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Moses Ludel

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Everything posted by Moses Ludel

  1. Stuart...This is just what I envisioned for your end result: a great venue to enjoy that CJ-7! The Jeep looks terrific, the terrain does, too...In answer to your questions:
  2. Wow, Speed, ambitious projects for winter time at Elko. Sounds like your distributor swap will do the trick on the Toyota. Good that NAPA had a replacement/rebuilt module. The National Cowboy Poetry Gathering is on this week at your town. That certainly raises the traffic count! Glad you're there for your sister, Speed... Moses
  3. Monty...Your modern gear lube is a better product than lube available when this winch was new. As for the lifespan of a Koenig PTO winch in good condition, you have a winner! Koenig's Texas base was a hint about its primary market: oil field trucks and industrial applications. This was not a recreational market, and commercial usage demanded efficiency and reliability. Hoisting equipment was another market, and Koenig winches were often seen on wreckers and tow trucks. Ramsey and Koenig competed with each other for this commercial market, and each became popular in the emerging recreational markets. Koenig had a firm market in oilfield work, mining, mineral exploration, hoisting and industrial winches. Yes, you have an "industrial strength" winch, and PTO power is the ultimate torque source with gearing—as long as the engine is not stalled while stream fording or scaling a rock wall. Here, an electric winch prevails. Moses
  4. Additional exchange with Lynn: Question from Lynn: "I am hoping this is the last time I’m bothering you about pinion angles. Thanks again for the in depth explanations...I downloaded an app to measure angles a little more accurately. I came up with 13.5° on driveshaft and 8.5° on pinion yoke. So does that work out to be a 3° shim I need? Also I believe when shims are installed on CV driveshaft the beefy end will be facing the rear of Jeep?" Lynn...Your measurements must be with the vehicle on level ground and the body's weight fully on the axles…If you measured the pinion yoke at the flange flat (with the yoke flanges pointed straight up and down), then the pinion shaft is on an 8.5-degree slope or angle. If the pinion shaft is on an 8.5 degree slope, and the driveshaft is on a 13.5-degree slope angle, the difference between the two angles is 5 degrees. You want to reduce this difference to 1.5 to 2 degrees. Rotating the axle housing and pinion shaft upward with a three degree shim set should work. The end result will be 2-degrees of U-joint tilt or angle. Most shims, by design, allow minor adjustment in either direction, but 2 degrees is fine. I run 2-degrees on my XJ's rear U-joint angle. When you are through installing the shims, with the spring U-bolts torqued evenly to specification and the Jeep on level ground with body weight on the axles, you should have a 2-degree or less rear U-joint angle or tilt. The driveshaft slope angle may decrease slightly when the pinion rotates upward, dropping the difference figure closer to 1.5 degrees. Let us know your final readings. The "shims" are wedge-shaped metal plates that fit between the axle perches and the leaf springs on your Jeep XJ Cherokee. (The TJ and newer Wranglers have link-and-coil spring suspension, and the shim fit is different.) You will be raising the vehicle safely, supporting the body/frame, allowing the springs to sag fully, and then loosening the spring U-bolts evenly. When there is enough gap between the spring centering bolt and the axle spring perch to allow inserting the wedge shim, the shim's narrow end will face forward. When both shims are in place, the tapered shims rotate the axle housing and pinion shaft upward to reduce the U-joint angle...Shims are not installed on the CV driveshaft itself; the tapered shims fit between the axle spring perches and leaf springs to rotate the axle housing and pinion shaft. This rotation changes the pinion angle. I use steel (not aluminum) shims that match the width of the leaf springs. Shims need to support the leaf springs properly. Torque the spring U-bolt nuts in cross and evenly to factory torque specification. I like to re-check the nut torque after driving the vehicle and cycling the suspension. Moses
