Installed 4:30's, how do I calibrate my speedo with several influential mods?

[Dusstbuster]

Fix for the extra miles:


Jack the rear end of the car up, put it in reverse, place something on the gas pedal and let it run in reverse for a couple minutes. Problem solved

 

[merc123]

The speedcal directions look hard but it's really not. I think it took me 15 minutes to do it after I figured out where the VSS was.

 

[merc123]

Fix for the extra miles:


Jack the rear end of the car up, put it in reverse, place something on the gas pedal and let it run in reverse for a couple minutes. Problem solved

If you do that and get to doing about 100, you can do 1,000 miles in 10 hours. It would take me 2 days to get to a decent mileage

 

[Mustang5L5]

WHat size tires are you running. That is a more important question than just knowing the wheels are 18". With the right size tire, the overall diameter of the wheel stays the same and there is no need to compensate the speedo.

You still need to do it for the gears however

 

[tmoneyballin]

I got a blowout the other day because I wanted to throw my Saleen rims back on KNOWING they were bald, got two days until I hit something in the road that shredded one! I will have as of next Monday, 255/35/18's in the front and 285/35/18's Nitto's. I don't know if that helps, or if you need more info, but I really appreciate it guys. I am putting the Tokico's on Today or Tomorrow and I figure I will order this part and install it next week when I am messing around with installing the new tachometer I got. Plus my friend said he is going to install his Tach first on his 96 Cobra and let me know if he has any problems - which is cool because when we install mine - we will do it twice as fast, with no problems!

 

[tmoneyballin]

Also it had a 4:10 in it before the install and I am questioning if that was an accurate speedometer - which if it was I may already have a speed call on the car that could be recalibrated??? Let me know if that is possible and the easiest way to check. Thanks guys, trust me you are helping a lot!

 

[Dusstbuster]

If there is a speedcal on the car the best way to check would be either a) jack the car up and see if there is a decent clump of wires going from the VSS connector up into the shifter area or b) pull the trim off around the shifter boot and see if there is a speedcal tucked in around there.

 

[tmoneyballin]

Thanks man, It dawned on me, either the guy never got it calibrated, or there could possibly already be one installed! Are there any other manufacturers that could be possible used by the previous owner or is this the main company?

 

[Shiroelex]

As far as I have ever known, that was the only way to calibrate a 5 speed, aside from getting the computer flashed or adjusted with a handheld. If you're positive you have bigger gears, I'd just try the good old 'pace a friend' method, to see how close your speed is to theirs. If it's accurate with theirs, and you don't see a speedcal, then you might just have a tune or flash.

 

[Mustang5L5]

I got a blowout the other day because I wanted to throw my Saleen rims back on KNOWING they were bald, got two days until I hit something in the road that shredded one! I will have as of next Monday, 255/35/18's in the front and 285/35/18's Nitto's. I don't know if that helps, or if you need more info, but I really appreciate it guys. !

Stock 245.45.17 = 25.7" diameter

255/35/18 = 25.0"
285/35/18 =25.9"


It's close enough on the rear size that the speedo won't be off much. We are talking maybe a tenth of a MPH at 60MPH.

However your front and rear sizes are almost an inch apart. That may mess with the ABS and cause the system to shut down. Unsure if it will however. Either way you may want to try to match the sizes better

a 255/40/18 would be 26.0" in diamter and only off by 0.1".

A 265/35/18 would be 25.3" in diamter

Here's a good place to mess around and figure things out.
http://www.miata.net/garage/tirecalc.html

 

[Dusstbuster]

As far as I have ever known, that was the only way to calibrate a 5 speed, aside from getting the computer flashed or adjusted with a handheld. If you're positive you have bigger gears, I'd just try the good old 'pace a friend' method, to see how close your speed is to theirs. If it's accurate with theirs, and you don't see a speedcal, then you might just have a tune or flash.

Tunes don't adjust for gears on his year vehicle...it would have to be a speedcal unless they switched the speedo gear.

 

[Shiroelex]

I didn't think 5 speeds had the same setup with the speedo gear, that old AODs did. I could be wrong, though.

 

[tmoneyballin]

Thanks guys! We are installing the Tokico 5 - Way's Tonight or some time this weekend. We are going to check to see if there is a speedcal. Also going to install a couple of tachometers. Should be fun!!! Yeah about the tire advice, I already ordered them and they come in Monday so I don't think I can really change the front's at this point in time.

Thanks again!

 

[GToddyT5]

Also going to install a couple of tachometers.

 

[tmoneyballin]

Yeah by "couple" I mean my 98 cobra and my buddies 96 cobra. He has his mounted with power, but never hooked up the wires - so he said he'd hook his up first to make sure "we" knew what we were doing and then we are going to install mine the same way if it works.

It's kind of like cleaning the IMRC's he helped me clean mine(the "donor" car) and now that he knows its relatively easy I will help him clean his. Only value exchange is the host car owner buy's the beer

 

[GToddyT5]

OK, thought you were putting two in the same car, one for the passenger, one for the driver...lol.

 

[tmoneyballin]

HAHAHHAHA That would be "Ghetto"... Some skeptical friend says "you didn't hit 7 grand on that shift" be like BullS*%&T look at your damn tach next time!

 

[blackfang]

I have already stated that a tune will not work for his car. They only work for 99+. There was also another company back in late 99/00 that made a device that recalibrated the speedo's and it is the Abbot ERA. I had it on my 99 Cobra when Mike Murillo installed the 4.10's on my 99 Cobra. However I dont think that works on cars that are pre 99.

I have my own instructions on my site to install the speedcal. Pretty much the same as DMP. I have installed them in under 20 minutes. The VSS is the tricky part as you have to remove and install the clips.

As for location of it, it is on the drivers side of the transmission.

Please stay away from Autozone. I installed new struts for a friends lowered 95 GT and she decided to go with stock struts. Well we went to AZ, and I asked for front struts for a 93 GT with a 5.0(as they are shorter and can work with this setup. They asked me, "Is that a 5.0?" I told them no a 454.

 

[tmoneyballin]

So we looked and their is no evidence of a speedcal even though the previous owner had 4:10's in it, since I could drop the car with the previous gear into 2nd going "60mph" I would assume he potentially never got it recalibrated. Does that make sense and in this case the speedometer was always off. Or do I need to worry about him switching a speedo gear and if so will that affect me recalibrating the correct speed with a speedcal?

I know regardless I need to buy one, but I am more curious if it will be exact when I calculate or will I have to pace and accurate car and keep dialing the right numbers.

Thanks

 

[blackfang]

He could have swapped the speedo gears themself. At 80mph, while in 5th gear, what rpm are you at? You should be at 3000 rpms at 80 mph in 5th gear.