SleeperZ

But they SAY 43 gph at 40 psi. That's the first time I've seen an actual graph of the output of that pump, and it's not as bad as I thought. I used the Bosch pump off a Saab Turbo, paid $12 for it, and it flows the same.

Problem is the MSD pump is not good for high pressures such as a boosted L28. How much hp at what boost pressure do you want to support? That answer will dictate your new pump specifications.

Stony, if you start breaking solid rears, I'm gonna start to worry about you.

Turbos on the Z32 are parallel, like a typical twin setup found on a V8, with one cylinder bank feeding one turbo. This is done for plumbing ease, and will not spool as fast as an equivalently flowing single turbo. I'm not familiar with the stock MKIV Supra setup, but I believe they have some sort of trick controller that spools the smaller turbo first, then opens the big one. I don't know how the plumbing is done at all. As you know, one of the better upgrades for the Supra is a big single turbo.

Triples and a high hp n/a motor has no comparison with fuel mileage. My setup gets me 27mpg, cruising 80-90 mph. Of course, at my altitude, the n/a motor can't keep up anyway.

Ahh, that's what I don't like about speed-density standalone FI systems. Change anything, and it's time to retune. Of course JeffP is still running a JWT? What's up with that? The ECU should just measure the air and meter the fuel..?

All earth orbits will eventually decay, but not because of the distance from earth, but because the vacuum isn't perfect, and friction eventually slows the satellites down enough to spiral in.

That MSD pump will run out of flow way too early. Try the Bosch application for Porsche Turbo or Delorean, or even Saab turbo. They used CIS (very high pressure) so they are suited for flowing well at the lower fuel pressure of the Zs. There are lots of numbers, but all the above applications will work.

I made a custom turbo inlet pipe so I could recirculate. It's totally quiet.

Don't know if you've read any of my other recent posts, but I highly recommend the Bosch pump as the foundation of any highly boosted Z. From what others say, the RRFPR is useful on an otherwise stock 280ZXT, where you've maxxed out the AFM with stock injectors. You still need a high pressure pump. And I support Yo2001's comment on "wideband and dyno" because you never know what you're going to get blindly tuning a RRFPR.

hehehe

I would maintain there certainly is no point to using a RRFPR with a properly functioning Z31 EFI system. What is needed is a constant fuel pressure, as the internal fuel maps in a Z31, including JWT, are all based on it. And I don't mean constant without a manifold reference, in fact it is the manifold reference that ensures a constant fuel pressure to the injectors under all operating conditions of cruising and boost.

I tested the stocker at 95 liters/hour with 50 psi head. The Bosch will flow a minimum of 60% more at the same pressure. IMHO, there is no reason EVER to replace a stock pump with another stock pump.

I had my P90 re-built with the MSA stage II turbo cam. My builder was going to put a larger exhaust valve in it. He did not because, according to his flow bench testing, the small bore of the stock L28ET restricts the flow of the larger valve. He found the stock sized exhaust valve, accompanied with some unshrouding, outflowed a larger (2mm larger?) valve. A bigger valve would certainly make sense in an overbored engine though.

In that case, it is not an ignition module, it's the CAS. It's bad, the car will not run AT ALL.

Ask him if he has any pictures. As the auction is, I bet he won't get a single bid. That's a lot of money for a used NISMO clutch-type LSD, if that's even what it is.

If it doesn't have a second diaphragm, there is no way it will have a non-linear rise of pressure with boost. That is why the RRFPR units are connected into the regular FPR on the return line with a second boost reference - to gradually restrict fuel return based on a second separately adjustable boost reference.

I run mine at about 1000. Seems like it takes less time to rev to boost setting it high. (Actually I haven't ever adjusted it down after passing emissions testing.)

Interesting. Confronted with that data, I'd be tempted to swap ECUs to see if they both react the same to the TPS and initial timing. It almost seems you may have a fault in an input signal inside the ECU possibly causing some noise. Either the temp sensor or the TPS. Of course, check all the electrical connections for broken or fraying wires, etc... Interesting about how the timing curves are different for idle mode and cruising mode. I didn't expect to hear the timing changes much with RPM under idle. WOOOOOOO!!! My 2000th post!

If that intercooler is dropping 1-1.5 psi at the stock hp level of 300hp (I know, I'm generous) that means at 600+ hp, that unit is dropping 4 to 6 psi. That is not good. I think 2 in parallel would work well - it's a popular GN IC upgrade to extend the endtanks lower to the ground - not sure they get more than 4-6 inches, but every little bit helps.

If it's very consistent like that, always coming back OK after being unpowered, it could be a code problem. As far as another possible cause, my car ran like crap when I had some plug wires die on me. It happened suddenly, one minute fine, then the next, awful. But it never recovered, even after unplugging. I ended up switching to a Z31 ECU, only to have the same problem still!