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Moses Ludel

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  1. Really good and realistic fuel mileage, Bill W.!!! Lots of 6% grades on your trip. My software tune may not be 50-State, so look into that before plunging. While performance gains have been noticeable, the promise of improved fuel efficiency has never been realized; however, as I share, my truck has "great looks" and terrible aerodynamics with lots of add-on accessories weight. My one and only 25 mpg stint (during 500 miles from Fernley, Nevada to Portland, Oregon) was with a stone stock truck, no tune software, no lift or oversized tires, no added accessory weight, no TransferFlow auxiliary fuel tank, and no beefy Warn winch bumper. Today, 20 mpg at interstate speed is realizable if I hold rpm to a ceiling of 1,800 rpm with my axle gearing at 4.56, 37" diameter tires and 31% overdrive (48RE automatic in 4th gear). During the Portland trip, the original 3.73 gears were in place with stock 265 tires (31.9" diameter) when I pulled off the 25 mpg. I ran the entire distance between 1,600-1,900 rpm and stayed as close to 1,600 rpm as practical. I allowed light throttle automatic upshifts at 1,100-1,400 rpm. The rpm peak/ceiling was 1,900 rpm for the entire trip. 1,600 rpm provided the peak mileage. Watching for your additional comments...Glad you enjoyed the trip! Moses
  2. Hi, Bill W....I'm following your mileage tracking with great interest! Your trip involves summits and 6% grades, even steeper to Virginia City. This is certainly not a flat ground test. We have family at Virginia City and enjoy the area. Tahoe should be at winter best...You will have a great time, the weather this weekend and early this week is exceptional for March at the Reno/Tahoe Area, higher day temperatures in the mid-60s this weekend after the heavy snowstorms. Virginia City will require jackets! Moses
  3. retiredfire...A 1904 has the application part number stamped into the main body just inboard of the float bowl cover near the fuel inlet. The stamping should be at the top, right next to the bowl cover on that casting flange. See whether you can find a number. I can verify if the carburetor(s) are original or from other engine applications. As for the check ball(s), I can provide a detailed parts schematic for the 1904 that would clarify here. A quality rebuild kit will have instructions with a parts diagram as well. I have a Holley Master Catalog that covers postwar through the early eighties. I can furnish OEM stamping numbers for a 152. A typical Scout 152 carburetor number would be something like "R-2494A" or "R-2494AAS". Let me know the stamping numbers on the two carburetors. We can go from there. If you need a parts schematic for the check ball issue, let me know...Moses
  4. retiredfire...See my comments in red below. Let me know if that helps...Moses
  5. Carib Snake...Greetings. I can see your dilemma and can answer a few of your needs, others can add to that. See my comments below in red:
  6. Zeke Cheek...Can you shift into the other gears without a problem? When shifted into one of the other gears, does the clutch pedal come off the floor some before it starts to engage? Is the clutch disengaging completely? If not the clutch, check out my video, it's been helpful as a step-by-step guide for teardown, inspection, checking tolerances and proper assembly of an AX15: https://4wdmechanix.com/rebuilding-the-jeep-or-dodge-dakota-aisin-ax15-and-toyota-150-151-and-154-series-transmissions/ Watch the video and see if you catch something that might have been missed during your assembly work. If the transmission shifted well after assembly then stopped shifting into 2nd and 4th as you describe, it could be either clutch disengagement or something misaligned. This could include loose transmission to bellhousing or bellhousing to block bolts, a binding pilot bearing in the crankshaft or loose internals in the transmission. Before diving into those issues, see whether the floor shifter boot is preventing the shifter from moving far enough into 2nd and 4th. That issue is common with lift kits that lower the skid plate/transfer case. Moses
  7. GlenH...Sounds good and thorough, too. Your method and testing should be helpful to other Dauntless V6 225 owners. Thanks for the link and follow-up! Moses
