High rpm @ 70mph
- Thread starter shrek2
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Soldato
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- 2 Mar 2004
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A Hyundai coupe should idle at around 750RPM. If it's reading 1200, that's approximately a 60% over-read.
At your indicated 4500RPM at 70, when you say it should be around 3000RPM, that 60% over-read would mean that the engine's actually doing 2700RPM - close to the 3000 you recall.
Unless the engine note sounds higher than it should be (which would be pretty obvious, plus it'd probably be running hotter at that kind of sustained RPM), I'd be inclined to start with the rev counter
You can easily get a local indy to check the rev counter readings and what the engine's actually doing
At your indicated 4500RPM at 70, when you say it should be around 3000RPM, that 60% over-read would mean that the engine's actually doing 2700RPM - close to the 3000 you recall.
Unless the engine note sounds higher than it should be (which would be pretty obvious, plus it'd probably be running hotter at that kind of sustained RPM), I'd be inclined to start with the rev counter
You can easily get a local indy to check the rev counter readings and what the engine's actually doing
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My clutch did that when it wore out. Like you say -its bizarre.
Have you tried going faster? Try 140 or so and see what the RPM is.
Not really the easiest way to test is it?
Why not? He's happily done 100, so a bit more isn't going to harm. It could all be over and done with, from 70, in less than 60 seconds and a mostly empty road.
Not sure where you live but try finding an empty road long enough to do 140mph on in Wales safely.
I've driven at 140 in Wales before, in the Bangor area (I have a good friend who is going through her PhD there).
If he doesn't drive at 140, try 120. The point of the exercise is to verify whether it can drive "through" the limiter. If it can, it's just the rev counter being weird.
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Soldato
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sounds like clutch or wrong gear. my focus is at about 5k rpm in 3rd at about 70. 
If it's idling at 1200rpm and sitting at 4500rpm at 70 then surely it's easier to just nail it in a lower gear first and see what happens?
LoL. No way. License losing speeds. The only place I can think of to do 140mph is on Anglesey after the Llangefni junction at 3am but its too quick for me. I mean doing 100 scares the hell outta me. LoL
If it's slipping it won't get to 140. If it isn't slipping then 140 will be fine.
Wouldn't be anywhere near as much fun!If it's idling at 1200rpm and sitting at 4500rpm at 70 then surely it's easier to just nail it in a lower gear first and see what happens?
Now that I've re-read this, do you mean that as you approach 100 the RPM suddenly increases toward the redline (which is what I assumed - meaning knackered clutch), or that the RPM goes up proportionally with speed but is simply reading too high everywhere?
If the latter, is this a sudden change, i.e. one day it was fine, the next it was over-reading? Had any work been done on the car prior to you noticing this, such as a change of instrument cluster?
