfmu in the for sale section

And I'll buy your 1:1 (if it realy is one) for the right price. Think you can list the part number?

I got a nice 1:1 regulator on eBay, with gauge and all for $38 shipped brand new. I think the company was called BNR. Haven't used it yet so I'm not sure of its performance, but I'd be willing to bet it will work like the rest of them. I'll have it on soon with MS so I'll let you know. :D

Originally posted by DarkEclips96
Hey man, just to let you know you already have a 12:1 FMU. But a SFMU is a nice upgrade.

Sorry bro, but when I was trying to find out the problem of my fucked up idle, I took it apart and didnt know how to put it back to gether again.