1G Fuel system recommendations

[dwb]

I'm looking to upgrade the fuel system on my 1g. Currently running a stock system. It seems plenty has changed with injectors specifically so a lot of my research is outdated.

Applicable mods:
ECMLink
Rewired fuel pump
Fresh engine with 8.5:1 compression
Future mods: EVOIII 16G, Exhaust, Wideband

Goals:
~350 HP on 91 pump gas at 5600+ ft. elevation
Daily driver, so needs to idle and run smooth. Willing to sacrifice some performance for drivability if necessary.

I'm looking at the Walbro 255 LPH kit, FueLab 515 FPR kit. Any reason to shy away from either of these?

I'm undecided on injectors. That's why I come here. Do I go high-z or low-z? Is one easier to tune than the other? Does one type work better for a range of environmental factors, like below zero degree starts in the winter and 90+ degree days in the summer? Is there any difference in longevity?
Same goes for sizing. What tunes easy? Any environmental factors?
Initially I'm looking at something like the FIC 950cc low-z. Good, bad, ugly? What would you do in my shoes?

 

[1990TSIAWDTALON]

The difference I found was in LARGE injectors. Over 1200 or 1500cc and Low Z (factory type stuff) does not transition well from low pulse widths to high pulse widths, making them rather finicky in the transition area. The Hi Z injectors that are LARGE are much easier to tune if you are using big injectors. It doesn't sound like you are going with anything to big, so the impedance shouldn't affect the tunability and you should be able to run either type. Thats my .02¢

 

[Justin DuBois]

What he said - and I run a factory FPR with a Supra Green FP which is about 260lph, similar to the WB 255. I'm monitoring FP at the fuel rail side of the fuel filter, and so far, the stocker FPR is working just fine - 720cc Low-z Denso injectors. Big 16G - 24psi, 380hp.

 

[1990TSIAWDTALON]

Nice combination.

 

[dwb]

Thanks for the input guys. All good stuff. It sounds like I've got my pick of injectors. 750 all the way up to 1200.
Anyone have an opinion what's an "ideal" injector size for an EVOIII 16g? Is there a downside if I were to go too big, like 1100-1200cc?

 

[Justin DuBois]

I’m at the limit with 720’s with max boost with a Big 16G running normal fuel pressures with E25 (94oct) mixed fuel. I’d run even more ethanol if I had more injector.

 

[JohntyBee]

Thanks for the input guys. All good stuff. It sounds like I've got my pick of injectors. 750 all the way up to 1200.
Anyone have an opinion what's an "ideal" injector size for an EVOIII 16g? Is there a downside if I were to go too big, like 1100-1200cc?

I was running on FIC Hi-Z 1000s with no issues before I swapped over to a HX35 on the same injectors. I’ve been messing around with E85 with them but I’ll probably be going a few steps higher in CCs in the future

 

[diambo4life]

Will you be running ethanol?

 

[dwb]

Will you be running ethanol?

Not in the plans. This is just a daily driver (as much as a DSM can be at least).

 

[SouthIndy_Talon]

What he said - and I run a factory FPR with a Supra Green FP which is about 260lph, similar to the WB 255. I'm monitoring FP at the fuel rail side of the fuel filter, and so far, the stocker FPR is working just fine - 720cc Low-z Denso injectors. Big 16G - 24psi, 380hp.

Is that like a OEM supra pump?

 

[Justin DuBois]

Is that like a OEM supra pump?

yes!

 

[SouthIndy_Talon]

yes!

Care to share specific like a part number or where you found one? I would like to run something similar

 

[Justin DuBois]

Care to share specific like a part number or where you found one? I would like to run something similar

, well - 20 years ago, I walk into Road Race engineering, tell them I have a Big16G and I want to upgrade the stock fuel pump - They they pull a Supra Green pump off the shelf, and hand it too me in a brown box.

I'd need to look around to figure out what Toyota part number that would be - Probably this:

Fuel Pump - Toyota (23221-46110)​

 

[jdxnc]

Get yourself a set of 1000cc high Z injectors, there's no reason to bother with low Z these days. idle and tuning is much better and will have headroom for E85 if you ever decide to.

 

[1990TSIAWDTALON]

I would only suggest an E85 compatible pump to compliment your setup, and follow Jason's advice, although that would probably require a AFPR.
Hi Z injectors now days are the goto thing. All 3 of my DSMs have Hi Z injectors.

 

[dwb]

This is the exact stuff I was looking for! Thanks everyone!

I guess high-z is the go-to choice today. Pretty easy to make my own resister-delete pigtail and it looks like at least the FIC high-z injectors can be ordered with DSM plug adapters. Easy stuff. Still need to decide on what CC I want, definitely 1000 or less.

