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I would second the 4.0 option, there is not that much power difference.
Is the 4.0 a straight forward swap....Im seeing quite a few of those in the price range Im looking for. My truck is non sai and most 4.0 long blocks seem to come this way so it would be a good option,
The difference between the 4.0 and 4.6 is the Crankshaft. I believe the issue with the 4.6’s in the ‘03’s and ‘04’s was poor castings, at least that is one. So a RR earlier casting would fix the issue, I don’t believe it is because of the crankshaft.
But with the 4.0 out you could put in better camshafts and have more peace of mind I suppose. Even the 4.6 is a little underpowered for a 5000 pound vehicle so I wouldn’t go 4.0, but that’s just me.
If you can do it port match the exhaust port of the Head, and the Exhaust manifold. I ported and polished mine, and that was the restrictive area. The intake side of the head really did not need much removed.
I have a 1996 vintage P38 4.0L running in my '03 Disco II with a swapped CPS mount (to support Bosch) and an OEM 4.6 camshaft. I rebuilt my 4.6L SAI heads and installed them on the 4.0L block for emissions compatibility with my truck. Runs like a bear with no noticeable seat-of-the-pants power difference whatsoever. The block castings of the 4.0L and the 4.6L are IDENTICAL, only the accessories and sensors change depending on whether you have GEMS, Bosch or SAI.
The difference between the 4.0 and 4.6 is the Crankshaft. I believe the issue with the 4.6’s in the ‘03’s and ‘04’s was poor castings, at least that is one. So a RR earlier casting would fix the issue, I don’t believe it is because of the crankshaft.
But with the 4.0 out you could put in better camshafts and have more peace of mind I suppose. Even the 4.6 is a little underpowered for a 5000 pound vehicle so I wouldn’t go 4.0, but that’s just me.
If you can do it port match the exhaust port of the Head, and the Exhaust manifold. I ported and polished mine, and that was the restrictive area. The intake side of the head really did not need much removed.
I'll bet you $20 all that work didn't make two tenths of a second difference on your 0 to 60 time. get an app and do the test and I'll post up results from my 4L discos with 220,000 miles
I'll bet you $20 all that work didn't make two tenths of a second difference on your 0 to 60 time. get an app and do the test and I'll post up results from my 4L discos with 220,000 miles
Maybe, maybe not, but with my Kent Cam it is noticeably better passing at highway speed. With a stock cam would it matter? Maybe not, because it is already breathing as much as it can.
I hope it made a huge difference, because if it did I would do it also. But I doubt it did and I am not going to invest the time without some data. Let me know if you want the $20
I hope it made a huge difference, because if it did I would do it also. But I doubt it did and I am not going to invest the time without some data. Let me know if you want the $20
I’m happy with it, and that is good enough for me. If I get around to a 0-60 time I will post it. But it also has an upgraded Cam, so that has to be taken into account.
After getting my D2 running perfectly something in the engine let go while going 75 on the interstate. No warning at all. Anyway it knocked the bottom out of the oil pan and took out a chuck of the block. I need some options for a used motor. hoping to stay under $1000. Ill be doing the swap myself. Ill replace the head gaskets and oil pump before the install as well. on a side note the lady behind me stopped and said it looked like something you see in a nascar race......smoke and flames coming out the back. I posted the carnage for your viewing pleasure......
