Rearend oil weights and MPG

-
What made you pick 30, and at what rpm does this come in at?
And, of course, what camshaft, more specifically do you know the ICA?
At your Scr, spark-knock should not be an issue unless the cam is really small, or the timing is coming in too fast, or your car weighs a lot more than the typical A-body, or your timing light is lying to you,or she is really really lean, or the stinking Vcan is interfering. Lol.
If you keep the 12 and 30 with no other changes, then IMO, the MSD will not change much if anything. Cramming timing at an engine solves nothing, Give her what she wants and no more. Just one degree into detonation will lose more power than 2,3 or even 4 not enough. Detonation is the engines enemy. But also IMO, 30 total is not enough power-timing.
The ECU has exactly two jobs; Job#1 is to receive the signal from the pick-up and modify it for Job #2, which is to trigger the coil to fire. It is nothing more than an interpreter and a glorified set of points. Well a bit more than nothing; there are no points to burn up and no rubbing block to wear off. If your car starts, runs, and revs to the proper shift-rpm, then it's doing it's job. I have run a 360hp 367 for several years on an old Orange box, and even now 20 years later, and 70hp more, I still have no need for a CDI MS system, altho I do run a different Amp.
IMO, your tune could just be a little better.
 
Slantsix64 said:
A/j the motor is 9:5 compression 3.55 gears 904 shift kit roller camshaft. I'm currently getting 13-14 around town with the 318 in the barracuda I know I can squeeze an extra mile in. I'm at 30 degrees total 18 in the dizzy and 12 initial if I bump up the initial I can hear spark knocking at idle I blame my cheap Ecu box hopefully upgrading to an msd box will allow to run more adnavce with no spark knock.i was als thinking of changing to 3.91s since. Do not do any highway driving
Click to expand...

I agree with AJ however you note you get knocking at idle, that's pretty much impossible... spark knock only happens under load, you must have something else going on? Also @AJ/FormS since you've had your Orange Box so long it's probably a "good" one, the ones made in more recent years are crap and if the OP's isn't a 25-year-old used piece it very well may be causing problems, ironically lol.
 
MopaR&D said:
I agree with AJ however you note you get knocking at idle, that's pretty much impossible... spark knock only happens under load, you must have something else going on? Also @AJ/FormS since you've had your Orange Box so long it's probably a "good" one, the ones made in more recent years are crap and if the OP's isn't a 25-year-old used piece it very well may be causing problems, ironically lol.
Click to expand...
I only used that Orange box for 3 or 4 years. I bought it in about 1997 or 98. But the car didn't hit the road for the first time, until late 1999. And the box got pulled perhaps in 2003, when I tried CDI, which failed right away. So then the Orange box came back on line while the CDI got warrantied. In the mean time I installed a Jacobs dash-mounted,dial-back, timing box, which had an Amp built in. And then I retired the Orange box again. And when the replacement CDI box came back to me, it went straight into storage, and is still in it's sealed shipping carton. I have never verified that it works.
Some years later I installed that Orange box on my brothers mid-70s Dodge camper van, which I saw last spring still hauling stuff.
 
Last edited:
If your rear has too much drag with 80w90, you need more horsepower. Then you wont notice or care :)
With the limited miles most of our cars will see it does not make sense to spend the extra money on synthetics.
 
AJ/FormS said:
What made you pick 30, and at what rpm does this come in at?
And, of course, what camshaft, more specifically do you know the ICA?
At your Scr, spark-knock should not be an issue unless the cam is really small, or the timing is coming in too fast, or your car weighs a lot more than the typical A-body, or your timing light is lying to you,or she is really really lean, or the stinking Vcan is interfering. Lol.
If you keep the 12 and 30 with no other changes, then IMO, the MSD will not change much if anything. Cramming timing at an engine solves nothing, Give her what she wants and no more. Just one degree into detonation will lose more power than 2,3 or even 4 not enough. Detonation is the engines enemy. But also IMO, 30 total is not enough power-timing.
The ECU has exactly two jobs; Job#1 is to receive the signal from the pick-up and modify it for Job #2, which is to trigger the coil to fire. It is nothing more than an interpreter and a glorified set of points. Well a bit more than nothing; there are no points to burn up and no rubbing block to wear off. If your car starts, runs, and revs to the proper shift-rpm, then it's doing it's job. I have run a 360hp 367 for several years on an old Orange box, and even now 20 years later, and 70hp more, I still have no need for a CDI MS system, altho I do run a different Amp.
IMO, your tune could just be a little better.
Click to expand...
Hmm well if I give her more timing it starts sounding like I have a vacuum leak or something, maybe I'm too lean at idle it's a 600 1406 stock settings
 
MoparMike1974 said:
If your rear has too much drag with 80w90, you need more horsepower. Then you wont notice or care :)
With the limited miles most of our cars will see it does not make sense to spend the extra money on synthetics.
Click to expand...
Hahhaha yeah I drive my cars every day switch off ever other week.
 
I run some 85w140 gear oil in mine, every manual trans I have changed to it shifted a lot smoother to
 
You must log in or register to reply here.
-

Back
Top