  5. Lynn shared this photo. Here, he has only measured the driveshaft slope...Below the photo is my explanation of how to measure the driveshaft-to-pinion shaft (U-joint tilt) angle: Lynn...I looked closer at your photo and saw the string measurement. This must be your driveshaft (tube) slope with the vehicle level. The measurement you want is the angle between the driveshaft (tube) and the axle pinion shaft. If you draw a line straight out from the pinion shaft centerline and measure its relationship to the driveline slope, you have the angle you want. Put simpler, you can place your string gauge on the flat outer flange of the pinion yoke with the pinion/U-joint yoke facing straight up and down. Note: For pinion angle reference, the axle’s pinion shaft centerline is parallel to the pinion yoke’s outer flanges. The magnetic angle gauges attach to the U-joint yoke’s outer flange(s). It is important that the U-joint yoke’s flanges face straight up and down when measuring this angle. The 1.5 to 2 degrees is the angle or tilt of the rear U-joint. If your driveline slope with a string line gauge is 20 degrees, the axle’s pinion centerline angle should be 18.5 to 18 degrees. (In geometry or trigonometry, the angle between the driveline tube and pinion shaft centerline is two intersecting slope lines with a deviation of 1.5 to 2 degrees.) With the CV driveline, the axle’s pinion yoke joint angle approaches a straight line with the driveshaft tube, deviating only 1.5 to 2 degrees from straight. That tilt has the axle pinion shaft pointed slightly downward. The usual tools for measuring this angle would be a protractor gauge or a magnetic spirit/bubble level gauge. Both measure in degrees like your string gauge and plumb bob. Your approach can work if you use the gauge and plumb bob/string properly. When the axle housing is rotated correctly, the driveshaft tube will appear to run nearly straight into the pinion, the tilt being only the slight 1.5 to 2 degrees. Below is a factory/Mopar Inclinometer (7663) tool for measuring U-joint flange angles and, in this instance, the front axle caster angle. This gauge has a spirit/bubble and a tilt scale in degrees. The top of the gauge has a magnet that attaches to a U-joint yoke flange: Here is a time-honored Spicer Anglemaster gauge, the latest "Anglemaster II" version. Note that this gauge attaches on the flatly machined flange end of the U-joint yoke. This angle can be quickly compared to the slope angle of the driveshaft. The difference between the two angles is the U-joint tilt or joint angle. These angles are always measured with the vehicle at normal/curb ride height and vehicle weight on the axle(s). Do not take driveline and joint angle measurements with the axle hanging off the floor. The vehicle should be standing on level ground or with the axle(s) supported safely on jack stands or tripod stands. Driveline angles for trucks or SUVs that carry a hefty load should be measured with the full payload on the axles: For more information on an SYE conversion and the use of a CV rear driveshaft, visit: 4WD Mechanix Magazine article on an NP/NV231 transfer case SYE kit installation, click here. For details on our XJ Cherokee's 6-inch long arm lift that required an SYE and CV rear driveline, click here for the magazine article at 4WD Mechanix.
