Has anyone got dyno proof of the gains going to a full 3" exhaust?
06-16-2005, 08:02 PM
#121
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You can install a 3" on the car, and if you don't add fuel, it may
in fact hurt the performance. It's lean because of the increased
efficiency. I usually add about 4-5psi on a fairly stock car.
4" would require more. It makes more power.
Wes
in fact hurt the performance. It's lean because of the increased
efficiency. I usually add about 4-5psi on a fairly stock car.
4" would require more. It makes more power.
Wes
06-16-2005, 10:15 PM
#123
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Posted: by stewardx
You can install a 3" on the car, and if you don't add fuel, it may
in fact hurt the performance. It's lean because of the increased
efficiency. I usually add about 4-5psi on a fairly stock car.
4" would require more. It makes more power.
A afm or maf can measure the additional air flow and add the fuel through a load calculation. If you raise the fp you most likely will run rich.
You can install a 3" on the car, and if you don't add fuel, it may
in fact hurt the performance. It's lean because of the increased
efficiency. I usually add about 4-5psi on a fairly stock car.
4" would require more. It makes more power.
A afm or maf can measure the additional air flow and add the fuel through a load calculation. If you raise the fp you most likely will run rich.
06-17-2005, 02:47 AM
#124
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Originally Posted by stewardx
You can install a 3" on the car, and if you don't add fuel, it may
in fact hurt the performance. It's lean because of the increased
efficiency. I usually add about 4-5psi on a fairly stock car.
4" would require more. It makes more power.
Wes
in fact hurt the performance. It's lean because of the increased
efficiency. I usually add about 4-5psi on a fairly stock car.
4" would require more. It makes more power.
Wes
06-17-2005, 02:50 AM
#125
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No you are not leaning it out, increasing the base pressure increases the AFR across the board... I wont have issues with more boost resulting affecting fuel as I have MAP.
06-17-2005, 02:54 AM
#126
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Yes, you do.
The argument/proof was that you are running more rich at idle but at higher rpm with load you are actually running leaner (with less fuel pressure). Do a search and don't discuss with me. Its there.
The argument/proof was that you are running more rich at idle but at higher rpm with load you are actually running leaner (with less fuel pressure). Do a search and don't discuss with me. Its there.
06-17-2005, 03:19 AM
#131
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Originally Posted by turbo951fan
I explained it. If you increase FP at idle it will fall off at higher rpm. I am not an engineer, you are, so explain it!
I don't see it. The FPR will raise fuel pressure 1 for 1 with manifold pressure. Unless the stock fuel pump is reaching its limits then I don't understand how fuel pressure would fall off.
06-17-2005, 05:29 AM
#132
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how in the world would fuel pressure drop off?
People run fpr's all the time on our 951's because they increase the fuel pressure across the board. The stock fuel pump is good to 380rwhp or so even with stock pressure(2.5bar)
The problem with a fpr is its a real band aide way to add fuel...yes its effective but, you really need to buy larger injectors....that way you can lean or richen the mix how you see fit. A fpr just raises the rate all across the board.....now way to fine tune that. With bigger injectors and a fuel controller you could get the mix just right if you wanted too.
Whoever told you a fpr gives more fuel down low but, gives less up top didnt know what they were talking about. Sorry.
People run fpr's all the time on our 951's because they increase the fuel pressure across the board. The stock fuel pump is good to 380rwhp or so even with stock pressure(2.5bar)
The problem with a fpr is its a real band aide way to add fuel...yes its effective but, you really need to buy larger injectors....that way you can lean or richen the mix how you see fit. A fpr just raises the rate all across the board.....now way to fine tune that. With bigger injectors and a fuel controller you could get the mix just right if you wanted too.
Whoever told you a fpr gives more fuel down low but, gives less up top didnt know what they were talking about. Sorry.
