Notices
ScoobyNet General General Subaru Discussion

random rpm question

Thread Tools
 
Search this Thread
 
Old Sep 3, 2014 | 08:53 PM
  #1  
suprashep's Avatar
suprashep
Thread Starter
Scooby Regular
 
Joined: Aug 2014
Posts: 78
Likes: 0
From: hull
Default random rpm question

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
Reply
Old Sep 3, 2014 | 08:55 PM
  #2  
BoozyDave's Avatar
BoozyDave
Scooby Regular
15 Year Member
Liked
iTrader: (8)
 
Joined: Sep 2008
Posts: 2,208
Likes: 3
From: Rotherham - ENGLAND
Default

depends on model/age/model spec/5 speed/6 speed
Reply
Old Sep 3, 2014 | 08:57 PM
  #3  
BoozyDave's Avatar
BoozyDave
Scooby Regular
15 Year Member
Liked
iTrader: (8)
 
Joined: Sep 2008
Posts: 2,208
Likes: 3
From: Rotherham - ENGLAND
Default

what year and model have you got?
Reply
Old Sep 3, 2014 | 08:58 PM
  #4  
suprashep's Avatar
suprashep
Thread Starter
Scooby Regular
 
Joined: Aug 2014
Posts: 78
Likes: 0
From: hull
Default

Good point! Know little about my car tbh apart from '94 import, 5 speed, decat from turbo
Reply
Old Sep 3, 2014 | 09:26 PM
  #5  
BoozyDave's Avatar
BoozyDave
Scooby Regular
15 Year Member
Liked
iTrader: (8)
 
Joined: Sep 2008
Posts: 2,208
Likes: 3
From: Rotherham - ENGLAND
Default

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
Reply
Old Sep 3, 2014 | 09:31 PM
  #6  
smiffywhu's Avatar
smiffywhu
Scooby Regular
 
Joined: Feb 2014
Posts: 368
Likes: 0
From: Lowestoft
Default

Daft question
Reply
Old Sep 3, 2014 | 09:32 PM
  #7  
suprashep's Avatar
suprashep
Thread Starter
Scooby Regular
 
Joined: Aug 2014
Posts: 78
Likes: 0
From: hull
Default

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 )
Reply
Old Sep 3, 2014 | 09:33 PM
  #8  
suprashep's Avatar
suprashep
Thread Starter
Scooby Regular
 
Joined: Aug 2014
Posts: 78
Likes: 0
From: hull
Default

Cheers for input smiffy
Reply
Old Sep 3, 2014 | 09:36 PM
  #9  
joz8968's Avatar
joz8968
Scooby Regular
15 Year Member
iTrader: (13)
 
Joined: Aug 2006
Posts: 23,764
Likes: 9
From: Leicester
Default

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; Sep 3, 2014 at 09:45 PM.
Reply
Old Sep 3, 2014 | 09:39 PM
  #10  
smiffywhu's Avatar
smiffywhu
Scooby Regular
 
Joined: Feb 2014
Posts: 368
Likes: 0
From: Lowestoft
Default

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.
Reply
Old Sep 3, 2014 | 09:44 PM
  #11  
joz8968's Avatar
joz8968
Scooby Regular
15 Year Member
iTrader: (13)
 
Joined: Aug 2006
Posts: 23,764
Likes: 9
From: Leicester
Default

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...
Reply
Old Sep 3, 2014 | 09:51 PM
  #12  
suprashep's Avatar
suprashep
Thread Starter
Scooby Regular
 
Joined: Aug 2014
Posts: 78
Likes: 0
From: hull
Default

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 😀
Reply
Old Sep 3, 2014 | 09:52 PM
  #13  
BoozyDave's Avatar
BoozyDave
Scooby Regular
15 Year Member
Liked
iTrader: (8)
 
Joined: Sep 2008
Posts: 2,208
Likes: 3
From: Rotherham - ENGLAND
Default

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
Reply
Old Sep 3, 2014 | 09:53 PM
  #14  
suprashep's Avatar
suprashep
Thread Starter
Scooby Regular
 
Joined: Aug 2014
Posts: 78
Likes: 0
From: hull
Default

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 😪
Reply
Old Sep 3, 2014 | 09:57 PM
  #15  
suprashep's Avatar
suprashep
Thread Starter
Scooby Regular
 
Joined: Aug 2014
Posts: 78
Likes: 0
From: hull
Default

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
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
KAS35RSTI
Subaru
27
Nov 4, 2021 07:12 PM
slimwiltaz
General Technical
20
Oct 9, 2015 07:40 PM
IanG1983
Wheels, Tyres & Brakes
2
Oct 6, 2015 03:08 PM
Brzoza
Engine Management and ECU Remapping
1
Oct 2, 2015 05:26 PM
shorty87
Other Marques
0
Sep 25, 2015 08:52 PM




All times are GMT +1. The time now is 08:02 PM.