Td5 – Max RPM in each gear? No tacho…

[GoldCloverLeaf]

I have yet to install a tachometer in my Td5 Defender, so out of interest i did a search for specifications in relation to the maximum speed possible for each gear selected, 1st, 2nd, 3rd etc, which would give me an indication of where redline is in each gear, not that i plan on drag racing it or anything like that :angel:

I know some manufacturers list this information ie: 2nd gear = 76km/h = presumably, redline in that particular gear.

I know there are variables such as speedo calibration, tyre size etc. but it would be good to know until i get a tacho... Anyone have the specs available?

[Josh_WA]

hey Buddy,

check this link

Ashcroft Transmissions - Ratio Calculator (http://www.ashcroft-transmissions.co.uk/calc/ratio_calc.html)

once you type in your tyre size ect. it will give you different values, it should give you a rough estimate of revs at certian speeds for each gear.

IIRC the TC ratio is around 1.4 and i think the diff ratio is 3.54 on a std 110

Cheers

Josh

[MR LR]

TD5's have a rev limiter anyway, so eventually you will find it (i know i have), but i have always driven my cars 'by the seat of my pants', in otherowrds, by listening and how they feel, you know when to change gears as you will feel paek torque, only reason i've ever looked at a tacho is if something needs to be kept under a certain number of revs (a Mack truck for example). Personally i wouldn't bother, but each to their own i guess. Just my $0.02

[Blknight.aus]

bout 4500rpm from memory, never really needed much over 3K rpm personally.

[Benny_IIA]

bout 4500rpm from memory, never really needed much over 3K rpm personally.

I thinks its 4850 to be exact:angel:...

My very tuned td5 will pull all the way to the rev limiter.

But I think if you need a tacho to drive you need to look at the driver rather then for a tacho.

[Blknight.aus]

so did big red, in 4th, with a ton trailer on the back going UP the toowomba range....

I hate my wife for putting me in the situation where it was big red or bankruptcy.

[roverrescue]

Dave "hate" is a very strong word.

Bankruptcy has its benefits - BUT you really need to do it properly and go large.
A 20k depreciating piece of rattly, leaky English dis-engineering is never going to be enough to go over on.
Therefore your wife is very wise and not one to be "very very very disappointed with"

One day soon you will have a big red again BUT you will still take 32 hours and 46 minutes to change a set of wheel bearings ;)

Steve

[Blknight.aus]

hey, no fair making me look bad with the rounding....

Everyone knows its 32 hours 45 minuts and 53 seconds.

Kindly count the same way as drag racers do, 7.9999999 seconds is still a 7 second pass

:D

[Blknight.aus]

Freaky, double posty thing, this one got killed

[GoldCloverLeaf]

Yes i'm not a complete moron i can drive without a tacho ;)

My Td5 is also tuned and the boost comes on strong when your foot is into it and have not hit the rev limiter before, not that i was planning to.

I usually upshift in the maximum torque zone low in the rev range but when i have reved it out on the odd occasion it always feels like it's still making good power but it sounds pretty busy so i chicken out and upshift, as i remind myself i'm driving a diesel powered rivited aluminium shed on 4 wheels :D

And i see your point, the only time i really look at the tacho in my other cars is when im heel-n-toeing a downshift to match revs, and this is almost phisically impossible in a Defender!

[Blknight.aus]

your feet are too small.

[Jitterbug]

Mine has a hard rev limiter that I can change on the fly. currently set at 5500 (V8). Great fun at the lights to rev it BAHHHHHHH-BA-BA-BA-BA-BA-BA.
No one suspects the 28 year old landrover to be making a noise like that :twisted:

[GoldCloverLeaf]

your feet are too small.

You know what they say about small feet... oh wait that doesn't work in my favour in this instance.

[vnx205]

I usually upshift in the maximum torque zone low in the rev range

Quite a bit of the time I change up at the speed that will still have the turbo making a useful contribution by the time I finally arrive in the next higher gear. :) So uphill with a headwind needs a few more revs.

I could probably work out what revs that would be, but as the speedo (like just about every other standard Defender) is out by 10%, it would involve calculations that I can't be bothered doing. If real Land Rovers (the ones with leaf springs) didn't have tachos, there is no reason why later ones should be fitted with a tacho. :D:D

I think the point I was trying to make was that often what has a significant influence on the upshift point is what the engine and turbo will be doing when you get into the next gear.

I'm sure you knew that. I was just trying to muddy the waters. :p:p:p

[GoldCloverLeaf]

Oh dear i hope people don't read this thread and think im clueless about how or when to upshift :p

I have no problem valve-bouncing a petrol engine at the limit but i doubt a diesel engine appreciates it as much!

*Goes for a drive to take note of rev limiter/speed achieved in each gear, just for sh*ts and giggles* not really

[Blknight.aus]

You know what they say about small feet...

absoutely

Men with big feet have big socks.

[Benny_IIA]

absoutely

Men with big feet have big socks.

and jocks :angel:

[cewilson]

And i see your point, the only time i really look at the tacho in my other cars is when im heel-n-toeing a downshift to match revs, and this is almost phisically impossible in a Defender!


I'm not sure what you mean, but I double clutch whenever I'm going down into second gear due to the synchro's being shot. Been doing that for years and I have no issue getting it in without crunching - hell it's easier than the Mack ;)

[GoldCloverLeaf]

I also double clutch more often than not in the Deefer but i do it in most cars out of habit.

Regarding the heel n toe reference there is a sweet spot in the rev range when down shifting which varies depending on the engine speed before the clutch is dipped. This can be done by ear and takes a lot of practice but if you set yourself up before a corner you can work out on the tacho roughly where this sweet spot is.

Say if i'm about to downshift under heavy braking (using my toes) i use my heel to bring the revs up to about 30% higher than whatever the current revs are under engine braking conditions.

Say if im at the end of a straight coming up to a corner at 6500RPM in 3rd and i want to brake and drop into 2nd gear before i accelerate out of the corner apex i will begin to brake with my toes until engine braking has reduced to say 4000RPM... then i will dip the clutch, bring the revs up with my heel to 5200RPM, then dip the clutch again and select 2nd... wait for the apex and accelerate out the other side of the corner.

If it is done quickly and accurately the syncro pretty much becomes redundant, as the layshaft speed has matched the output shaft speed... goes in like butter!

This can also be done with upshifts... although no need to look at the tach or anything just dip and release the clutch once, pause for X milliseconds and dip clutch and change gears, if it is timed right there should be little or no resistance when upchanging at any speed.

And if you aren't in a hurry, you can upshift with no clutch at all, that is always fun but its usually in the 1500-3000rpm range depending on the car.

Anyways this is a 4wd forum not a racing forum so never mind me got carried away :angel: