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TrojanMan
12-04-2005, 06:45 PM
Disclaimer: I do not recommend nor endorse any of the modifications shown in this article; the information is provided for personal information purposes only. I am not an Engineer, metallurgist, or mechanic - I have absolutely no professional qualifications whatsoever in this regard - I have simply collected information from others and from my own experience. Use of any of the information contained herein is at your own risk. It is therefore your responsibility to maintain safety in and around your vehicle at all times. It is likely that some procedures featured here may void your vehicle’s (or parts thereof) warranty. It is also likely that some of the information featured shows procedures that may not be legal for street use in some or all states within the US and/or any other countries and may not be safe for on or off-road use. The article's author, or anyone related to this web page, cannot be held responsible for any damage, failure, or violations of the law, that might result from the use of any information contained on this page, or linked to on this page.


So I’ve noticed a lot of people lately having power issues with their 4.0 and considering serious engine modifications. Aside from bolt-ons (which can give you some more power but usually isn’t enough to turn those bigger tires) you’re left with two options : doing an engine swap like a Chevy 350, AMC 5.2 or 5.9, or any other engine or stroking. While the 350 is a very tried and true selection and possibly the most common sb v8 with the most aftermarket support, it requires a lot of other modifications, such as motor mounts, transmission, computers, wiring, etc. and becomes a mess. If your jeep is not a DD this would be a good swap to do, but it is going to take some downtime to do. It also requires a good bit of money, considering all of the parts you have to buy beyond the engine. If you buy a junkyard motor you also run the risk of finding one that needs a total rebuild, which is another costly thing. The 318 and 360 are good swaps to do, because they did come in grands so you can just find a junkyard 5.2 or 5.9 and take all the parts you need (or head over to the dealer). A little less fabrication is needed here – yet you still do need all of the extra parts. With a stroker the only thing that changes is the internals of the engine. You retain all of your stock sensors, harnesses, transmission, etc. etc. In a nutshell stroking is simply putting in a larger crankshaft, smaller rods, and doing an overbore. This combination results in a larger displacement.

The most common strokers are the of the 4.5-4.7 variety (4.6 possibly the single most common) and use the crank and rods from the AMC 4.2L inline 6. A stock pin height piston is used with your selected overbore. The bore you choose is dependent on the shape of the motor and your preference on displacement. This write-up will focus on the 4.6 variety, as that is what I built. I am estimating 240 HP and 335 ftlb (only 5 hp and 10 ftlb less than the 5.9). I have yet to do a dyno run; however that is soon to come. A well build stroker with ported heads, all accessories, and the right cam can achieve 260 HP and 325 ftlb, however this is a little beyond the scope of the average “budget” stroker.

Before you begin any work on your own stroker, I highly suggest you read over the information here, as well as Dino’s site, and the FSM’s engine overhauling section many times. You cannot know too much information when it comes to building an engine. Factory Service Manuals can be purchased from Dirk (Cue) very cheap, in .pdf format on a CD. I printed out the engine pages and blow up diagrams located in the parts diagrams, I found this information to be VERY handy while working on the engine. The FSM provides very detailed information, highly accurate diagrams, and all the torque and other specifications you’d ever need to know to build an engine. No mechanic should be without one.

First I’ll describe a little bit about my stroker. I use the 4.2 crank and rods from an 89 YJ, because the snout length on the crank matches the snout length of the 4.0 crank (I’ll discuss this further later on in the write-up). I am currently using the sealed power 677P pistons with a .030” overbore. I was going to use the H802CP pistons, however the factory sent me the wrong bore size and in the name of getting the stroker built quickly I went with the pistons I had on hand. I am using a sealed power RV cam with the following specs:
Duration: 208/208 degrees @ 0.050" lift
Lift: 0.448"/0.448"
Lobe separation angle: 110 degrees
Nothing too crazy, however it gives a good amount of low end torque, which is desired for off-road driving. I did a port and polish in my garage using a die grinder and the standard abrasives port & polish kit (which will be discussed later also) and used the 5.9 performance valve springs. My head was decked .017” a year before due to overheating and warping, I liked this number so I reused the head. The result of my decked head and higher performance pistons is a healthy 9.5:1 compression ratio. Had I used the H802CP pistons I originally wanted, I would have been looking at a 9.8:1 CR. This means I have to run on 93 octane gas, but it only ends up being 2 or 3 dollars more per fill-up. I’m using a borla longtube header for maximum low end torque. It is perhaps the most expensive header, but also happens to be the most powerful and has an excellent warranty.

