Any interest here in better mpg mods?
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As i understand i should be looking for an aftermarket TB of 70mm because this one will gain the most ?
There are some improvements over the years on the oem ones, like mine the 2000 has the smal TB on it, so i'll have too look for a later year TB of a 4.7L or get a aftermarket 70mm TB.
There are some improvements over the years on the oem ones, like mine the 2000 has the smal TB on it, so i'll have too look for a later year TB of a 4.7L or get a aftermarket 70mm TB.
I am currently getting 16.3~16.5 mpg's on the 200ish mile tanks to & from work. I suspect the degraded cam & crank sensors were artificially advancing timing which is why I got the 17.0 mpg tank after the MAP sensor swap. I dont have high hopes for any mpg change from just the TB alone, this mainly comes from the JTCM mod bust (I suspect 3.92 geared trucks benefit from this the most, there is just not enough torque at 1400~1800 rpms to take advantage of it with the 3.55's I have and the taller tire). I could always just drive faster lol, but that starts to take an aero hit with the higher speeds.
I want to go back to the DTCM but will now have to wait a bit since I'm going to do the TB install next. What would be nice is to find a way to get the JTCM to go into 4th easier and hold it. I have seen it do it but have not wrapped my head around why it is doing it. Throttle input seems to be the key and the 1st thought is to offset the TPS sensor voltage a bit but, who knows what can of worms that would open for other aspects of the engine performance.
On the airaid intake tube that does not fit, I checked it against the 70mm TB and it is the same issue. Going to buy a silicone reducer and a different hump hose to the air box and get it installed down the road. Would have been nice to see what the difference was in the oem setup.
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I'm going to wait and see what the 70mm TB does on yours, but i'm going to see what this one will cost me, i think i can find a 2001 and up TB over here, because there are some Grand Cherokee's and Rams with the 4.7L in the junkyards, the 2001 was 68mm if i'm not mistaken so this would be an big step up on mine.
About the JTCM, like i said before it all depends, i'm doing 1600rpms at 60mph and it nevers comes out of OD, i can let it slow down to 55mph, but when i want to overtake at that speed it shifts down, with 60mph it's stays in OD, so for me it's perfect this way.
I don't know wich gear you mean by 4th, but you can push the OD button and it shift down, sometimes when towing i use the OD off function.
But when you have to use it you are probably back on the same rpm's as with the DTCM....
Changing the voltage of the TPS to the PCM could be doen with a simple resistor, but i don't know either what else is infected by it, think you would only have problems on idle, but might be a solution and easy to realize and change back if other problems occure.
With the right reducer the Airraid should be fairly easy to mount, i'm very interested how it will run after, cause mine was on the truck when i bought it, so i have no reference.
Good luck and i'll patiently wait for the results.
About the JTCM, like i said before it all depends, i'm doing 1600rpms at 60mph and it nevers comes out of OD, i can let it slow down to 55mph, but when i want to overtake at that speed it shifts down, with 60mph it's stays in OD, so for me it's perfect this way.
I don't know wich gear you mean by 4th, but you can push the OD button and it shift down, sometimes when towing i use the OD off function.
But when you have to use it you are probably back on the same rpm's as with the DTCM....
Changing the voltage of the TPS to the PCM could be doen with a simple resistor, but i don't know either what else is infected by it, think you would only have problems on idle, but might be a solution and easy to realize and change back if other problems occure.
With the right reducer the Airraid should be fairly easy to mount, i'm very interested how it will run after, cause mine was on the truck when i bought it, so i have no reference.
Good luck and i'll patiently wait for the results.
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Joined: Apr 2010
Posts: 87,453
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From: Clayton MI
I'm going to wait and see what the 70mm TB does on yours, but i'm going to see what this one will cost me, i think i can find a 2001 and up TB over here, because there are some Grand Cherokee's and Rams with the 4.7L in the junkyards, the 2001 was 68mm if i'm not mistaken so this would be an big step up on mine.
About the JTCM, like i said before it all depends, i'm doing 1600rpms at 60mph and it nevers comes out of OD, i can let it slow down to 55mph, but when i want to overtake at that speed it shifts down, with 60mph it's stays in OD, so for me it's perfect this way.
I don't know wich gear you mean by 4th, but you can push the OD button and it shift down, sometimes when towing i use the OD off function.
But when you have to use it you are probably back on the same rpm's as with the DTCM....
Changing the voltage of the TPS to the PCM could be doen with a simple resistor, but i don't know either what else is infected by it, think you would only have problems on idle, but might be a solution and easy to realize and change back if other problems occure.
With the right reducer the Airraid should be fairly easy to mount, i'm very interested how it will run after, cause mine was on the truck when i bought it, so i have no reference.
Good luck and i'll patiently wait for the results.
About the JTCM, like i said before it all depends, i'm doing 1600rpms at 60mph and it nevers comes out of OD, i can let it slow down to 55mph, but when i want to overtake at that speed it shifts down, with 60mph it's stays in OD, so for me it's perfect this way.
I don't know wich gear you mean by 4th, but you can push the OD button and it shift down, sometimes when towing i use the OD off function.
But when you have to use it you are probably back on the same rpm's as with the DTCM....
Changing the voltage of the TPS to the PCM could be doen with a simple resistor, but i don't know either what else is infected by it, think you would only have problems on idle, but might be a solution and easy to realize and change back if other problems occure.
With the right reducer the Airraid should be fairly easy to mount, i'm very interested how it will run after, cause mine was on the truck when i bought it, so i have no reference.
Good luck and i'll patiently wait for the results.
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From: Clayton MI
So much for that thought.......
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The pin IO was the first thing I looked up when I found the manual. Also had some thoughts of finding a way to lock out the 2nd OD via switch.
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Is this 1st hand experience with HPT?
RS brake caliper siezed... picked up another cheapie with the expectation to swap over to the better brake setup. Got it fixed but decided to try something I'd thought of after doing the last one. With the banjo bolt removed, I sprayed the inside of the caliper real good with brake cleaner, drained it out and found some gunk coming out. So I found a syringe I have and dropped in some ATF in there and let it soak overnight. Dumped it out the next morning and the color did change some but nothing drastic. Did not really see anything at first glance. Flushed out the bore again with brake clean, compressed the piston and motored on. When cleaning up, then I took a closer look and found debris in the fluid. Kinda surprised I found anything but there it was. Once back on the road, no brake issues once again. I may go pull that other caliper off and repeat that on it as well.
Throttle body goes in this morning, have a 80~90ish drive today to visit daughter & grand kids, will report back with impressions. From what I read, bottom end torque will drop initially until the adaptation is done. Will disconnect the battery to speed things along.