Big cube FI Injector size?
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Big cube FI Injector size?
I will be honest, I searched and found formulas that made my head spin Could I get some opinions please?
I am seeing 100% duty cycle at 5000 RPM with 60# Mototrons, the car is also leaning out near that area. What size are other people running for injectors? Thanks
I am seeing 100% duty cycle at 5000 RPM with 60# Mototrons, the car is also leaning out near that area. What size are other people running for injectors? Thanks
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I was going to do that with the second fuel pump install, but was told that it was not needed, so I am still running the stock return style plumbing. As you changed the fuel preasure, did you re-tune the IFR to compensate? If I add the FPR to the front, I should be able to just leave the regulator in the tank as the tank regulator is after the front regulator?
Last edited by zapp168; 09-21-2008 at 06:16 PM. Reason: spelling
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Care to calculate for 650 RWHP? I am still trying to get the car running well enough to take it to the dyno. I don't want to go there to hear, "you need this, you need that, come back" The place is not so close. I have posted to ask people with similiar setups and the "guestimate" is 600-650. We just added the second pump and I made my first full 1/4 mile run without it falling on its face. Thank you for the offer.
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Alright, doing a 15% parasitic loss being a manual, I came up with just about 750CHP.
On a 58psi rail that the LSx has, you need a 60lb injector at an 80% duty cycle.
Mototrons are very good injectors, so the problem lying there is fairly small, that is unless someone sold you something other than 60's without telling you.
I would check fuel pressure first and foremost. If its not at 58 throughout the band, they wont give you what you need.
On a 58psi rail that the LSx has, you need a 60lb injector at an 80% duty cycle.
Mototrons are very good injectors, so the problem lying there is fairly small, that is unless someone sold you something other than 60's without telling you.
I would check fuel pressure first and foremost. If its not at 58 throughout the band, they wont give you what you need.
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Alright, doing a 15% parasitic loss being a manual, I came up with just about 750CHP.
On a 58psi rail that the LSx has, you need a 60lb injector at an 80% duty cycle.
Mototrons are very good injectors, so the problem lying there is fairly small, that is unless someone sold you something other than 60's without telling you.
I would check fuel pressure first and foremost. If its not at 58 throughout the band, they wont give you what you need.
On a 58psi rail that the LSx has, you need a 60lb injector at an 80% duty cycle.
Mototrons are very good injectors, so the problem lying there is fairly small, that is unless someone sold you something other than 60's without telling you.
I would check fuel pressure first and foremost. If its not at 58 throughout the band, they wont give you what you need.
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Alright, doing a 15% parasitic loss being a manual, I came up with just about 750CHP.
On a 58psi rail that the LSx has, you need a 60lb injector at an 80% duty cycle.
On a 58psi rail that the LSx has, you need a 60lb injector at an 80% duty cycle.
I just know from personal experienc that with a 3.4 pulley on a D1SC blower setup, a base fuel pressure of 58 will not be enough for 60lbs injectors.
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anyone ever been to www.rceng.com ?? and go to the TECHNICAL SIZING PAGE .... I do have a sticky....
grab you some racetronix 79#ers or something larger
grab you some racetronix 79#ers or something larger
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anyone ever been to www.rceng.com ?? and go to the TECHNICAL SIZING PAGE .... I do have a sticky....
grab you some racetronix 79#ers or something larger
grab you some racetronix 79#ers or something larger
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I was going to do that with the second fuel pump install, but was told that it was not needed, so I am still running the stock return style plumbing. As you changed the fuel preasure, did you re-tune the IFR to compensate? If I add the FPR to the front, I should be able to just leave the regulator in the tank as the tank regulator is after the front regulator?
You should consider a rising-rate regulator setup. It will make tuning the A/F under light load easier and extend your HP support under boost.
Assuming everything is working properly with your current fuel system setup you should be able to support apx. 700 crank HP with a duty cycle of apx. 80%. This does not factor in the parasitic load of the blower or other power accessories.
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Sold...I was honestly looking into that and asked an "expert" and was told it would not be needed. Now as for the in tank regulator, as long as I disconnect the return line from the T- block and plumb the return from the front regulator I don't have to drop my PITA tank again correct? I would rather run a new line than use the EVAP line. BTW thanks everyone for all the help!!!
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Sold...I was honestly looking into that and asked an "expert" and was told it would not be needed. Now as for the in tank regulator, as long as I disconnect the return line from the T- block and plumb the return from the front regulator I don't have to drop my PITA tank again correct? I would rather run a new line than use the EVAP line. BTW thanks everyone for all the help!!!
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These images should help. All this can be done easily with a cutoff tool, file, sandpaper, MAP gas torch, silver solder and some flux. This setup can support 1000HP+ with a proper pump system.
The D/S rail fitting has a -8 Teflon line running to the P/S 'T' fitting. The other side of the 'T' fitting runs to a regulator. Make sure you remove the pulse dampening strips inside the rails once the end caps are cut off. This particular rail setup is from a 950RWHP TT C5 Z06 using a Racetronix / Lonnies DP fuel system.
The D/S rail fitting has a -8 Teflon line running to the P/S 'T' fitting. The other side of the 'T' fitting runs to a regulator. Make sure you remove the pulse dampening strips inside the rails once the end caps are cut off. This particular rail setup is from a 950RWHP TT C5 Z06 using a Racetronix / Lonnies DP fuel system.
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Last edited by Racetronix; 09-25-2008 at 05:48 AM.
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Thank you, that was a lot of information, I am running aftermarket rails, but I get the ides, I am just not looking forward to dropping Mr. fuel tank down, and no....I don't want to cut my car . We got a little busy here so as usual my car moves to the back burner. Thank you very much for all your information.