Now for the more general tech: First I’ll discuss the crankshaft. The crankshaft used in a 4.6L stroker is the AMC 4.2L crankshaft. This crankshaft shares the same size and location for the main bearings, which means it bolts directly in. The following casting numbers and details are found on Dino’s site (http://www.angelfire.com/my/fan/selection.html)
Year.........Casting No......Description
1971.........3199738.........For Borg Warner automatic
1972-80...3214723.........12 counterweights, 66lb, 64mm nose
1981-86...3235477.........4 counterweights, 46lb, 64mm nose
1987-90...3727...............4 counterweights, 46lb, 54mm nose

For comparison, the 4.0 crankshaft has 8 counterweights, weighs 55lb, and has a 54mm nose.
The #3214723 crank is reputed to the the strongest. The extra counterweights dampen vibration-inducing harmonics to produce a smoother running engine.
The 12 CW crank has more rotating mass, which means it is harder to slow down – which makes it more resistant to stalling. While this is desired, the 4.6L stroker is fuel injected and thus stalling out is not as much of an issue. The 87-90 crankshaft is the easiest to work with because it has the same nose length as the 4.0 crankshaft. In order to use the 71-86 crankshafts, a 1cm spacer has to be machined and put on the nose in order to get the harmonic dampner pulley located in the right spot. Because of this reason, I chose the 89 crankshaft. I purchased my crankshaft from advance auto parts. It was more expensive than the junkyard route, however it came to me remanufactured – meaning it came with the correct dimensions, matching main bearings, and even cam bearings.

The main girdle located on 96+ 4.0 engines is a good thing to have, it ties together all of the main caps – thus providing more rigidity and decreasing noises/vibrations. Using this girdle requires the main bolts from a 96+ 4.0, as it has the stud on top of the bolt that the girdle rests and bolts onto. The main caps that came with the block can be reused, however because the 4.2 crankshaft is larger than the 4.0 crankshaft, the girdle has to be shimmed up to clear the larger crankshaft. To do so, simply put 2x 3/8” washers in-between the main cap and girdle. There will be just enough thread left on the bolt to safely secure the girdle down. These can be bolted down to stock specification.

The stock oil pump can be re-used, but my oil pump was already 128K miles old. I decided to go ahead and replace the oil pump while I had everything out. Instead of going with the simple stock oil pump I wanted a little more flow, so I got the high volume oil pump from advance auto parts. When installing the oil pump, I recommend removing the access plate and packing the pump full of Vaseline. This provides more suction and instantly gets oil pumped to the rest of the engine on initial startup, rather than having a few seconds of dry running which can cause undesired damage. Instead of this you can also use a drill to turn the oil pump before starting to get oil pumped through, or buy a pre-oiler (which is most desired, but again isn’t the best option for a budget build… a pre-oiler can always be installed later on if desired).

The rods from the AMC 4.2L I6 are used, as it has the same pin bore as the 4.0 (which allows for the stock type 4.0 piston to be used) and fits perfectly (obviously) on the 4.2L crankshaft. The piston you use is up to you, every piston has different pin heights and dish volumes. The following part number and information are also pulled from Dino’s site:
Stock 4.0 cast aluminum '87-'93 #83500251, '94-'95 #4773157, '96-'04 #4798329----1.601" 13.1cc
Keith-Black Silvolite hypereutectic #2228----1.581" 11.5cc
Sealed Power hypereutectic H802CP----1.592" 15.8cc
Sealed Power cast aluminum 677P----1.585" 17.5cc
The smaller the dish volume you have, the smaller the combustion chamber, and thus the higher the compression ratio. If you get the 677P pistons like I did, the part numbers for the rings are:
SLP-E-245K030 is the part number for moly Sealed Power rings, a set of 8 @ 50 bucks
SLP-WE-245K-30 is the part number for the same ring, only in a single piston set @ 15 bucks
TSR-S0660-30 is the part number for the Total Seal ring. It has a gapless 2nd ring and I would highly recommend it for anybody who has the extra money to throw down, they're 150 for a set of 8.
The land sizes on the 677P are 5/64 5/64 3/16. I highly recommend the total seal rings if you can afford the extra 100 bucks. Total Seal is a much better ring, and reduces blow-by and provides a much better seal.