  6. Speed, I have a suggestion for a 1978-87 Toyota pickup service manual that you would find very helpful: Toyota Pickup, 4Runner Service Manual by Robert Bentley Publisher. Bentley is my book publisher, and they do the factory shop manuals for VW North America and Porsche, very professional, detailed stuff. My Toyota Truck and Land Cruiser Owner's Bible is in the Bentley Publishers book stable, but in this case I'm referring to an earlier Bentley in-house book that was model year specific and a designated shop/repair manual. The Toyota Pickup, 4Runner Service Manual is no longer in print and would need to be found and purchased used at Amazon, eBay or from an automotive literature (used books) outlet. Here's an earlier printing (through 1984 models) at Amazon: https://www.amazon.com/Toyota-Pickup-Truck-Service-Manual/dp/0837602521/ref=sr_1_fkmr1_1?keywords=Toyota+Pickup%2C+4Runner+SErvice+Manual+Robert+Bentley&qid=1577800801&s=books&sr=8-1-fkmr1 If you can find a copy of Bentley's Toyota Pickup, 4Runner Service Manual on eBay or through used book channels, it has far more detail and helpful content than Haynes or any other aftermarket book. In the "Brakes and Wheels" Chapter 8, Pages 7-10 of the 1978-87 edition, there is a section devoted to your truck's Load-Sensing Proportioning System, including useful illustrations of the parts relationships and their original shapes. Equipped with a quality shop manual (either the book I'm suggesting or an official Toyota FSM that covers your truck), your confidence would soar. Unfortunately, many shops do not follow these protocols and either do not have the right books or have functionally illiterate, "know-it-all" staff. Social media like YouTube has gone further to dumb down and trivialize automotive work. Better training standards, brake work certification tests (like the trucking industry) and pay incentives would be helpful in this country. NIASE is a step in that direction but does not train techs to work on specific vehicles, model types or unique brake devices like your Toyota load-sensing rear brake proportioning system. I have bookcases full of FSMs from the 1940s to present and general automotive trade books dating back to the 1920s. Despite 52 years of professional automotive work, I still rely upon factory-level shop procedures and protocols. Anyone who doesn't is not performing professional grade work. If you cannot find or afford a used copy of the Toyota Pickup, 4Runner Service Manual, let me know. I'll scan the four pages described from the copy setting in my bookcase and post as a PDF. My publisher will not be offended nor cite me for infringing on copyright, the book is no longer in the market. Moses
  7. When installing a CV or SYE rear driveline, the rear axle pinion angle is important. A Jeep XJ Cherokee owner asked me about this angle and axle shimming (changing the pinion shaft angle). Here is our exchange: XJ Cherokee Owner's Question: "Mr. Ludel...I am wondering if you have an SYE on your XJ? I had one put on with a Tom Woods driveshaft. [The Jeep] rides smoother with its 2 1/2” lift, but I did not install shims. Are shims a must with an SYE?...Lynn W." My reply: Hi, Lynn…An SYE driveshaft has a double-Cardan or CV front joint. A double-Cardan joint has self-cancelling angles. The angle at the pinion/axle end of the rear driveshaft is important, however. That angle with an SYE/CV driveshaft should be 1.5 to 2-degrees. This is measured with the vehicle on the ground or the axles weighted. If the rear joint is straight (0-degrees), there will be inadequate rotation of the needle bearings inside the U-joint. The joint will fail prematurely…Too much rear U-joint angle is not good either. So, to answer your question, you do want to shim/rotate the rear axle and pinion shaft to achieve a 1.5 to 2-degree rear U-joint angle. I use hard steel (not aluminum) shims...Moses Here are Lynn's photos...This shaft needs a rear U-joint angle adjustment: Lynn's SYE and CV driveshaft has a Double-Cardan front joint...Here, the double U-joints cancel each other's angles... Lynn's rear axle pinion joint angle needs to be corrected. This single Cardan joint should run at 1.5 to 2 degrees, set with the vehicle's weight on the axles...To correct the pinion angle, wedge shaped shims fit between the rear axle's spring perches and the leaf springs. Pinion/U-joint angle is corrected with these shims.
