LSX454:big intake swap, no change in power
#81
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In a good flowing setup with straight/light bends, I feel like it is indeed a restriction.
I say ditch it, go SD, and enjoy the gains.
Anyway, correct me if I'm wrong on any of that.
#83
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#88
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Drove the car today with a new speed density tune, as I unplugged the MAF just to try something new, and I'm not seeing much difference. I still dont know why I'm down on power, especially torque. I know my dyno charts are all in SAE vs how a lot of people show theirs in Standard, which usually shows a higher number. Still doesnt add up though. I guess I will throw in the fuel pump when it gets here and head back to the dyno, but I dont see how I will gain the 60-70 hp back. My fuel pressure does drop 20lbs up top, but it only drops a couple at peak torque so I dont think that's the issue. I should have big torque with this motor, especially considering the smaller cam.
#89
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I’ve seen probably over 100 posts about de-screening MAFs and have yet to see any consensus on the topic... my question would be how is the AFR maintaining when the fuel pressure is dropping off? That seems odd. What fuel rails are on there? And everything else between the pump and injectors? Also, I may have missed it, but how aggressive/conservative is the timing at WOT?
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Originally Posted by slowpoke96z28
I’ve seen probably over 100 posts about de-screening MAFs and have yet to see any consensus on the topic... my question would be how is the AFR maintaining when the fuel pressure is dropping off? That seems odd. What fuel rails are on there? And everything else between the pump and injectors? Also, I may have missed it, but how aggressive/conservative is the timing at WOT?
#92
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no updatesupdatethe car has been sitting. I'm ordering a new fuel pump here in the next week, then will work on re-tuning and going back to the dyno. From what I saw, the injectors weren't going static, and IDC hit around low 80%. Fuel pressure does drop a little over 10psi during a pull, but it did about the same thing with both intakes that I tested. The ported MSD LS7 did show higher airflow values, and I had to readjust my MAF curve to compensate. I still feel something else is contributing to the zero gain in power between two different intakes. The 10ish psi loss in fuel pressure cant be the only reason I got the exact same result with two intakes that had much different runner lengths. My dyno results were shown in SAE vs standard so I guess that can make a small difference in total power as I only made 528rwhp with this setup that should make noticeably more. Maybe my Nick William's DBW throttle body has an issue and is starting to close? I shouldnt hit 528rwhp and 518torque with these 2 very different intakes.
#93
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no updatesupdatethe car has been sitting. I'm ordering a new fuel pump here in the next week, then will work on re-tuning and going back to the dyno. From what I saw, the injectors weren't going static, and IDC hit around low 80%. Fuel pressure does drop a little over 10psi during a pull, but it did about the same thing with both intakes that I tested. The ported MSD LS7 did show higher airflow values, and I had to readjust my MAF curve to compensate. I still feel something else is contributing to the zero gain in power between two different intakes. The 10ish psi loss in fuel pressure cant be the only reason I got the exact same result with two intakes that had much different runner lengths. My dyno results were shown in SAE vs standard so I guess that can make a small difference in total power as I only made 528rwhp with this setup that should make noticeably more. Maybe my Nick William's DBW throttle body has an issue and is starting to close? I shouldnt hit 528rwhp and 518torque with these 2 very different intakes.
I went to a larger low lash solid roller camshaft from a hydraulic and a mezeire electric water pump, more lift a slightly looser stall converter and now my power is lower.