Jean, I know you are knowledgeable member of several forums, and there was more indepth info you had that you did not state. That was my way to get it out of you thanks.

However, I still fail to see how these pumps are not flowing enough, yet so many cars are pushing verified numbers much higher? It isn't just one or two cars, pretty much all K24/18's with injectors are pushing way more than the numbers say they should....

 

I suspect that at least part of this is duty cycle. Jean is using 85% which is a common max number for injectors to prevent overheating. I suspect that many folks are running them a good bit past 85% for starters and that fuel pressure is also being bumped. It would be interesting to know what an OEM injector flows at 5BAR - and no the increase will not be linear!

I had ASSumed from my reading here that the OEM pump was an 044 - no? If not is the 044 a direct drop in replacement for some higher capacity? One thing puzzling me, in the Supra world companies advertised and sold fuel solutions - I could go to their sites and see the aprts to know what I was getting. In this "world" I hear about solutions often secondhand via word of mouth on forums and cannot find them on sites for sale. Do any of the folks offering fuel systems for sale for this car offer them for the DIY kind of job or is it expected I'll have a favorite shop supply me with everything? I mean really a hanger for a second pump, a pump, plumbing in the tank maybe, and some wiring seems like it would be fairly easy to drop into the tank like we did with Supra. So long as the OEM fuel line is suffeciently sized and the FPR can return the higher volume of fuel at idle it seems like many of us would be golden. Here's an example that Titan sells -> http://www.titanmotorsports.com/cncfuha2or3p.html I put something cheaper but VERY similiar into my Supra and was good to go on the supply end of things. Is there any reason why the 996 cannot do much the same?

Sorry to the OP, this isn't Camaro stuff but honestly this is also pretty much exactly what I was thinking for your SBC - fuel is fuel! However dual fuel lines or at least multiple feed would probably be a good idea to consider in your case as you aren't dealing with OEM restrictions obviously. Hopefully the 996 system doesn't starve the furthest injector eaither...

 

Prche951

Thanks, Haven't been on the forums for a while.

I think I have written this somewhere before..Running a 996TT with stock 44lb injectors and a stock FPR (3.8Bar), your car will have "approximately" the following numbers:

@85% duty cycle: 460 FWHP
@90% Duty Cycle: 486 FWHP

If you move to a 5 Bar FPR with stock injectors then you get:

@85% duty cycle: 526 FWHP
@90% Duty Cycle: 557 FWHP

If you move to a 5 Bar FPR and 60lbs injectors you get:

@85% duty cycle: 556 FWHP
@90% Duty Cycle: 589 FWHP

And you have to check whether your fuel pump can keep up by measuring as before its flow rate and divide by BSFC...

BLKMGK is right, you can run at 90% duty cycle (I do) or more, only it is not really safe or recommended from an AFR stability perspective unless you have a state of the art custom program (on an engine dyno) and a great ECU like Motronic to protect you.

The Hybrid turbos will not improve efficiency on your engine, meaning , they will not improve the HP that you can get from one lb of fuel per hour, they can hold better efficiency levels at higher RPMs or boost levels, but that is not related to engine efficiency per se.

Things like head work, twin plug, compression and better breathing can get you anywhere from 5-15% improvement on engine efficiency perhaps...a bit optimistic.

Anything beyond this is dyno related I guess.

 

No apologies needed. That's why I brought it up in this section. This is good discussion and good info for me as I have both cars.

 

This is very good information. Now I'd like to hear from the tuners and how they squeeze more power than this with stock fuel pump. Because they all do.

 

Surprised that we haven't heard from any tuners and their experiences.

 

Trade secrets? I'm sure when I get bored and call my tuner and say "what's my next step", it will be "an 044 pump".

 

I agree. One of the reasons I posted this in the 996TT section.

I hope to be calling your tuner soon too.

 

You won't be disappointed...