Camshaft choice is another important aspect of the stroker build. If you are going with the absolute low buck stroker you can re-use the stock camshaft, but only with a compression ratio up to about 9.1. Anything above that has too high cylinder pressures and can cause detonation. A list of camshaft specs is found on Dino’s site http://www.angelfire.com/my/fan/Jeep4.0Camshafts.htm (http://www.angelfire.com/my/fan/Jeep4.0Camshafts.htm). The cam you choose can either give you lots of low end torque but low HP, or high HP and not as much lower end torque. If your jeep doesn’t see much insane offroading that often and is a solid DD, you may want to consider a camshaft with specs in-between to give you enough power on the road as well as on the rocks, or if you spend a lot of time in the mud and require power throughout the rpm band.

The timing set from the 4.0 engine will work just fine, however you may choose to upgrade to a dual roller timing set. The stock distributor will work, as well. However some modification of the distributor is required when putting in an aftermarket cam. The tabs on the distributor must be cut off, as the distributor will not align the same as with the stock cam. This is due to a slight difference in the gearing of the cam. No worries, however, as the clamping action of the retainer and bolt is sufficient to hold the distributor from rotating during usage. I have 2,000 miles on my stroker and it hasn't budged, Aaron Clements has 10K on his and reports the same thing.

The cylinder head is the final consideration for the stroker. The intake valve on the 4.0 is 1.91” and the exhaust is 1.50”. The following casting numbers are again thanks to Dino:
Year............Casting No
1987-90......2686
1991-95......7120
1996-98......0630
1999-04......0331
As a matter of fact, I’ll just copy the following paragraph from Dino, as I cannot write it any better.
The early '87-'90 non-HO heads have low intake ports that flow rather poorly. The later HO heads have higher intake ports that flow more air by allowing a straighter shot into the cylinders. The '91-'95 HO heads with casting no. 7120 have the highest intake and exhaust port airflows, especially at lower valve lifts where it is most important, and are the best for performance. The '96-'98 0630 heads are almost identical except that they don't have a port for the coolant temp. gauge sending unit. The '99 and later WJ heads with casting no. 0331 have smaller exhaust ports to produce a faster warm-up of the catalytic converter and improve emissions, but performance also suffers because the ports don't flow as well as those of the 7120 and 0630 castings. The 0331 heads are also prone to crack if the engine overheats so these should preferably be avoided. All of the 4.0 heads respond well to a good port job, with gains of up to 20hp possible on a 4.6L stroker engine.

As far as fuel is concerned, almost all stock fuel delivery components are used, excepting the fuel injectors and possibly the MAP sensor. Most people use 24# FMS injectors found most commonly on mustangs. These injectors are easily identifiable by their blue color.

TrojanMan
12-04-2005, 06:45 PM
An adjustable MAP sensor is desired but not required, it allows for tweaking of the air/fuel ratio to get the perfect 14.7:1 ratio. You can either use one of a homemade variety such as Dino’s : http://www.angelfire.com/my/fan/MAP_adjuster.html (http://www.angelfire.com/my/fan/MAP_adjuster.html) or the more accurate and powerful (but consequently vastly more expensive) A'PEXi Super AFC II Fuel Computer. Aaron Clements used one of these in his ’91 XJ with a 4.6L stroker and has had great success with it. I can personally vouch for the success of this computer. Aaron did a good write-up on how to install one in his XJ; however the information can easily be converted into your own personal application fairly easy. Here is a link to Aaron’s write up: http://www.naxja.org/forum/showthread.php?t=46515 (http://www.naxja.org/forum/showthread.php?t=46515) .


Now for a quick description of the stroking process: I’ll describe the problems I faced and how I dealt with them, to possibly give you an idea of what to look out for.

