Dakota Durango Forum banner

4.7 with 5.7 crank

5K views 6 replies 3 participants last post by  Dakota J 
#1 ·
So I just bought a hemi 5.7 to rebuild and put in my 02 Durango. Just pulled the 4.7 out and tore down the 5.7. I've been looking at stroking the 5.7 to a 392. Then I had a crazy idea of would the 5.7 crank work in the 4.7? You can use 6.00 or 6.125 rods and choose your Pistons. But would the crank actually fit. I've searched but to no avail. Anyone try this? Stock stroke is 3.405 from what I've read and the hemi is 3.58. Not a huge difference. Can still have a good 1.6-1.7 rod to stroke ratio and enough piston skirt sitting just below the 9.09 deck.
 
#2 · (Edited)
With a 3.58 crank. 6.125 Rod and 3.70 piston with a compression height of 1.190 you'll have a 5.1... I saw some one around here saying they had a custom stroked 5.0. Could this be how? The piston will sit 0.015 above the deck but a proper sized head gasket will take care of that. Run 10.5 compression you should be able to hit 300whp with some slightly ported/blended heads.
 
#3 ·
You are going to have to take a ton of measurements and if you are off too much, then it will not work.
Not many have tried to experiment with the 4.7 anymore since the HEMI swap is so much easier and is much better power starting platform than the 4.7.
 
#4 ·
Yea the only thing that has me down is all the wiring to swap it over. It's not my DD so I have time to play with it. I would hate to invest bank in the 4.7 for it to have issues. I was gonna pick up a forged ho motor with bad main bearing for $200 but decided on the hemi swap instead.
 
#5 ·
The wiring is so much easier now than when I first joined here. Before, you had to have the 4.7 and 5.7 wiring harnesses so you could splice or repin the connectors to run the HEMI in the Dakota's and 1st Gen Durango's. Now, Hotwire Auto and Painless Wiring Systems offer a Dakota HEMI swap harness work. They will require your harness but if is not a DD like yours, then it is good time saver for sure. Plus, you will save a lot of money for a new harness, which for these trucks, Chrysler isn't making some parts for anymore, which could include the engine wiring harness.
 
#6 ·
Yes i hit up Hotwire and they wanted $1600 to modify my harness to work. For someone that wants plug and play its not too bad. I bought a like new harness for $100 for the hemi. I made a spreadsheet from a combination of other guys that have documented this engine swap showing what wires are what and what connections need to be made. I feel about 80% certain I have them all labeled. Once I start splicing will be the tell. From what I've read most go straight to the motor and a few got it the fuse box so chasing them down shouldn't be too hard.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top