Re: ACCURATE SPEEDOMETER?
 

twaldron wrote:

Tracie wrote:

>>
>>
>> So, assuming that my speedometer is correct, running approximately
>> 2500 rpms in 5th gear at 65 mph will NOT hurt my engine or cause
>> increased engine wear? If I were to shift into OD (6th), what is the
>> approximate rpms that I should be running so as to not cause lugging
>> or increased engine wear?
>>
>> THANKS
>>
>
> Your minimal tire size increase likely made your speedo/odo more
> accurate as they tend to read high from the manufacturer. That way
> warranties expire sooner and manufacturers save money. I'd bet you are
> very close now. For fuel economy, use the highest gear you can while
> staying in the power band (not lugging). Lugging will become immediately
> apparent and you do it by feel, not by someone telling you what RPM to
> run. If you shift into too high a gear, you will notice a power response
> loss and ultimately your engine will lug. Downshift.
>
> tw

Jeep especially seems to like to have the speedometer high for some reason.

The largest stock tire that is listed for my 88 Cherokee on the sticker
is P225's, yet P235's make my speedometer accurate according to measured
'miles' and many GPS checks. The cops must think so too, because they
don't stop me.

Same for most TJ's. They 'do' list a 31 as the largest stock tire and
according to what has been reported here, that makes them accurate with
no t-case speedo gear change needed.

I don't know how it worked, but my 86 CJ7 is accurate with 33's. It was
4mph + off with 31's (reading 65, doing 60) when I got it.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:16:47 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>Your site appears to be totally useless garbage.
>
>No one 'knows' their freaking tranny ratio or their t-case ratio, most
>do good to have their tire size and gear ratio.
>
>'Comparing' tire sizes of old vs new to get a new speedometer reading is
>garbage. The old tires were 'not' certified to have the correct speed
>vs the gauge speed, so that is a GIGO situation. Garbage In Garbage Out.


The GIGO is you Kike, you call yourself a Jeep Guru and do not even
know what trany or gear ratios a NSG 370 6 speed has . A real Jeep
freak would know this stuff so that leaves you out. One thing
consistant about you is that things you do not understand (which is a
lot) you attack with BS. BTW, that link has a function for even
simpltons like you (if you are smart enought to use a tape measure) to
compute speedo error with new tire size. You never where one for math
and physics but a great one for BS. I still chuckle about your 3.31
power gears with 33's and not using OD anymore and getting in a big
twist about beable able to get in 4lo a lot (because of big tires and
tall gears) and 4 hi at any speed. Your comments are purely ego based
you should realy not be given anywhere near the advise you do because
about a lot of things you are quite clueless.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:16:47 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>Your site appears to be totally useless garbage.
>
>No one 'knows' their freaking tranny ratio or their t-case ratio, most
>do good to have their tire size and gear ratio.
>
>'Comparing' tire sizes of old vs new to get a new speedometer reading is
>garbage. The old tires were 'not' certified to have the correct speed
>vs the gauge speed, so that is a GIGO situation. Garbage In Garbage Out.


The GIGO is you Kike, you call yourself a Jeep Guru and do not even
know what trany or gear ratios a NSG 370 6 speed has . A real Jeep
freak would know this stuff so that leaves you out. One thing
consistant about you is that things you do not understand (which is a
lot) you attack with BS. BTW, that link has a function for even
simpltons like you (if you are smart enought to use a tape measure) to
compute speedo error with new tire size. You never where one for math
and physics but a great one for BS. I still chuckle about your 3.31
power gears with 33's and not using OD anymore and getting in a big
twist about beable able to get in 4lo a lot (because of big tires and
tall gears) and 4 hi at any speed. Your comments are purely ego based
you should realy not be given anywhere near the advise you do because
about a lot of things you are quite clueless.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:16:47 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>Your site appears to be totally useless garbage.
>
>No one 'knows' their freaking tranny ratio or their t-case ratio, most
>do good to have their tire size and gear ratio.
>
>'Comparing' tire sizes of old vs new to get a new speedometer reading is
>garbage. The old tires were 'not' certified to have the correct speed
>vs the gauge speed, so that is a GIGO situation. Garbage In Garbage Out.


