So anyhow, I have a CC 68-231-4 coming my way today. I did more searching and reading last night and now I'm waffling on the CC. It seems as though the Lunati 63500 might be a better choice?
My rebuild is consisting of the following;
- 4.2 12wt crank .010/.010
- 4.2 rods
- NVH block from a 99XJ, .030 but otherwise untouched
- H825CP-030 pistons, stock @ 15.8cc
- Perfect Circle 40514CP030 moly rings
- 99+ intake, currently a stock TB. I'll probably go to a 62 or 63mm from Leigh once I get it broken in. I'll probably machine a 1" TB spacer for it as well, maybe for nothing more than just to play with the mill.
- Stock injectors*
- New Clevite mains
- New Clevite rods (some of the mains and rod bearings were gouged, assuming from bits of the cam getting in)
- Old Clevite cams from 2009 (no damage, babbit is all still beautiful)
- New Victor Reinz gaskets all around
- Melling M-81A standard oil pump. Reusing from the 2009 build, I opened it up to check for damage, none found, will reassemble when I can find a thrust plate gasket for it.
- PureOne PL-30001 filters
- Brad Penn (2 cycles of break-in, then 10W30). I'll probably run CompCam EOS on top of that. Still no issues with the now ~150k mile catalytic, even after running Brad Penn for the last 15k.
- Cloyes C-3053 "link" non-roller type timing set**
- Stock pushrods
- Stock rockers
- Crower Cam Saver lifters
- Mopar Performance P5249464 springs (0.400 / 0.525)
- Mopar Performance P4452032 retainers
- Mopar Performance P4452030 locks
- Stant "Super" 195 t-stat
- OEM water pump from 2009
- New Felpro headbolts
- eBay OEM-style radiator
- Taurus electric fan
- New reman distributor (after hearing stories of chewed up cam gears, I thought it better to start with fresh)
- New AC Delco "stock" 7mm wires
- Champion RC9YC's or NGK ZFR6F-11's. I have both, haven't decided which ones it will get for initial start.
- Stock coil
- "Accordion" style cheap header. Other than a very minor crack that I stop-drilled and welded, it's holding up far better than the OEM garbage
TJ is sitting on 35x12.5's wrapped around alloys, ~4.5" of suspension, 1" of body, 1" motor mount lift, NV3550, 4.11's, 8.8 in the rear, alloy'ed LP 30 in the front (building a HP30 for it), super short SYE, blah blah blah. Driving style is heavily varied. I drive "spirited" around town, I do a ton of ~75mph highway driving and fairly often pull a ~2000-3000lb trailer. Off road I'm pretty mild on it, I'll take it to the redline if I'm trying cleaning the tires out or if I'm having a bitch of a time getting up a waterfall.
So, first things first;
* Yes, I'm aware that with my past build (mostly the same, stock cam, OEM engine driven fan), from everything that I've read, I should be in ping city. Stock injectors, high SCR, high DCR. According to the calculator, SCR is 9.8, DCR is 8.47, quench is 0.0645 with the stock cam that I was running. Initially I ran it on 93 due to my fear of the DCR. It never once pinged, so I ran that tank dry and went to 91, never pinged. Dropped it to 87. Even in mid July heat, pulling the trailer, AC on the entire way, cruising 70+mph across I-70, I never heard or felt any ping or detonation. Why? I have no idea. Stock injectors, no MAP mod, stock IAT location. With the CC 68-231-4, DCR goes to 8.57, a 0.10 increase over the OEM cam. Will this cause me problems? I don't know. The Lunati 63500 puts the DCR at 8.52, right in between stock and OEM. I don't think I'm overly concerned with pinging or detonation right now. I was ok with 87, so even with the increase of DCR, I think going to 91 or 93 will fix that. If I need to go to a Ford 24# injector, I will. I'm also planning on moving the IAT and getting a Leigh MAP modifier (if he doesn't have any, I'll build my own). I'll also drop the t-stat to 180 if need be.
** The stock style, "link" timing chain, P\N C-3053. All I see everywhere is that you need to run the dual roller JP or Cloyes chain. Why? My (albeit stock) 4.0L went 130k on the OEM chain before the skirt on #5 broke, sending the rod through the block. The Cloyes stock chain that I just pulled off of this motor, 15k miles of wear on it, was still tight (though not reusable as it's the 4.0L set). I'm not arguing that you shouldn't run the dual roller, but is the only reason that everyone recommends it is because that's what the performance guys do? I have only seen one stock timing chain failure on this site and the pictures show it was clearly due to a lack of lubrication. I did just notice that Cloyes makes a single roller chain, P\N C-3062, which interestingly is 25% cheaper than the non-roller I already bought. Is that going to be any better or worse than the non-roller chain? Both the non roller and the single roller have no options for advance or retard, they have to be installed straight up. The dual roller 9-3127 allow for -4, 0 and +4, but I have a feeling that will be to much either way, so again, straight up. The JP chain is nice, multiple timing options. And it's all billet, but that goes back to, I've only ever seen one chain fail on these boards and I believe any of the 4 chain options would have failed under those circumstances. I just have a hard time coughing up another $100 for something that works the same way the $100 cheaper version does. Thoughts?
Lastly, the cam. The original build back in 09 was set to run the 68-231-4. Due to a failure of research on my part and a time crunch, I didn't and slid the stock cam back in. A week or so ago, I called Comp, they recommended the 68-232-4. I posted about it, the 68-231-4 was again recommended by you guys. I have more faith in your opinions than that of Comp's to be honest. But then I do what I probably shouldn't and I search some more. Then I see Dino and a few others recommend the Lunati Voodoo 63500 over the 68-231-4. Hmm. Now, my problem is, I understand what a cam does and sort of how it works. What I don't understand is lobe separation, ATDC, BTDC, etc. The Lunati seems to be favored due to it's less aggressive ramp (which I do understand), not as noisy, not as much wear on the valve seats. The only bad thing seems to be that the journals are junk on the Lunati's and need to be polished. Shouldn't be overly expensive at my machine shop. So at this point, I think I'm going to order the Lunati from Summit, unless anyone has any thoughts on why I shouldn't.
I could have sworn I read it here (but unfortunately can't search, since the forum refuses to search "68-231-4"), but can you use stock springs on the 231-4 or the 63500? As I said, I could have sworn I read it was doable, but then again, I've also read that the springs will bind at that lift (.484 in the case of the Lunati). I already have the MP springs, retainers and (soon) locks, but I'm also trying to do what I can to reduce the chances of wiping out another cam. Reducing the seat pressures would seem to help that. In this past build, I believe it was a lifter failure that cause the cam lobe to wipe, but I'll never know that for sure.
So, that's it, hopefully for questions before final assembly. I'll start a new thread once I get it assembled to update progress on things.
If it seems like it's wearing unusually bad or stretching, then I'll put a double roller on. With the electric fan setup, I can have the rad and fan out in 10 minutes, making a little more room to get to the timing cover.
