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-   -   How does the SRT become faster with time ? (http://www.jeepgarage.org/f97/how-does-the-srt-become-faster-with-time-72116.html)

DarkHue 02-25-2014 12:56 AM

How does the SRT become faster with time ?
 
I've been told that the longer the differential breaks in, the faster the car gets. As in an SRT with 2000km performs a bit slower than one with 15000km.

I would like to understand the technical details behind this phenomenon. Does anyone know how and why does this exactly happen ?

greenwayer 02-25-2014 01:15 AM

Re: How does the SRT become faster with time ?
 
Quote:

Originally Posted by DarkHue (Post 981817)
I've been told that the longer the differential breaks in, the faster the car gets. As in an SRT with 2000km performs a bit slower than one with 15000km.

I would like to understand the technical details behind this phenomenon. Does anyone know how and why does this exactly happen ?

I doubt there is a break in for the diff past 100 kms in which the fluid circulates, however the piston rings set in the engine over a few thousand kms which provides better compression.

Strongjeff 02-25-2014 01:31 AM

Re: How does the SRT become faster with time ?
 
Quote:

Originally Posted by greenwayer (Post 981828)
I doubt there is a break in for the diff past 100 kms in which the fluid circulates, however the piston rings set in the engine over a few thousand kms which provides better compression.

More or less, its really that the engine loosens up and does not have as much drag on th3 rotating assembly. It not just the srt but all cars get faster over time before engine wear begins to slow them back down. Ex. A 3.6 camaro gets faster until about 35000 miles before it slows down. Its actually slower at 50k miles then they are new. My 3.7 is still getting faster at 68k.

YjagetaJeep 02-25-2014 02:18 AM

Yeah, When you think about all the rotating and sliding parts of an engine, they akl come from the factory freshky milled , ground, etc and put together pretty tight. As the engine "breaks in" all those parts...the shaft, cams, rods, pistons, valves, timing gears, etc all start to wear down just a tiny bit and start to fit each other better. It's a thing of beauty for a motorhead!
Another part that "breaks in" is a subwoofer! As you use it the rubber surround loosens up and the cone moves more freely, giving you the deeper bass notes. Good stereo shops will tell you to take it easy on the gain of a newly installed sub to give it a chance to break in.

Strongjeff 02-25-2014 03:22 AM

Re: How does the SRT become faster with time ?
 
Quote:

Originally Posted by YjagetaJeep (Post 981852)
Yeah, When you think about all the rotating and sliding parts of an engine, they akl come from the factory freshky milled , ground, etc and put together pretty tight. As the engine "breaks in" all those parts...the shaft, cams, rods, pistons, valves, timing gears, etc all start to wear down just a tiny bit and start to fit each other better. It's a thing of beauty for a motorhead!
Another part that "breaks in" is a subwoofer! As you use it the rubber surround loosens up and the cone moves more freely, giving you the deeper bass notes. Good stereo shops will tell you to take it easy on the gain of a newly installed sub to give it a chance to break in.

well said!

Scottina06 02-25-2014 11:13 AM

Re: How does the SRT become faster with time ?
 
not sure Id call it a phenomenon....but it does happen with these vehicles that I didn't really feel with other vehicles Ive had. Maybe a tad bit with other vehicles.....but not as much as with these beasts. Remember...Ive had two of these beasts.....a 2013 and 2014. The 14 seemed to come alive even more so than the 13. maybe its the tranny difference not sure. Some of the above is correct and parts wear in...but I doubt they wear much in a few thousand miles. I think a lot has to do with factory tuning and this thing learning your driving habits etc.

DarkHue 02-25-2014 01:13 PM

Re: How does the SRT become faster with time ?
 
Thank you for replying guys.

Quote:

Originally Posted by Scottina06 (Post 982032)
not sure Id call it a phenomenon....but it does happen with these vehicles that I didn't really feel with other vehicles Ive had. Maybe a tad bit with other vehicles.....but not as much as with these beasts. Remember...Ive had two of these beasts.....a 2013 and 2014. The 14 seemed to come alive even more so than the 13. maybe its the tranny difference not sure. Some of the above is correct and parts wear in...but I doubt they wear much in a few thousand miles. I think a lot has to do with factory tuning and this thing learning your driving habits etc.

Thank you for your input. So it seems like software can also contribute to the increased speeds as time goes by ? Does this adaptive system keep collecting data infinitely ? (which I assume it should for maximum efficiency).

I'm 2500km in and I do notice some mild difference compared to 1000km, especially the break in period <1000km. For example, I get consistent <4.8 seconds whereas I used to get 4.9+ before 2500km.

This is the reason I'm very interested to know more about this, because I can also feel the difference ! Anybody else notice this too ?

14StormTrooper 02-25-2014 03:05 PM

I'm at 19k miles and mine is extremely quicker than a few months ago.

jbjones85 02-25-2014 03:55 PM

Quote:

Originally Posted by tchrist30 (Post 982165)
I'm at 19k miles and mine is extremely quicker than a few months ago.

Nice. How's she holding up over time? I've had mine since November and am at 9k

mrmaker 02-25-2014 07:14 PM

Re: How does the SRT become faster with time ?
 
Quote:

Originally Posted by tchrist30 (Post 982165)
I'm at 19k miles and mine is extremely quicker than a few months ago.

That's because your on the gas Tom:D. In all seriousness, I'm on 7700ks and the beast is feeling super strong and pulling through the cogs harder then ever.


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