  8. GlenH...A 1/64" hole, if adequate lubrication, would not be an issue. Bleed-off would be minimal if this is a proven method. Worth a try? If the camshaft and lifters appear "normal" with no wear indicated, I would replace the button and spring just as a precaution...Be aware that production Buick V6 engines have one bank of lobes ground with a slight taper in one direction; the opposite bank is ground with a slight taper in the opposite direction. (Lifters have a convex base, so the taper is not an issue.) This centers the camshaft in service. Aftermarket cam grinders often ignore this measure and grind the lobes without a taper. This allows the camshaft to thrust forward with more pressure. Check the lobes for front and rear facing taper. A footnote: In building Buick V6s for racing, an aftermarket needle bearing thrust button assembly was often installed. A plate was installed at the backside of the timing cover to serve as a mating/wear surface for the needle bearing thrust button. The clearance and fit between the thrust button and stop plate had to be carefully determined...This was the allowable camshaft thrust forward. It's easier to use a button and spring if the camshaft lobes were ground correctly with opposing tapers. I've not had issues with the Melling K-20IHV kit. Again, gear and plate alignment is crucial. (The kit comes with two alignment roll pins and assembly spacer shims to center the gears and spacer plate.) Choice of the correct pressure relief spring is also critical. The aim is not to increase oil pressure. This pump kit assures adequate volume. If the pressure is boosted too high by using the wrong spring, the result will be a heavier load on the distributor drive gear pin. Although oil viscosity plays a role here, too, I'm guessing that nearly all owners run a multi-vis. A stiffer straight weight oil with slow pour in cold weather could conceivably put excess load on the distributor drive gear pin. My guess, though, is that sheared pins are likely from too much pressure, enhanced by the longer gears. Summit Racing (see link below) has a photo of the complete kit. Note the shim stock, two roll pins, a variety of springs and the gear tooth lengths: not extreme, just enough to raise volume. When selecting the right oil pressure spring, the factory setting for a stock 225 Buick/Jeep V6 is 33 psi at 2,400 rpm with the engine warmed. That's not a lot. With stock bearing clearances, 40 psi at 2,400 rpm would be plenty. (This is not an AMC inline six or small-block Chevy V8!) These engines need adequate oil volume, not excessive pressure. Anyway, I'm not trying to sell anyone on the idea of this Melling high volume pump kit. However, it's been in the aftermarket for many decades with successful installations, mine included. Check out these links: https://www.ebay.com/itm/253006482096 [The marketer has shared the installation instructions. This is a busy pump kit to set up properly. Center the plate when indexing/drilling for the roll pins. Use the correct pressure relief spring and an accurate oil pressure gauge to set the oil pressure at 2,400 rpm. Testing the pressure and picking the right spring are the extra steps that can make a difference.] Current best price and ready availability at: https://www.summitracing.com/parts/mel-k-20ihv Keep us posted... Moses
  9. GlenH...The button pressure is important. Are the camshaft lobes okay? Is there excessive forward thrust of the camshaft that is overcoming the spring pressure? Or is the button spring weak? I've not done the oil feed modification but understand the premise. If the hole size can be determined before drilling, that could be a solution. I have always done the Melling High Volume oil pump modification/kit, which essentially extends the length of the pump rotors/gears and uses a spacer to increase the depth of oil pump gear cavities. That kit would assure plenty of oil volume if you do the modification described. When installing the Melling kit, be certain to align the machined spacer plate precisely before drilling/indexing for the included alignment roll pins (2). (The shims in the kit are for temporary use only while centering the spacer plate with the new gears.) This positioning is critical for the pump gears to run on center and not damage the kit's metal spacer, the new oil pump gears or the timing cover bores. Let us know more about the orifice size for the drilled passage and so forth. This would be a direct bleed but not much different than the rocker arms. With enough pump volume and the correct orifice size, there should be no issue. Moses
