4.0 Engine Toast - Considering Stroking

[Cheromaniac]

Going to break down my engine this weekend so a machine shop can check my block.

I noticed yesterday my head is 0331



I never overheated the engine but I'm very hesitant to put ANY money into this head. I'm not too sure what to do with it, I'd like to port and polish whatever head I end up using in the end. Should I break the entire head down and have it hot tanked and magnafluxed and then go from there? Would I be able to reuse stock components doing this or should I just let everything be and ride on it if the components are within spec?

You're lucky enough to have a head that's a reinforced TUPY casting so, with any luck, it should last longer than your Jeep. If hot tanking the head followed by magnafluxing doesn't reveal any cracks, do a DIY port job on it, and reuse all of the stock valvetrain components except for the cam/lifters.
If you go for a stock replacement cam with new lifters, you can even reuse your existing timing set as long as the chain deflection is less than 1/2" and the teeth on the cam/crank sprockets aren't worn.

[SilverXJ]

You're lucky enough to have a head that's a reinforced TUPY casting so, with any luck, it should last longer than your Jeep. If hot tanking the head followed by magnafluxing doesn't reveal any cracks, do a DIY port job on it, and reuse all of the stock valvetrain components except for the cam/lifters.

x2 It will be fine if it checks out otherwise.

[mikalcarbine]

I did see the TUPY stamp, I had no idea that it meant it was reinforced, this is great news, I'll hopefully be pulling it apart soon I'll keep you all posted

[mikalcarbine]

I just tore the engine down today minus taking the head/lifters out (need to pick up a 12mm 12 point deep socket haha)

My timing chain had 7/16 of play, FSM says if it's more than 1/2" to replace it. I'll definitely be replacing it for safe measure, what about the timing sprockets?



I can snap a pic of the inside crank/camshaft mating surfaces if that is more critical than the teeth

I labeled all of the rockers, bridges and pivots in egg cartons to keep track of them, I didn't look at the wear on them yet



Ready for the mains to come off


IMO the front main journal looked really good



Main 3


Main 4


Main 5


Main 6


Main 7


It seems like the wear gets worse towards the rear

Ready and waiting for the head to be pulled

[SilverXJ]

If you are going with an earlier style cam you will need a new timing set anyhow unless you get a new stock cam or custom later cam. Either way I recommend replacing the chain and gears as a set.

Interesting way to take it apart... usually the head is taken off first then you work your way down.

[mikalcarbine]

Haha after realizing I didn't have a 1/2" 12 point I didn't want to stop, the lifters are hanging out in purgatory after flipping the engine

The camshaft definitely has some funky wear, could you recommend a mild timing for a cam that could run on stock springs? I'm going to do some more SCR, DCR and cam timing reading before actually calling some of the cam manufacturers. I figure if I'm replacing the camshaft I might as well go with a mild performance upgrade

[Knoxes]

It looks like you have the cam retaining plate - I just went through all these mental machinations...

If you want to use the retaining plate, you have two choices - the stock cam or a custom cam. There isn't an off-the-shelf aftermarket that uses the retaining plate. I'm going with the stock cam because the grind on the custom cam would require performance springs, which means a new performance timing set, which isn't easily compatible with the snout on the RP cam. It was an easy decision to stick with the stock cam once I considered all of the ancillary issues associated with the custom cam. There may be other custom cam builders that can grind within the 440 spring rate on the stock springs, but the guy that is generally recommnended on here couldn't build anything that small.

If you don't care about the retaining plate, then you can use an aftermarket cam, but you have to modify the timing cover to work with the spring/pin to adjust the endplay. I never got a clear understanding of how that worked, and/or how reliable it would be. It may be a piece of cake - I just don't know. I know that it's been done many times. The added benefit to this setup is that you can use a nice Cloyes double roller timing set. However, since I couldn't get my head wrapped around that mod, I went with the stock cam/timing plate/retainer/springs/timing set/etc.

[Cheromaniac]

I did see the TUPY stamp, I had no idea that it meant it was reinforced, this is great news, I'll hopefully be pulling it apart soon I'll keep you all posted

TUPY is the name of the Brazilian company who made those reinforced castings from '02 onwards.

[mikalcarbine]

It looks like you have the cam retaining plate - I just went through all these mental machinations...

If you want to use the retaining plate, you have two choices - the stock cam or a custom cam. There isn't an off-the-shelf aftermarket that uses the retaining plate. I'm going with the stock cam because the grind on the custom cam would require performance springs, which means a new performance timing set, which isn't easily compatible with the snout on the RP cam. It was an easy decision to stick with the stock cam once I considered all of the ancillary issues associated with the custom cam. There may be other custom cam builders that can grind within the 440 spring rate on the stock springs, but the guy that is generally recommnended on here couldn't build anything that small.

If you don't care about the retaining plate, then you can use an aftermarket cam, but you have to modify the timing cover to work with the spring/pin to adjust the endplay. I never got a clear understanding of how that worked, and/or how reliable it would be. It may be a piece of cake - I just don't know. I know that it's been done many times. The added benefit to this setup is that you can use a nice Cloyes double roller timing set. However, since I couldn't get my head wrapped around that mod, I went with the stock cam/timing plate/retainer/springs/timing set/etc.

What build are you going for? When you say stock cam do you mean the stock 4.0 cam or are there other cams that mate with the "stock" 4.0 components but have different lobe characteristics?