With consideration of e85 (which isn't in my plans BTW), it doesn't look like I can use the Walbro 255. Would have to go all the way to the 450 in the Wb flavor, which seems like overkill for 350hp goal. I'm sure the 255 is loud but the 450? What about the lines, do those need to be changed out for e85?

 

[Justin DuBois]

This is the exact stuff I was looking for! Thanks everyone!

I guess high-z is the go-to choice today. Pretty easy to make my own resister-delete pigtail and it looks like at least the FIC high-z injectors can be ordered with DSM plug adapters. Easy stuff. Still need to decide on what CC I want, definitely 1000 or less.

With consideration of e85 (which isn't in my plans BTW), it doesn't look like I can use the Walbro 255. Would have to go all the way to the 450 in the Wb flavor, which seems like overkill for 350hp goal. I'm sure the 255 is loud but the 450? What about the lines, do those need to be changed out for e85?

I'm curious what people are saying is "E85" compatable.

Maybe I'm just getting away with it running E25, but the Supra Green and 720cc Denso injectors are so far working well with mixed fuel.

 

[We're on Boost]

With consideration of e85 (which isn't in my plans BTW), it doesn't look like I can use the Walbro 255. Would have to go all the way to the 450 in the Wb flavor, which seems like overkill for 350hp goal. I'm sure the 255 is loud but the 450?

The 255 is so reliable, so cheap, and so easy to install, I would start out with it. Then if you do switch to E85 or some % of E, then switch pumps, and then you can deal with all the little stuff you have to do to make a large body Walbro fit in there on your hanger, I mean they don't even have the same size (diameter) outlet pipes. The 255 will go in pretty much just like a stock pump. Note the grommet you can get to make the seal part of it better and easier than fiddling with the stupid o-ring and spacer used by the stock setup.

 

[dwb]

The 255 is so reliable, so cheap, and so easy to install, I would start out with it. Then if you do switch to E85 or some % of E, then switch pumps, and then you can deal with all the little stuff you have to do to make a large body Walbro fit in there on your hanger, I mean they don't even have the same size (diameter) outlet pipes. The 255 will go in pretty much just like a stock pump. Note the grommet you can get to make the seal part of it better and easier than fiddling with the stupid o-ring and spacer used by the stock setup.

Oh geeze, I didn't even consider fitment issues with a big pump. Agreed, 255 is pretty cheap and seemingly easy so that's my first choice. I'll have to look into the seal and if that comes with the kit. Thanks for pointing that out.

 

[We're on Boost]

The Walbro install kit for the 255 comes with everything you need except this grommet. The install kit expects you to reuse the original plastic spacer under the o-ring, and a cap on top of that. With the grommet, you don’t use the o-ring, the spacer, or the cap. You just use the grommet. It fits very tight into the bellmouth receiver so use some kind of rubber grease or oil on the outside of it.

Here in post #43 is a link to the STM page where you can buy these grommets, and up in post #40 is a link to a MAP page for the same grommet. In post #41 is a pic of my current 255 with an unobtainium Viton piece on the outlet (which I made from some soft tubing that you can't buy anymore).

https://www.dsmtuners.com/threads/fuel-pump.542840/page-2#post-153877113

BTW I have a Walbro 255 in the tank with 30 to 60% ethanol (flex fuel). Used the same pump from 2016 to 2022 and only replaced it because I was in the tank anyway for a look and a new sock. So apparently even though this pump is not recommended for E85, I would have to say it is ok with flex fuel if you aren’t going to go over 60% ethanol.

 

[1990TSIAWDTALON]

My experience with the 255 and E85 was that I used is as a lift pump to pump E out of my 55 gallon drum. It lasted about a year and then froze up solid. With mixed fuels, I am sure it gets lubed on the veins but not with straight Ethanol, which takes any oil out of anything. I used some old E to clean some parts and it works amazing but if you fail to get all of the "gunk" off of whatever you are cleaning, you are left with a very dry and powdery substance that has to have a wire brush to remove. That is E taking ALL of the oil out but leaving behind anything that wasn't clean before it dried up.
The guys are right. Use the 255 as it is a drop in pump. If you get the itch for E, you can upgrade at that time. As for the sound, my 525 is very quiet and I have one in all 3 DSM's and one in the 86 Z28 that is Holley fuel injected. Nice pumps!

 

[dwb]

I ordered up some 1000cc high-z injectors, WB 255, and a Fuelab FPR. We'll see how it works out!

 

[Spleen8urLSX]

What you got ordered will be plenty for what you want to do. Shoot on pump gas 650-680cc injectors would even suffice for 350whp, but the high impedance 1000s will be nice as others have mentioned. Even while way overkill some high impedance 1250s or 1650’s will still be able to maintain good idle and what not. Anything bigger can be hit or miss on pump gas but worse thing that happens is you end up dialing your idle in a bit richer than stock but not rich enough to hurt anything or even really notice, however I’ve known some able to dial in 2200s at idle just like stock on pump gas if not just a touch rich, but also not really a problem with e85.

