Totally useless and goofy hp/torque questions

[SleeperZ]

Based on what I've read here on this site your 3.54 is the rear end you want for a turbo to help in building boost. A 3.54 will actually peel out easier than a 3.9 since it's gearing accelerates the wheel more(also from an old post). At 25 mph(2200 rpm) in my Z in 2nd gear, if I step on it my car won't start peeling out until I reach 35-37mph(3500 rpm). This is with 225/60/15 tires, 3.7 R200, and 1.94 2nd gear. DD2000 says I'm making 364tq at 3500, so in my case that's the limits of adhesion. Hope this helps.

 

Actually that's what I found extremely annoying about the 3.90 and crappy street tires (215/60/14). With the 3.90, I had a hard time NOT spinning the tires around town. I would just spool it slightly in a spirited manner, and the tires would let loose. With the 3.54 and the same tires, the wheelspin is much more manageable.

 

Plus, I can actually use 1st gear at the strip, without banging into the rev limiter before getting traction.

[Guest Z-rific]

Tire spin is based on so many variables, that I think a dependable formula for such would be impossible. As Scottie mentioned, the tire traction quality has much to do with breaking em loose. As does wheel tire size and condition, rim size, rear end gearing, tranny gearing.

 

Torque and horsepower would have to be measured at particular rpms, not just taking max of each. Cetainly, more is better. Also, engines that rev faster (lower rotating mass, smaller stroke, etc.) may get into the stronger rpm rangefaster, making it easier to spin tires.

 

A shift kit in an auto tranny, designed to shift REAL hard, will "chirp" the tires at shift without the need of a lot of hp or torque.

[A. G. Olphart]

If the clutch slips (aside from dragsters) odds are the tires won't have to.

How do things smell inside the car?

[Guest bastaad525]

80LT1 - I've seen a lot of dyno places dyno 5spd's in 3rd gear. And even if they only ever dynoed everyone in 4th, or whatever gearing was 1:1, I'm talking about the final ratio... that 1:1 still passes thru the diff and so can still end up being a different ratio from car to car. Not to mention when you bring tire size into the mix. I seem to remember reading somewhere that the differential has sort of a 'torque multiplication' effect, in the same way tranny gearing does, i.e. it's much easier to break the tires loose in a numerically higher first gear than 5th gear, which should equal more torque to the wheels in first, right? Then by the same token, doesnt a numerically higher differential equal more torque to the wheels for a given tranny gear ratio?

 

Heavy Z - I assure you dude, it's quite the opposite, this one I know from experience, it's always easier to spin the tires with a numerically higher diff (but once again, does that mean that the measured torque at the wheels is higher?)

 

Scottie - about lifting the front end, I"m talking about at speed, as opposed to from a launch from large amounts of power. I never actually left mine stock long enough to know, but I've heard many times that the stock front, lower valance/air dam of the 240z creates a lot of lift at high speeds, to the point that the front end would start to get light by 80-90mph. I'm wondering how much faster than that you'd have to go to get the front tires off the ground... a silly question, I know, but that's what this topic is for

 

A.G. Olphart - I'm running an ACT 6puck... no slip except for when I'm intentionally slipping it, and I've never yet smelled burning clutch, in this car or any car, as far as I know

 

 

So guys, how much hp to hit 150 or 160?