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Manual SC400 shift points

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Old Jul 29, 2010 | 11:18 AM
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Default Manual SC400 shift points

I got a quick question about shifting in an SC400 (for those who hooked up their 1UZ's to either a 5-speed or 6-speed manual). I was talking to my friend who drives an 08' G37 coupe about shift points (his car's the 6-spd manual). When he's driving normally, he usually shifts at around 3k rpms and never lets it drop below 2k. He seems quiet convinced that if it did, the engine would stall.

For those of you who drive SC400's with the 4-speed autobox, you know that under normal driving, the car upshifts rather quickly. In fact most of the time when I'm driving normal, the engine usually hovers around 1300-1700 RPMs around town, rarely going above 2k. I was wondering if sometime down the road I were to swap in a manual tranny, would I have to rev higher to keep the engine from stalling?

BTW: If it makes any difference, I read online somewhere that the 1UZ produces 90% of its peak torque at as low as 1,000 RPMs.
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Old Jul 29, 2010 | 04:12 PM
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From: fl
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You can idle around in gear (on flat land) in almost any car. Your friend is paranoid. As for the last part, I know it's a little over 80% for the 1st gen 1uz in the SC's so 90% would probably be a reasonable estimate for vvt versions.

Last edited by BartleDoo; Jul 29, 2010 at 07:46 PM.
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Old Jul 29, 2010 | 07:04 PM
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Originally Posted by BartleDoo
You can idle around in gear (on flat land) in almost any car. You're friend is paranoid. As for the last part, I know it's a little over 80% for the 1st gen 1uz in the SC's so 90% would probably be a reasonable estimate for vvt versions.
I dont have an sc but i have a manual on a 1uz and i idle all the time when slow speeds are in need. its accually sorta hard to stall a 1uz If i want to go for it i shift at just under my 7500rpm rev limiter. (aftermarket computer.)
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Old Jul 29, 2010 | 07:53 PM
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Originally Posted by JakeBreyck
I dont have an sc but i have a manual on a 1uz and i idle all the time when slow speeds are in need. its accually sorta hard to stall a 1uz If i want to go for it i shift at just under my 7500rpm rev limiter. (aftermarket computer.)
Lucky bastard. Oh and my clutch started slipping Jake and I immediately thought it was Mr. Howe. lol. It turned out my clutch pedal adjustment bolt was just threaded too far, though. Super relieved and my clutch grabs a ton better now. It was a couple sad days for me, though, driving like grandma.
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Old Jul 29, 2010 | 07:59 PM
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It sounds like you're friend had a tramatic stall experience or something.

Shifting below 2 will only cause the car to studder but will not cause it to stall unless he is really trying to.

If it really did all the car company's would be hounding the car
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Old Jul 30, 2010 | 12:08 AM
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I drive all the time at 1000rpms in a gear when traffic is gay as **** (tampa)
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Old Aug 1, 2010 | 10:26 AM
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Your friend should trade in his manual for an auto. I don't know why he would think that the car would stall below 2,000 rpm. A car will only stall if the load is high enough to pull it down to or below the idle speed.
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Old Aug 1, 2010 | 01:25 PM
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lol ive definitely played around in the 200-300rpm range in 5th... the car wants to pull its self back to the normal idle speed... This is on a 1uz... I dont recommend doing this over and over as the bearings dont enjoy this... but still... it doesnt stall.
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Old Aug 1, 2010 | 02:13 PM
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Short answer you won't have to rev higher to keep your engine from stalling.
In my W58 SC400, around town just putting around I will drive in whatever gear gives me the speed I want at low RPM, around 1200-1500. If I want to accelerate or am going to go up a hill I downshift, although there seems to be enough torque to accelerate slowly and smoothly from 1500 in any gear. I will be more aware of the RPMs to see what the scoop is, cuz come to think of it I don't look at the tach that much, just shift by feel and sound. If the car feels sluggish, downshift before accelerating or when accelerating shift a little later. No voodoo in this.
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