I began with a complete 4.0 courtesy of a friend of mine for 400 bones. The block was already bored .030 over, so I did not have to worry about that. The first step was to bring all of the parts to the machine shop for prep work. The block was brought to be checked for any problems (such as cracks) and to ensure that the pistons would work well with the bore (with hypereutectic pistons a very tight tolerance is given to the bore). I brought the crank, rods, pistons, main caps, bearings, and flex plate as well. I had the shop do a balance on the rotating assembly to provide for the smoothest engine possible. This was the most expensive part of the machine shop work, but worth every penny. At idle at a stop light you can’t even tell my engine is on unless you look at the tachometer. I also had them press the pistons on to the rods. This is when I found out that I was sent the wrong overbore – I’m not sure if this was a miscommunication between the supplier and me or if it was a mistake in shipping. Either way I had to get the engine running as soon as possible so I went with the 677P that came with the 4.0 I bought. I sent the H802CP pistons back and exchanged them for the correct bore size, as well as bought the correct piston rings for the 677P pistons. When the block work was done I dropped my head off to be disassembled and dipped in the tank to be cleaned. I then took the head, did a port & polish, then took it back to the shop to be cleaned again (to remove any small metal particles) and did a 3 angle valve job. Information on how to do a port & polish by yourself is found on Dino’s site http://www.jeep4.0performance.4mg.com/head.html (http://www.jeep4.0performance.4mg.com/head.html) The only thing I can add to Dino’s port and polish write-up is that if you get a carbide bit (I got a ¼” shank, double cut, tree shape shaped bit) the cutting goes much faster. The carbide cuts into iron like a hot knife through butter; it is used for removing bulk material. You then go in and use the sanding bits to smooth it all out. I believe the number for the carbide bit is SG-5 and can be found at www.wttool.com (http://www.wttool.com/) . When all was said and done, the final bill was around 450 dollars. It was expensive, but necessary.

Next was the assembly of the block. The first set of main bearings I got with the crankshaft were bad and had to be returned. One of the bearings had actually been pressed into the other during the manufacturing process. I went to advance auto parts and was given a fresh set of bearings free of charge. Next I laid the block on a dolly that was comfortable to work on. I then put the top half of the main bearings into the block, installed the rear main seal into the block and into the number 7 main cap, set the crank on top of the bearings, put the bottom half of the bearings into the main caps, put a piece of plasti-gauge in-between one of the bearings and the crank, and bolted all caps to spec. I was satisfied with the clearance, it was within spec. I then checked the other bearings with plasti-gauge and was satisfied with all of the bearings. Next step was to press the piston rings onto the pistons. Thanks to the piston ring expander tool from craftsman this was a quick and easy task. After the rings were pressed onto the pistons, I set them in oil overnight to soak. The following day I used a piston ring compressor and slid the pistons into the block. This was best done with the block on an engine stand so that it can be rotated over. It is important to remember the order of the rods (1-6) if you had them balanced, as putting one out of order will result in a wasted balance. Remember, also, to place pieces of rubber hose over the rod bolts to protect the cylinder walls from scarring during the installation process. Once the piston is in I popped a bearing in on the rod side and on the rod cap and bolted it together with plasti-gauge to check for clearances. Repeat this procedure for all pistons. I was not happy with the bearings I got; they showed to have too much clearance. I returned these bearings and got a fresh set. The new ones proved to be much better. Once all rod caps are installed, the next step is to bolt on the main girdle. My first mistake was getting the wrong size washers. I originally purchased 5/16” SAE washers as Dino recommended, but for some reason they did not work with my 96 main bolts. I had to return to the hardware store and buy 3/8” SAE washers. I put one washer on every stud, placed the main girdle on top, and bolted it all down to spec (35 lbft). Next, just to make sure, I put a bolt into the nose of the crank and spun the crank over, only to find that the counterweights were bottoming out against the main girdle. This posed a problem, so I went and bought 14 more SAE washers and stacked them under the girdle. This left just enough thread on the bolts to provide for a safe tightening. The spinning check showed that the crank will spin without interference from the main girdle. This was good news. I then installed the oil pump and as stated before, I loaded the pump with Vaseline to ensure a safe start up. Next step was to put the oil pan gasket on and bolt up the oil pan. I used grey RTV on both sides of the gasket to ensure no oil leaks would occur from the pan. Finally I slid the camshaft into the block (I had the machine shop install the cam bearings). Next I slid the sprockets onto the camshaft and crankshaft, and aligned them for proper timing. To do this, set the number one cylinder at TDC (top dead center). The notch on the sprocket should be pointing at the camshaft sprocket. Align this notch with the notch on the camshaft sprocket and remove the sprockets, keeping them aligned. Slide the chain over the sprockets, and put them back onto their respective shafts. The notches should still face each other perfectly. If they do not, pull the camshaft sprocket off and adjust the chain until the notches align perfectly. Once you have this set, install the oil slinger and thrust pin and bolt on the timing cover (again using Grey RTV on the gasket to prevent leaks).