  8. Hi, Speed, have a safe and pleasant New Year...Best in 2020...See my comments below:
  9. Let us know how this works out, Monty. What lube will you use in the unit? What did Koenig recommend?
  10. Monty...As a guess, the "KT88" bearing is likely a Timken T88. The "K" could be for "Koenig" parts inventory replacement purposes. Below is an illustration of the T88 Timken bearing. Does this look like a match? If this is it, the number is current, and retail price has it at $10-$15 from a variety of sources. I've added two part numbers that Timken still uses. The links are live and go to Motion Industries. If you can confirm the bearing fit (see sizes), the bearing is available from any Timken source. There is a small image below the larger one that may be helpful. Moses Timken T88W-904A3 Tapered Roller Thrust Bearing - 0.885 in Bore, 1.8906 in OD, 0.594 in Width Timken T88-904A1 Tapered Roller Thrust Bearing - 0.885 in Bore, 1.8906 in OD, 0.594 in Width
  11. Hi, Monty...What is your winch type, make and model? I'll check for a parts schematic that shows the orientation of these parts. The shown pieces appear to be in good shape! Vintage quality...Compare this to contemporary winches. Season's Best! Moses
  12. Wow, Stuart, the long and winding road! Years ago, Arizona required a simple tailpipe reading for emissions and never opened the hood. That changed, as you hint, to match California and other states where a visual inspection of emissions equipment is a mandatory part of emissions tests. Maybe there is a model year cutoff for the full inspection test, and if old enough, a vehicle reverts to the older tailpipe reading only method? Or does this have to do with your zip code? Pleased that you're on the road. This must be gratifying. The high HC/CO readings with your original carburetor could have reflected a unit with the wrong jetting. You were meticulous in your approach to rebuilding the carburetor, it should have performed to OEM standards. (The old carburetor may not have been in original form.) In any case, the El Monte shop's build must have the right jet and metering rod. Keep us posted on the performance and your driving impressions. Yes, the CJ-7 is a great improvement over the vintage Jeep CJ3B chassis, worlds apart. You have a longer wheelbase (94" versus 80") to smooth out the washboard roads plus longer springs to improve ride quality and control. I like an aftermarket front spring/shackle reverse on any of the Jeep models through the YJ Wrangler. Vehicle control and steering improve, and there's less frame impact when climbing over rocks or limbs. The front axle trails instead of being pushed forward from the anchor (rear) end of the front springs. Something to consider, not a must. Where will you be driving off-road at Arizona? You have a wealth of open country to explore! Season's Best, Moses
  13. The Clark slipping out of 5th does sound like worn bearings, most likely at the nose end of the main/output shaft. This is the pilot bore bearing (not to be confused with the crankshaft/input shaft pilot bearing) that keeps the main shaft aligned. End bearings are likely worn, too. (A worn crankshaft pilot can cause jumping out of the other gears.) Bearings are not that expensive if you want to tackle this rebuild yourself. The bearing set, seals and making gaskets for a Clark would be less costly than a core/used SM465...As for noise, much if it is harmonic and inherent to spur gear transmissions.
  14. That's what I thought...I serviced a period I-H RD406 powered dump truck in the late 'sixties that had your box. It was a double-clutch, straight cut gear (non-synchromesh) Clark. These units are bulletproof but do require a savvy driver, of which there are few in this era. Yes, it would make the ultimate transmission for some applications but would weigh too much and require a divorced transfer case in a 4x4. There is no room for such a transmission and divorced transfer case on a shorter wheelbase 4x4. Doubt that's the market for an iron Clark 5-speed. Why don't you want to run the Clark? It's a somewhat rare bird in vintage Advance Design GMC trucks, the SM420 4-speed was common.
  15. So, the Clark has synchromesh on 2-3-4-5 (overdrive)? Compound first gear is the only gear without synchros? I would think this would be desirable, although the overdrive is light at 16%. Synchro changeout seems cheaper than a good used SM465, which might also need synchronizer rings and and bearings. Your motive for the SM465?
  16. Speed...Glad you're aware of the PSI limit for the Weber. It's even lower than I thought, good that you have the specification of 3.5 PSI maximum. If the stock fuel pump puts out too much pressure, there are inline pressure regulators that can be manually adjusted to the desired pressure. This has been the time-honored way to damp down pressure on these Weber installations. On Jeep CJ/YJ 4.2L engines, the AMC inline six fuel pump is in the 6-7 PSI range, which can wreak havoc on a Weber float and needle. If pressure is too high, a Weber will over-fuel the engine. Sounds like you have a vacuum leak, maybe a good one. When backing the throttle stop screw out completely, if the engine continues to run fast, that's a sign of air entering the A/F stream from somewhere. If not a vacuum leak, you may be pushing too much fuel due to excessive fuel pump pressure as we've discussed. Check the fuel pump pressure. Check for a vacuum/air leak. A simple approach is a can of WD-40 or a similar low volatility petroleum base spray cleaner. (Avoid hot areas like the exhaust manifold!) Spray a light mist around the carburetor base, the intake manifold junction with the head and the vacuum hoses. Engine speed changes indicate a leak...Cap off or plug vacuum lines if you suspect a vacuum hose or device leak. See whether that helps identify the leak(s)...Even the brake booster can create a vacuum leak, often a big one if the diaphragm or check valve bleed off. Moses
  17. An Allison transmission? The 4L80E four-speed (OD) was typically used in the '90s unless his truck is either heavy duty or has a transmission swap. Wiring will be his bigger challenge, overlaying the chassis wiring schematics to compare the differences then splicing or swapping harnesses.
