Question about my gears and the Jet SCU....

[nitrox28]

I went from 3.08 gears to 3.73 gears. A member has a Jet SCU for sale, but from what I understand it only works up to 3.42 gears. Is it even worth buying? Does anyone know how I can get everything re-calibrated from my gear install? I'm still kinda new to all of this. THANKS!!!

[nitrox28]

Anyone??

[dstrbd1]

i did the same thing and the scu2000 didn't work for me at all.

[Dekay]

The SLP calibrator is supposed to work w/3.73s but I'm havin a God awful time making it work though..

[SLOWBRAEATER]

what you will have to do is go to a junkyard and get a pcm form a 3.8 of the same year as your that came with 3.42 y87 option from the factor and hen the scu will calibrate for 3.73 gears, if you try and use a 3.08 pcm you will hit rev limiter

[foshizl]

judging by how the settings are on the scu i think it will work, also it removes the rev limiter so that wont be a problem im interested to know if this will work.

[SkAchilles]

It am sure can work, just set it for the 3.08-3.42 gear change, then set the tire size to smaller than stock. Using a smaller tire can give the same effect of a higher gear ratio. Bad thing is it will make your shift points at WOT after the 6200 rev limiter I am pretty sure.

I am using it for my 3.42 swap, but I am almost positive that changing the tire size can make up for the difference.

[foshizl]

but on the mod settings 3.73s are an option...
stock tire dial 0 - 245 x 50 x 16
1 - 275 x 40 x 17
2 - 215 x 60 x 15
3 - 235 x 55 x 16
4 - 255 x 50 x 17

stock gear dial 0 - 2.56
1 - 2.73
2 - 2.93
3 - 3.08
4 - 3.23
5 - 3.42

modified tire dial tire size
0 - 23
1 - 24
2 - 25
3 - 26
4 - 27
5 - 28
6 - 29
7 - 30
F - Default

modified gear dial 0 - 2.56
1 - 2.73
2 - 2.93
3 - 3.08
4 - 3.23
5 - 3.42
6 - 3.73
7 - 4.10
7 - Default

if you look at the stock 3.08 is an option also mod setting 3.73 is an option thats why i think it will work anyone disagree? (of course im going on logic im acctually waiting on figuring this out so i can get one)

-- I also emailed jet, will fill in when i get a reply --

[ May 20, 2003: Message edited by: foshizl ]</p>

[Riles]

I have the JetSCU2000 with my 3.73's, and the short answer is "yes".

The slightly longer answer is that you have to do a little fine tuning- I found that directly setting the 3.73 ratio over-corrected for the gears. But, I have a GPS, so I set the gears to 3.42, and changed the tire size settings.

This is on a manual, though, so I dont know about autos.

[SLOWBRAEATER]

<blockquote>quote:</font><hr>Originally posted by Riles:
I have the JetSCU2000 with my 3.73's, and the short answer is "yes".

The slightly longer answer is that you have to do a little fine tuning- I found that directly setting the 3.73 ratio over-corrected for the gears. But, I have a GPS, so I set the gears to 3.42, and changed the tire size settings.

This is on a manual, though, so I dont know about autos.<hr></blockquote>

I find this very hard to believe because the scu2000 only works on autos not manuals, honestly i dont care what the directions say about it working for 3.73 gears, ive had the scu2000 and without having 3.42 gears stock or going and buy a pcm that is out of a 3.42 v6 then you will just hit the rev limiter a bunch of times. and if you have 3.08 gears stock and you set the scu2000 for 3.42 gears stock than your speedo will be off so to do it right you need 3.42 from factory or get a 3.42 pcm

[foshizl]

Why do people keep saying it will hit the rev limiter. the description says

"Interacts with the vehicle speed sensor on your Camaro/Firebird. It allows transmission shift points and speedometer calibration for vehicles where tire size or gear changes are required. It also eliminates the top speed limiter in these applications. It simply plugs in to the transmission and is adjusted with the turn of a switch."

so in conjunction with removing the top speed eliminator it is supposed to readjust the rpm that it shifts at to fix hitting the rev limiter..

common sense would lead you to believe that if the limiter is eliminated, it would be impossible to hit the rev limiter, right?

even so what is the rev limiter at on a car with 3.08 as opposed to one that has 3.42
[ May 26, 2003: Message edited by: foshizl ]

[ May 26, 2003: Message edited by: foshizl ]</p>

[Nachius]

<blockquote>quote:</font><hr>Originally posted by foshizl:
Why do people keep saying it will hit the rev limiter. the description says

"Interacts with the vehicle speed sensor on your Camaro/Firebird. It allows transmission shift points and speedometer calibration for vehicles where tire size or gear changes are required. It also eliminates the top speed limiter in these applications. It simply plugs in to the transmission and is adjusted with the turn of a switch."

so in conjunction with removing the top speed eliminator it is supposed to readjust the rpm that it shifts at to fix hitting the rev limiter..

common sense would lead you to believe that if the limiter is eliminated, it would be impossible to hit the rev limiter, right?

even so what is the rev limiter at on a car with 3.08 as opposed to one that has 3.42
[ May 26, 2003: Message edited by: foshizl ]

[ May 26, 2003: Message edited by: foshizl ]<hr></blockquote>


You understand this all wrong

It gets rid of the TOP SPEED limiter not the rev limiter. secondly these people actually have experience with the product not just the what the manufacturer claims. I had an scu2000 from 3.08s to 3.42s and banged off the rev limiter A LOT before I tweaked it a whole lot. I have 17" rims with 245's on them as well which shouldn't throw it off THAT much but still made a differance. I just kept moving the tire size up 1 notch, doing a WOT run, moving it again......Until I quit hitting the rev limiter.......

I would think you could do close to the same with 3.73s but I agree getting a 3.42 programmed PCM may make it a little eaiser!

[Riles]

<blockquote>quote:</font><hr>Originally posted by SLOWBRAEATER:


I find this very hard to believe because the scu2000 only works on autos not manuals<hr></blockquote>

Unless GPS's have some strange connection with my rear end and get thrown off as well (no way, ever), my speedometer is correct. It reads with less than 1% error. This is more accurate than alot of new cars rolling off the lots, including BMW and Mercedes.

It DOES work with the 3.73's.

Since I don't have an auto, I can't touch on shift points, but as far as the speedometer goes, the unit works.