Once the short block was complete it was time to build the head. Before I started to assemble the valve train I soaked the lifters in oil, as they need to soak for one day before installation. I slid the stock valves into the head, pressed a new stem seal over the stems, placed a spring retainer on top of each spring, compressed the springs, slid them over the valve stem, and locked them in place. Stock locks can be used with the 5.9 performance valve springs and retainers. Now that the head was built I dropped a lifter into each valley, set the head gasket on, and dropped the head onto the block. I then bolted the head down, using the proper torque technique described in the FSM. Once the head was down, I slid a pushrod onto each lifter and bolted the rocker arms down. Next you place the valve cover over the head, using a gasket and more grey RTV. Bolt the valve cover to the head carefully; these bolts do not require much torque. You will either end up tearing the head off of a bolt or bending the valve cover if you apply too much pressure. Always remember to refer to the FSM for proper torque specifications. Next step was to install the distributor. Again, Dino’s site provides the best resource on how to do this properly. As a side note from his site, I had to grind off both tabs of the distributor to offer maximum rotation for fine tuning. Dino’s distributor indexing site is: http://www.angelfire.com/my/fan/dist_index.html (http://www.angelfire.com/my/fan/dist_index.html) . Finally you install all of the accessory type things, such as the thermostat, water pump, all brackets, alternator, etc. From this point on, installation into the vehicle is no different than that of a regular 4.0 engine.

Overall I am very satisfied with my stroker. I have no regrets about any of it. I have all the power I have ever wanted and probably will ever need. She is well mannered on the road and while I have not had a chance to test her off-road – I feel fully confident that she will perform better than the competition out there. I am getting good fuel mileage, however I cannot quote any specific numbers because it is constantly changing with the weather and it improves as the engine breaks in more. I have noticed approximately 18-20 MPG while cruising back roads, however.

If there is any information that I left out or you would like to see discussed, please let me know. I highly doubt that in 7 pages of information I got everything right and didn’t forget anything. My email is dross50@msn.com (dross50@msn.com), you can private message me, or simply post in this thread. I will respond to all questions as accurately as possible – and if I do not know your answer right away I will help you find an answer.

I must give credit where credit is deserved. Dino Savva is possibly the most knowledgeable man I have ever met when it comes to the 4.0 engine. If it wasn’t for his sites I would have never been able to accomplish this build. He is also willing to help with many questions. He can be found on jeepsunlimited.com and naxja. His sites are:
http://www.jeep4.0performance.4mg.com/ (http://www.jeep4.0performance.4mg.com/) and
http://www.angelfire.com/my/fan/stroker.html (http://www.angelfire.com/my/fan/stroker.html) .
I based some of this write-up off of his site, yet tried to keep it as unique as possible. I cannot possibly express the level of gratitude I have for Dino and what he does. Also, great credit is due to Aaron Clements for many phone calls in various odd hours of the day. He is also a very informative person about the stroker. His screen name is MrShoeBoy – he can be found here, on jeepsunlimited, and on naxja. Both of these men can probably help you more than I can about the stroker, however I will attempt to provide every bit of assistance I can to lighten their load. If you made it all the way to the end of this write-up – congratulations! Now go build a stroker!

David

rob92xj
01-18-2006, 03:25 PM
Good write up David.

TrojanMan
01-18-2006, 05:30 PM
Thanks :rock:

The jeep is up here in raleigh now, you should come check it out.

rob92xj
01-21-2006, 02:20 AM
Or you could come down and we can get some others together for one of Stinkomans endless runs on a local trail.

death-mobile
01-21-2006, 01:01 PM
Is it possible to stroke an EFI (non-distributer) 4.0 such as my 2000?

ELLLLLIOTTTTT
01-21-2006, 02:31 PM
Or you could come down and we can get some others together for one of Stinkomans endless runs on a local trail.

doubt that'd work... trojanwhore to SKEERD to go wheeling. :D

TrojanMan
01-21-2006, 03:45 PM
Is it possible to stroke an EFI (non-distributer) 4.0 such as my 2000?

Yep, you'll just retain your old ignition setup. The exterior is the exact same with the exception of a few things like the header, injectors, etc.

Justheman80
01-22-2006, 02:27 PM
Just curious, what is an aproximate cost of building a stroker including parts an nessissary machine work? Asuming you are doing most of the work your self.

