Pics of Engine Overhaul Begining!!

upnover said:
The crank and rods will not work to stroke it. That's what you change to stroke it. I would bore it only what it takes to clear the cylinders. No need to bore it more that what it takes, the gain is marginal. To do port work is costly, make sure who ever does it knows what you seek. More torque, not more horse power.
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Use the 4.2 crank and rods, w/ 4.0 pistons. I only bored mine .030 to avoid any cooling issues.
 
The gain is marginal. If it will clear up in .020 or .030 or .040 I'd go with that. For one, if you ever have to do it again, you can without much possible issue. The thiner the cylinder wall the more likely to have cooling issues. Keep in mind, I don't know what the wall thickness in a 4.0 . There may be no issue at all. I am just of the school of doing what needs to be done, and not more.
I'd concentrate on head work, and so on. The gains in head work, cam and lifters, and machine work, and quality parts will net you a lot more that going with a bigger bore than you need.
 
sounds good. i am doing this on a '88 renix, i have found a 91 HO head for cheap. will it bolt up to mine and will the camshaft be the same?
 
Hammerite_05 said:
sounds good. i am doing this on a '88 renix, i have found a 91 HO head for cheap. will it bolt up to mine and will the camshaft be the same?
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The '91-'95 heads are the best flowing heads for a 4.0, I'd use them if you can. Not sure about the sensor and wiring differences in the renix and the HO.
 
Like the others have said, the 4.2 crank and rods attached to 4.0 pistons, in the 4.0 block. I bored mine .030" over because it needed it. There is really no need to bore it out unless you have to, most of the power is gained by the longer stroke on the crank.
 
thanx alot guys..and i will let you know how it is coming with some pics.
 
Definately:wheel:
 
here are some pics of what i got done today. is everything supposed to look that toasty? there is no sludge at all...everything is just gritty and burnt like.
DSC00689.jpg

DSC00687.jpg

DSC00686.jpg
 
this is the kit i am trying to build:

4.6L Low-buck, low CR "rockcrawler"

~ Jeep 4.2L 3.895" stroke crank
~ Jeep 4.2L 5.875" rods
~ Keith-Black Silvolite UEM-2229 +0.030" bore pistons
~ Increase piston dish volume to 30cc
8.8:1 CR
~ Crane #750501 192/204 degree camshaft
~ Ported HO 1.91"/1.50" cylinder head
~ Mill block deck 0.035"
~ Mopar Performance 0.043" head gasket
~ 0.058" quench height
~ 2.25" exhaust
~ Ford 24lb/hr injectors with stock 39psi FPR for '87-'95 engines, stock injectors with stock 49psi FPR for '96 and later engines
~ 231hp @ 4400rpm, 327lbft @ 2000rpm


where can i get these? Keith-Black Silvolite UEM-2229 +0.030" bore pistons
 
Sounds like a cool project. What is the estimated time it will take ya to finish everything?
 
^^That is what I did, minus the supporting mods (still running stock cam/injectors/head. I went with the H802CP pistons (i think, remembering off the top of my head here). I love the setup. took me from a 11.7 1/8th mile on 33's to a 10.6 1/8th mile on 35's
 
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