Out of fuel, Suggestions
Out of fuel, Suggestions 408 with billet 80 on about 13psi, going by trap speed I'm right at 800 to the tire with 95% duty cycle. I'm looking to make another 100 whp before I change the fuelsystem next season which will probably be a 2 or 3 Walbro 450's in my fuel cell.
Holley 12-1800
-12 feed
-10 return
FID 1300's at 50 base 1:1 Regulator
I'm sure bumping fuel pressure up to 60psi and run total of 75-77psi would probably squeeze a little more fuel out of my combo I don't think it's 100whp worth so I came up with a few options.
1. Y off the fuel system and add a Bosch 044 inline. Probably the more expensive option and more work.
2. Add a methanol kit, pretty much a bandaid but relatively cheap if I run a cooking mist kit
3. The most appealing to me, add a Kenne Bell Boost A Pump which activates at 3psi. I'm just not sure if the BAP William supply the extra bolts to both pumps or just one?
Holley 12-1800
-12 feed
-10 return
FID 1300's at 50 base 1:1 Regulator
I'm sure bumping fuel pressure up to 60psi and run total of 75-77psi would probably squeeze a little more fuel out of my combo I don't think it's 100whp worth so I came up with a few options.
1. Y off the fuel system and add a Bosch 044 inline. Probably the more expensive option and more work.
2. Add a methanol kit, pretty much a bandaid but relatively cheap if I run a cooking mist kit
3. The most appealing to me, add a Kenne Bell Boost A Pump which activates at 3psi. I'm just not sure if the BAP William supply the extra bolts to both pumps or just one?
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Joined: Mar 2014
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From: Ohio
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How far are guys going with fuel pressure on the Holley 12-1800's. Figure I could go up to 60 base and 15-17psi should be just under 80psi
Stock ecu so I don't log FP but I remember glancing at it and it seemed ok. I'll need to take a recording of it and see if it's rising 1:1
Stock ecu so I don't log FP but I remember glancing at it and it seemed ok. I'll need to take a recording of it and see if it's rising 1:1
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Verdad Gallardo Restricted User
Joined: Mar 2014
Posts: 7,192
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From: Ohio
Pump/injectors is usually a balancing game when it comes to pressure.
Less pressure = more pump flow, less injector flow.
More pressure = less pump flow, more injector flow.
Increase the pressure about 5 PSI at a time. Duty cycle should go down as the injectors start to flow more, and then back up as the pump starts being restricted. As far as tuning goes, its just a simple change.
Less pressure = more pump flow, less injector flow.
More pressure = less pump flow, more injector flow.
Increase the pressure about 5 PSI at a time. Duty cycle should go down as the injectors start to flow more, and then back up as the pump starts being restricted. As far as tuning goes, its just a simple change.
210lb injectors are cheapish if you want to keep that pump. Run it at 30-35 base and it should go pretty far.
Since thats not a constant duty cycle rated pump, running an aem380/044/GSL392 in parallel sounds like the best option to me. Turn the Holley on in boost only. Cruise around on the other pump.
Since thats not a constant duty cycle rated pump, running an aem380/044/GSL392 in parallel sounds like the best option to me. Turn the Holley on in boost only. Cruise around on the other pump.
210lb injectors are cheapish if you want to keep that pump. Run it at 30-35 base and it should go pretty far.
Since thats not a constant duty cycle rated pump, running an aem380/044/GSL392 in parallel sounds like the best option to me. Turn the Holley on in boost only. Cruise around on the other pump.
Since thats not a constant duty cycle rated pump, running an aem380/044/GSL392 in parallel sounds like the best option to me. Turn the Holley on in boost only. Cruise around on the other pump.
I really like the idle quality of the injectors I have right now so I think I might try the 3rd pump.
If I were to take the 3rd pump in series approach, what would be the best position to route it in my fuel system? Who need additional filter or filters if I put it after my 12-1800 that already has pre and post?
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
You're wasting your time doing anything without checking fuel pressure under load. And what fuel are you using ?
Holley rate that pump at 1800hp ? Even if that was massively optimistic, 800hp pump fuel shouldnt even have that pump anywhere near struggling, and 1300cc injectors likewise.
And even on ethanol....pump should be ok ?
And if you do a BAP, it will provide extra power to whichever pumps YOU wire it up to....if it is both, make sure the unit is designed to handle the current of both those pumps.
And if those Holley things are just a pair of Walbro 255's inside....why not just throw in a couple of 320/340 type Walbros instead ? Are they not same fitment ?
Holley rate that pump at 1800hp ? Even if that was massively optimistic, 800hp pump fuel shouldnt even have that pump anywhere near struggling, and 1300cc injectors likewise.
And even on ethanol....pump should be ok ?