  18. About right on the custom driveline construction cost. Joints are also spendy for medium duty trucks. $125-$150 for shaft work like this was a norm for years. Shop labor is floating around $100-$125 per hour at Reno. $250 is 2-2.5 hours.
  19. Innovative approaches...The Weber is altitude sensitive and generally needs jetting for the altitude/locale. Another issue is float/seat pressure. Keep fuel pump pressure within the limits for the Weber, usually 4 to 4.5 psi or so. Look up the specs for your particular Weber series. Flooding will result otherwise.
  20. He's not losing much by getting rid of the 6.2L/6.5L GM diesel. The turbo 6.5L version was okay, naturally aspirated they were not impressive. We had a mid-'90s Suburban 2500 test vehicle with this engine; the 6.5L had a stronger lower block assembly and turbocharging, it ran quite well, made enough noise and got marginal fuel economy. The gas engine is probably a match for fuel efficiency.
  21. I like the SM465 for its tough torque capacity and robust iron case. The compound gear is very low (almost like the SM420). This unit was a natural behind a 383 SB Chevy stroker conversion in a Landcruiser. Major gear reduction! A wise choice for the '54 GMC and not a difficult fitup...
  22. The owner of a 1998 Jeep Wrangler had several questions about the use of a CompCams 252H grind camshaft in a Jeep 4.6L stroker inline six engine build. His engine core is a 1998 Jeep TJ Wrangler 4.0L...Here is our exchange. My comments are in red: Keith M.: I’ve seen some posts, including on Comp Cams’ site, that say the head on the ’98 has different size valve stems than other years and that cams that will work on other years won’t work on this one. I’m pretty confused by what seems to be conflicting and unreliable information. Moses: I’m not clear why there is so much confusion. CompCams should know parts interchangeability and sizing. 4.0L valve stems are available in both standard size and oversize for a given engine, which may account for the confusion. Parts interchangeability spans many years. Exhaust or intake valve head diameters may change while stem diameters remain common. Federal-Mogul is a well-known reman engine industry parts supplier. We’ll use F-M as a reference source: https://www.fme-cat.com/overlays/part-detail.aspx?brand=SP&PartNumber=V-2527&pt=Intake%20Valve&lu=1998%20JEEP%20WRANGLER&vin= [Intake valves] https://www.fme-cat.com/overlays/part-detail.aspx?brand=SP&PartNumber=V-4554&pt=Exhaust%20Valve&lu=1998%20JEEP%20WRANGLER&vin= [Exhaust valves] https://www.fme-cat.com/Application.aspx?year=1998&make=JEEP&model=WRANGLER&cat=Engine&engbase=4.0L%20L6%20242cid&ga=Y&back=true [Overview of intake and exhaust valves] https://www.fme-cat.com/overlays/part-detail.aspx?brand=SP&PartNumber=VK-216&pt=Valve%20Spring%20Retainer%20Keeper&lu=1998%20JEEP%20WRANGLER&vin= [Valve retainer keepers] https://www.fme-cat.com/overlays/part-detail.aspx?brand=SP&PartNumber=HT-2011&pt=Valve%20Lifter&lu=1998%20JEEP%20WRANGLER&vin= [Lifters are the same over all inline Jeep/AMC sixes] A concern with camshaft installations would be the rocker arm ratio. See the rocker arm interchangeability in this listing. AMC/Jeep inline six rocker arms are essentially the same with the same ratio: https://www.fme-cat.com/overlays/part-detail.aspx?brand=SP&PartNumber=R-905A&pt=Rocker%20Arm&lu=1998%20JEEP%20WRANGLER&vin= Pushrods for 4.0L engines fit the full range of 4.0L years. They are available in different lengths because the rocker arms are non-adjustable. I have discussed this at length in the forums and magazine; see https://forums.4wdmechanix.com/topic/1155-42l-re-build-77-cj-7-project/ and my reply comments from December 25, 2018 and forward. Read the details on fitting the right length pushrods. Here is the F-M parts listing for 4.0L pushrods in a standard (OEM baseline) length. There is selective fit application coverage to compensate for engine block and cylinder head deck height changes, head gasket thickness and so forth: https://www.fme-cat.com/overlays/part-detail.aspx?brand=SP&PartNumber=RP-3275&pt=Push%20Rod&lu=1998%20JEEP%20WRANGLER&vin= Keith M.: I want to use the 252 cam you recommend in your video but I haven’t been able to find a video with specific