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I am gonna Dyno my car this Saturday to see how much HP the headers and cats gave me. Lets see who can get the better guess give it a shot guys.
 

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What were your old #'s? Are you gonna dyno it w/your 20's or will you put the stock rims on the rear?
 

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Personally, I'd dyno it both ways. With 20's then with stock rims and tires. I'm hoping to be at the dyno tomorrow for the great cold air intake challenge part deux, and I'll be doing that for at least a comparison. My first run will be as-driven. All others will be with the stock 17's. Bigger wheels weigh more and have much higher rotational inertia than the stockers. The motor has to overcome this, as well as accelerate the car's mass. It will make a difference, but how much is the question. It may be 'in the noise', but 'while your there', you might as well do the runs.
 

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odysseus said:
Personally, I'd dyno it both ways. With 20's then with stock rims and tires. I'm hoping to be at the dyno tomorrow for the great cold air intake challenge part deux, and I'll be doing that for at least a comparison. My first run will be as-driven. All others will be with the stock 17's. Bigger wheels weigh more and have much higher rotational inertia than the stockers. The motor has to overcome this, as well as accelerate the car's mass. It will make a difference, but how much is the question. It may be 'in the noise', but 'while your there', you might as well do the runs.
Ody - Tomorrow huh? Sweet, we've all been looking forward to this day!!!

Sorry SD, didnt mean to detract from your runs, but Ody's are going to be much more relavent to me. Oh, and I'll give SD about 240 RWHP.
 

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We should have some good data comparing the HP for stock wheels, 18's and 20's if we both can get runs in with different wheels. Marine, do you still have a set of stock wheels to try out?

For a happy meal, I predict 245 RWHP (around 290 at the crank) for the marine. I'm only hoping to break 200 RWHP for my runs tomorrow. :crying2:
 

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Discussion Starter #9
odysseus said:
We should have some good data comparing the HP for stock wheels, 18's and 20's if we both can get runs in with different wheels. Marine, do you still have a set of stock wheels to try out?

For a happy meal, I predict 245 RWHP (around 290 at the crank) for the marine. I'm only hoping to break 200 RWHP for my runs tomorrow. :crying2:
My stock wheels are 16's. I have to drive to L.A to pick them up but tomorrow is the Marine Core Ball so hopefully I will have time to run it with both.
 

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I'm usually slow to the obvious, but I figured out how to get two tires into the trunk of my car for my dyno runs. I simply pulled out the spare, dropped one in the hole, put the cover on, and put the second in the trunk, along with the 3 other airboxes I tested. I know everyone is saying 'duh', but I was thinking chase car/Jeep, to bring my stuff to the shop, until the light bulb dimly lit the night before.

Marine, if you can, make sure you test your car with stockers and 20's. As I found out yesterday, there is a measureable difference in RWHP due to the much larger rotating inertia of the bigger wheels, since it's based on the mass multiplied by the radius squared. I had a 4 RWHP loss going from 17's to 18's.

I'm anxious to see if it breaks 250 RWHP, (well over 300 at the flywheel).
 

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Discussion Starter #11
And the number is 238HP and 232 pounds of torque to the wheels.
 

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Can we get a little more info? Did you run the 20's or the 16's??? What were your #'s before the headers were put on?? Do you really think the headers made a big difference, number wise???
 

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Discussion Starter #14
05CTS said:
Can we get a little more info? Did you run the 20's or the 16's??? What were your #'s before the headers were put on?? Do you really think the headers made a big difference, number wise???
I only ran it with the 20's because I didnt have time to switch them out since it was the same day as the Marine Core Ball. the Headers and cats gave me a 35hp increase. I think if I was to run it with the stock wheels it would easily break 250hp. before headers I ran at 203 with the 20's
 

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SdMarineGuy said:
...the Headers and cats gave me a 35hp increase.
Wait only 238hp, that cant be right, Ody got 244 with just the K&N and a Borla.. 238 is an 18 hp jump not 35HP, 35 would bring u up to 255HP

am I just misunderstanding the numbers or what :bonkers:
 

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BishopRuger said:
Wait only 238hp, that cant be right, Ody got 244 with just the K&N and a Borla.. 238 is an 18 hp jump not 35HP, 35 would bring u up to 255HP

am I just misunderstanding the numbers or what :bonkers:
He's talking RWHP. I only hit 203 RWHP with the Borla, K&N, and stock wheels. That translates to 254 at the flywheel (34 HP over stock at the flywheel).

Marine is putting out around 298 HP at the flywheel (238 at the rear wheels)! Stock the 3.6L is rated at 255, so he's putting out around 43 HP over stock at the flywheel.

I wish Lund had made headers for the 3.2L. I think Pete added some to it too with the extrudehone and ceramic coating! 35 RWHP for headers and high flow cats . . . Wow.
 

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If you take the 20% drivetrain loss its 286 Crank Hp. And toss those 20" rims for a set of 16's you might see 290-295. Thats a real improvement SD, Salute!
 
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