And if you do a BAP, it will provide extra power to whichever pumps YOU wire it up to....if it is both, make sure the unit is designed to handle the current of both those pumps.
And if those Holley things are just a pair of Walbro 255's inside....why not just throw in a couple of 320/340 type Walbros instead ? Are they not same fitment ?
You're wasting your time doing anything without checking fuel pressure under load. And what fuel are you using ?
Holley rate that pump at 1800hp ? Even if that was massively optimistic, 800hp pump fuel shouldnt even have that pump anywhere near struggling, and 1300cc injectors likewise.
And even on ethanol....pump should be ok ?
And if you do a BAP, it will provide extra power to whichever pumps YOU wire it up to....if it is both, make sure the unit is designed to handle the current of both those pumps.
And if those Holley things are just a pair of Walbro 255's inside....why not just throw in a couple of 320/340 type Walbros instead ? Are they not same fitment ?
Holley rate that pump at 1800hp ? Even if that was massively optimistic, 800hp pump fuel shouldnt even have that pump anywhere near struggling, and 1300cc injectors likewise.
And even on ethanol....pump should be ok ?
And if you do a BAP, it will provide extra power to whichever pumps YOU wire it up to....if it is both, make sure the unit is designed to handle the current of both those pumps.
And if those Holley things are just a pair of Walbro 255's inside....why not just throw in a couple of 320/340 type Walbros instead ? Are they not same fitment ?
The BAP I was interested is for dual pumps but at the price point it would just make sense to add another pump or different pump all together.
You know I never really thought of swapping the pumps inside the Holley, I'm gonna log FP, crank up the base pressure 5-10psi and see where that gets me. If I can swap the pumps inside the Holley that would be easy peazy
As mentioned before, if those are the FIC 127s, they are rated at 4-bar, so about 120 at 50psi base. With that said, 95% DC should get you about 960rwhp. I believe the inj DC is that high because of the FP is dropping as stevieturbo said. Pumps cannot keep up.
https://rspimages.holley.com/12-1600.jpg
Holley's flow chart rates the 1800 pump at about 140gph @ 63psi (your 50 base + 13 boost) at 13.8V. That's about 840lbs and assuming .8 BSFC for E85 (more if you run it fat), that's about 1050 at the crank. However, that assumes the pump is seeing 13.8V and you have to factor in flow loss for the hose, filters and fittings, especially with bends. Everyone forgets about that. I am guessing the pumps are nowhere close to supporting the rated 1050 and therefore less than 800rwhp.
You can obviously get another 100hp out of the injs by jacking up the base FP but that makes the pumps put out less. I think you have to replace the pumps or add the BAP. If you go the BAP route, I would suggest using the ECM to stage the 2nd pump and run the BAP on the 2nd pump only. My feedback is from my personal experience with the same issue trying to make more hp than your goal and I went the BAP route with a 044 and a AEM340 with the BAP on the AEM coming on at 7psi.
You could run it again to log FP but why risk it. You could also turn down the base FP, redo the REQ FUEL and see if the inj DC comes down because the pumps are capable of flowing a little more. However, the numbers don't lie.
https://rspimages.holley.com/12-1600.jpg
Holley's flow chart rates the 1800 pump at about 140gph @ 63psi (your 50 base + 13 boost) at 13.8V. That's about 840lbs and assuming .8 BSFC for E85 (more if you run it fat), that's about 1050 at the crank. However, that assumes the pump is seeing 13.8V and you have to factor in flow loss for the hose, filters and fittings, especially with bends. Everyone forgets about that. I am guessing the pumps are nowhere close to supporting the rated 1050 and therefore less than 800rwhp.
You can obviously get another 100hp out of the injs by jacking up the base FP but that makes the pumps put out less. I think you have to replace the pumps or add the BAP. If you go the BAP route, I would suggest using the ECM to stage the 2nd pump and run the BAP on the 2nd pump only. My feedback is from my personal experience with the same issue trying to make more hp than your goal and I went the BAP route with a 044 and a AEM340 with the BAP on the AEM coming on at 7psi.
You could run it again to log FP but why risk it. You could also turn down the base FP, redo the REQ FUEL and see if the inj DC comes down because the pumps are capable of flowing a little more. However, the numbers don't lie.
As mentioned before, if those are the FIC 127s, they are rated at 4-bar, so about 120 at 50psi base. With that said, 95% DC should get you about 960rwhp. I believe the inj DC is that high because of the FP is dropping as stevieturbo said. Pumps cannot keep up.
https://rspimages.holley.com/12-1600.jpg
Holley's flow chart rates the 1800 pump at about 140gph @ 63psi (your 50 base + 13 boost) at 13.8V. That's about 840lbs and assuming .8 BSFC for E85 (more if you run it fat), that's about 1050 at the crank. However, that assumes the pump is seeing 13.8V and you have to factor in flow loss for the hose, filters and fittings, especially with bends. Everyone forgets about that. I am guessing the pumps are nowhere close to supporting the rated 1050 and therefore less than 800rwhp.