  10. Hi, GlenH...I understand your dilemma and frustration...There is a reference within the Jeep (i.e. Buick) description of 225 Dauntless V6 oiling: "The timing chain is lubricated by splash of an oil stream from which oil is directed to the distributor drive gear from the fuel pump eccentric on the camshaft." I emphasized the fuel pump eccentric's role. If the eccentric is either not in place, is incorrect for a 225 V6 or is altogether missing, that could be an issue. The eccentric plays a role for both the distributor drive gear and chain lubrication. Check this closely and get back. Did an engine builder or owner remove the eccentric and install an aftermarket electric fuel pump? Is this the wrong eccentric and not for a 225? The eccentric could affect both the chain lubrication and failure of the distributor drive gear and driven gear. Moses
  11. pesilfven...Your photos of the install will be helpful to others. This is an unusual project with the 258 intake, Howell EFI and the 4.0L cylinder head. Make sure you have good intake port alignment/match-up. You're essentially creating a CA E.O. install with a 4.0L long block engine. This will be interesting for others to see! The Howell system should make a noticeable difference in performance, electronic altitude corrections (with the 02 sensor feedback) and improved fuel efficiency. TBI is good for low end torque, and that's your CJ's realm. Have a pleasant Holiday Season and keep us posted... Moses
  12. pesilfven...Do you need to do an emissions inspection? Does this system have a California E.O. number? Beyond that, I've not installed a 4.2L manifold on a 4.0L head. The Mopar EFI conversion went the other way: A 4.0L ('95 YJ Wrangler prototype) intake manifold was fitted to the 4.2L. The Sniper and MSD Atomic have been around for some time. We followed an Atomic EFI retrofit to a 4.2L at the magazine several years ago. Again, no E.O. number, but it worked and had a clean tailpipe reading. The Atomic EFI was adapted to a stock 1989 4.2L BBD manifold: https://4wdmechanix.com/?s=Atomic+EFI. This is a 4-part series, detailed, that will walk you through some of the obstacles overcome. We took the vehicle over the Rubicon Trail (also covered at the magazine). However, despite the clean tailpipe that met low emissions, the system was abandoned due to lack of a California E.O. number. The YJ's owner subsequently installed a complete 1991-95 era 4.0L MPI/EFI donor engine with PCM and peripherals. He passed California smog as a legal engine conversion...It all depends on your aims and emissions requirements. Moses
  13. Mike S...Howell TBI has been the historic go-to solution. Howell received a California E.O. Number decades ago. At that time, the Mopar MPI/EFI Conversion was the only 50-State legal system and somewhat affordable. The Mopar system is patterned after the 1994-95 Wrangler YJ 4.0L components. Howell's conversion is built around 4.3L GM V-6 components. In 2015, we experimented with MSD Atomic EFI on a YJ Wrangler 4.2L engine. (See https://4wdmechanix.com/?s=MSD+atomic for links to all the details on our 4.2L installation.) The system worked and tested well on the Rubicon Trail. Since then, MSD has received an E.O. number for Atomic EFI retrofit on 1987 and older GM V-8 engines. No Jeep 4.2L kit on the horizon. There is simply not enough demand or volume, and the Atomic EFI unit is better suited for V-8 displacement engines. The system retails for over $1500. The Mopar EFI Conversion is no longer an option. Some owners use kit components from HESCO and install donor 4.0L MPI systems on their 4.2L. Some install the entire 4.0L cylinder head with it, which requires minor modifications to coolant ports in the 4.0L head. However, you'd run into exactly the same dilemma you currently face: No California E.O. number for the donor parts. Holley (parent company for MSD now) has its own TBI units available and legal as OEM replacement for factory TBI GM V-8s and 4.3L V-6s. This is a CARB E.O. legal replacement product but not legal for your 4.2L Jeep engine. (It would not have the peripheral parts, either, like the ECM, wiring, sensors, etc.) The units for the 4.3L V-6 would likely serve well on a 4.2L Jeep. That, essentially, is what Howell has offered, a GM 4.3L TBI unit supported with GM peripheral parts and a wiring harness. You would need Howell's CARB E.O. compliant kit. Other than registering your Jeep outside Washoe or Clark County, which I would not do or recommend, it looks like Howell is your answer for a 50-State legal, California approved, Jeep 4.2L TBI conversion that would be smog legal at Washoe County....To clarify, we're at Fernley (Lyon County) and don't have inspection