1989 12 valve 6bt auto tranny 3.07 rear end gears how much is to much? good cruise? is there also a rpm governor or no ?

 

Check out this page for info about different ratios vs RPM. Take note of those that have OD, because if you don't you will need to use one lower than the highest gear.<br>http://www.dodgeram.org/tech/specs/axle/rpm_vs_mph.htm<br><br>Chris

 

that helps alittle, but is 3000 , 3200 to much or what, it runs 2600 now but thats full throttle if i up the power it will run more right or are they rpm limited ?

 

My 99 red lines at 3500, and the tach only goes to 4000. That's the thing about diesels, they have so much torque you can use taller gears in them and tach them out less to get the same performance. No, it probably will not be as responsive as a gas engine, just due to the turbo spool up, but if you talk to someof the guys here you'll find that their diesels can stomp many gassers, and with the tall gears. Heck, I'm thinking about putting in taller gears than the 3.54's I have now.<br>And the fewer RPMs you run when cruising, the better it is for the engine.<br><br>Chris

 

I posted in one of your other threads but I'll jump in here too, if you don't mind...<br><br>The normal governed speed on these 1st Gen trucks ranges between 2400-2600 RPM. So, you're right in the ballpark<br>You can run them up to as much as 3000 RPM without too much concern, assuming that your not running it there for 12 hours a day, in my opinion. (I'm a bit conservative ususally)<br>There are a number of guys running these trucks as high as 32-3300 even 3400 RPM. I know one 1st Genner (nascar mark) aka 'Wildman' who has run his upwards of 3600 RPM, but that was on the track and he beat a number of 2nd Gens doing it. I honestly think that if you plan any extended use over 3000-3200 RPM then you should have the springs changed and put in the 60 lb springs. Get a firm valve set too.... tight .020 and tight .010<br>Since you don't have an OD you'll run higher RPM's than us guys with OD, but atleast you have slightly lower gears to help with that. I believe (like mine) your tranny is 1:1 in 3rd, but I'd have to check to be positive.<br><br>Is that any help at all??? Drop me a note if need be, I'll help were I can...<br><br>bob.

 

no that was great you guys rock, that helped me i wont be running it over 2900 thats 83-85 mph and i dont need a ticket but 75 is perfect and thats like 2700 so im good to go, now i just need more power, but she runs good and my tach was correct so thansk guys

 

[quote author=CHAD22 link=board=13;threadid=8941;start=0#86206 date=1041269443]<br>no that was great you guys rock, that helped me i wont be running it over 2900 thats 83-85 mph and i dont need a ticket but 75 is perfect and thats like 2700 so im good to go, now i just need more power, but she runs good and my tach was correct so thansk guys <br>[/quote]<br><br>If you're looking for more power you should be talking to these guys with 12v engines. I don't personally know because I have a 24v, but I have heard that they can make more power than a 24v for cheaper. Go inot the Fits Gen. Engine and Drive Train and ask some questions there.<br><br>Chris