Does your 4.0 stroker run like crap when cold? - Page 2 - JeepForum.com
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Unread 06-12-2013, 11:44 AM   #16
jsawduste
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2006 YJ Wrangler 
 
Join Date: Jul 2006
Posts: 2,959
Quote:
Originally Posted by 95yj0645 View Post
I will post my results tonight if I can find a small enough bit here at the shop.
Be looking for it. Don`t forget to let the ECM learn the change.

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Unread 06-12-2013, 04:25 PM   #17
95yj0645
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1995 YJ Wrangler 
 
Join Date: May 2010
Location: indiana
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Jsawduste you are right on the money with the .109 bit .. Runs much smoother at idle .. At least when it's hot I'm anxious to see how it does cold tomorrow morning
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Unread 06-12-2013, 05:09 PM   #18
jsawduste
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Quote:
Originally Posted by 95yj0645 View Post
Jsawduste you are right on the money with the .109 bit .. Runs much smoother at idle .. At least when it's hot I'm anxious to see how it does cold tomorrow morning
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Unread 06-12-2013, 05:26 PM   #19
95yj0645
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You can still tell its cammed but im idling right around 800 RPM. The true test will be tomorrow morning's cold start. One thing was verified though, it's running too rich.
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Unread 06-12-2013, 05:50 PM   #20
jsawduste
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2006 YJ Wrangler 
 
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Quote:
Originally Posted by 95yj0645 View Post
You can still tell its cammed but im idling right around 800 RPM. The true test will be tomorrow morning's cold start. One thing was verified though, it's running too rich.
Your cold start open loop will be better. I have no doubt.

The curse of OBD1 is the inability to change fuel mapping. The bleed hole helps at idle and low throttle openings. If you reduce FP it will run lean in open loop so it comes to a balancing act. Rather rich then lean though.

Here is another mod you can do which you will feel.


Moving the IAT from the hot manifold to the cold air tricks the ECM into adding more timing.

PCV setup.


Other end goes to the large port on the side of the intake back up to the rear elbow.

Another is modify the crank sensor to move it towards the passenger side. Take a bad sensor, cut the mount off it and join it to your good sensor. Sorry no pictures but you will figure it out.

My stroker likes timing, fuel and heat. More I give it the better it runs.

Hot lapping on the dyno proves the heat. Best runs were taken one right after another without a cool down.
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Unread 06-12-2013, 06:29 PM   #21
95yj0645
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1995 YJ Wrangler 
 
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Location: indiana
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Your engine paint and intake setup is almost identical to mine! Haha. My jeep Definately likes heat too. I like the idea for moving the IAT sensor, how much timing does it gain from this mod? Just a couple degrees advanced?
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Unread 06-12-2013, 08:35 PM   #22
jsawduste
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That is a good question. The answer is that it depends on the engine coolant temp and the incoming air temp. Not to mention the throttle position and road speed. Will say that it is a noticeable change. I still have the IAT in the intake and have enough wire to plug it into either sensor location.

Using my highly inaccurate stop watch and a GPS I saw an average of .3-.4 improvement in acceleration from various roll speeds. Seemed the greatest gains were at higher roll on speeds, say 60 to 80 whereas a 20-40 was at the lower end of the spectrum. But hell it is easy to do and it connected with JF`s most often used word.......cheap.

BTW, you have good taste in engine paint.
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