346+F1+17lbs= 770rwhp
11-24-2005, 02:24 PM
#22
Originally Posted by LTLHOMER
Cool numbers...that through a stick or auto?
I think you are out of fuel volume on that 255 pump. 255 liter/hour equals 67 gallons/hour which is also equal to about 404-lbs/hr of fuel flow. If you do your math, 75# injectors times 8 running at 90% DC equals 540-lbs/hr of fuel, 90 gallons/hour, or 342 liters/hour. So somehow, that pump is putting out almost 35% more that its design. Sounds to good to be true.
11-24-2005, 04:32 PM
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Based on what I've seen and what others have reported, not all fuel pumps are created equal. Small differences in tolerances can make substantial differences in performance within the same model line. I believe Bosch has taken one of their pump lines and picked the best of the best and given these 'select' pumps a separate part number (which are not widely available) and rated them for use above the levels of the std. part number (if that makes sense???).
Either way, the results Don is seeing are VERY impressive IMO... that pump must have been kissed by God himself!
Either way, the results Don is seeing are VERY impressive IMO... that pump must have been kissed by God himself!
11-24-2005, 05:27 PM
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Originally Posted by Gold Phoenix
Not to sound like a jerk, but read his original post. It said M6.
I think you are out of fuel volume on that 255 pump. 255 liter/hour equals 67 gallons/hour which is also equal to about 404-lbs/hr of fuel flow. If you do your math, 75# injectors times 8 running at 90% DC equals 540-lbs/hr of fuel, 90 gallons/hour, or 342 liters/hour. So somehow, that pump is putting out almost 35% more that its design. Sounds to good to be true.
I think you are out of fuel volume on that 255 pump. 255 liter/hour equals 67 gallons/hour which is also equal to about 404-lbs/hr of fuel flow. If you do your math, 75# injectors times 8 running at 90% DC equals 540-lbs/hr of fuel, 90 gallons/hour, or 342 liters/hour. So somehow, that pump is putting out almost 35% more that its design. Sounds to good to be true.
ya ok, this is all made up. some of you people Last edited by smokinHawk; 11-28-2005 at 09:43 AM. Reason: used the Lords name in vein
11-24-2005, 06:40 PM
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Originally Posted by Gold Phoenix
Not to sound like a jerk, but read his original post. It said M6.
I think you are out of fuel volume on that 255 pump. 255 liter/hour equals 67 gallons/hour which is also equal to about 404-lbs/hr of fuel flow. If you do your math, 75# injectors times 8 running at 90% DC equals 540-lbs/hr of fuel, 90 gallons/hour, or 342 liters/hour. So somehow, that pump is putting out almost 35% more that its design. Sounds to good to be true.
I think you are out of fuel volume on that 255 pump. 255 liter/hour equals 67 gallons/hour which is also equal to about 404-lbs/hr of fuel flow. If you do your math, 75# injectors times 8 running at 90% DC equals 540-lbs/hr of fuel, 90 gallons/hour, or 342 liters/hour. So somehow, that pump is putting out almost 35% more that its design. Sounds to good to be true.
And I don't think anyone is saying the dyno didn't say 770rwhp, he is probably saying the dyno might be reading a tad high based on the limitations of the pump. I would tend to agree but take it to the track and get the numbers that matter.
G'luck.
11-24-2005, 07:03 PM
#26
Originally Posted by LTLHOMER
No problem man I missed it...
And I don't think anyone is saying the dyno didn't say 770rwhp, he is probably saying the dyno might be reading a tad high based on the limitations of the pump. I would tend to agree but take it to the track and get the numbers that matter.
G'luck.
And I don't think anyone is saying the dyno didn't say 770rwhp, he is probably saying the dyno might be reading a tad high based on the limitations of the pump. I would tend to agree but take it to the track and get the numbers that matter.
G'luck.
As for the fuel,this isn't the first 255 pump we've pushed this far and probly won't be the last. Have you heard of voltage booster's? This car has one,17volt's at WOT
11-24-2005, 07:51 PM
#27
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Originally Posted by Slowhawk
Could be but I'm not the dyno queen type of guy.The rumer is my dyno is one of the lowest reading dyno's around.
As for the fuel,this isn't the first 255 pump we've pushed this far and probly won't be the last. Have you heard of voltage booster's? This car has one,17volt's at WOT
As for the fuel,this isn't the first 255 pump we've pushed this far and probly won't be the last. Have you heard of voltage booster's? This car has one,17volt's at WOT
But good luck!
11-24-2005, 09:09 PM
#28
Originally Posted by LTLHOMER
Hate to see the result of the pump going out which seems like a probable outcome when pushing it so far past its limits. I'll stick with my 2025 and not worry about it. I'm not a dynoqueen guy either...I know what mine made and I wouldn't even consider using a single 255 lph pump. lol
But good luck!
