When it comes to fuel supply, I'm lost. I now nothing of injector flow rates, duty cycles, FPR's, fuel pump flow rates, and how you calculate what is needed for a certain hp. I think this is something for the FD that doesn't get enough attention. There are so many setups that I've seen. One fuel pump or two, additional injectors or not, custom fuel rail or modified stock one, in-line fuel pump or in-tank, bigger supply and return lines, adjustable FPR or boost dependant? Then you've got the ignition factor which plays another huge role in this. Stock coils or aftermarket, ignition amplifier or not? There has got to be one way of seting up a fuel system that is superior to the rest. I'm looking to produce 500hp. I think I'll need 850 primaries and 1600 secondaries, probably two fuel pumps, and a different FPR. Anyone out there who really knows what they're talking about when it comes to fuel systems? Thanks.

 

Seems like people go overboard on fueling alot on this board.

550 primaries (stock)
+ 1300 secondaries (drop in - still in the stock rail)
+ Adjustable fuel pressure regulator set at 49 psi base
+ One Walbro 255HP pump with a 10 gauge power system straight off the battery or alternator

= 500 flywheel HP at 80% IDC at 0.6 BSFC (likely) & 86.3% IDC at 0.65 BSFC (unlikely)

Now watch...somebody is going to come in here and reccomend something nutty like 1000cc primaries, 1680cc secondaries, and dual pumps just because it sounds cool and "you might need it later."

 

http://www.maxcooper.com/rx7/how-to/...tem/calcs.html

 

According to the calculator provided by the above post, your setup would equate to 423hp at the wheels. I wonder how accurate that calculator is.

 

423rwhp ~ 497hp

I did what Trevor recommended against.

upgraded secondary rail with 1680cc injectors (removed ACV)
Modded primary for AN fittings with 550cc injectors (removed OMP)
FPR base 40psi

~71% duty cycle at 17psi of boost. which by the calculator I'm making in the ball park of 480hp

 

people get topfeed 1680 secondaries because they are cheap...

 

and you'll never have to upgrade fuel again...I don't have any plans for 550rwhp

 

I forgot what the ACV is an what is does. Air Control Valve maybe? Just wondering what affect removing the Oil Metering Pump has on your primary injectors. And is that an aftermarket FPR set to 40 psi? Thanks.

 

HUH?

The OMP supplies lubricating/cooling oil to the interior of the motor....and has nothing whatsover to do with the primary injectors. One things' for sure, if you remove the OMP, you won't NEED an upgraded fuel system.....

 

no, but you do have to remove the OMP nozzles to fit AN fittings on the primary rail...I didn't explain that well, sorry for the confusion.

ACV is the secondary air injection for the air pump/emissions...sometimes port air gets sent to the air pump. I forget all the specifics now.

here is the only pic I could find, showing both...


I didn't really want the OMP lubricating my motor anyway...since I was going to be pushing a lot more air than stock.

 

Ok, thanks for explaining the OMP thing. I was wondering how the injectors had anything to do with that. I have a block-off plate kit that I never installed. Doesn't that include one for the ACV? Also, I will be removing the OMP and running pre-mix. I believe in eliminating all possible points of failure and excess bs. Try and get it as simple as possible.

 

sometimes...its a very trianglular looking plate...I had to order it separate.

it's a good idea to remove, especially if you are aiming for 500hp.

 

Anyone got any better pics of the fuel system setup. eg.Kgparts fuel setup?

 

jake, you be crazy

 

Actually, if you use 45 degree fittings you there is no need to remove the OMP nozzles.

 

Any more pics?

 

If you're asking me, there are a few here:

http://dave.newbern.org/gallery/album01?page=7

though you can't see much of the plumbing of the primaries or the OMP jets.