As far as your 350 goal that’s where the long shot will be with 91 octane with the 16g. Perhaps doable on an EXTREMELY generous dyno but would never see that on a Mustang dyno (call them a heartbreaker dyno for a reason). On my first 16g I was able to squeak out 284 on a Mustang dyno at the front wheels spiking 22ish psi with a primitive set up, evo 3 16g, 560cc injectors, hacked 1g maf, garbage Aeromotive 340 pump that ended up in a trash can 2 years later, safc 2 for “tuning”, and that was 93 octane pump gas with a gallon of 110 octane race gas mixed in with every 4 gallons of 93 octane. Wouldn’t have used the race gas at all but was running 9:1 compression non turbo pistons and the stock 1g timing map was too aggressive for that much compression and it’d start seeing knock, with the 110 mixed in knock wasn’t an issue (no way to control timing).

With this being said don’t hesitate to make the jump to e85 if you have it available near you, keep in mind ecmlink has flex fuel capability’s to self adjust between pump gas and e85 so you can easily switch between whatever is available at the time. Gotta remember e85 isn’t anything special, it’s original intention was for Karen’s to pump it into their factory flex fuel Explorer on the way to the grocery store, just turns out it makes good poor people race gas, nothing you can’t pump into a daily driver if you desired and many do. When I made the switch the following year to e85, ecmlink, 1450cc injectors (which I HATED, those injectors definitely back the comments about large low impedance injectors) and 272 cams I was able to make 420whp and and 430wtq on a dynapak that’s not the heart breaker the Mustang dynos are but isn’t nearly as generous as many of the dynojets in the area. Don’t blame you if e85 isn’t for you, I’ll never knock anyone there, but if you’re dead set on 350 you might want to reconsider the 16g as you’ll be hard pressed to see even 300 at the wheels on a realistic dyno on straight 91 octane.

 

[Justin DuBois]

What you got ordered will be plenty for what you want to do. Shoot on pump gas 650-680cc injectors would even suffice for 350whp, but the high impedance 1000s will be nice as others have mentioned. Even while way overkill some high impedance 1250s or 1650’s will still be able to maintain good idle and what not. Anything bigger can be hit or miss on pump gas but worse thing that happens is you end up dialing your idle in a bit richer than stock but not rich enough to hurt anything or even really notice, however I’ve known some able to dial in 2200s at idle just like stock on pump gas if not just a touch rich, but also not really a problem with e85.

As far as your 350 goal that’s where the long shot will be with 91 octane with the 16g. Perhaps doable on an EXTREMELY generous dyno but would never see that on a Mustang dyno (call them a heartbreaker dyno for a reason). On my first 16g I was able to squeak out 284 on a Mustang dyno at the front wheels spiking 22ish psi with a primitive set up, evo 3 16g, 560cc injectors, hacked 1g maf, garbage Aeromotive 340 pump that ended up in a trash can 2 years later, safc 2 for “tuning”, and that was 93 octane pump gas with a gallon of 110 octane race gas mixed in with every 4 gallons of 93 octane. Wouldn’t have used the race gas at all but was running 9:1 compression non turbo pistons and the stock 1g timing map was too aggressive for that much compression and it’d start seeing knock, with the 110 mixed in knock wasn’t an issue (no way to control timing).

With this being said don’t hesitate to make the jump to e85 if you have it available near you, keep in mind ecmlink has flex fuel capability’s to self adjust between pump gas and e85 so you can easily switch between whatever is available at the time. Gotta remember e85 isn’t anything special, it’s original intention was for Karen’s to pump it into their factory flex fuel Explorer on the way to the grocery store, just turns out it makes good poor people race gas, nothing you can’t pump into a daily driver if you desired and many do. When I made the switch the following year to e85, ecmlink, 1450cc injectors (which I HATED, those injectors definitely back the comments about large low impedance injectors) and 272 cams I was able to make 420whp and and 430wtq on a dynapak that’s not the heart breaker the Mustang dynos are but isn’t nearly as generous as many of the dynojets in the area. Don’t blame you if e85 isn’t for you, I’ll never knock anyone there, but if you’re dead set on 350 you might want to reconsider the 16g as you’ll be hard pressed to see even 300 at the wheels on a realistic dyno on straight 91 octane.

91 oct, with a Big 16G was knock limited for me. I either had to pull timing or boost to run without knock. My solution was to mix in e85 until the knock went away. -e25 (94oct) was good enough for 380 whp calculated from ECMlink logs (with an accurate vehicle weight) 24-22psi

 

[dwb]

Not dead set on any HP, just something that puts a smile on my face and gives an Audi/BMW a run for their money
I figure in the Denver metro area I'd easily find e85 or even 93 octane, but I never see it. Granted I usually fuel up at the same places. Pretty sure I could find some out near Bandimere (soon to RIP).