Custom 3" Intakes on VQ35HR project....
#61
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From: Burlington, NC
If i were to stay with a shorty/test pipe combo, i'd stick with the berks. they have yet to fail me. plus ive seen several fitment issues with the art pipes. not knocking them though, i know the guys at motordyne know their ****
#62
My vote goes for ppe or obx lth, then the motor dyne xyz y pipe. With a electronic exhaust cut out for some extra bwahhhh.
Then the gtr manifold, 3.7l, and 272 cams, and some e85. Don't sell yourself short.
Then the gtr manifold, 3.7l, and 272 cams, and some e85. Don't sell yourself short.
#64
^^^ http://www.gtmotorsports.com/product...roductid=16935
Pretty sure it also fits a VQ35HR (don't quote me on that though)
Pretty sure it also fits a VQ35HR (don't quote me on that though)
#68
But all the bottom stuff is mucho expensive. And probably not worth it to most people.
Last edited by npr350z; 03-27-2014 at 07:56 AM.
#69
Lmao thats funny. I say anywhere from 5-10 whp. I wonder why your car gets lower numbers with gears. That is strange.
#70
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Not sure. Here is a quote from hot-rod.com I found
Will different final drive ratios affect the dyno readings?
Upgrades are available for many dynos that enable testing AWD vehicles like the Syclone an
This one's tricky. First, there are potential discrepancies because different gears have different inertia values, generate more friction, and change the amount of tire slip. Higher numerical gears tend to be more inefficient, so as gear ratios increase numerically, power levels tend to slightly drop, particularly on an inertia dyno. When torque is multiplied by steeper gears, tire slippage also tends to increase.
However, there's another, often overlooked, factor in the brew: rpm and torque are inversely related to calculating horsepower, so changing the rear axle ratio or testing in other than a 1:1 transmission gear seemingly shouldn't change the horsepower numbers. But this doesn't take into consideration the fact that changing gear ratios changes the engine's rate of acceleration. For example: We know that on an engine dyno, if you change a sweep test's acceleration rate from, say, 300 rpm/second to 600 rpm/second, the flywheel power number (bhp) drops due to the faster rate of acceleration. As an engine accelerates at a higher rate, the power required to accelerate the engine increases, and a greater portion is consumed before it gets to the flywheel. Going to numerically higher gear ratios-whether in the trans (testing in a lower gear) or in the rearend-is like increasing the rate of acceleration in a sweep test. Whether this actually changes a given chassis dyno's reported results depends on how the specific dyno manufacturer does its math. For the most consistent results, always test in the same trans gear (generally 1:1) and rebaseline the vehicle after a rear-axle ratio change.
Upgrades are available for many dynos that enable testing AWD vehicles like the Syclone an
This one's tricky. First, there are potential discrepancies because different gears have different inertia values, generate more friction, and change the amount of tire slip. Higher numerical gears tend to be more inefficient, so as gear ratios increase numerically, power levels tend to slightly drop, particularly on an inertia dyno. When torque is multiplied by steeper gears, tire slippage also tends to increase.
However, there's another, often overlooked, factor in the brew: rpm and torque are inversely related to calculating horsepower, so changing the rear axle ratio or testing in other than a 1:1 transmission gear seemingly shouldn't change the horsepower numbers. But this doesn't take into consideration the fact that changing gear ratios changes the engine's rate of acceleration. For example: We know that on an engine dyno, if you change a sweep test's acceleration rate from, say, 300 rpm/second to 600 rpm/second, the flywheel power number (bhp) drops due to the faster rate of acceleration. As an engine accelerates at a higher rate, the power required to accelerate the engine increases, and a greater portion is consumed before it gets to the flywheel. Going to numerically higher gear ratios-whether in the trans (testing in a lower gear) or in the rearend-is like increasing the rate of acceleration in a sweep test. Whether this actually changes a given chassis dyno's reported results depends on how the specific dyno manufacturer does its math. For the most consistent results, always test in the same trans gear (generally 1:1) and rebaseline the vehicle after a rear-axle ratio change.
#74
lol oh ok was about to sell that ****. Maybe this only happens on certain dynos. The quote mentioned inertia dynos.
#75
It's because some dynos wanna read at a 1:1 gear ratio. So with a higher gear in the rear it's like going in 3rd or 6th.I can't remember exactly, some one explained it to me before. It's that the ratio they factor with is slightly off. Idk I could be spouting some crap though.
#76
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I was actually trying to find a cheap open diff with the 3.5 in it just to throw in for the testing. But it's not that big of a deal. If my baseline is 290 with the stillens and I hit 300 with the 3" intakes, then I'm going to assume 313whp with a stock final drive.
#77
And I am interested in the results of this! If you see considerable results I might consider swapping my injen long tubes out to do the same thing.
#79
It's the 1:1 issue that confuses the dyno... With a different final drive gear in your rear, you'll never truly have 1:1 output of rpm for the dyno to read correctly. It's not the end of the world, you just have to assume with shorter or longer gears that you're putting out somewhat more than what the dyno says.