mazzuri super headers
04-21-08, 04:45 PM
#496
Thanks for doing the test! PayPal sent.
I wonder how much of a role the altitude could be playing here. I also wonder if the issue might be due to the design choices that were made for the stock manifolds. Even as crappy as they are, maybe they are much better suited to the 350s than they are the 250s, which would make the headers much more beneficial to the 250s. ... These are just wild guesses...
I wonder how much of a role the altitude could be playing here. I also wonder if the issue might be due to the design choices that were made for the stock manifolds. Even as crappy as they are, maybe they are much better suited to the 350s than they are the 250s, which would make the headers much more beneficial to the 250s. ... These are just wild guesses...
04-21-08, 05:13 PM
#498
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04-21-08, 05:17 PM
#499
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Judging from the dyno it doesn't appear full throttle was applied until after 4300rpm. So the data to the left of 4300rpms may not be of much value. I assume 4th gear was used for all runs, but what mode was it in? (snow/norm/pwr)
You did gain some power though not much, so my only assumption is that the secondary cats and rest of the exhaust may be holding you back from the full potential of the headers.
Thank you from all of us for doing this unbiased testing.
You did gain some power though not much, so my only assumption is that the secondary cats and rest of the exhaust may be holding you back from the full potential of the headers.
Thank you from all of us for doing this unbiased testing.
04-21-08, 05:40 PM
#500
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Judging from the dyno it doesn't appear full throttle was applied until after 4300rpm. So the data to the left of 4300rpms may not be of much value. I assume 4th gear was used for all runs, but what mode was it in? (snow/norm/pwr)
You did gain some power though not much, so my only assumption is that the secondary cats and rest of the exhaust may be holding you back from the full potential of the headers.
Thank you from all of us for doing this unbiased testing.
You did gain some power though not much, so my only assumption is that the secondary cats and rest of the exhaust may be holding you back from the full potential of the headers.
Thank you from all of us for doing this unbiased testing.
04-21-08, 07:04 PM
#505
Wow on the A/F ratio. You were lean until @ 6100 rpm. You'll never make any power at 14.0 even 13.5 is a little risky. 13.0 Will provide good HP numbers. I'd be a little concerned with how lean its running. The HP could be down because the ECU is seeing the lean cond. and pulling timing.
04-21-08, 09:24 PM
#508
Pole Position
hmm... disappointing i guess, we all had such hihg hopes but lets wait and see what daniel says/ is gonna do. Hopefully this can be adjusted. This my be selfish but for me this is a good thing, well now know the difference in design and restrictions between the two models.
On a happier note, you gained torque which as stated is better than high end HP and compared to every other mod for our car this is still the best mod for the car in dollar to power terms ( well that adepends on how many dynos you do,)
On a happier note, you gained torque which as stated is better than high end HP and compared to every other mod for our car this is still the best mod for the car in dollar to power terms ( well that adepends on how many dynos you do,)
04-21-08, 09:37 PM
#509
Pole Position
noob question:
how would one adjust the air / fuel ration since there is no ecu tuning. Does the ECU ned to adjust on its own? Will it over time?
are we saying the A/F curve is too flat and that it shoul decrease alot more alot earlier in the rpm range? or should the same slope remaing the same but just alot lower ont he graph?
how would one adjust the air / fuel ration since there is no ecu tuning. Does the ECU ned to adjust on its own? Will it over time?
are we saying the A/F curve is too flat and that it shoul decrease alot more alot earlier in the rpm range? or should the same slope remaing the same but just alot lower ont he graph?
04-21-08, 09:56 PM
#510
Lexus Test Driver
Wow so little gains for so much work AND becoming illegal. No thanks. I'll bet that if you just delete the cats off the stock headers you'll get the same or better gains.