Just wondering how large of a injector I can flow with a single 12MM pump. Have 250's from S&S and have a spare stock LBZ pump or a 10MM also, just wondering how much fuel I need pump side.
Thanks.
Thanks.
Largest Injector On Single 12MM Pump
- Thread starter RobsDmax
- Start date
My 14mm street pump from Exergy drops off rail after 1700us on my redman modded 250% overs in my LLY. I personally am disappointed in my 14mm in terms of what it can flow.
If you're going to aim for using them north of 1k hp I would run that 12mm and 10mm. Less duty cycle and guaranteed higher maintainable pressures.
Kinda what I wondered. I was really hoping to stay conservative at 1k. That would be the most I can see myself making.
I figure my 1750us on these modded 250s should be close to 1050hp-1100hp of fuel (~320mm3). Being a street pump mine only drops AFTER 3500rpm. Up until 3500rpm my pump easily holds that duration.
If you have access to the 12mm AND 10mm I would honestly run those and never worry about needing more pump.
At 1565us/22deg/26ksi on Duramax Tuner's dyno I did 820/1748 with the shitty HSP S400 air filter installed. On the street removing the filter gained me 8-12psi of boost on my 75.
A race 14mm is awesome. Mark at Danville is holding 2200US on his race 14mm with LBZ 250% overs in his white truck. The street pump has a different gerotor section and some other small internal tweaks according to Exergy.
If you already have the 10mm just add a stocker over it and be done. That is tons of fuel. I went with the street pump because I did some horse trading with another member on here.
OK, I am going to look into that, thanks. With my setup I know I can move up and just wanted some opinions on which way would be better for a street truck. Currently sitting at 830 RWHP.
That being said, I know if you can wait on fuel until Thanksgiving LDS/S&S usually have a damn good sale on 10mm pumps, to the point where you can snag one for ~$1450-$1500.
Thxs, I am planning on S&S 150 overs and install will be near the end of this month.
Feel free to fill me in. Truck has a Fass 260HD on it so I do not think supply will be a issue to the pumps.
I realize you're trying to help (you also mentioned GM parts in another post), but don't. Your only warning.
Sorry I have to be the jerk, guys.
Yup, that was pre-PMs.
Noted. I'll look at becoming a vendor for others here, no reason to get scalped at the dealer.
I have seen it many times where injectors was returning to much fuel. Also supply issue, and tuning
a 14mm should be able to supply more than 1750uS IMO.....
We run 250s in our 2.5 truck with danville tuning and with a 12mm we can hold 2200uS just fine. You might want to check inj return rates.
We run 250s in our 2.5 truck with danville tuning and with a 12mm we can hold 2200uS just fine. You might want to check inj return rates.
Street pump or race pump?
Like I said, my pump only falls off after 3500rpm. After talking to Mark @ Danville and Bob @ Duramax tuner they believe that is where they think it could be due to the restrictions above that rpm.
I'll do a return rate test.
Im running 2 stock LBZ pumps with 250s and they hold rail at 22-2400uS, I don't remember what Mark set it at exactly.
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It’s a 12mm pimp. There’s no race or street version. But we turn 42-4300rpm for what it’s worth and hold 29k
I'll dig into.
Going to check the fuel supply pressure and ensure I've got 10-15psi POST FICM going directly into the 8AN feed.
If I don't have a supply issue (either I up the pressure or its fine) and it still drops rail the injectors are coming out for testing.
If the injectors test good I'm going back to the guy I got the pump from used who said it was a good pump and going to see what he wants to do about it.