My goal is to get 25+ mpg from my 99 XJ with 30 x 9.5 R15 ATs - Page 35 - JeepForum.com
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Unread 08-22-2013, 02:11 PM   #511
Charley3
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Quote:
Originally Posted by bobthecatkiller View Post
http://jeep-xj.info/HowtoMAPsensor.htm
how about this you can manually lean out your a/f ratio
Interesting, but it says you can only fine tune mixture from 80 to 100% throttle. So sounds like more of a power tune than an economod, IMO.

From what I read, this is mostly done to fine tune strokers.

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Unread 08-22-2013, 02:42 PM   #512
Newtons3
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Im on my tiny phone, away from home, in the Republic of Texas. So bear with me, Im having trouble quoting. There are no cheap, easy to install lockout hub conversions. If all the Warn will handle is 31s, then it is weaker than the unit bearings and a downgrade. Not an option for me. At 30 PSI or better, it is almost impossible to vapor lock. The MAP mod has great affect on OBD-I vehicles. That and an adjustable fuel pressure regulator are a great way to adjust a/f ratio. On OBD-II vehicles, I am told, but have not confirmed, the MAP is only good for 5 percent of fuel trim....but Im thinking I might take that 5 percent. That small percent, a little from the IAT, a little from TPS, etc. After a while, we have quite a measurable change.
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Unread 08-22-2013, 06:12 PM   #513
longtro
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Quote:
Originally Posted by Charley3 View Post
I'd love a 210F to 215F stat. Preferably a 210F or 212F
Would I need to upgrade my tranny cooler to something bigger than the stock tow package one? Probably so, if using 215F stat. What size tranny cooler would be appropriate?
Hey there... I know I am realy late to this party and have just started trying to read the thread..

MY stock tow package trany cooler is actually a heat exchanger in the rad.. there is a huge cooler infront I thought was for the trany but it is a/c : ( I plan to loose the ac cooler and put a large trany cooler in the front.

so it may have already been explained but make sure you have a trany cooler and not a heat exchanger(fooled by the a/c like me.)
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Unread 08-22-2013, 08:34 PM   #514
ninjakid
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Oil heat interchanger partially installed.
Its a pain.
Forgot to take a picture of it mocked up in place.
The original fitting needs a 1" wrench.
The vw nut is somewhere in the 27mm range and I've yet to find anything that fits perfectly.
The vw nipple is slightly too short.
If you thread the nipple in fully it doesn't even stick out the heat interchanger.
Currently trying to figure out how far I need to thread in the nipple to ensure the filter has enough to thread onto and the nipple itself has enough threaded into the 90* adaptor so it doesn't leak.
If you use a propane torch to heat up the adapter for a couple minutes you can screw it in by hand which is very helpful when you have to redo it several times.
But yeah I can now completely confirm that the oil heat exchanger hesco sells is a vw one you can get far cheaper elsewhere.
Its just a pain to get setup.
And changing the filter will be slightly harder since its next to the evap canister.
1377224525047.jpg   1377224564563.jpg  
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Unread 08-22-2013, 09:08 PM   #515
Charley3
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Quote:
Originally Posted by Newtons3 View Post
Im on my tiny phone, away from home, in the Republic of Texas. So bear with me, Im having trouble quoting. There are no cheap, easy to install lockout hub conversions. If all the Warn will handle is 31s, then it is weaker than the unit bearings and a downgrade. Not an option for me. At 30 PSI or better, it is almost impossible to vapor lock. The MAP mod has great affect on OBD-I vehicles. That and an adjustable fuel pressure regulator are a great way to adjust a/f ratio. On OBD-II vehicles, I am told, but have not confirmed, the MAP is only good for 5 percent of fuel trim....but Im thinking I might take that 5 percent. That small percent, a little from the IAT, a little from TPS, etc. After a while, we have quite a measurable change.
You have good info, as always. Thanks.
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Unread 08-22-2013, 09:21 PM   #516
Charley3
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Quote:
Originally Posted by longtro View Post
Hey there... I know I am realy late to this party and have just started trying to read the thread..

MY stock tow package trany cooler is actually a heat exchanger in the rad.. there is a huge cooler infront I thought was for the trany but it is a/c : ( I plan to loose the ac cooler and put a large trany cooler in the front.

so it may have already been explained but make sure you have a trany cooler and not a heat exchanger(fooled by the a/c like me.)
I know more now.