part numbers. Some of the information I’ve seen indicates that I need to change the valve springs if I go to that cam, other places I don’t see that. I need a timing set but have new lifters so I’m trying to get a package if I can but don’t want un-needed parts. I’m also unsure of which cam works with fuel injection as I have been told this makes a difference. Moses: Sounds like you just need the 252H camshaft if your new lifter set is compatible. If the lifters are OEM replacement, ask CompCams tech if OEM lifters will work with the 252H camshaft. Typically, the camshaft kit includes the cam and lifters, but if CompCam simply uses an OEM replacement type lifter, you could save some here. The 1998 4.0L upper valve train (valves, retainers, keepers, rocker arms and such) should be readily compatible with your 252H camshaft choice. You do need to use the correct length pushrods to attain the right lifter preload as described at the forum exchange and magazine articles. If lifters are the same, you can see whether CompCams is willing to sell the camshaft by itself. They may not warrant the camshaft if you don’t use their lifters…Always use engine break-in lube additive (Lucas, CompCams, etc.) with ZDDP to assure proper seating of the lifters with the camshaft lobes. You still need a timing set from whatever source plus correct length pushrods if the OEM pushrods are not the correct length. As for the PCM compatibility, there is the issue of Coil-On-Plug engines requiring a different camshaft than the 252H. Your engine is not C-O-P, it has a distributor and earlier PCM programming. I’ve not heard of anyone getting an engine code from a 252H camshaft installed in a pre-C-O-P engine like yours. If I were to build my 4.0L 1999 XJ Cherokee distributor type engine into a stroker, I would use the 252H grind camshaft rather than use a stock OEM replacement. I have used the 252H grind with EFI truck engines as far back as a Ford 300 inline six MPI engine (1987). The 252H grind has also been tested repeatedly by Tony Hewes on pre-C-O-P EFI/MPI 4.6L stroker builds. Keith M.: This package would be fine, under specifications it says it works on years 1964-1998. But I can’t be sure that’s correct really, because of the fuel injection and possible valve stem issue: https://www.compcams.com/high-energy-206-206-hydraulic-flat-cam-sk-kit-for-amc-199-258-4-0l.html If I had to replace valve springs I’d use this kit: https://www.compcams.com/high-energy-206-206-hydraulic-flat-cam-k-kit-for-amc-199-258-4-0l.html In specifications it says 1964-1998, but under Installation Notes it states ‘K-Kits will only work in 1964-88 models due to different valve stem diameters” Moses: Valve springs and retainer sizes are governed by the valve stem diameter. This appears to be the reference here. Logically, you do need to match valve springs and retainers to the valve stems and cylinder head spring seats. For your purposes, you only need to use the right diameter 4.0L valves, matching springs and retainers for your cylinder head casting and model year choice. Approach the valvetrain like you’re rebuilding a stock 4.0L engine. Choose replacement parts for the cylinder head casting and block casting involved. Keith M.: And somewhere in here there’s a review for a kit where the reviewer states the kit won’t work specifically on the 1998 engine. That’s strange to me and seems incorrect- I have two heads, one is a 7120 of an earlier (1991-1995 I think) and then there’s the 0630 casting that came off my 1998. Both have 5/16 valve stem diameters by my measurement so I don’t believe there’s a difference. I’m assuming the whole problem with valve stem diameter is the earlier years are a different size so the later heads won’t work with the keepers and other valve spring parts that come in the kit. Moses: My assumption, too. We’re in accord here… Keith M.: I’m just trying to avoid getting the wrong cam and having it fitted to the bearings and then having to get another one. I don’t want to reuse the stock cam really, but I don’t know enough to say a different cam is worth it. This Jeep needs to idle and drive well on the street, I can’t have it be stumbly or rough idling as I will be selling it at some point soon. I do want to learn how