Ive decided to take the plunge and go for the 4.0 EFI head upgrade on my eagle. I have seen the conversion done but it was on a manual. My biggest concern is weather the stock automatic in my 83 eagle...rebuilt of course...will be able to tolerate the extra horses being pushed through it...Id love to put a later model tranny in it but Im not sure just how much work and fabrication that might involve.
i'm pretty sure it can handle it. my dad said he had one in a dodge dart with a high powered V8. so a strait six with a few more horses shouldn't hurt it any. in fact there are a few members here that have done the upgrade with the stock auto still in there cars.
I'm in the same boat with you Sanebo. I have been trying to wrap my head around a 4.0 conversion for some time now. So far all I've come up with is questions. :banghead: Having a spare engine means I don't have to rush. I just want to make sure all my ducks are in a row before I purchase a 4.0 head. The eagle is an 83 SX4 with a three speed auto. What I have so far on the wish list is as follows: New head, headers, clifford intake, and a weber carb.
Some questions for anyone who knows.
1) What are the proper rocker preload specs?
2) What push rods will I be using? 4.2 or 4.0
3) Are there any major (or minor) changes that will need to be made to the engine block or engine components to ensure a proper balance with the 4.0 head?
4) Are there any engine rebuild spec changes that I should be aware of as of a 4.0 head swap?
Sorry all. That was more then a few questions.
Best,
Will
Shanebo your the stock transmission is plenty strong enough as long as it is in good shape. It is basically a Torqueflite 904 that was put behind many V8's. I did a 4.0 head swap and cam but with a carb and have a lot more HP and besides the torque converter snout coming apart, which happens on stock eagles. the transmission works great. I would suggest a Transgo shift kit to everybody to get better shifts and it will help your clutches last longer. When the transmission rebuilder took mine apart he said with the exception of the torque converter coming apart and destroying the pump, the rest of the transmission was in great shape and it wouldn't have needed a rebuild for quite some time and no evidence of it being rebuilt with 165k miles on it.
I have also heard that you can put 904 internals in the stock transmisson, I am going to do this with one of my spares when time allows
998 is an upgrade froma 904. A 727 is top of the 3
Quote from: mudkicker715 on March 20, 2011, 10:22:43 AM
998 is an upgrade froma 904. A 727 is top of the 3
Correct. The seldom seen 999 is a bit beefier 998. I believe only found in Jeeps.
Chrysler used the 42RE in the Grand Cherokee's behind the 4.0 I6. From what I have read the 42RE is basically a 998 with an added electronically shifted 4th gear.
Quote from: IowaEagle on March 20, 2011, 10:41:39 AM
Quote from: mudkicker715 on March 20, 2011, 10:22:43 AM
998 is an upgrade froma 904. A 727 is top of the 3
Correct. The seldom seen 999 is a bit beefier 998. I believe only found in Jeeps.
When I had my transmission rebuilt, the rebuilder built it to 99 specs. Larger drum and one more clutch plate.
Sweet..this answers my question....The tranny in the car is fried and going to need rebuilt...I just didnt want to pay all that money getting it rebuilt and then blow it apart right off the get go.
By the way Will you will want to use a 4.0 cam, and push rods not sure of the rocker preload specs though...Tougeagle would be the one to ask on that one...hes the one I got all my info from...plus hes done it already...hes a very knowledgable fellow!! ;D
Here's the most comprehensive head swap article: http://www.monsterslayer.com/pages/jeep/40Head/40Head.htm
Quote from: eaglefreek on March 21, 2011, 09:50:48 AM
Here's the most comprehensive head swap article: http://www.monsterslayer.com/pages/jeep/40Head/40Head.htm
HI thank you for this site it is very informative .I am going to save this one.........Don
Very good site!!