But good luck!
If it blows we will make it faster 
11-25-2005, 01:15 AM
#29
Originally Posted by Slowhawk
Could be but I'm not the dyno queen type of guy.The rumer is my dyno is one of the lowest reading dyno's around.
As for the fuel,this isn't the first 255 pump we've pushed this far and probly won't be the last. Have you heard of voltage booster's? This car has one,17volt's at WOT
As for the fuel,this isn't the first 255 pump we've pushed this far and probly won't be the last. Have you heard of voltage booster's? This car has one,17volt's at WOT
Something you also have to consider is that on a dyno there is no g-forces acting on the car. When you are at the track trying to launch, the fuel pump has to not only push the fuel forward to feed the injectors, but also push against the accelerating g-forces of the car. If you ever notice on a Top Fuel or Pro Stock car, the fuel cell is in the front to the g-forces can help deliver fuel the pump and engine.
I am sure that the 255 pump can support more power on a dyno, but not at the track. Myself, I would be afraid to use your setup at the track. The last thing you want is it to go into a lean condition and backfire through the intake, blow a head gasket, or melt a piston. Now, if you can get two 255 in the tank running parallel, you would be safer.
Oh, and about my math who ever that was, go back to school. He gave me all the numbers, I ran and explained them to you guys, and I noticed something wasn't right. I am attaching a pic that shows a TYPICAL 255-L/hr in-tank fuel pump. If you take the numbers I showed at the top you will see that one pump may not do the job. But divide the number in half and you can use two safely. Also, look at the operating pressure that he is running. Since he is not boost reference you have to take that pressure minus the boost pressure (17psi) and that is the actual flow the pump is moving. It is not the pressure of fuel, it is the volume that is needed to keep the motor running. That is why speed shops out there sell complete fuel kits that 700HP with one pump and +900HP with two.
I am not bashing his numbers, I am concerned about his fuel system.
11-25-2005, 05:34 AM
#30
I agree with what your saying but the Vette system give's little room.This car has already been street tested to 6800rpm in 4th on the street with a wideband and it does hold A/F.For a safety measure we will be running methenol at the track which will make up the extra fuel needed at the track/high rpm area.If this was an A4 there would be no way this could push over 600hp without running out of fuel.
As for racing.I give up on C5's,there drivelines just plain suck and can't take the abuse.We shattered the built rear in this thing within 6' of launch last time
As for racing.I give up on C5's,there drivelines just plain suck and can't take the abuse.We shattered the built rear in this thing within 6' of launch last time
11-26-2005, 11:03 AM
#32
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for all the math racers in here, my setup had a single intank pump and went over 700 rwhp as well, drove it like this for a year an beat the **** out of it. Fuel systems are not just pumps, but im sure you all know that.
11-27-2005, 02:07 AM
#35
Originally Posted by PurEvl
for all the math racers in here, my setup had a single intank pump and went over 700 rwhp as well, drove it like this for a year an beat the **** out of it. Fuel systems are not just pumps, but im sure you all know that.
Think about an air compresor doing certain jobs. You have little 3-gallon one to fill air into tires or maybe some air brush painting. Then you have the 60-gallon tank with a larger two-cylinder compressor. And finally the industrial compressor with a larger storage tank and screw-type compress for faster buildup of pressure. Now, if you need to use just impact gun, paint a whole car or something that only uses one air line at a time, then the 60-gal would work fine. If you try to use that same compressor on let's say a six bay shop where every bay is using air, then the 60-gal maybe too small because it would be running all day working hard and fail before you realize it. The industrial is better suited for that kind of work. And yes there might be some days where you don't need the big compressor because two guys are sick and one is on vacation, but it is nice to have it available when you need it.
I rather have large enough pump(s) with matching sized lines to feed a highpower motor than it leaning out on me one day while at WOT.
11-27-2005, 05:17 AM
#36
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I think he is fully aware of the pumps abilities, or lack of abilities. That isnt what the initial post was about I'm sure.
And the duration of time the pump is actually required to work at full capacity, or indeed over it would be short enough it shouldnt be a major concern, although in an ideal world everyone knows an upgrade would be better..
But interesting to see how good those little pumps are !!
And the duration of time the pump is actually required to work at full capacity, or indeed over it would be short enough it shouldnt be a major concern, although in an ideal world everyone knows an upgrade would be better..
But interesting to see how good those little pumps are !!
11-28-2005, 08:46 PM
#40
Originally Posted by Pro Stock John
Nice dyno numbers!
What will the car trap, if you hit the 1320?
As far as the fuel setup goes, that's another topic for another thread.
What will the car trap, if you hit the 1320?
As far as the fuel setup goes, that's another topic for another thread.
The plan for an A3 is in the works. 