quick fuel system question

[sLoWnStEaDy]

Hey all, i am getting ready to finaly do some more work on the RX7 after taking a brake to get the fiero all buttoned up (still needs aligned and i should be painting it in the next couple weeks or so)

Anyways. I did a SBF swap in case you missed it. Now i have a Holley "blue" fuel pump with all the 3/8" line i need to run run it up to the engine compartment , along with a FPR, and a fuel pressure safety switch that came with the nitrous kit i purchased. I am tryin to decide if i should use that for the nitrous, the carb or both. I would also like to point out that i have never dealt with a fuel system other than replacing injectors, pumps etc...
here are the 3 ideas i have for the fuel system:

1: use the factory fuel pump and fuel line along with a 4-port FPR to feed the carb abd use the factory return line... well... for the return line. Then have a fitting on the gas tank for the for the AN fitting and use the Holley pump and FPR and safety switch for the fuel selenoid on the nitrous system


2: use the factory fuel pump and fuel line along with a 4-port FPR to feed the fuel selenoid on the nitrous system and use the factory return line... well... for the return line. Then have a fitting on the gas tank for the for the AN fitting and use the Holley pump and FPR and safety switch for the carb.


3: Dont use the factory fuel system at all, have the fitting on the tank for the holley pump/line then just split it under the hood to feed the carb and the fuel selenoid. My only worry about that is i was told it would be much better to run a 1/2" line all the way to the engine bay then split to a pair of 3/8" lines.

[Scott]

it really depends on the power your making and how big of a shot your running, with a 150 shot you would probably be ok with just the one blue pump. Ideally you would want two fuel systems. but I would at least run 2 fpr, just the standard holley regulators that come with the pump are actually the best ones to use with the nitrous system. just dead head both regulators "no return line" the 3/8 line would probably work but 1/2 would be ideal. run a Y block into the regulators and make sure you set the fuel pressure flowing thorugh the same size jet you plan on running and pull out timing according..

[sLoWnStEaDy]

sweet, thanks for the reply! ill do that for now, then when i put my 408 in i will get another complete setup and run an additional fuel cell for the nitrous.

[DustinsDuster]

see, i just took a feed off of the feed line running to the front float bowl on my carburetor for the fuel selinoid. but then again, i have an A1000 fuel pump, 10an feed line to the regulator, two 8an lines feeding the carburetor and an 8an return line, so i guess i could get away with more than you could with that Holley blue pump.

my biggest concern would be about the factory fuel pump supplying enough fuel for that thirsty 5.0L

[sLoWnStEaDy]

my biggest concern would be about the factory fuel pump supplying enough fuel for that thirsty 5.0L

I was wondering about that, the stock pump flows 160LPH i figured that would be enough for the fuel selenoid but i have never messed with nitrous so i really have no clue. Also i am not 100% sure what size all the fittings i have are. The person i got it from pulled the fuel system off of his 466 powered camaro and i gave it all to me (well i traded him my ebay twin turbos, WGs, adn BOV) So i fugred if it was enough for a 466 it should be plenty for my 302.

[DustinsDuster]

was it a carbureted 466? your 302 is fuel injected, isnt it? if so, that Blue pump wont push the fuel pressure needed for fuel injection.

[Scott]

yeah what setup is this, throw a little more information about your setup.

[sLoWnStEaDy]

sorry. The engine is a 1988 5.0HO but it has been converted to carb. I know i am pushing it a bit with that much nitrous, but the weak points are my block and trans. I have talked to a ton of peopel and they said sa long as the car is tuned properly it can take a 200 shot all day every day for quite a while.

-got rid of the A/C
-got rid of the PS
-BBK underdrive pulleys
-dual remote mount oil filter kit with twin WIX filters
-hooked up to the factory RX7 oil cooler (23" X 5" X 2.5")
-NOS wet nitrous system, 150-200 shot (cheater kit up to 300 shot)
-Fox body long tube headers (1 5/8" with 3" collectors)
-dual 3" exhaust from headers back to an x-pipe then out a mindtrain 2.5" dual "catback" exhaust
-gasket matched and polished heads(E7TE) and intake(torquer)
-ROL "race" head gaskets
-MSD 6-BTM, Pro Comp HEI coil, and a 50K HEI dist
-Holley 600CFM carb

[sLoWnStEaDy]

Also that is pretty muh just a temporary setup as i stated i am going to be building a 500HP N/A 408 that will be going in either this winter or next spring depending on how things go. I think i will also be ditching the T-5 transmission and going with a strong auto trans.

