I have a 3.73 gears in my 93 z28 and the speedo is of course off. I tried to get it fixed through the process of the chip but since it is a 93 it cant be done like that. I am told that I can get something that goes in my rear end that will fix my problem but I dont know what it is or where to get one.

 

no you need a gear for the trans i believe, someone else will chime in with what it is exactly. i dont know pre OBDII too well

 

Dakota Digital SGI-5
http://www.summitracing.com/parts/DAK-SGI-5/

this will fix you right up.

 

I couldn't help but laugh at that statement.

 

Has anyone used this and is sure it will work with my 93?

 

ya i use this w/ my 4.10's and it work perfect.

 

How hard is it to use?

 

Ditto.

 

I dont think its too hard. prity much wat it dose is you cut the speedo wire and you hook it up to this. so it looks like this pcm-----dokota----speedo. the only tricky part is that its got like 4 slots so your not exactly sure witch to hook it up to. what i do is i get a friend to drive next to me and tell me how fast he is going while I use the *** on it to increase and decrease the speed on the speedo. if it still dosn't work i pull over and try a different slot and do the same thing over again till you find the one it needs. simple really.

 

All you have to do is get a new drive and driven gear for the transmission. Total of like $20. Just pop off the tailshaft housing and go at it. Did you go from 2.73s to 3.73s? You will need a 15 tooth drive gear and a 44 tooth driven gear I believe. I did the same thing.

 

BAHAHA I noticed that too!

You lucky bastard! I had to have my pcm recalibrated for that

 

That can only be done on us 93 auto's the manual guys have to use the box.

Speaking of which, what tranmissions does he have?

 

Well I hope he wouldn't swap from 3.42's to 3.73's for a 6 speed, but if its a M28 or whatever that came with the 2.73's, its understandable... I just assumed it was an auto since he went to 3.73's.

 

Good stuff.

The thing that goes in the rear to correct it is called a "Dickfer."

I had my speedo corrected during my dyno tune. It was off by 8 mph.

 

Mine was off by about 30%. I didn't correct it for a good 6 months either... so 80 mph on the highway = 3500 rpms since the car thought i was going about 110.. needless to say I didn't take the highway very often.

 

I'm assuming a few things here...
I know the 93's don't have a computer controlled tranny (Are they 700r4's then btw?), so does this mean the computer itself in the vehicle can't be tuned for the gears?

 

that is correct. you can't just tune the car in the 93's for a gear change.

 

gotcha...interesting stuff
learn sumthin new everyday