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Old 03 September 2014 | 09:53 PM
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Hey up peeps, as stated, first scooby I've owned, well turbo anyway... And will probably ask some standard questions u may find daft.
Just wondering.... At 70mph, where abouts should my rpm sit?
Cheers guys
Old 03 September 2014 | 09:55 PM
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depends on model/age/model spec/5 speed/6 speed
Old 03 September 2014 | 09:57 PM
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what year and model have you got?
Old 03 September 2014 | 09:58 PM
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Good point! Know little about my car tbh apart from '94 import, 5 speed, decat from turbo
Old 03 September 2014 | 10:26 PM
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not sure about the classics, my blob wrx is just below 3k rpm at 70mph

there isn't 1 figure that it 'should' be at, just go out and do 70, that's what your car will rev at at 70, you can just about find out what gearbox you have from the rev's too (work out the final drive ratio)

BTW, I don't know much about gearbox ratio's, I'm sure someone with more knowledge will be along soon
Old 03 September 2014 | 10:31 PM
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Daft question
Old 03 September 2014 | 10:32 PM
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Cheers Dave. I have a problem with the car idling at around 1400, think possibly a dodgy home made gasket, I'll take a pic in morning, so guessing it's leaking air, maybe the pic would help further to that problem, but at 70 I'm at 3400 rpm which I find excessive but could be wrong. It screams for a 6th gear when in excess of 80 (which I rarely take it to )
Old 03 September 2014 | 10:33 PM
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Cheers for input smiffy
Old 03 September 2014 | 10:36 PM
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Originally Posted by suprashep
Good point! Know little about my car tbh apart from '94 import, 5 speed, decat from turbo
Check your gearbox code on the VIN plate. Then you can go on Scoobypedia to find the matching gearbox code, which will give you the ratios and final drive. Then you can go on one of those calculating sites, enter the ratio(s) for 5th (and/or 4th gear), the final drive, your tyres size, and 70mph... Then you'll find your true rpm(s). Sorted.

Last edited by joz8968; 03 September 2014 at 10:45 PM.
Old 03 September 2014 | 10:39 PM
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Originally Posted by suprashep
Cheers for input smiffy
Sorry mate, bored watching England game, The smiley faces were supposed to show I was kidding with you hence using the same term you did.
Old 03 September 2014 | 10:44 PM
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Originally Posted by joz8968

Check your gearbox code on the VIN plate. Then you can go on Scoobypedia to find the matching gearbox code, which will give you the ratios and final drive. Then you can go on one of those calculating sites, enter the ratio(s) for 5th (and/or 4th gear), the final drive, your tyres size, and 70mph... Then you'll find your true rpm(s). Sorted.
If you give me the box's code and your tyres' size, I'll do it for you...
Old 03 September 2014 | 10:51 PM
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Originally Posted by smiffywhu
Sorry mate, bored watching England game, The smiley faces were supposed to show I was kidding with you hence using the same term you did.
I know mate got that, meant to add a smiley myself 😀
Old 03 September 2014 | 10:52 PM
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Originally Posted by suprashep
Cheers Dave. I have a problem with the car idling at around 1400, think possibly a dodgy home made gasket, I'll take a pic in morning, so guessing it's leaking air, maybe the pic would help further to that problem, but at 70 I'm at 3400 rpm which I find excessive but could be wrong. It screams for a 6th gear when in excess of 80 (which I rarely take it to )

an air leak won't change the gear ratio's
it sounds like you've got a close ratio box and that sounds about right. the newage wrx has got long gears, so 500 rpm more than mine seems fine.

the impreza is a fast point to point machine and the close ratio helps with the twisties, always in the sweet spot 4k-6k rpm . longer gears are better for crusing and better mpg
Old 03 September 2014 | 10:53 PM
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Originally Posted by joz8968
If you give me the box's code and your tyres' size, I'll do it for you...
Really? Brill, cheers for that! I'll get on with it Saturday morning as I got 2 more 13 hour shifts ahead so won't get chance until then 😪
Old 03 September 2014 | 10:57 PM
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Originally Posted by BoozyDave
an air leak won't change the gear ratio's
it sounds like you've got a close ratio box and that sounds about right. the newage wrx has got long gears, so 500 rpm more than mine seems fine.

the impreza is a fast point to point machine and the close ratio helps with the twisties, always in the sweet spot 4k-6k rpm . longer gears are better for crusing and better mpg
Ahh ok making sense... Just being my first turbo I wanna keep her sweet, don't wanna run it to the ground if something ain't right. The car is my daily while the supra has some bits done. Even then still gunna be my daily. As far as I'm aware the car is totally standard apart from zaust and coilovers. No gauges, turbo timer nothing
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