what i got, and what i need

[brokenujoint]

Ok guys, I'd like to show you what i've got going for my 4.6 stroker and get some opinions on what i should do from here on out.

I very much copied Dino's build.
Not looking for a monster race engine.
I have a rockcrawler and i want good torque and a long life.

Block: 96 cherokee #53020569
Head 94 #7120 head

crank shaft: 78 #3214723 12 counterweights,
crank rear main seal #05018594AA
Pilot bearing #53009180AB
AMC 258 Rods pn 318044 (71-81 707 casting with rod bolts
Pistons: sealed power 677P +0.020 #STL-677P20
Piston Rings: hastings +0.020 cast piston rigns #667
Rod bearings: Clevite 77 #CB-960P-20
Main Bearings: Federal mogul #FM7211m.030
main bearing studs:stock
Girdle spaced with 14 hardened 5/16" steel washers
Cam sprocket bolt and washer #83502890 and #J3173284
Crank harmonic balancer #3300292OT
Timing gear and chain: CLO-9-3127 (double roller)
oil pump: Melling high volume oil pump
Oil pressure sending unit: new off existing engine
Pioneer brass freeze plugs
Engine tech complete gasket set #J242L-47
Oil Pan: stock
camshaft: STOCK 96 cherokee 4.0 camshaft
Clevite 77 cam bearings #SH-549S
Lifters CRN-99278-12

HEAD 7120
port and polished with bowls cleaned up as well
stock valves. 3 angle valve job, reground valve seats
stock springs and hardware
head resurfaced, cleaned, and magged.
Pushrods: 4.0 stock rods

Ignition will be stock from existing motor. New cap, plugs, wires.
banks header
99+ intake manifold
68mm Dodge Dakota TB
custom adaptor.
FMS 26lb injectors FMS-M9395A302
Flow Kooler water pump

Engine was bored 0.020 over

SO WITH THIS INFORMATION, WHAT SHOULD I DO WITH THE HEAD?
Right now i have a stock head that has a mild DIY port/polish job. Thinking about sending it out to be properly ported.... I have a stock cam. For my application of wanting a strong, reliable 4.6 stroker but not a strip racing beast, is the stock cam with stock valves and stock springs do-able or am i wasting good potential hp? my 68mm tb and 26lb injectors... will they be overkill for a stock cam/valve set up? im only 0.020 so i dont think larger valves and an aggressive cam is in order..
Anyways .. please chime in.

[RAPTORFAN85]

With the stock cam you aren't going to loose a TON of HP and what you do loose will be higher in the RPM's so that won't really matter that much on a rock crawler. You will however have nice low end torque with the stock cam which is what you want. I would leave the head as is. You aren't going to gain anything were you want it (down low) by porting it out. In fact you may loose bottom end torque but gain top end HP by porting it out. That's the trade off with porting, and besides, with the stock cam you won't be flowing enough air to make big gains by porting anyways. Stock cam,springs and push rods is definitely doable and should be a good combo for what you are looking for, a strong low end and reliable motor. Bigger valves should be out of the question for you, they aren't going to give you any real benefits, again because of the stock cam. Those should only be considered on top end builds were lots of high RPM HP is the goal. 68mm TB might be a little over kill and will have a very touchy throttle, not always the best thing when trying to crawl over a big obstacle, and the 26LBS injectors might be a little too big but run them and see how they work, the might be fine.

[Cheromaniac]

With the stock cam you aren't going to loose a TON of HP and what you do loose will be higher in the RPM's so that won't really matter that much on a rock crawler. You will however have nice low end torque with the stock cam which is what you want. I would leave the head as is. You aren't going to gain anything were you want it (down low) by porting it out. In fact you may loose bottom end torque but gain top end HP by porting it out. That's the trade off with porting, and besides, with the stock cam you won't be flowing enough air to make big gains by porting anyways. Stock cam,springs and push rods is definitely doable and should be a good combo for what you are looking for, a strong low end and reliable motor. Bigger valves should be out of the question for you, they aren't going to give you any real benefits, again because of the stock cam. Those should only be considered on top end builds were lots of high RPM HP is the goal. 68mm TB might be a little over kill and will have a very touchy throttle, not always the best thing when trying to crawl over a big obstacle, and the 26LBS injectors might be a little too big but run them and see how they work, the might be fine.

Agree with everything he said.

