by Ken "Oldtime" Bushdiecker
WHAT is not a modification ?
A modification is not merely some addition to the Jeep unless the Jeep is changed in some way to to accept the addition.
Example: A set of rubber floor mats are installed in a Jeep.
WHAT is a modification ?
MODIFICATION ... A deviation from standard stock and optional stock.
Specifically any change made to the jeep that is not consistent with the service standards or any change that has not been designated as "JEEP" Approved Special Equipment and Accessories
Example: A siren is a mere addition yet drilling extra holes to mount the siren is a modification.
WHY modify ?
One should only modify to achieve desired results which are of a "rated value".
Modifications may be integrated to enhance #1 DEPENDABILITY beyond that of the standard form.
Exqample: Addition of a fuel sediment bowl.
Modifications may be integrated to enhance #2 DURABILITY beyond that of the standard form.
Exqample: Change to a stainless body
Modifications may be integrated to enhance #3 CAPABILITY beyond that of the standard form.
Exqample: Change to 11" drum brakes
Modifications may be integrated to enhance #4 VERSATILITY beyond that of the standard form.
Exqample: Addition of a winch not designated as "JEEP" Approved Special Equipment
Modifications may be integrated to enhance #5 EFFICIENCY beyond that of the standard form.
Exqample: Addition of an Overdive
Modifications may be integrated to enhance #6 SAFETY beyond that of the standard form.
Exqample: Addition of a roll bar.
Suggested decision sequencing for contemplating extensive modifications and reasons WHY.
1) Body Style and Vintage..................enhance 1,2,3,4,5,6
2) Engine............................................enhance 1,2,3,4,5
3) Frame.............................................enhance 1,2,3,4
4) Suspension....................................enhance 1,2,3,4
5) Rear Axle........................................enhance 1,2,3,4,5
6) Front Axle.......................................enhance 1,2,3,4,5
7) Brakes............................................enhance 1,2,3, 6
8) Wheels...........................................enhance 1,2,3,4,5
9) Steering..........................................enhance 1,2,3,4, 6
10) Clutch + Bellhousing.....................enhance 1,2,3
11) Transmission.................................enhance 1,2,3,4,5
12) Overdrive if desired......................enhance 1,2,3,4,5
13) Transfer Case...............................enhance 1,2,3,4,5
14) Propeller Shafts............................enhance 1,2,3,
15) Special Equipment........................enhance 1,2,3,4,5,6
16) Fuel..............................................enhance 1,2,3, 5,6
17) Cooling.........................................enhance 1,2,3,4,5
18) Exhaust........................................enhance 1,2,3
19) Instrumentation...........................enhance 1,2,3,4
20) Electrical.......................................enhance 1,2,3,4, 6
HOW to modify ?
Regardless of specific vintage and model designation the Jeep is a complete and synchronous system of integrated assemblies.
There are multiple factors to consider if and when modifing away from the service standards.
Primarily you want to end up with an operational Jeep of a rated value and the Jeep needs to remain as a complete synchronous system.
The complete synchronous system infers that all component assemblies need compliment one another.
Modifications primarily need to compliment the vintage and model designation.
Classifications are found to be most advantageous for determining how to modify.
Obvious classifications are:
STOCK ... Specifically indicates having been sourced from the factory stockpile of parts or from dealership inventory.
However the terms "stock vehicle" commonly infers the inclusion of "replacement" stock.
Stock vehicles include both standard stock and optional stock.
STOCK STANDARD...Meeting only the service standards for a particular model and vintage.
STOCK OPTIONAL... Standard plus having components designated as "JEEP" Approved Special Equipment
TRANS-VINTAGE ... Crossing of years.
TRANS-MODEL ... Crossing of models.
TRANS-MAKE ... Crossing of vehicle manufacturers.
In practice the simplest modifications involve installing "trans-vintage" parts.
This implies that all parts or assemblies are taken from Jeeps of the same model yet having a different year of manufacture.
Example: Say you have a 1953 CJ-3B and desire 12 volt power for a radio and ease of starting.
In this case the simplest solution is to install compatable 12 volt components that are standard for the 1958 and later CJ-3B.
In fact non standard components taken from the same model Jeep of the closest vintage is the ideal.
If these components do not satisfy your rated requirements then "trans-model" components should be considered.
In other words always consider the closest vintage first and a similar model Jeep as second choice.