to do these builds well as I restore IH Scouts- the 4.2 was an available engine that I think is much better in many ways than the IH engines and if I could find a way to build an excellent and reliable stroker with a 4.0 block and the 4.2 crank I’d do these regularly. Moses: Understood, Keith…I’m a Scout buff, too. If fuel efficiency is an aim and vehicle weight not excessive, a 4.6L build from a 1991-99 (pre-C-O-P) 4.0L block and head could make sense as an alternative to the 304 or 345 I-H V-8. I-H was wise to outsource AMC 4.2L/258 engines, they offered a high-torque design that tolerated emission controls better than competitors. Keith M: Thanks for your help Moses, I’ve done my best to sift through all the info out there and I just can’t come to the right conclusion without your advice...Respectfully, Keith M. Moses: No problem…You want to build a safe and reliable engine. My recommendation for the 252H grind has always been simple: This grind offers increased lift with moderate duration. More lift without increased duration means a “bottom-end” camshaft that actually enhances the idle, tip-in response and mid-range power. This cam is much different than the 260H grind. Since the 1980s, I have recommended the CompCams 252H for fuel efficiency, quicker torque rise (more diesel-like), superior idle and rock crawling tip-in stability. This camshaft raises idle vacuum and maintains higher manifold vacuum from idle to mid-range rpm. This is simply a trailer pulling, rock crawling, high manifold vacuum camshaft for optimal power at low speeds, midrange and to a realistic 4500-5000 rpm maximum shift point. It will make power to 5,500 rpm in a pinch. In your 1998-based pre-C-O-P PCM engine, you should experience no problems. The lift is not extreme and will not create valve spring “coil bind” with stock ratio rocker arms. (Valve springs must be new or in good condition and provide the proper spring rates at specified valve spring heights.) With a stroker crankshaft, the 252H makes even more “stump-pulling” sense. The gearing of your Jeep should target a 4500-5000 rpm maximum engine speed. Your single rail EFI/MPI, the 1998 PCM, MAP sensor and camshaft sensor will find this camshaft compatible. The 302 Ford V-8 injectors described in my articles will make sense. C-O-P engine builders should consider the newer grind from CompCams to avoid engine check light issues. The C-O-P PCM and camshaft position sensor monitors the OEM camshaft valve opening/closing events (lobe valve timing). The CompCams 252H valve opening/closing events can trigger an engine check light on a C-O-P engine with its PCM programming. A roller chain (Cloyes or similar) timing set is always an improvement, though the 252H camshaft will work with a stock/OEM replacement set as well. Your focus should be selecting the correct length pushrods and setting the valve timing to factory marks. This is optimal valve timing for the performance gains I have described…Make sure you install the distributor correctly, which will properly index the camshaft position sensor and ignition rotor in the process. There is nothing exotic about the 252H grind. I have installed this camshaft as an OEM replacement. The valve/lobe timing creates an issue with the C-O-P engines because the later PCM is looking for specific valve opening and closing events in relationship to the crankshaft. Let us know how your 4.6L build turns out and your impressions of the 252H camshaft performance... Regards, Moses
  23. Yea, Stuart! Sounds like you nailed it...This will be a great engine. Smart to use Lucas break-in oil with ZDDP. The camshaft lobes-to-lifter bases represent the highest friction point per square inch in the engine. Proper break-in will deliver many, many years of quality service! Congrats on a job well done... Moses
  24. Really nice work, Stuart...Attention to details is impressive, especially the emissions components. You should have the tune ironed out shortly, just in time for fall hunting! Reliability will be high for this 4.2L engine. The DUI ignition is a great upgrade. If you need a sounding board for any fire-up issues, I'm here...Awaiting your first impressions of the "new" CJ Jeep! Moses
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