Turbosmart will be the highest quality FPR available, lots of people opt for cheaper alternatives though. I went with a TS FPR2000 in my current build, despite having an aeromotive FPR on hand already.

https://adaptronicecu.com/blogs/articles/fuel-pressure-regs-is-there-much-of-a-difference

 

If you're adding an aftermarket FPR, my advice is to be careful where you mount it. I've seen too many RX-7's with single turbocharger exhaust housing blasting heat just a few inches from the FPR without any sort of heat shielding, that's a recipe for inconsistent fuel temperature (density) on a good day. On a bad day it's just a small fuel leak away from an engine fire. Also be mindful of engine movement, be sure there's enough slack in the fuel lines that reach from any chassis-mounted parts to any engine-mounted parts. I upgraded injectors and fuel rail on my car around 2008 when there weren't as many options available. I modified an Xcessive top-feed secondary fuel rail to add an aftermarket Honda-style direct-mount pressure regulator from AEM, and a fuel pressure sensor where the OEM fuel temp sensor would have been. ECU datalogs show fuel pressure and measured AFR/Lambda look good. The Radium Engineering secondary fuel rail and direct-mount FPR is a similar setup, I would get that unless there are other FD owners who have had problems with it.


I did some searching online and tuning shops advertise the 450 Liter/hour fuel pump as supporting over 700hp on piston cars, how much power are you planning to make in your RX-7? If your engine will never need that 550+hp worth of fuel, the bigger 450Liter/hour pump is going to be adding a lot of heat to your fuel compared to a 255 Liter/hour fuel pump. The stock FD fuel pump flows about 225 Liter/hour at 43psi fuel pressure according to Stealth 316 - Fuel Pump Upgrade Guide , probably less if using the factory wiring harness.

 

Thanks to you two,

So from what I can confirm on my side: it would be cheaper and smarter to swallow my pill and buy a weaker pump. Since I rewired thar Walbro 450 LPH fuel pump, is it going to be pretty much plug and play if I buy a Walbro 255 LPH? I'm definitely not planning to go over 400 whp.

 

Yeah that will be a super easy swap out. MAKE SURE to get the pump from a reliable vendor, not off Amazon or Ebay, tons of fakes out there. Banzai Racing and IRP are both good sources that have 100% pumps that are direct from Walbro.

Dale

 

"Thank you for your purchase!",

Now I've got to wait a couple of weeks... To be continued!

 

So I received the fuel pump. Unfortunately, I lost that plastic part which looks like a crown and Walbro didn't include it with the new hardware.. Instead of putting everything pictured (crown, o-ring, spacer), can I simply install a good old clamp there? Derwin installed my Walbro 450 LPH and that's what they did... It seemed fine to me!

 

You can use a hose and hose clamps to attach it. THE HOSE HAS TO BE RATED FOR FUEL SUBMERSION. If not it will turn to goo in short order. You do have to cut the "bell" off that the O-ring attaches to.

Personally I do like to use the OEM style O-ring attachment.

Dale

 

Alright, thanks.

Walbro 255 LPH installed. Fuel pressure finally seems normal. It runs rough, smokes, and at 850 RPM: 10 inhHg. I'm suspecting bad spark plugs (yes, again!). Do you think a fouled spark plug could cause low vacuum? I mean: if one of both rotors is flooded, then the compression is lower because the rotor housing is "too clean"? Could I be right?

 

Vacuum is pretty linked to engine compression. Most likely the engine is just so damn new it hasn't had time to build compression up.

If possible, drive it around a bit and get some heat in the engine, more than just sitting and idling or even revving. That's the best thing for fouled plugs and engines trying to build compression, get some real heat in it.

Dale

 

Well I'm getting kind of desperate here...

I'm chasing that same problem since over a year: blue smoke out of the exhaust. I bought a brand new turbo because at first I thought it was the problem, without any change.

I installed (again) 4 new spark plugs today. It seems like vacuum might be a bit better, but still that blue smoke. Maybe 2 miles on the engine, (yes, 2), but about 3 hours of idling already.

It seems to be running OK if I press the throttle at about 30%, but once I go more than 30% it runs pretty bad. Smoke also seems to be worst at higher throttle %.

I would really love that blue smoke to go away. Could it simply be too much 2-stroke oil in gas (I'm premixing and fuel level in the tank is low)?

Oh and... following someone's advice here, I have removed the PCV valve: top port on filler neck is capped, bottom port open in the air. UIM port capped.

Thanks!

 

Dude, who told you to take pcv out? BAD IDEA. You have pressure building up that has to go somewhere.. and you know where it's going? The pressure is relieving itself through your turbo and dumping **** tons of oil in your hot exhaust. Nastiness.

1. Put your valve back on.
2. Get rid of caps and route to intake.
3. Bye bye smoke.

Question: Are you running stock ECU?

 

^We addressed that a while back, he has 1 port open to atmosphere so the PCV system isn't to blame here.

Murci, I think at this point you need to drive the car some and get some mileage on it. New rebuilds can smoke a bit. Get some heat in the engine and everything. Just a nice easy drive around the neighborhood for 15-20 minutes, do that a few times and see how it does.

Dale

 

In some cases it does matter. He may have to take advantage of the vacuum. I'm not sure how big the OPs hose is if venting to atm.. Could be too small leaving him with a positive pressure needing to be relieved.

Instead of explaing ourselves, we must consider that the needed work to test this is minimal... for an rx7 lol.

I'll say this, there's been plenty of good info given to you in this thread and ... well, not sure what to say.

Stop thinking and start deducing.

Put the valve back on and route accordingly. If your problem persists then your build is the issue and you have to tear down, making sure oil seal springs are properly installed. Obviously inspect turbo before getting crazy.