You can obviously get another 100hp out of the injs by jacking up the base FP but that makes the pumps put out less. I think you have to replace the pumps or add the BAP. If you go the BAP route, I would suggest using the ECM to stage the 2nd pump and run the BAP on the 2nd pump only. My feedback is from my personal experience with the same issue trying to make more hp than your goal and I went the BAP route with a 044 and a AEM340 with the BAP on the AEM coming on at 7psi.
You could run it again to log FP but why risk it. You could also turn down the base FP, redo the REQ FUEL and see if the inj DC comes down because the pumps are capable of flowing a little more. However, the numbers don't lie.
https://rspimages.holley.com/12-1600.jpg
Holley's flow chart rates the 1800 pump at about 140gph @ 63psi (your 50 base + 13 boost) at 13.8V. That's about 840lbs and assuming .8 BSFC for E85 (more if you run it fat), that's about 1050 at the crank. However, that assumes the pump is seeing 13.8V and you have to factor in flow loss for the hose, filters and fittings, especially with bends. Everyone forgets about that. I am guessing the pumps are nowhere close to supporting the rated 1050 and therefore less than 800rwhp.
You can obviously get another 100hp out of the injs by jacking up the base FP but that makes the pumps put out less. I think you have to replace the pumps or add the BAP. If you go the BAP route, I would suggest using the ECM to stage the 2nd pump and run the BAP on the 2nd pump only. My feedback is from my personal experience with the same issue trying to make more hp than your goal and I went the BAP route with a 044 and a AEM340 with the BAP on the AEM coming on at 7psi.
You could run it again to log FP but why risk it. You could also turn down the base FP, redo the REQ FUEL and see if the inj DC comes down because the pumps are capable of flowing a little more. However, the numbers don't lie.
Yea I think adding base pressure should give me a little more power but even that isn't enough.
I would really be interested in swapping the pumps inside the Holley for AEM 340's, wonder if anyone has done that. They are exactly the same dimensions. That would be super easy to do and won't require any extra fittings or expensive Y blocks.
I believe the inj DC is that high because of the FP is dropping as stevieturbo said. Pumps cannot keep up.
I think you have to replace the pumps or add the BAP. If you go the BAP route, I would suggest using the ECM to stage the 2nd pump and run the BAP on the 2nd pump only. My feedback is from my personal experience with the same issue trying to make more hp than your goal and I went the BAP route with a 044 and a AEM340 with the BAP on the AEM coming on at 7psi.
I think you have to replace the pumps or add the BAP. If you go the BAP route, I would suggest using the ECM to stage the 2nd pump and run the BAP on the 2nd pump only. My feedback is from my personal experience with the same issue trying to make more hp than your goal and I went the BAP route with a 044 and a AEM340 with the BAP on the AEM coming on at 7psi.
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
it is absolutely essential to know what fuel pressure is doing, under load, when it matters in this instance.
I had the same issue. I added a KB BAP,(21V version) to my 4303 on E85 and it works amazing. My voltage was only 13.1 going down the track before. I was only at 722rwhp before with 43 base running 13 pounds of boost and it was higher on the duty cycle with 160lb Holley injectors than I was comfortable with to turn it up any more. Fuel pressure is now 1:1 through the rpm range turned up to 17psi of boost and duty cycle went WAY down! (I don't remember the exact figures off the top of my head) Now I am going to wick it up to 20-22psi and going to see tonight how it looks on a full pass.
I also read somewhere that you set the BAP up on a boost switch the car will not respond well to receiving 21V so quickly under boost... have you experienced this?
I was really studying my last few logs from the track and I think I figured out why IDC was a lot higher then I think it should be.
First trip to the track I was on 13psj and went 135 on 7* of timing, 137 with 9* and then 140 on 11* timing. All of those passes the highest IDC I saw was 88%. On the last pass I threw the belt right after 3rd gear and what didn't occur to me is that my voltage dropped down to the low 12's. Reviewed the last log and saw that it was a little lean up top (.83-.85) I figured it was just from all the additional timing. So I added probably 5-8% of fuel up top and packed up from the track.
Fast forward to my next test session i ended up trapping right at 2 more mph in the 1/8 with 2 more degrees of timing then my last outing but IDC was 95% now. Logs show me in the .73-.75 range most of the pass so that's about half a point richer.
With that said I still have atleast another 100 wheel I want to make so I'll check FP, possibly bump it up and try again when the weather clears up. I'm in Houston so hurricane Harvey is headed straight to us.