The engine is broken down entirely now, I'll post some pics later. I've begun shopping around for machine shop prices, a coworker recommended this one shop and said they're pricey but he's had them do work and their quality, here are the prices I got from them

Block
Hot tank...$80.00
Magnaflux...$90.00
Line hone and main bearing bores...$295.00
Check cylinders for roundess and hone...$160.00
Maybe* Bore and hone to 0.030"...$295.00
Mill Block Deck 0.035"...$150.00
Install Cam Bearings...$75.00
Install Freeze Plugs...$15.00

Crankshaft
Hot Tank...$20.00
Magnaflux...$55.00
Polish main and rod journals...$65.00
Grind mains and rods if necessary...$230.00
Chamfer oil holes...$35.00
Balance with HB and FP...$330.00, includes Rods and Pistons

Connecting Rods
Hot Tank...$20.00
Shot Peen...$150.00
Check for Straightness...$20.00
Install ARP Rod Bolts...$150.00 with resize
Resize Bearing Journals...included above with Install ARP Rod Bolts
Weight Balance...Included with Crankshaft Balance
Install Pistons...$35.00
Intake Manifold
*Maybe* Check for flatness...$25.00

Exhaust Manifold
*Maybe* Check for flatness...Included with Intake Manifold

Cylinder Head
Hot Tank...Hot Tank & Magnaflux...$90.00
Magnaflux...See above...
Valve Stem Seals...$475.00
*Maybe* 3 angle valve Job...See above, included
Check tolerances and assemble Springs...See above...included
*Maybe* mill block deck...$95.00

Do some of these seem a little too excessive? I haven't received other prices yet but from the FAQ something like shot peening the rods should average around $30 yet these guys are charging $150? I'm not 100% familiar with the process but I must imagine there are different ways to do this with varying costs

I'll keep shopping around in the meantime, I'm scheduled to go visit their shop tomorrow and sit down with them

[SilverXJ]

I'm going with the stock cam because the grind on the custom cam would require performance springs, which means a new performance timing set, which isn't easily compatible with the snout on the RP cam.

The late style Morse silent link timing set is much stronger than the early single row stock replacement set that there have been failures with. The Morse silent link will hold up fine with an upgraded valve train.

[Knoxes]

What build are you going for? When you say stock cam do you mean the stock 4.0 cam or are there other cams that mate with the "stock" 4.0 components but have different lobe characteristics?

I'm doing the 4.2 mini-stroker. I chose this because of the projected costs, which should be cheaper than a 4.6-7 build. However, I've already blown past my projected budget, and I'm just starting re-assembly and have a host of parts left to buy. Because of the stock cam choice, I'll get only nominal performance improvements. It'll be slightly better than stock. If I had it to do all over again, I would do the 4.6.

No, I mean the stock 4.0 cam.

http://www.angelfire.com/my/fan/Jeep4.0Camshafts.htm

See the second column under the Jeep 4.0 heading. All the cams on that list are built for the 4.0L L6 engine, but none of the aftermarket cams will work with our block (post 1996?) without some modification.

I'm going with the stock cam because the grind on the custom cam would require performance springs, which means a new performance timing set, which isn't easily compatible with the snout on the RP cam.

The late style Morse silent link timing set is much stronger than the early single row stock replacement set that there have been failures with. The Morse silent link will hold up fine with an upgraded valve train.

Very good to know.

[mikalcarbine]

Do you have a build thread or excel sheet with your coats? I'd love to see this

[mikalcarbine]

Just visited my first machine shop today to get prices, we worked out what I did and did not need to do. As of now here is what I'm looking at for machine labor here

Block
Hot tank $80.00
Check cylinders for roundness and hone $160.00
Install Cam Bearings $75.00
Install Freeze Plugs $15.00

Crankshaft
Hot Tank $20.00
Magnaflux $55.00
Grind mains and rods to 0.010 $230.00
Chamfer oil holes $35.00
Balance with HB and FP $330.00

Connecting Rods
Hot Tank $20.00
Magnaflux $45.00
Resize Bearing Journals As Needed $55.00
R&R and install pistons $60.00
Increase piston dish volume to 18cc $60.00

Intake and Exhaust Manifold
Check for flatness $25.00

Cylinder Head
Magnaflux $45.00
Valve stem seals, performance valves, 3 angle valve job, assemble springs, clean head if needed $475.00

This totals about $1,800 in machine labor plus $450 for the short block assembly. Add about $1000 in parts and I'm $3,250 deep for a "mild" stroker. I'm going to visit 2 or 3 more shops before I make up my mind. At this rate I could spend another $1,000 and get a high performance crate stroker. The shop recommended the crane 753901 grind H-260-2 cam and said I wouldn't need to worry about a cam pin/spring and it should work with my stock retaining plate?

[SilverXJ]

Crankshaft
Hot Tank $20.00
Magnaflux $55.00
Grind mains and rods to 0.010 $230.00
Chamfer oil holes $35.00
Balance with HB and FP $330.00

Holy crap.. you can buy a new crank for less.

The shop recommended the crane 753901 grind H-260-2 cam and said I wouldn't need to worry about a cam pin/spring and it should work with my stock retaining plate?

No it won't work with the retaining plate and yes you still need a pin and spring if you go with that cam. A solid pin would be better.

[mikalcarbine]

Do you know of any pictures that shows this can pin setup?