requirements. I still maintain emission legal vehicles. I had access to a clean burning new R2.8L Cummins diesel crate engine for our '99 XJ Cherokee but passed on the project because it would not be 50-State compliant or legal in the State of California, Washoe/Reno/Sparks or Las Vegas/Clark County. To date Cummins has not been granted a CARB E.O. number for that engine. No vehicle has been produced with the R2.8L turbodiesel engine, so there is no EPA or California certification or emissions compliance. Sound familiar? Historically, you could run an HEI distributor with a Howell system, or an O.E.M. Motorcraft system can be stripped to the bare distributor without the gaggle of emissions related parts you describe. (I ran a reliable 5-pin Chrysler module and Ford big-rotor with spacer on the AMC/Jeep Motorcraft distributors. I describe that in my Jeep Owner's Bible.) Acceptable distributor type(s) can be readily confirmed by Howell tech support if you go down that road. An HEI distributor is a simpler, one-wire solution. Make sure it's a Jeep 4.2L retrofit. If your Scrambler were not such a cult/collectible, I'd suggest installing a Chevrolet LS V8 engine with the cats and other components that must come from the donor vehicle. (For details, there's an article at the magazine on Advance Adapters' 50-State legal LS swap into their TJ Wrangler.) You could swap engines for nearly the same cost as an EFI or even a Howell TBI conversion. Our next door neighbor sold a pristine, essentially stock 1981 Scrambler a month ago for $18,000. It had been registered at Winnemucca and sold to a Texas party. When I glanced at the 4.2L, it looked "dehorned" like your engine. Very common. Howell TBI works with your stock intake manifold (BBD style) and would be the easiest and least involved path to EFI. The engines run well and delivers far better fuel efficiency, power and high altitude performance with the O2 closed-loop system. It's essentially 4.3L GM V-6 TBI with mostly off-the-shelf GM parts, available when you're stranded at Jarbidge or Austin. In wrapping this up, you do have one additional option to consider. Discuss with the DMV or smog inspectors whether you can install a complete 1991-95 Jeep Wrangler or XJ Cherokee 4.0L engine with MPI/EFI from a donor/recycled Jeep. You would need a complete engine with all peripherals, the 60-way original PCM, the engine wiring harness, all sensors, the exhaust manifold and a legal air intake system. The 4.0L block will bolt in place of your 4.2L with minor modifications to one engine bracket. There would be no impact to your frame or the overall structure and appearance of the CJ-8 Scrambler. The 4.2L spacer/shim, bellhousing and flywheel will work as well. You would need a HESCO crankshaft damper for the 4.0L short snout crankshaft/serpentine belt drive and a HESCO crankshaft position sensor that mounts at the oil pan/front of the engine. (Your 4.2L bellhousing has no provision for a crankshaft position sensor.) You need the correct crankshaft pilot bearing, simple...In the end, this would be a later 4.0L Jeep engine conversion into your 1981 CJ, which California would allow. So should Washoe County, Nevada...Without any fanfare, a 4.6L stroker build-up would not impact the appearance of the engine, and it should still pass a tailpipe emissions test. Moses
  14. Looks great, Mike! Our neighbor just sold a pristine, rust-free and original (semi-restored) CJ-8 Scrambler for $18,000. There's headroom if you want to go that far. This model has a devoted following and fetches a premium price. Above all, have fun with whatever route you take...The Jeep is at home with the plow out front and a job to do! Moses
  15. Mike...It could be hard to tell an engine swap if done correctly. The bolt in brackets could have come from new parts stock or a donor vehicle. It was, however, a major chore to swap over from an Iron Duke to a 4.2L. Emission controls, including the exhaust system, would have been involved. The 4.2L in 1981 had the BBD carburetor and a heavy complement of emissions devices, vacuum circuits, an electronic carburetor interface and ignition electronics for emissions. The engine block could have been 1980 even if original. AMC had a habit of using carryover parts until they were gone. This was not the "Big Three" level of manufacturing. Let us know how this all turns out... Moses
