F35

Real tech discussion on design, fabrication, testing, development of custom or adapted parts for Pontiac Fieros. Not questions about the power a CAI will give.

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Atilla the Fun
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F35

Post by Atilla the Fun »

The '09 Cobalt SS turbocharged uses a Swedish 5-speed with optional limited slip differential. The gear ratios are: 3.38:1 first, 1.76:1 second, 1.18:1 third, 0.89:1 fourth, 0.70:1 fifth, and a 3.82:1 final. Shifting from first to second, the rpm drops to 52.07% of what it was before the shift. 2-3 is 67.04%, 3-4 is 75.42%, and 4-5 is 78.65%. In regular terms, IF Aaron was to use this, shifting at 7000 rpm, going into second he'd see 3645 rpm, third would be 4693, fourth would be 5280, and fifth would be 5506 rpm. IF Aaron used a 235/60R15 drag radial, that would be 42.11 mph in first gear, at 7000 rpm, 80.88 in second, 120.63 in third, 159.94 in fourth, and 203.35 mph in fifth, if he had the power and aero stability.
Cruise rpm would be 2238 at 65 mph.
Kohburn
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Post by Kohburn »

that looks better
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Aaron
I just wanna ride my motorcycle
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Post by Aaron »

Why do I always have to be the hypothetical? I don't have the money for this!

However, if I did, I wouldn't use that tranny. The 1-2 split is horrible for what I need, and the 5th gear is too tall. I'd want every gear change to leave me at 4500rpm or higher, that'd be perfect. And have 4-5 spaced much farther apart, that way I can do 75mph at 2,000rpm.
88GT 3.4 DOHC Turbo
Gooch wrote:Way to go douche. You are like a one-man, fiero-destroying machine.
The Dark Side of Will
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Post by The Dark Side of Will »

Aaron wrote:I'd want every gear change to leave me at 4500rpm or higher

Good luck with that...
Atilla the Fun
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Post by Atilla the Fun »

Kohburn, better than what? Aaron, we all know every detail of your car, so you're it. You would be lugging if you could gear it for 2000 at 75. An LS1 could do it, but not a DOHC 3.4 Heck, my '95 Z28 convertible with 2.73:1 and 4L60E could barely do it, it kept unlocking the converter until I switched to a 3.42:1 gear, which only cost me 2 mpg hwy. But I digress.
See my post in non-tech about other transmissions. I'm about to add more now.
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