TrojanMan
01-22-2006, 02:36 PM
I think Dino did his for 1400 but he ran into some incredible deals and used more used parts than me. Most of my parts were new and I clocked in at 1700 (not including the header). The more you put in the more you get.

rob92xj
01-24-2006, 08:08 AM
doubt that'd work... trojanwhore to SKEERD to go wheeling. :D
Thats true he punked out in December at the last minute.

death-mobile
01-26-2006, 12:18 AM
I'm so curious to witness a 4.6 in person. It seems like such an ideal build for the straight 6.

TrojanMan
01-26-2006, 12:40 AM
Thats true he punked out in December at the last minute.

Well I was on the road, about to turn onto carowinds blvd.. when I noticed I had a smoke screen behind me. I'm no James Bond, so that's bad.

StinkoMan20X6_
01-26-2006, 08:25 PM
What turned out to be the issue? Surely not a problem with the all mighty stroker!!! Actually if I had planned on keeping the jeep at the time I got the motor rebuilt I would have stroked it, unfortunately I was in a rush to get it rolling again so I could sell the bitch...but ended up keeping it. DOH!!!

TrojanMan
01-27-2006, 02:42 AM
What turned out to be the issue? Surely not a problem with the all mighty stroker!!! Actually if I had planned on keeping the jeep at the time I got the motor rebuilt I would have stroked it, unfortunately I was in a rush to get it rolling again so I could sell the bitch...but ended up keeping it. DOH!!!

Leaky valve cover gasket, it was leaking down onto the exhaust pipe. it took a while to fix because it was cold and I had to wait for the RTV to set.

TrojanMan
06-10-2006, 12:18 AM
This time i'm going to post pics and go more in depth with things step by step. At this point i've already disassembled the block and i'm about to start work on the head. First it has to be disassembled so I can take it to the machine shop to be cleaned.

Start by removing the rocker arms one by one, keeping the two arms together that are combined by a bridge. Keep these numbered, you have to reinstall them in order and together.
http://www4.ncsu.edu/~djross/jeep/headdis2.JPG
http://www4.ncsu.edu/~djross/jeep/headdis3.JPG
Notice how I have the bags put together:
http://www4.ncsu.edu/~djross/jeep/headdis4.JPG
This is the tool you use to remove the valve springs:
http://www4.ncsu.edu/~djross/jeep/headdis5.JPG
Here's how you install it on the spring and then compress it
http://www4.ncsu.edu/~djross/jeep/headdis6.JPG
http://www4.ncsu.edu/~djross/jeep/headdis7.JPG
To remove the valve spring locks you'll have to push up on the valve from the bottom of the head and tap on either the spring or the compressor with a hammer.
http://www4.ncsu.edu/~djross/jeep/headdis8.JPG
You can see that the locks are little pieces of metal that hug the valve, they come out fairly easy when freed with the hammer.
http://www4.ncsu.edu/~djross/jeep/headdis10.JPG
Now you can lift the valve spring off of the valve.
http://www4.ncsu.edu/~djross/jeep/headdis11.JPG
The spring retainer simply lifts off of the spring.
http://www4.ncsu.edu/~djross/jeep/headdis12.JPG
The valve slides out of the bottom of the head now
http://www4.ncsu.edu/~djross/jeep/headdis13.JPG
http://www4.ncsu.edu/~djross/jeep/headdis14.JPG
Now you have to remove the valve stem seal. Sometimes it helps to lightly tap a flathead screwdriver under the seal to pry it up. They should have a good seal on them of they've been in there a while and if they're worth anything. I found it best to get the screwdriver under the seal then twist the handle of the screwdriver. The stem seal lifts straight up.
http://www4.ncsu.edu/~djross/jeep/headdis15.JPG
http://www4.ncsu.edu/~djross/jeep/headdis16.JPG
Repeat process for all valves and this is what a disassembled head looks like ready to be taken to the machine shop:
http://www4.ncsu.edu/~djross/jeep/headdis17.JPG

More to come as soon as I get stuff back from the machine shop.

Cue-Ball
06-10-2006, 12:43 AM
Looking good Dave.

