imported_BoOsTd

Ok, I know the physical differences between the two, the AFC being an electronic controll and the FPR being a manual controll...

I havent gone to this stage of the game yet with my engine, so im not compleatly 100% informed on this subject yet, hence the reason im asking...

However this is going to be my next engine mod, because eaither the FPR or AFC will be able to be swaped over to my new engine when the time comes, so its not like im wasteing money on this engine. I have the intake exhaust, MSD, now its time for fuel tuneing



So my question being, do they ultimatly accomplish the same thing? Like is the AFC just a fuel pressure regulator thats easily adjusted in the cockpit, with a fancy electronic display?

Or is it more (besides the vtec controll) or does it do something completely different

and if it is the same function, why do people run AFC and an adjustable FPR?? isnt that just a waste of money buying an FPR if you already have an AFC??


Feel free to fill me in

HAPPY

Well, one of the major differences is price... but that aside.

a FPR is basically just going to bump the pressure of the fuel. You can not really tune on a FPR other than making sure the entire band is not lean.

An AFC is a tuning tool that allows you to add and remove fuel at different RPM intervals. Therefore, you can tune your whole RPM band to a specific A/R ratio. Theoretically, if thuned, this will result in more power.

bbarbulo

iTrader: (2)

depends on your application.

an FPR delivers more fuel by increasing pressure at the injectors... to the point where something will blow or the injectors will stick open

an AFC delivers more fuel by keeping the injectors open longer under stock pressure, so it's more reliable (up to about 80% duty cycle, which is likely when an injector becomes pretty unreliable and it's time for bigger injectors).

if you have bigger injectors then an FPR can't do **** for idle control, you're just gonna be seeping fuel from your exhaust. an AFC can open them for a shorter time to return to stock volume and pressure.

AFC > FPR

however, if you have LIMITED short time bursts of speed, then the FPR may be sufficient since you don't ask for prolongued periods of time where the injectors are overworking themselves.

imported_BoOsTd

right ok, so the AFC if tuned right it is going to give you better highway cruising fuel milage (lean side)? but will also produce the fuel needed for power, when your really hammering on it?

AFC seems like a waste of money for me i guess, I dont have turbo, I dont have vtec for a VAFC, and my next engine wont either (well maybe someday if i do a head swap..) but i am running nitrous, (but has its own pressure bump to make the mixture anyway) so i dont see the point of spending the cash on it.

Im thinking of just sticking to the FPR route. Unless somone can show me its worth it for my application.

and still, why would somone run both AFC and FPR

bbarbulo

iTrader: (2)

it's not worth it until you go bigger injectors

I dunno, AFC and FPR is pretty stupid, it would confuse the hell out of your tuning. I mean, you hammer on it, the AFC widens the pulsewidth, the the FPR bumps pressure and you're flooding your motor with like 80 psi of fuel pressure and like 65% duty cycle No... there is no reason to do something like that unless you run smallish injectors for emissions reasons and need the extra pressure up high.

Personally at that point, I'd go standalone.

imported_BoOsTd

I hope Gallager reads this, so he can sell me his FPR

bbarbulo

iTrader: (2)

but his FPR is just a B&M unit, it's not boost dependent - right?

I have a B&M too... just so I can regulate pressure on a high volume pump. Which was stupid of me - the B&M uses stock regulator internals, so the flow rate of the return system remain unchanged. Duh! Oh well, it's eye candy... to bad they didn't have silver in stock

imported_gatherer

if you go past the 80 duty cycle it's like leaving them open .. they start acting like valves would at high RPM and sticking open .. or floating .....

other then that if done right a AFC is a good way to tune... if done in conjunction with bigger injectors and higher fuel pressure (not beyond what the injectors are rated for) you can dump a ton of extra fuel in ... of course you'd want to optimize this ...but you get a wider range to play with

imported_BoOsTd

All the B&M honda units are the same, so boost dependent i dont know, whatever it says on your packageing lol...

Well i just picked up a new 255 GPH pump, is a B&M gonna be no good for me? THis is the main reason im looking into the fuel tuning right now, i want to make the most out of my pump and airflow.

I dont have any planns for bigger injectors either, I dont think i really need them with just a 65-75 shot of nitrous ( im not running big cams or intake manifold...) ... so the return rate really isnt a concern to me right? 255gph shouldnt need a bigger return flow right? or does it...

bbarbulo

iTrader: (2)

255 gallons per hour????? what did you buy a swim pool pump LOL

255 liters per hour I think, right?

I dunno much about nitrous, but anytime you start talking crazy talk like 75 shot of N2O methinx 310 cc injectors. They'll run like stock until you open the N2O assault, when they'll sufficiently feed the fire. But I mean it all depends on if you're using a dry or wet system and so on. Dry, you gotta worry about your own fuel, wet systems bring their own fuel to the party at least that's how I understand it.

imported_BoOsTd

haha yah LPH i ment! wait no i bought a firetruck pump lol haha you know what i ment


Will the B&M FPR be suficiant fuel tuneing tho for this application?