In theory a 215F stat would be really efficient, and probably would be if engine and transmission were designed for it.

However, I have since concluded that a 205F stat is best. It runs from 208F to 212F, usually 210F. That is perfect for the 4L Jeep engine, IME.

A 205F Gates or ACDelco stat is perfect for people in a moderate to cold climate IMO. I'm inclined to say Gates for moderate climates, and ACDelco for cold climates. That is because I suspect the ACDelco is slightly warmer than the Gates.

For the auto transmission, I don't think an auxiliary cooler is necessary, but it is nice to have. My current Jeep has an auxilliary cooler. My prior two Jeeps had none. All 3 had 205F stats. No problems with any Jeeps.

What I do think is necessary, or at least a really good idea, is synthetic motor oil and transmission oil. I really like Mobil One 0-40 motor oil, and Mobil One transmission oil.

If you want to take the protection step further, add a dedicated transmission cooler.
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Unread 08-25-2013, 09:31 AM   #517
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Is it possible to list recommended items for fuel economy at the front of this thread? Example would be fuel injector upgrade, thermostat upgrade, synthetic oils, spark plugs and etc.
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Unread 08-25-2013, 02:49 PM   #518
Charley3
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Is it possible to list recommended items for fuel economy at the front of this thread? Example would be fuel injector upgrade, thermostat upgrade, synthetic oils, spark plugs and etc.
All the basic mods, the places to start, are listed in the OP.

I've been updating the OP.

For spark plugs, stock plugs are best. Whatever is stock for your model year.
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Unread 08-25-2013, 03:05 PM   #519
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Its installed.
Changing the oil filter will be a challenge.
Tied it into the return line since the heat interchanger is 5/8th, the return hose is 5/8th and the line from the thermostat housing is 11/16 which is impossible to find and the current hose is too short
Heat interchanger gets very warm very quickly.
Will see what happens.
1377464411910.jpg   1377464434040.jpg  
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Unread 08-25-2013, 03:47 PM   #520
Charley3
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Quote:
Originally Posted by ninjakid View Post
Its installed.
Changing the oil filter will be a challenge.
Tied it into the return line since the heat interchanger is 5/8th, the return hose is 5/8th and the line from the thermostat housing is 11/16 which is impossible to find and the current hose is too short
Heat interchanger gets very warm very quickly.
Will see what happens.
Lets us know how it affects gas mileage. I expect it'll make most difference in Winter by helping you run full op temp, instead of underheating.

I look forward to hearing about your results, especially next Winter.
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Unread 08-25-2013, 03:49 PM   #521
Charley3
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I just updated the OP (again) to help new comers to the thread be able to get more info in one place.
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Unread 08-25-2013, 04:08 PM   #522
Newtons3
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Originally Posted by Charley3 View Post
For spark plugs, stock plugs are best. Whatever is stock for your model year.
This is where we disagree. I don't think this blanket statement is true for everyone. I believe that the Iridium plugs are at least as good (I believe better) as the factory plugs. I believe those of us with other modifications may also be facing a heat range conundrum. I don't feel like this has been explored sufficiently to put it to rest. I do believe it will be....shortly.
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Unread 08-25-2013, 04:10 PM   #523
Newtons3
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Quote:
Originally Posted by Charley3 View Post
Lets us know how it affects gas mileage. I expect it'll make most difference in Winter by helping you run full op temp, instead of underheating.

I look forward to hearing about your results, especially next Winter.
I am hoping to get one of my test mules up and running and test the same concept on the fuel line.
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Unread 08-25-2013, 11:27 PM   #524
Charley3
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Originally Posted by Newtons3 View Post
I am hoping to get one of my test mules up and running and test the same concept on the fuel line.
That's really interesting. I wonder how much it might help? I could see this potentially offering benefits in a cold climate, but you live in a hot climate. Isn't your fuel already plenty warm?
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Unread 08-26-2013, 08:47 AM   #525
Newtons3
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I am thinking I'd like to try the fuel at around 200 degrees. I can't put my finger on a definite reason for that number, but that's where I'm wanting to start. I know others who have done this have used temps in the 230-260 range. I'm not sure I'm ready to start that high.
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