[brokenujoint]

sounds good then. with the head. i've done a very mild port on the exhaust and nothing else. i guess i will stop right there. should i go with 24lb injectors over the 26? lastly, can i swap out my 4.0 harmonic balancer on my engine and put in on the 4.6, or do i need a balancer for a 4.2L since its a 4.2L 12 wt crank?

[Cheromaniac]

sounds good then. with the head. i've done a very mild port on the exhaust and nothing else. i guess i will stop right there. should i go with 24lb injectors over the 26? lastly, can i swap out my 4.0 harmonic balancer on my engine and put in on the 4.6, or do i need a balancer for a 4.2L since its a 4.2L 12 wt crank?

You can do a good pocket port job on both the intakes and the exhausts to improve flow, and gasket-match the intake ports.
The injector size will depend on the model year of the Jeep they're going into. OBD 1 or OBD 2? 39psi regulator or 49psi?
You'll need the 4.0 harmonic balancer.

[brokenujoint]

its into a 1997 jeep wrangler, so its OBDII

[Cheromaniac]

The FMS-M9593A302 injectors that you have are the same 24lb'ers that I have. They're not rated at 26lb/hr but they'll flow 26.9lb/hr at a fuel pressure of 49psi. Should be OK since that's only 15% higher than the stock '97 injectors and you've also increased displacement by the same amount.

[brokenujoint]

OK, got the short block put together. numbers are as such:

bore: 3.895
stroke: 3.895 (3.875 is stock, this is 0.020 over so that would be 3.895 correct?)
CC: 58 (stock head)
deck clearance (non decked block with sealed power 677's). sits 0.021 under the deck
gasket: 0.043
dome/dish 17.5 cc
rod length: 5.875
cam intake duration: 253.3 (stock cam)
cam lob seperation angle: 114.3 (stock cam)
advance or retard: 0

totals
cubic inches: 278.46
liters: 4.56
SCR: 9.6
DCR: 7.94
Quench: 0.064
intake valve closing angle: 60.95

with this, should i polish the combustion chamber out or just let it be the way it is? its a low rpm, high tq motor. intend to gasket match the intake manifold and the heads intake to the gasket as well and smooth out the exhaust ports w/o taking much off.

[Cheromaniac]

You don't have to polish the combustion chambers but it would be a good idea to make them as smooth as you can, remove any rough spots, and feather the edges a bit. Same goes for the piston dishes. This will reduce the risk of preignition.

[gradon]

That calculator doesn't have an input for the piston pin height--the 677s are listed as a 1.585" comp height and 14.0cc dish(did you measure them to be 17.5cc?). If you go to the general discussion tab, you'll see another calc there where you can put your info in. Also the HG is .044" now. So with those #'s, I'm getting ~9.52scr .0455" deck clearance(stock is .021)+.044" HG=.0895" quench.

[brokenujoint]

i get some discussions where they say the pistons are 17.5 and some say 14. i thought they were 14. with your numbers if they are correct, that quench is pretty bad.. should i clean up the CC to get it down?

maybe im reading it wrong but dino's site http://www.angelfire.com/my/fan/selection.html says they are 17.5

by Cheromaniac » July 31st, 2009, 7:52 am
Stock 4.0 cast aluminium '87-'93 #83500251, '94-'95 #4773157, '96-'06 #4798329----1.601" 13.1cc
Keith-Black Silvolite (UEM) cast aluminium 2228/2228c----1.581" 11.5cc
Keith-Black Silvolite (UEM) cast aluminium 2229/2229c----1.581" 11.0cc
Keith-Black Silvolite (UEM) hypereutectic 3238hc/3243hc, 3241hc/3242hc----1.592" 13.7cc
Sealed Power (Sterling) hypereutectic H802CP/H825CP----1.592" 15.1cc
Sealed Power (Sterling) cast aluminium 677P/677CP----1.585" 17.5cc
Sealed Power (Sterling) cast aluminium 525P/525CP----1.580" 17.5cc
Keith-Black Silvolite (UEM) forged stroker 944----1.353" 21.7cc NEW
Keith-Black Silvolite (UEM) forged stroker 945----1.353" 11.4cc NEW

[gradon]

I got specs on the Sealed Power pistons from their tech dept last May and you can find them in our available piston faqs.

[Cheromaniac]

I actually cc'd the 677P's at 17.5cc and I checked two to make sure it wasn't a fluke. It surprised me too 'cause I was expecting them to be about 15cc.