255lph pump,IHE,MSD, and (injectors possibly) reason i ask is cuz I hear you talking about the flow rate of the return system not being quick enough, so im assuming your useing a bigger pump than me for your turbo??










actually I just did some more reading, im starting to think I should upgrade my injectors for extra safety... (they can allso be handed down to my new motor when i do the swap)



this is off ZEX website


Do I need to upgrade my fuel kit to use your kit?

Our kit was designed and tested for use with stock fuel kits. It will perform properly on stock and mildly modified engines, i.e. header, K&N filter, exhaust, etc. If major modifications have been performed, i.e. camshafts, heads, porting work, intake manifolds, etc. It is strongly recommended that a fuel pump and injector upgrade be performed on your engine before using your ZEX nitrous kit.

bbarbulo

iTrader: (2)

I have a 255 Holley HP pump. I'm just saying, the B&M is as good as stock for me... since I won't be adjusting fuel pressure. I just wanted stock fuel pressure, which I should be able to get with a stock FPR. But since I already hacked mine I'll leave it.

They don't make a bigger intank that mine BTW... that's as big as they get.

No, the B&M will not be sufficient for what you're doing. As a matter of fact, I dunno any case where the B&M is sufficient? It can raise or lower pressure... so yeah, it has some purpose, but for anyone who is not N/A it's as good as useless. I mean, it works... but if you have good tuning from the computer you should never need to touch it! Know what I mean? What you need is a solenoid that will turn up pressure when the N2O comes online. So when you switch the nitrous on, this solenoid should turn up the pressure in preparation for the nitrous. But again... if you buy a full kit and install it as per instructions, you should be okay with a fuel pump. Then as you learn more about how it works, you can start toying with it and so on.

imported_BoOsTd

yah the zex nitrous managment unit already bumps the fuel pressure under nitrous (its connected to my vacuum system, so it bumps the pressure underspary for consistant mixtures), thats one of the reasons i went with it, less dicking around... thats why all they reccomend is fuel pump and injectors and ignition retard.(for the 75 shot) 55 shot is fine on stock everything like i have setup now

hmm ignition (another topic) methods of retarding ignition 2degrees...lol

but what I want now is more power when im not spraying, just pure na performance, cuz obviously the spray only gets used on special occasions. The rest of the time im purely N/A, thats why im considering a B&M for daily use. would it not be sufficiant for adding that little bit of extra fuel to a IHE setup?

bbarbulo

iTrader: (2)

yeah, you could bump the press with the B&M, but then you need dyno time to figure out optimal pressure.

imported_BoOsTd

yah tru that, i figured i would just set it to OEM pressure, and then increase it a few psi at a time, drive it for a few days, then try alittle more, checking pluggs ect for flooding.. not very efficiant way but 5-10 extra psi ontop of stock, will def be some sort of gains i figure...... basically trial and error.... and maybe set it back to OEM pressure for longdistance trips to save fuel milage.




Do you know if the h22 uses the same B&M as b/d series? theres a guy in clasifides with a B&M off an h22, wonder if it will fit my car.


*cough* unless Gallager sells me his, cuz he doesnt need it cough*

bbarbulo

iTrader: (2)

we used a H22A fuel press reg on a 93 Si Civic... it worked okay. We fuct the stock Civic one drilling holes in it LOL

imported_BoOsTd

so they are interchangeable? I figured worst case i can dissasemble it, and mount it on my OEM FPR as long as its the same unit that b/d series uses...


and may i ask WTF u were drilling holes in that reg for? hahah

bbarbulo

iTrader: (2)

interchangable to the D16Z6, dunno about the Y7/Y8.

yeah, sure you can there is a trick to drill a small hole in order to aid on higher flow to the return line in the case of having a high flow pump like a 255. well the car we did it on has a stock pump so it would barely hold any pressure

we did one on a 255 eq't car and it works fine, except for slightly longer crank times now... the prime isn't as good as with the unmodded reg.

the trick is off endyn BTW

dingus88

ok here is the deal...fpr is just a tool to raise the fuel pressure and that is it..not tuning nothing..

the afc is a "computer" that tricks the ecu into leanign or dumping more fuel in 500 rpm increments, this is what you want and not a fpr

310 injectors woudl flood the motor so badly you woudl wash teh rings out wiht out a afc to tune it...you don't need to upgrade teh injectors to get a afc it would be very good wiht jsut i/h/e cause teh stock fuel curve generally is more lean and promotes fuel economy mroe than raw more so richening up the curve woudl be good for hp

a walboro 255 is way over kill it will support almost 400 hp and will probobly over run your stock fpr wiht all the fuel it is pushing a walboro 190 would be mroe than enough

basically what are you guys runnign here so I can give better advise

are you guy's runingn nitrious wet/dry or all motor turbo...??? mroe info is needed here

speedemon

the point behind drilling the regulator is to get fuel out quicker if your running a high volume pump
if your not then you have super low pressure and when your idle goes up your pressure decreases untill you get a pump
thanks B