The GIGO is you Kike, you call yourself a Jeep Guru and do not even
know what trany or gear ratios a NSG 370 6 speed has . A real Jeep
freak would know this stuff so that leaves you out. One thing
consistant about you is that things you do not understand (which is a
lot) you attack with BS. BTW, that link has a function for even
simpltons like you (if you are smart enought to use a tape measure) to
compute speedo error with new tire size. You never where one for math
and physics but a great one for BS. I still chuckle about your 3.31
power gears with 33's and not using OD anymore and getting in a big
twist about beable able to get in 4lo a lot (because of big tires and
tall gears) and 4 hi at any speed. Your comments are purely ego based
you should realy not be given anywhere near the advise you do because
about a lot of things you are quite clueless.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:16:47 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>Your site appears to be totally useless garbage.
>
>No one 'knows' their freaking tranny ratio or their t-case ratio, most
>do good to have their tire size and gear ratio.
>
>'Comparing' tire sizes of old vs new to get a new speedometer reading is
>garbage. The old tires were 'not' certified to have the correct speed
>vs the gauge speed, so that is a GIGO situation. Garbage In Garbage Out.


The GIGO is you Kike, you call yourself a Jeep Guru and do not even
know what trany or gear ratios a NSG 370 6 speed has . A real Jeep
freak would know this stuff so that leaves you out. One thing
consistant about you is that things you do not understand (which is a
lot) you attack with BS. BTW, that link has a function for even
simpltons like you (if you are smart enought to use a tape measure) to
compute speedo error with new tire size. You never where one for math
and physics but a great one for BS. I still chuckle about your 3.31
power gears with 33's and not using OD anymore and getting in a big
twist about beable able to get in 4lo a lot (because of big tires and
tall gears) and 4 hi at any speed. Your comments are purely ego based
you should realy not be given anywhere near the advise you do because
about a lot of things you are quite clueless.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:02:50 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>
>Yup, that is where my OD starts to have good power, over 75 mph.

Maybe with a tail wind and down hill it does otherwise it has got to
be a slug in OD under anything other than perfect condition but you
and your ego would never admit that. See to me OD is just another gear
to us all the time in a PROPERLY GEARED 4x4. But then you do not know
what that is either.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:02:50 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>
>Yup, that is where my OD starts to have good power, over 75 mph.

Maybe with a tail wind and down hill it does otherwise it has got to
be a slug in OD under anything other than perfect condition but you
and your ego would never admit that. See to me OD is just another gear
to us all the time in a PROPERLY GEARED 4x4. But then you do not know
what that is either.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:02:50 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>
>Yup, that is where my OD starts to have good power, over 75 mph.

Maybe with a tail wind and down hill it does otherwise it has got to
be a slug in OD under anything other than perfect condition but you
and your ego would never admit that. See to me OD is just another gear
to us all the time in a PROPERLY GEARED 4x4. But then you do not know
what that is either.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 12:02:50 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>
>Yup, that is where my OD starts to have good power, over 75 mph.

Maybe with a tail wind and down hill it does otherwise it has got to
be a slug in OD under anything other than perfect condition but you
and your ego would never admit that. See to me OD is just another gear
to us all the time in a PROPERLY GEARED 4x4. But then you do not know
what that is either.
-----------------
TheSnoMan.com

Re: Re: ACCURATE SPEEDOMETER?
 

On Mon, 17 Sep 2007 11:44:39 -0400, Mike Romain <romainm@sympatico.ca>
wrote:

>Running in the higher gear is the bad thing, not running in the lower.
>Lugging is bad.

It is bad running in a lower gear ratio when effective drive ratio is
to tall because of axle ratio and tire size because your ego and
pocket book does not know what is correct.

>
>'You' engine has it's own 'sweet spot' of the rpm where it seems to run
>the best with the best response and best mileage. That is usually where
>it likes to sneak to when you are not paying attention.

Your sweet spot depends a lot on load and effective gear ratio in
vehicle and the demands placed on engine to move it at a certain RPM

>
>In 'my' engine's case this is 2300 rpm. Anything below 2000 on the
>highway starts the 'lugging' process and causes engine 'ping' or a
>rattling noise under load.

I see you are too cheap to use 89 octane or better fuel to which is no
surprize. None of my vehicle ever even think about pinging at any RPM
because I NEVER use 87 in any of them except a old 79 J20 with 8 to 1
compression that was made for 87.


>
>1750 or my OD (5th) at highway speeds is way too low for my setup.

And you lake the understanding and comittment to fix it properly
because your ego and pocket book holds you back.

BTW, if you want to restart this fued I will tear you a new one
because you provide a lot of times to do it. The choice is yours. Your
little more than a BSing troll with abig EGO problem.
-----------------
TheSnoMan.com