A few things to share with everyone. I worked with Summit Racing and got a great deal on a Complete rebuild kit and the Comp Cams K kit 68-232-4 which inclides the timing chain springs lifters and all that great stuff. They were awesome letting me replace a few items in the kit and only making me pay the difference on the parts. I personally replaced the pistons in the kit with the 802's and went with the moly rings to match the 802's which are being sent out to get dished. I also replaced the oil pump with the mopar performance oil pump.
I had a few questions still.
1. Is the 4.2 liter oil pan bigger than the stock 4.0 pan?
2. On a 0630 head do I need to have it machined to fit Comp Cams springs or can I use them withour having to have the head worked for them?
3. The crank I scored is out of a 87 wrangler 4.2 with the 54mm nose. Do I need to do anything to this crank after the engin is put back together to make it fit with the rest of the accessories? Or is it the same exact length as the 4.0 crank?
Don't buy the comp K kit. The springs reainers and valve springs will not work on the 4.0 valves. The 258 and 4.0 have different size valve stems. The 258 stems are larger in diameter.
Could the head be machined to fit the springs? I am not so worried about the retainers and such since my machine shop stocks most of that stuff in bulk.
MarineJRM wrote:Could the head be machined to fit the springs? I am not so worried about the retainers and such since my machine shop stocks most of that stuff in bulk.
I haven't found any afermarket retainer that will fit the stock Jeep 4.0 8mm valves, 8 degree locks and comp springs. I'm not saying that there isn't one out there. If you find something out please let us know.
MarineJRM wrote:Could the head be machined to fit the springs? I am not so worried about the retainers and such since my machine shop stocks most of that stuff in bulk.
Yes the head can be machined. There is a fair amount of room under the spring seats.
Excellent it is well worth it in my opinion to run the springs that are supposed to be with the cam. It is just one of those things that when you measure the cost vs. peace of mind. I dont want to get the thing together and have it eat my cam within 5k.
Just make sure your machine shop can get the right retainers for the valves before they start cutting the head. If they find a retainer that works, can you please get a part number and post them on here.
Bodo wrote:yes, if you can find a retainer that works with our valves let us know!
I've been looking for the last month!
the "new" hemi retainers work with the stock 8mm 8* locks. they shorten the install height 0.040 - 0.050", BUT, they also let you run any of the "beehive" springs that have been released for the small block motors....
I don't think the Hemi retainers will work on the comp springs. I think someone posted the diameter of the Hemi springs(can't find it). But if I do recall the Hemi retainers were to small. Unless you want to change your stock Jeep valves to 1.94/1.50 Chevy valves, you are limited to what springs you can use. The Mopar Performance spring P5249464 with retainer P4452032, is the only drop in spring that I know of. Anything else is going to to take machine work. Personally I don't like the spring that Comp reccomends to use with that cam. The seat pressure is too low and spring rate is too high. With the more aggressive or faster cam ramps, I would like to see a higher seat pressure to control valve bounce. A lower spring rate should help with cam wear issues. The Moapr Preformance Springs advertise something around 120# installed at 1.64 and 270# spring rate.(Can't remember exactly), and are good for .525 lift.
The beehive springs are a great alternative to high spring rates. They can control the valve without high spring rates, do to there design. But it is going to take some research and machine work to get them to work on 4.0 head. I don't belive there is an inexpensive way around this issue, until an aftermarket company makes a spring and retainer for the Jeep application.
Well it certainly does look like I might need to invest in the Mopar springs if this is the case. I will take a look at the hemi retainers for the hell of it also just to satisfy my own curiosity. But if the mopar springs are the only drop in springs it may just be easier to go with them.
The cheapest place I found to buy the MP springs is http://shop.oreillyauto.com . Type in the mopar performance numbers in the search. Springs are $6.99 and retainers $4.99 each. You can also use this web page to do a price match with summit or Jegs. Be prepared to give them the web site and the process of how you got the price.
I worked with Summit Racing and got a great deal on a Complete rebuild kit and the Comp Cams K kit 68-232-4 which inclides the timing chain springs lifters and all that great stuff. They were awesome letting me replace a few items in the kit and only making me pay the difference on the parts. I personally replaced the pistons in the kit with the 802's and went with the moly rings to match the 802's which are being sent out to get dished. I also replaced the oil pump with the mopar performance oil pump. 