Dirk

86camo1ton
08-15-2006, 01:33 PM
David
My name is Jeff and I currently have an 86 CJ I bought the jeep from the second owner with 117,000 miles on it. The motor has a bad rear main seal leak and uses oil. This is my first jeep (81-87 chevy fan). The jeep still had the original computer controlled junk on it so I bought a clifford intake and had quickfuel build me a carb for it. I then modified a chevy distributor to eliminate the other boxes. So now for my question. I have read alot about building a stroker and this is the route I want to go. I bought a complete running 93 cherokee for $200.00. I plan on using the crank and rods out of my 86. I have read alot of articles on fuel injected strokers but none on carbs. How do you think this would effect cam choice, can I use my (chevy) distributor out of my 258? and there also seems to be a little confusion on what push rods to use. Any help would be greatly appriciated. I also noticed that the fan on the cherokee is offset can I simply get a fan pulley from a wrangler with the 4.0 and fix this problem? Great write up and info. Jeff

death-mobile
08-15-2006, 06:16 PM
Cool man.

TrojanMan
08-15-2006, 10:11 PM
Honestly I don't know a whole lot about carbs, I would head over to speed freaks on JU and ask dino. I would reccomend going FI, though.

86camo1ton
08-16-2006, 12:23 PM
How much trouble would it be for me to transplant the FI system from the cherokee into my CJ. I have worked with TPI and TBI but nothing on a jeep if they made a stand alone harness I might be interested. What about the fuel pump does it have to be mounted in the tank or can it be mounted close to the motor. Also it seems like I have read something about a crank positioning sensor and a problem with the bellhousing. My cherokee is a automatic and my CJ is a standard and I want to keep the standard in my CJ. Thanks Jeff

death-mobile
08-20-2006, 12:14 AM
I have a question about the head you used. If 95HO heads have the best flow and are the best choice for building a stroker, would it make sense if I were to port and polish a 95HO head now, and put it on my 00WJ? I was planning on pulling the head to port and polish and put a header on it this winter, but now I'm thinking I might be better off buying an older 95HO head and working that.

TrojanMan
08-20-2006, 12:21 AM
How much trouble would it be for me to transplant the FI system from the cherokee into my CJ. I have worked with TPI and TBI but nothing on a jeep if they made a stand alone harness I might be interested. What about the fuel pump does it have to be mounted in the tank or can it be mounted close to the motor. Also it seems like I have read something about a crank positioning sensor and a problem with the bellhousing. My cherokee is a automatic and my CJ is a standard and I want to keep the standard in my CJ. Thanks Jeff

I don't think it would be too tough to swap the FI, as long as you pull the computers from the XJ and find a place for them it wouldn't be too bad. I'm pretty sure swampy runs an external fuel pump - as long as you know what you're doing it doesn't really matter where the pump is so long as you get fuel out. The ckp sensor -might- work but I doubt it because of the year difference. You'll need to do a little research into ckp sensors as far as years and transmissions... I don't know what kind of transmission you have so it's hard for me to say. Worst comes to worse you could probably just cut and splice your own connector into the existing ckp sensor - it's nothing but a reed sensor that completes/breaks a circuit.

TrojanMan
08-20-2006, 12:22 AM
I have a question about the head you used. If 95HO heads have the best flow and are the best choice for building a stroker, would it make sense if I were to port and polish a 95HO head now, and put it on my 00WJ? I was planning on pulling the head to port and polish and put a header on it this winter, but now I'm thinking I might be better off buying an older 95HO head and working that.

Yeah if you can find one cheap go for a 95HO head. I did the 96 because i've already had a little work done on it and I didn't want to go buy another head.

93_5spd
09-08-2008, 06:05 PM
After 10 months of fiddling around, I finally got my stroker motor up and running. The project hit major stalls due me being in Iraq, but now I'm home and it's finished.

A couple things i found:
Don't waste money on an adjustable Fuel Pressure Regulator when you want 49 PSI from a '95 or older setup. I found a FPR from a 93 Eagle Vision TSI w/3.5L v6, fastory set for 48 PSI. In actuallity, it runs at 46 psi idling with vacum connected, and 54 psi idling with it disconnected. NO PINGING, zero zilch nada. (i however bored it .040 instead of .030, i think that made a difference)

When switching to the 99+ intake manifold, my timing cover was rubbing the belt, and had to be ground off a small bit.

