do i need a FPR ?????

[DSMJim]

You just explained why you do need one.

You can't tune out the problems from overrun with an SAFC. All you can do is bandage up the worst parts but it can't do anything about the regulator overrunning everytime you back off the throttle or that overrun isn't RPM based but load based. Within a set of NE points that the SAFC deals with your regulator could be online one second and overrunning another based solely on how much excess fuel the engine is consuming. Some of this is splitting hairs because the difference in fuel pressure can be minor but the whole FI system is designed around the idea that the fuel pressure tracks manifold pressure 1:1 without spikes and blobs in it's response from overrun.

The only fix to FPR overrun is a FPR that doesn't overrun or a way to control the fuel pump volume like the resistors used to drop the pump voltage on a 3/S TT. So if your DSM fuel pump overruns the stock FPR you need a replacement FPR.

Steve

Or in other words the over run happens a different RPM and different loads. You CAN'T tune that out with the AFC. All you end up with are screwed up setting from the one time you tuned out the over run based on that days driving. Your very next driving session where your driving part throttle with 45% instead of 40% in the 4500rpm zone not 4000rpm zone it's now totally different and your AFC settings are totally screwed.

Fuel pressure NEEDS to stay constant varying only with throttle and rpm which the AFC and stock computer are designed to compensate for, not for random overrun of the fpr based on that days driving.

BTW a Commandflo is not an AFPR its only a stupid bolt on thing that can allow you to put more pressure on the diaphram to increase the pressure. You can do the same thing with a pair of vice grips and crushing the shit out of your stock FPR. (which is totally stupid)

 

[gotgrip666]

Are you venting your BOV? That exact same thing happens to some cars when you vent without a blow thru setup.

no im not venting yet , oh and sorry i kep forgeting to put in my links , i ordered this one http://www.dsmtuners.com/parts/product_info.php?cPath=3_144_93&products_id=644

 

[Burnett03]

listen guys, im not putting the afpr down, it is definitely a useful part for tuning, etc. and if u have the money for it then definitely get it, i want one and will get one when i have the cash, im just saying u dont need one and im saying that from personal experiences. my fuel pressure is definitely higher than it should be and i know that, but with a afc u can *bandage* it up, not fix

bandaging is when you cover a wond to heal, and then it heals. putting a safc on a car that has high fuel pressure from overrun is not bandaging it because its not going to get better.. You are just pretending the problem doesnt exist. If you want to run rich and waste gas, be my guess, i on the other hand done, so i run a fpr. It also allows me to bump pressure to get a bit more from my injectors.

 

[Dsm634]

bandaging is when you cover a wond to heal, and then it heals. putting a safc on a car that has high fuel pressure from overrun is not bandaging it because its not going to get better.. You are just pretending the problem doesnt exist. If you want to run rich and waste gas, be my guess, i on the other hand done, so i run a fpr. It also allows me to bump pressure to get a bit more from my injectors.

As long as we're on the subject, any particular fpr you would recommend? I have a 2g w/ 255, afc, and stock injectors, it appears I need one as well.

 

[VBGSX]

As long as we're on the subject, any particular fpr you would recommend? I have a 2g w/ 255, afc, and stock injectors, it appears I need one as well.

I bought mine here:
http://www.fullthrottlespeed.com
I works great.

Another excellent one(from above):
http://www.dsmtuners.com/parts/product_info.php?cPath=3_144_93&products_id=644

Just be sure to get all the necessary accessories(fittings, fuel pressure guage, etc)

One more little fact that may or may not be known.
2g's are notorious for over running the AFPR.
There are 2 main reasons though.
1. The tiny stock AFPR can't keep up
2. On 2g's, people have experienced over run even with an aftermarket AFPR. This really seems to be hit and miss with no ryme or reason. The reason comes down to the Fuel Return hose. On the 2g it's pretty small but like I said, some people have no problem with it. The theory is that there is a possibe kink some where in the line.
Now there is an easy fix for this. Upgrade the return line. Numerous people have have purchased a $5.00 5ft(I believe) section of 3/8th metal brake line and replace the stock return line. The line is soft enough that you can make any bends necessary by hand, if you're careful and take your time. No kinks... I've also read where the problem may just be where the line bends from under the car and runs along the fire wall and stops near the AFPR. Some have had good results just replacing that small section with rubber fuel line.