  16. Mike...My 1981-96 Mopar Parts Catalog shows the lower kit is correct. The upper parts look like early eighties Dodge truck, including 4x4s. The Jeep J-trucks use neither of these brake types/kits. Somebody's catalog is confusing Dodge (Mopar) trucks with the Jeep "truck" Scrambler. You should be on the right track with the lower brake parts. So the VIN on your Scrambler should have a "C" in the 8th digit. A "B" would be the 2.5L four. The four was actually a Pontiac Iron Duke in 1981-82 (first use even earlier). I had a CJ-5 with that four-cylinder engine from the factory. A great engine though a bit small for a Scrambler. It was the base engine. Starting in some '83 CJs, and from then until 1986, the CJs used a 2.46L four that was derivative of the AMC inline sixes with considerable parts interchangeability. That pushrod OHV engine became popular and lasted into the YJ and TJ Wrangler era as the (AMC-design) Jeep 2.5L four. The addition of MPI/EFI was a boon in the early nineties version of the 2.5L four, Mopar/Jeep sold many YJs with this engine. Interestingly, AMC/Jeep was smart in the CJ era. The CJ engine frame mounts bolted into place on the frame rails. The 4- and 6-cylinder engines could easily be fitted to a common frame. When I swapped a 4.2L long engine into the '81, the "conversion" was simply to find the six-cylinder frame brackets, engine brackets and motor mounts. There was a cross-support bar fitted on applications that required the added support. This design flexibility was helpful for domestic vehicles and practical for the export models that used Isuzu and Renault diesels. Unfortunately, beginning with the YJ Wrangler, AMC then Mopar abandoned the universal frame. Four-cylinder engines required one frame; six-cylinder models use a different frame. This pattern and policy prevailed through the TJ Wrangler era as well. Installing a 4.0L inline six in place of a 2.5L four in my son-in-law's 1987 YJ Wrangler required cutting off the four-cylinder frame mounts and welding modified Advance Adapters frame mounts to the frame for supporting the longer six-cylinder engine. Moses
  17. No codes, just an engine stumble as the coolant temperature reached around 140-degrees F. With the vehicle at a standstill or parked, the engine would die during this transition. Dissecting the problem ruled out the TPS, crankshaft position sensor, ignition misfire, injector flow, heated O2 sensor and the IAC valve. What was left? The MAP sensor. This 1999 XJ Cherokee engine (identical to a '91-up YJ or TJ Wrangler 4.0L MPI engine for troubleshooting purposes) had 190,000 miles on the original MAP sensor. The TPS, O2 sensor, all ignition tune-up parts and an injector cleaning with flow test had taken place within the previous 5,000 miles. So how could the MAP sensor cause the stumble during warm-up? The cold engine runs in open loop until the PCM gets the temperature sensor signal to go into closed loop. The engine started cold or hot and ran flawlessly in open loop or closed loop once the system fully transitioned into closed loop. The TPS, IAC and other devices worked well in both open loop and closed loop. Considering each sensor other than MAP, there would be no reason for the engine to stumble only on the transition to closed loop at the same precise coolant temperature each time. There would be misfires, stumbles or stalling under other operating conditions as well. The MAP sensor receives a vacuum signal that translates to an output voltage. That voltage is read by the PCM. When the MAP sensor is defective, the voltage signal can be out of normal parameters during the transition to closed loop. Here, all other devices were sending accurate voltage signals to the PCM. A quick check for a vacuum leak to the MAP sensor showed no issues. Electrical connections were not faulty, either. A MAP output voltage test while applying vacuum from a vacuum pump revealed a defective MAP sensor. A new MAP sensor cured the problem. Moses
  18. No codes, just an engine stumble as the coolant temperature reached around 140-degrees F. With the vehicle at a standstill or parked, the engine would die during this transition. Dissecting the problem ruled out the TPS, crankshaft position sensor, ignition misfire, injector flow, heated O2 sensor and the IAC valve. What was left? The MAP sensor. This 1999 XJ Cherokee engine had 190,000 miles on the original MAP sensor. The TPS, O2 sensor, all ignition tune-up parts and an injector cleaning with flow test had taken place within the previous 5,000 miles. So how could the MAP sensor cause the stumble during warm-up? The cold engine runs in open loop until the PCM gets the temperature sensor signal to go into closed loop. The engine started