[Scott]

with that stock bottom end I would probably stick with the 150 shot if your going to spray it alot just to be safe.. any of the 4 corner cylinder's on fords that run a carb plate nitrous kit tend to run lean anyway, so I would at least suggest having 2 regulators so you can have a dedicated nitrous one, run a fuel pressure gauge in addition to the fp safety switch where you can see it and keep tabs on you fuel pressure while the nitrous is on. and that fuel system should be able to handle it. If you can use your stock fuel system to run the motor and use the holley for the nitrous that would be the way to go!! dont forget you should be pulling 6-8 degree's out with that shot, along with one step colder plugs ideally.. sounds like it should be one hell of a ride. from prior experience you should definetly take your time when shifting, and dont try a 5500 rpm nitrous launch with slicks and maybe that trans will hold out for a while..

[sLoWnStEaDy]

If you can use your stock fuel system to run the motor and use the holley for the nitrous that would be the way to go!!

well, the stock pump puts out 160LPH but is a high pressure F.I. system so i would have to run a 4-port FPR correct? If the 160LPH is enough and i just have to regulate it then i can have that all done and buttoned up in no time, all i would need to do is buy another FPR. let me know what you think

[Scott]

that would be a good way to set it up, the problem would be the regulator, to the best of my knowledge a bypass style regulator designed to step-down pressure that much "like a aeromotive" costs as much as a holley blue pump that comes with its own regulator. that would be up to you as I dont have much experience with those high pressure efi pumps running carbs, but I can tell you that the holley pumps and regulators are very reliable and provide steady pressure. They would also be capable of fueling your 408 as well, then use that same plate kit on the 408 and if the combination works well you will have a good 9sec car on your hands. one other thing I would recomend if your going to get into this carb and nitrous stuff is getting a book on reading spark plugs, that could save you some burnt parts.. I know dustins duster is running a high pressure efi pump stepped down for the carb but he's got one of those high dollar regulators on there too

http://www.aeromotiveinc.com/tdetail.php?tip=63

[DustinsDuster]

if you just need another Holley 3 port regulator, i have one with AN fittings on it i wil sell for $20.

[sLoWnStEaDy]

wow, just looked for a blue pump with reg. on ebay and it looks like i can get the pump and reg for under $100, so i will just go that route and buy another pump and reg so I dont have to worry about it at all...

[Scott]

good idea in my opinion :bigthumb: use relays

[GMPARTSMAN]

if you need a blue pump i have 1.. works great $50

[Rollin on Dubs]

I have a holley Big port regulator i would sell, for $40 or i think i have a basic holley reg (what comes with a blue pump) i would sell for $10


Big-Port Regulator
Die cast aluminum regulator is adjustable from 4-1/2 to 9 psi. Designed with one 1/2'' NPT inlet port and two 1/2'' NPT outlet ports with minimal flow restrictions. Includes mounting hardware. The least restrictive, highest flowing production regulator for a single 4-bbl system - race or street.

[Rollin on Dubs]

[quote="Scott";p="130672":c9d12]If you can use your stock fuel system to run the motor and use the holley for the nitrous that would be the way to go!!

well, the stock pump puts out 160LPH but is a high pressure F.I. system so i would have to run a 4-port FPR correct? If the 160LPH is enough and i just have to regulate it then i can have that all done and buttoned up in no time, all i would need to do is buy another FPR. let me know what you think[/quote:c9d12]

If you do go that route, A Mallory 4309 would be a somewhat cheap alternative, $80 or so and you can have a diapram bypass regulator. that is just as good if not better than that aeromotive one scott pointed out. They do the same thing, just the aeromotive one has bling!

[sLoWnStEaDy]

or i think i have a basic holley reg (what comes with a blue pump) i would sell for $10
If you habe that for sure, LMK i will take it!



if you need a blue pump i have 1.. works great $50

I am for sure interested in this as well, but do not know for sure if i can buy it quite yet or not. If i can, i will have th emoney this weeked, i will PM you and let you know. since you are a GMPARTSMAN, would you have any use for a complete set of FelPro head bolts for a SBC (still brand new in boxes)