Just some extra info for the discussion.
Good luck

 

[Burnett03]

As long as we're on the subject, any particular fpr you would recommend? I have a 2g w/ 255, afc, and stock injectors, it appears I need one as well.

do you want a bolt on or one you need to get lines to install? if bolt on get it from www.fullthrottlespeed.com or get a aeromotive afpr but it needs SS lines and fittings. dont forget the gauge, they are useless without one.

 

[gotgrip666]

hmm i just ordered the aeromotive afpr and their fuel rail , now what else do i need to get to set up these? they were saying i needed a fuel line kit or something, i just wanted to know what you guys think i should use and what i have to use. i heard you can use brake lines to use these, somebody give me some help quick please i get my parts Tuesday oh yea should releive the fuel pressure in the system right before doing any of this right?

 

[Burnett03]

hmm i just ordered the aeromotive afpr and their fuel rail , now what else do i need to get to set up these? they were saying i needed a fuel line kit or something, i just wanted to know what you guys think i should use and what i have to use. i heard you can use brake lines to use these, somebody give me some help quick please i get my parts Tuesday oh yea should releive the fuel pressure in the system right before doing any of this right?

here
http://www.slowboyracing.com/more.php?id=1183&

 

[gotgrip666]

here
http://www.slowboyracing.com/more.php?id=1183&

yea i just ordered the return line kit and the inlet feed kit and a guage. ps i cant wait to see how the car runs with the new afpr and high volume fuel rail then my fuel systen will be pretty much complete

 

[steve]

I cant wait to see how the car runs with the new afpr and high volume fuel rail then my fuel systen will be pretty much complete.

Which fuel rail? I'd be interested to see what a "High Volume" rail looks like and how it's accomplished while retaining the stock sized fuel feed and return fittings. I suspect most of these are apperance parts rather than actual performance parts.

Back in the dark ages of DSM tuning (Talon Digest) people used to ream out the stock rail to remove the taper in the center to improve flow. I wonder where the reamer that was passed around went?

Steve

 

[gotgrip666]

Which fuel rail? I'd be interested to see what a "High Volume" rail looks like and how it's accomplished while retaining the stock sized fuel feed and return fittings. I suspect most of these are apperance parts rather than actual performance parts.

Back in the dark ages of DSM tuning (Talon Digest) people used to ream out the stock rail to remove the taper in the center to improve flow. I wonder where the reamer that was passed around went?

Steve

read my posts especially the last one where it says i ordered the inlet and feed lines also the first post where im sure i said the i have the walbro 255 fuel pump and 660 injectorsso no appearance is a plus but its perfoemance im going for, fuel rail http://www.slowboyracing.com/more.php?id=1171&

 

[VBGSX]

........ oh yea should releive the fuel pressure in the system right before doing any of this right?

Yes, do the best you can to relieve it.
Take the gas cap off also. This will help to release the pressure in the tank.
I forgot to do this and fuel sprayed me in the face from the return line.
Once I popped the cap, the tank pressure was released and it stopped spraying.l

Also, it would be a good idea to have a bunch of rags you can stuff around where fuel will come out. That way you're not covering everything in fuel.

 

[Illicit TSi]

This was breifly mentioned in another post.. If you have a 255,you need a FPR and a SAFC,or DSM link.Whichever you chose to go with.Injectors on a 255 should be 720cc max I believe(cant remember that one off hand)or around that.if you havent upgraded your turbo yet or done any internals 800CC injectors are gonna be OVERKILL.Fuel rail isnt really necessary till about 7-800cc injectors and if your gonna run that big of an injector I would go with a standalone FMS.Also For those injectors make sure you have internal work done (cams,pistons AND rods,etc) and fuel management as well as an appropriate turbo and enough boost to support or compliment all these upgrades.Get my drift yet?

Just my .02.I noticed you didnt get the 800's .. Stay with the 660's for a lil bit.Just my opinion.

 

[gotgrip666]

This was breifly mentioned in another post.. If you have a 255,you need a FPR and a SAFC,or DSM link.Whichever you chose to go with.Injectors on a 255 should be 720cc max I believe(cant remember that one off hand)or around that.if you havent upgraded your turbo yet or done any internals 800CC injectors are gonna be OVERKILL.Fuel rail isnt really necessary till about 7-800cc injectors and if your gonna run that big of an injector I would go with a standalone FMS.Also For those injectors make sure you have internal work done (cams,pistons AND rods,etc) and fuel management as well as an appropriate turbo and enough boost to support or compliment all these upgrades.Get my drift yet?