cold or hot and ran flawlessly in open loop or closed loop once the system fully transitioned into closed loop. The TPS, IAC and other devices worked well in both open loop and closed loop. Considering each sensor other than MAP, there would be no reason for the engine to stumble only on the transition to closed loop at the same precise coolant temperature each time. There would be misfires, stumbles or stalling under other operating conditions as well. The MAP sensor receives a vacuum signal that translates to an output voltage. That voltage is read by the PCM. When the MAP sensor is defective, the voltage signal can be out of normal parameters during the transition to closed loop. Here, all other devices were sending accurate voltage signals to the PCM. A quick check for a vacuum leak to the MAP sensor showed no issues. Electrical connections were not faulty, either. A MAP output voltage test while applying vacuum from a vacuum pump revealed a defective MAP sensor. A new MAP sensor cured the problem. Moses
  19. SomeBuckaroo...The 500 rpm is apparently within the parameter window for the IAC to control idle. Trial and error was the only approach. The FSM dodges the issue with the disclaimer about not messing with the idle stop screw. I like your plan to vacuum test the idle quality. In trying to emulate the IAC, keep in mind that the IAC valve is tapered and actuates from millisecond PCM signals. Let us know how effectively your vacuum hose test works. An approach that could refine the test would be adding an inexpensive, small ball valve at the end of your vacuum hose. This would enable better control of the air adjustments. Add an analog vacuum gauge, and you could watch for needle fluctuations. If the gauge needle wiggles, that's like a vacuum reading on an engine with leaky valves. Here, you are looking for an irregular gap between the throttle valve and a worn throttle body bore. In real time, you can see the relationship between the vacuum reading and the engine's rpm fluctuations. Moses
  20. Thanks for the feedback on my book...Glad the links and info helped!
  21. Hi, Cj7RestoClassic...Brass pipe plugs like you see in 1985CJ7's photo are available through automotive machine shops and their suppliers. They are not common "Lowe's" or "Home Depot" plumbing plugs, as you have likely discovered. Internal hex inserts are common in brass, as shown here at Amazon.com. With proper sealant, these would work if you want to use brass: https://www.amazon.com/s?k=engine+npt+plugs+brass&crid=U1TUY6MIE72U&sprefix=engine+npt+plugs+brass%2Caps%2C169&ref=nb_sb_noss Here is a link to the Dorman 090-019 steel plug with a 5/16" square insert size. It was used by Chrysler from '84-'86 as well as Ford and GM on engine castings (head or block). AMC may have used this as well...The plug is NPT 3/8" size: https://www.dormanproducts.com/p-26544-090-019.aspx Dorman follows the OEM use of steel. Looks like a zinc coating...At the link I provided above, you will find a long list of vehicles/engines that use this plug. If your size is 3/8" NPT, this would work. Moses
  22. Hi, Nash, we understand busy...Assuming that the engine is not backfiring, the float, needle and seat could be the issue. The carburetor needs a trip to your workbench with a shop manual or detailed rebuilding kit instructions. Once bench stripped with all parts accounted for, you can carefully set up the carburetor and all linkages to specification. The AFB is a straightforward rebuild if you have good instructions handy. Rebuilding results are predictable if the parts are all there and install correctly. You might want to confirm the jet and metering rod sizes to determine the original engine application. A tag and stamping numbers are a fast way to identify the carburetor. If a true Carter or Federal Mogul AFB, and not an Edelbrock, the original Carter carburetors were used on everything from late 'fifties V8s and muscle car dual four-barrel systems to sixties high performance Corvettes and big-block GM and Chrysler V8 engines. It would be smart to know the original CFM flow or engine application. You don't want to over-fuel the smaller 304 V8 engine. There were smaller V8 engine applications, and the 390 CFM AFB was popular for mildly modified Jeep V6 Dauntless 225 engines. I would confirm the application. Keep us posted on your findings... Moses