Now I'll say this, not sure what you mean by smoke. It's one of those things that never translates well in words haha. If you're driving and the smoke is thick as hell when you press peddle past cruise position, and it definitely smells like MOTOR OIL, not 2 stroke(they smell quite different), then I would say the PCV omission is the culprit.

Like I said, minimal work, don't think, just act, and you will know FOR SURE because, if you still blow smoke then there's only one other culprit. And just hope that you don't fall into the 10% category lol.... but seriously, not funny.

 

I'd like to add that I really don't know if you're actually driving the car. I mean, you need the car on the road you know? If you aren't putting any clicks on the engine then you're kinda working against yourself. That engine simply doesn't like being on an off with no load in between, it gets dirty and really freaking cranky.

 

You guys are right that I should start doing some more tests before asking questions. Installing or removing PCV setup isn't complicated.

I'm confident that the oil seal springs are installed properly.

I went for a longer ride to put some fuel (about 10 miles total). When I came back home at idle, it was still smoking blue. I removed the air filter today and no oil seems to be leaking from the turbo.

My question here: when I look at that single turbo diagram, I do not have that blue line (purge control, catch tank, charcoal canister). I do not understand its purpose either. What do you think?

 

The blue line is the vent for the gas tank. Gas tanks build up flammable fumes so they are trapped in the charcoal canister in the back of the car then the solenoid releases them to the intake manifold to be burned.

Blue smoke 9 times out of 10 is a turbo issue or PCV issue. With single turbos sometimes it can be having the wrong size feed or return - too much oil in the turbo that leaks into the exhaust. With stock twins it's a bad seal in the turbos.

Dale

 

You're doing it again man.

This is what you were supposed to write:

"I put the PCV valve back in and my smoke went away." OR "I put the PCV valve back in and the smoke didn't go away."

We could keep writing love letters if you want.

PUT THE THE VALVE BACK IN AND THEN POST RESULTS.

Man I miss the old days, when people actually took the advice and then posted results and if you didn't someone would call you out and tell you to stop wasting our time.

I'll add that maybe you're too confident. Humility is part of the rx7 journey, be humble and you might actually learn something.

 

Went for a 22 miles ride - no change, it still smokes. Initial startup smoke, cold to warm, doesn't SEEM to smoke (I stopped twice and couldn't see any smoke), once warmed up it definitely smoked.

Afterwards, I searched and couldn't find where that bottom nipple on the oil filler neck was going, so I decided to install the Jaz oil catch tank: UIM nipple capped off, filler neck nipples both to the oil catch tank: it is still smoking.

Turbo is brand new.

Lots of stuff are brand new.

I have spent a LOT of money to get that car running. Now it is running but it is smoking blue. I'm getting desperate. I know that I installed that engine properly.

 

Next thing I would be suspicious of is the turbo oil feed and return. With an aftermarket turbo the oil feed and drain have to be JUST right to give the turbo enough oil. If the turbo get supplied too much oil it smokes, if the drain isn't large enough or sloped properly it backs up and smokes

I know some people have had to use oil restrictors in the oil inlet to keep the turbo from smoking.

This may be a good thread for the single turbo forum, have them check your work on those lines.

Dale

 

I'm trying to help you. You seem frustrated. I am also frustrated haha.

Can you do me a courtesy? I feel you owe me this much.

Can you go out in your garage and locate your PVC valve?

Then delete your catch can, I know I know, the catch can looks cool, I get it, Delete it. Don't take it out of the car. Just delete the function.

Now hook up the PCV valve up by installing the light blue and orange lines in the diagram you posted.

That shouldn't take too long.

Now go for a drive.

BIG QUESTION: IS THE SMOKE GONE? Yes or No, this is very important to deduce.

If you post another diagram I'm gonna do a freakin' somersault into my compost pile.

 

I'm really trying to stress the importance of KNOWING whether or not the PVC omission is causing your issue. If you don't do this test then you don't deduce anything. We NEED a Yes or No to help you.

 

I haven't run a PCV valve in years and have eliminated them on most cars I've worked on. 95's don't have them at all.

The crankcase just needs to breathe. As long as it's not capped up it's good.

You can also eliminate this by driving with the oil cap off to be certain which I know he did ages ago.

Dale

 

I sent a message to Turbosource last week and they confirmed that no restrictor is required with a S362 SX-E. I used the same drain line that I had before. But yes, you are right, at first I thought something could we wrong there...


I do not like to say what I'm about to say:

I searched. I cannot find where the bottom nipple is going, even with the diagram I included it is not really clear. That bottom nipple has to go back to the UIM???

I'll try to drive with the oil cap off.

Thanks everyone for your help. Yes I am mad at the moment, but it is at myself. I'm starting to realize that at this point, this car will probably have to get to Derwin Tuning via a tow truck.

 

Alright, evening update. Less talk, more tests!

1. Still haven't tried to install that PCV valve. I do not know where that bottom nipple on the oil filler neck would go.
2. Removed the oil catch tank, capped the top nipple and vented the bottom nipple. Also removed the oil cap. I went for a 5 miles drive, the smoke *could* be lighter (but it was darker outside too so harder to judge) and there is constant very light smoke coming out of the oil filler neck.
3. Oil level doesn't seem to go down.

I would like to eliminate the "I put too much 2-stroke oil in my gas tank" theory. Tank is currently at 40%. Would it be dangerous to drive for a short period of time with no premix, considering that I've got no OMP? Just for testing purposes...

 

It seems the more we test the . ( The father of this problem) the more problems we have. I think the guy that had the car before us put in the wrong injectors is there a way we can tell if they're the correct ones or not?