I was curious what parts make the difference in HP between the MT and AT. I heard someone comment that it was the spacer in MT that gave it those gains so I was wondering if this is true and what other parts make this difference. Thanks

 

I believe it has a higher red line too. So you gain more HP in the higer RPM's

 

Intake runners (bottom plenum), ECU, VVT on both exhaust and intake sides. Some say even the rods and crank are different. This is coming from the 300 hp 350z, which should be the same engine as in the '05 6mt G35c.

 

BUMP


Does anyone have definitive evidence of the difference between the two motors?

 

Bottom plenum is different.... ECU is different .... different Gear ratios? ...there really isn't much of a performance difference...

 

Everything you guys said...

Plus...

Don't automatic transmissions lose 15% of power due to the Torque Converter not being as efficient as the Manual Tranny?

 

DING DING DING !

Correct. The torque converter is where most of the difference is. While stick cars have a direct and continuous connection between the engine and the wheels (vie clutch plates), the AT trannys are built as two turbine-shaped plates with fluid running in them. the loss of power is right there where it takes some massive force to spin the wheels-side plate using the turbulence cause in the fluid by the engine-side plate.

 

I believe it has different cams and valves as well. Think I read it in a 350z Brochure.

 

Your point is true of course there is even a little lower hp due to the AT.

It's not a factor in what is being compared- the crankcase horsepower of mt (298)vs. AT (280) The wheel hp of course is less and factors in drive train losses too.

 

Hey, tell me one thing then .. i've raced a couple of MT's... and i have an AT.... and it seems like .... end of my 3rd and the whole of 4th gear i start pulling on them ... and they aren't bad drivers... whats the reason for that?

 

They're so far ahead they let off.

Yes, I know it is an old thread but I just couldn't resist.

 

A worthy revival for a perfect riposte. It's sort of like thinking of the perfect comeback after the party's over and you're on the way home....

 

Not to get too technical but a direct comparison between the two types of transmissions is pretty much even on the quarter mile. The difference is found on a road course track where you're able to grab gears with better precision, decel, turn the car with the gas pedal, etc.

A 240whp car isn't going to see a very big margin of difference comparing either power train.