  23. Paul...I have no problem with the carburetor approach if done right. You do have the altitude challenge at Colorado. That means jetting issues with a carburetor. Some carburetor designs are less altitude sensitive. A spread-bore Quadrajet GM carburetor is actually one of my favorites. There was a 252 Buick V6 application for this carburetor, somewhat rare but suitable. Also, there were 305 Chevy V8 uses of the Quadrajet, again in step with my mantra about "find a carburetor from an engine with similar displacement". The stroker crankshaft is always an option with many gains and nothing to lose. And yes, that would make tuning with the Clifford open plenum manifold a bit easier. A 305 Chevy V8 Quadrajet, a 390 CFM AFB or an Edelbrock carburetor for a small V8 would work here. You also have the Motorcraft insights to consider or the Holley 2300 for the I-H 266 V8 that I described. Your most significant challenge is the open plenum on the Clifford manifold. No matter how many "barrels" you choose, they all feed simultaneously into that open plenum. That's not how two- and four-barrel OEM manifolds work. This is also why I stayed with the stock BBD 4.2L manifold and used an adapter to mate the Holley 2300 two-barrel (I-H variety). Jack Clifford held national drag racing records and understood how to increase inline six-cylinder power. Jack and I discussed his engineering in the eighties. The most significant feature of your manifold is its ability to flow air/fuel mixtures more uniformly to the outer cylinders of an inline six-cylinder engine ("ram" flow). That's big. Stock manifolds inherently lean or starve the outer cylinders of longer inline sixes and straight eights. Jack's aim was performance, which included a higher lift and longer duration camshaft and a header. This helped mid-range and top-end power—not the tip-in throttle smoothness needed for rock crawling. This manifold is purpose built for a specific performance gain. Keep us posted! Moses
  24. Paul...A 2150 carburetor that I really liked had plenty of CFM. If this manifold requires more CFM than the 304 V8 unit (your bore stats), there's the 5RHA2 version of the 2150 Motorcraft found on later 360 V8s in Grand Wagoneer models. Throttle bore size is 1.562". Main Venturi size is 1.21". It has an "Altitude Compensator" (Aneroid) and a throttle solenoid. I did a textbook rebuild of our '87 Grand's version of this carburetor with great results: instant starts with the choke set right, plenty of air/fuel on demand and seamless altitude compensation. This carburetor, adjusted to factory specification, is undetectable from EFI performance. However, it's calibrated for a larger displacement engine. That noted, the CFM flow might satisfy your open Clifford plenum. Is that more flow than the 4.2L/258 engine needs or can tolerate? The 1.08" 2150 flows 287 CFM. The 1.21" flows 351 CFM. I'm guessing the 1.16" is an Autolite/Motorcraft that flows around 300-310 CFM. (Do you know the engine application?) Glad you started with the 1.08", a good benchmark for your 258. I'm not concerned about the jetting on late emissions carburetors like the 360 V8. The concern is venturi size. I could never get a universal 500 CFM Holley 2300 series 2-barrel to work with a 258 (way too much carburetor). The smaller, universal 300 CFM Holley was also problematic but for other reasons. For the record, my Holley pick for the 258 Jeep engine was a stock replacement I-H 266 V8 2300-series carburetor. Off the shelf or found on an original I-H engine, this was my choice. They were used in the sixties with manual and automatic choke versions. I have the Holley tag numbers. As a rule of thumb, I look for a carburetor that fit an engine close to my engine's cubic inch displacement. That's how I isolated the I-H 266 V8 carburetor for a 258. I know that a stock 258/BBD two-barrel intake manifold with an adapter to the I-H 266 V8 Holley 2300 carburetor does work. You can try the Motorcraft 1.08" or 1.16". Either should be a prospect if originally from an AMC 304 V8. An Autolite (essentially a 2100 Motorcraft) two-barrel for a vintage Ford 292 Y-block or 260 and 289 small block V8 would be another possibility. In my experience, Clifford manifold/carburetor combinations begin with a 390 CFM carburetor or larger. Camshaft profile is another concern with your Clifford manifold's open plenum design. Essentially, this manifold works with the Clifford header and performance camshaft. Altitude compensation and jetting are always considerations. The later 360 V8 carburetors addressed that issue with the mechanical altitude compensator. Let us know how the 258 performs with the 1.08" 2150. We'll go from there. Moses
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