Just my .02.I noticed you didnt get the 800's .. Stay with the 660's for a lil bit.Just my opinion.

i have the agp rs49 50 trim t3/t4 and dsmlink i just need to get a new disc somehow , right now im running about 19 psi

 

[VBGSX]

This was breifly mentioned in another post.. If you have a 255,you need a FPR and a SAFC,or DSM link.Whichever you chose to go with.Injectors on a 255 should be 720cc max I believe(cant remember that one off hand)or around that..

Please be careful about posting what you've heard or think you've read.
You can run much higher than 720cc on a 255 lph pump.
I've run 850's on a 190 rewired pump. Oh and yes I have DSMlink. No problems and I'm not running out of fuel with the 190 rewired pump(per logs). This is on 21-22 PSI, pump gas daily driven. You can see my profile for my upgrades.

if you havent upgraded your turbo yet or done any internals 800CC injectors are gonna be OVERKILL.Fuel rail isnt really necessary till about 7-800cc injectors and if your gonna run that big of an injector I would go with a standalone FMS.Also.

Since he has DSMlink, there is no reason for him not to get as large as he wants. Price differences aren't that much. You will never have to upgrade agian if the performance bug hits. It will run like stock. You know you will have plenty of fuel. Will it be overkill? Maybe. Who cares though. It won't affect his performance and who knows what he'll want to do in the future(larger turbo, 2.3L, 2.4L, etc, etc.)
As far as the fuel rail, there really isn't any need to upgrade it right now. But you saying it's not necessary till 7-800cc injectors is incorrect. There's really no need to upgrade it then. People have run amazing times on the stock lines and stock fuel rail. Will it hurt to do it? Nope, just like going with larger injectors, it's one less thing he will ever have to upgrade.

For those injectors make sure you have internal work done (cams,pistons AND rods,etc) and fuel management as well as an appropriate turbo and enough boost to support or compliment all these upgrades.Get my drift yet?.

Just because you have larger injectors doesn't mean you have to have internal work done.
Fuel is something that you shouldn't skimp on. Do it right once, and you won't have to do it again. Like I said, since he has DSMlink, there's no reason(benifit)(other than saving a couple bucks) to going with just the bare minimum injector. I completely agree that all his parts should compliment each other. Larger injectors will still compliment his mods and have no ill effects if he dials them in properly(deadtime and global) with the link.

I understand you want to help but it's best to talk about stuff that you have first hand knowledge with or link us to the post you're talking about. That way everyone can see exactly what was said on the post you read and the explanation for it.
Good luck

 

[steve]

read my posts especially the last one where it says i ordered the inlet and feed lines also the first post where im sure i said the i have the walbro 255 fuel pump and 660 injectors

I read all your posts before asking. It wasn't clear if you ment the rail was from Aeromotive or from the vender you bought the AFPR from, that's why I asked so I didn't make any assumptions.

If the rail is close to the diameter of the fittings all the way through, I got not problem with them calling it high volume

Thanks for the link.

Steve

 

[Illicit TSi]

Like I said mentioned breifly.... HEres your request.

http://www.dsmtuners.com/forums/showthread.php?t=182110

Going on past references and things I learned first hand I never really needed 700 CC injectors and have always been told they were overkill for what I HAD done at the time.Now I am being told to upgrade my turbo and injectors and a few other things that I held off on and need now that I have a goal to reach.But that was my experience with it.. what is it with guys and chicks modding thier cars? Either we arent running the right parts or what we have is overkill ( yet its the same things you guys use) ..

 

[Bailzz]

Quick Q&A, Installin a PTE 50 port and polished by Garrett and was wondering for managment if I would be fine with this afpr and an safcII? In no rush to push this turbos potential, just got a great deal on it and couldn't pass it up since my exhaust housing went to major crap on the pour 14B. Have RC 550's with 255lb, FMIC w/ 2.5 ICP and manifold w/ tube O2, Apex'i N1. I know everyone's opinion is going to be to get DSMLink but can I do without it?

 

[steve]

With the 50 trim, the 255 l/p, AFPR and SAFC will be fine until you max out those 550s. You can crank up the base fuel pressure to get some more life out of them.

Steve

 

[gotgrip666]

OK guys i got my aeromotive afpr and high volume fuel rail today no can i get a lil tech info on how to install the fuel rail? thanks much