Payclose attention to setting the timing. I used a crower cam, and didn't have to grind off the ears of my dist. If it is installed 180* out, you can swap plug wires around, and it'll run, but be hard to start, be low on power, and suck gas. Follow the directions earlier in this thread, it's amazing what doing it right does for power.

dirty
09-08-2008, 09:54 PM
Payclose attention to setting the timing. I used a crower cam, and didn't have to grind off the ears of my dist. If it is installed 180* out, you can swap plug wires around, and it'll run, but be hard to start, be low on power, and suck gas. Follow the directions earlier in this thread, it's amazing what doing it right does for power.

You cannot time this motor. Get it close and it does it all by itself. Mine ran without grinding the ears off the distributor. It was a bit slow to start. I reveresed it (180 degees), same result. I bought a timing light, ground off the ears, and did a 30 degree sweep off number 1. The engine will change pitch...then the computer will take over and do what it wants. If it runs good be happy, but you are not timing it.

93_5spd
09-08-2008, 11:39 PM
You cannot time this motor. Get it close and it does it all by itself. Mine ran without grinding the ears off the distributor. It was a bit slow to start. I reveresed it (180 degees), same result. I bought a timing light, ground off the ears, and did a 30 degree sweep off number 1. The engine will change pitch...then the computer will take over and do what it wants. If it runs good be happy, but you are not timing it.

I got it to run at first, but found out i had the rotor 180* out. The I used the 3.0 cm distance spec'd in DIno's writeup, put the oil pump @11, turned the rotor about 20* CCW, and droped it in. Lined up perfectly with the mark i made, and was just past the #1 spot on the cap. If you have the ears ground off, you can make it "out of time" as well as if you have the rotor indexed wrong. Maybe i should have said once you get it indexed instead of in time, either way, the jeep has balls!

So far I've got 92 miles on it, loving my jeep again after not driving it since May '07

TrojanMan
09-09-2008, 01:35 AM
I hear you with setting the timing correctly. I set it about 20* out and damn near killed myself for it. Should have just followed directions the first time instead of second guessing myself.

What branch are you with?

dirty
09-09-2008, 04:29 AM
I got it to run at first, but found out i had the rotor 180* out. The I used the 3.0 cm distance spec'd in DIno's writeup, put the oil pump @11, turned the rotor about 20* CCW, and droped it in. Lined up perfectly with the mark i made, and was just past the #1 spot on the cap. If you have the ears ground off, you can make it "out of time" as well as if you have the rotor indexed wrong. Maybe i should have said once you get it indexed instead of in time, either way, the jeep has balls!

So far I've got 92 miles on it, loving my jeep again after not driving it since May '07

Roger. And x2 on the balls...I've never driven anything with so much low end torque.

Arsonist_Bob
01-22-2009, 11:49 PM
just get a 4.7 :D

93_5spd
01-23-2009, 01:21 PM
just get a 4.7 :D

WTF??? You go through the trouble of putting a late model SMALL V8 into my OBDI Jeep. I've got plenty of power, and still pull ~18-19MPG highway with 35's. SO much power in fact, I snapped the output shaft on my tcase, twisted the slipyoke on the driveshaft, broke my carrier, exploded the spider gears, and chipped the pinion gear. Just from a 3k RPM launch trying to 'showoff' on dry pavement when a Mustang decided he wanted to race the heavy jeep with the stroker badge. (2000 8.8 ford axle)

Keep your 4.7 and the WJ it's wrapped in. :finga: Unless you've driven one, the low end and midrange torque of a stroked I6 can not fully be appreciated. It's already cost me $800 in broken driveline parts. We'll see how the ax15 holds up!

TrojanMan
07-09-2009, 02:42 PM
Sure, but you pay for the pistons and bore at the machine shop.

I do hope you're talking about a 4.6 variant.

rob92xj
08-02-2009, 01:15 PM
Finally got my 4.7L done this year it is awesome. I just need to get the right injectors for it so I have been taking it easy and running 93 octane. Low end torque is great.

I used a 96 NVH block, 89 4.2L crank and rods from a friends Wrangler, .060 over Speed Pro pistons and rings Competition Cams Extreme 4x4 cam, ported and polished head, cc'd chambers, 99 WJ intake ported to match the head.
http://photos-e.ak.fbcdn.net/photos-ak-snc1/v2645/181/73/1408891098/n1408891098_276324_7920548.jpg

The old 4.0L next to the 4.7L
http://photos-g.ak.fbcdn.net/photos-ak-snc1/v2645/181/73/1408891098/n1408891098_275358_4980401.jpg