Example: A 1959 CJ-3B owner in need of a roll bar will find that the roll bar was never standard for any vintage of his model Jeep, neither was it an option.
The closest vintage and model was the 1970 rollbar used with the CJ-5 Renegades.
Therefore one should first consisder the original "RENEGADE" roll bar in case it fits your specific needs.
Finally if nothing from the 1945 through 1985 universal series satisfies ones needs,
other makes and after market parts should be considered.
A highly modified "trans-make" Jeep is the result.
Example: Civilian Jeep with an EFI engine and sychronous compatable components to match.
1) Body Style and Vintage
If modified no particular model provides an increase of dependability, durability, capability, versatility, efficiency, or safety, over any other model.
The two notable exceptions are the increase of visabiliy and the decreased of engine area with the low hood CJ's.
As you know.... The Civilian Jeeps designated as "UNIVERSALS" have all evolved from the originals.
From the mass produced militrary light reconnisance vehicles (LRV's); the MB's and GPW's.
All civilian universal models have far exceded these LRV's in versatility.
The "Flatfender" Jeeps exclusively are the ultra short 80" wheelbased Jeeps.
In fact they are 5% smaller (frame length x body width) than the smallest of the "dog eared" Jeeps.
(M38-A1 and pre 1972 CJ-5)
In this article we have predetermined model selection as being the CJ-3B.
For well over 1/2 century the CJ-3B model remains the most advanced of these smallest offroad machines and still provide legal operation on all U.S. byways.
Obviously smaller offroad machines will "excell" in confined areas.
The CJ-3B's inherant diminutive size influences its realistic uses.
This then is its specific niche:
It has the greatest potential to traverse both on and off road better than any machine ever devised while simultaneously allowing true universal versatility.
By fully comprehending vintage evolution one can perhaps choose their ideal CJ-3B without further modifications.
Complete CJ-3B Evolution is to be covered in depth at a later time.
2) Engine Selection
When one contemplates building a modified Jeep the engine selection becomes second only to model selection.
Engine selection is near paramount because it effects virtually all other build components.
The engine choice greatly effects all of the the drivetrain component choices.
Therefore proper engine selection is critical to the complete synchronous system.
ENGINE TYPE
The engines primary function is to harness the latent force from fuel.
Engine type is fully dependant upon the chosen fuel.
Because the force for motion is derived from fuel the initial engine decision will be ones choice concerning fuel.
Few if any expect to run the Jeep engine on gasified wood fumes.
So I am only going to cover the automotive fuels that are commonly available here in the USA at the present time.
Basically then one must choose between either diesel or gasoline.
Diesel fuel contains more energy per unit than gasoline and much more than ethanol.
Fuel energy and consumption is directly related to the heat produced known as the BTU output.
One gal. of diesel yeilds 129,500 BTU's
One gal. of gasoline yeilds 114,000 BTU's.
One gal. of ethanol contains 76100 BTU's
One gal. of 10% ethanol gas has 112000 BTU's
Thereby the cost of each fuel can be directly compared to it's BTU output.
That stated one can readily understand how the the diesel and pure gasoline fuels are roughly even concerning fuel cost vs. potential energy.
Various grades of gasoline yield the same BTU's regardless of their octane ratings.
There is no advantage to be gained from using a higher octane gasoline so long as the engine operates without knocking.
The 134 Willys engines can get by on uncracked gasoline at 69 octane.
Our present post wartime gasoline is much higher concerning it's octane rating.
The higher octane rating allows for higher compression ratios and that produces a higher burn temperature.
A 134 Willys with it's low compression ratio cannot take full advantage of the much higher 87 octane that is readily available.
The trick then is to get the most energy from the commonly available 87 octane fuel.
Most all modern Otto cycle engines will perform well on 87 octane gas.
If knocking occurs one must reduce the compression ratio or raise the octane.
Otto cycle engines burning 87 octane will generally accept compression ratios as high as 9.0/1 before knocking occurs.
To get the most heat from 87 octane, look for an Otto cycle engine with a 8.5 or 9.0 / 1 compression ratio.
Higher octane and higher compressions such as a 10/1 ratio will burn the fuel at even higher temperatures.
At these super heated combustion temperatures the engines will begin to expell nitrous oxides.
Nitrous oxides are called the greenhouse gasses that are blamed for urban smog.
For this reason I will not recommend higher octanes and higher compression ratios for daily driving.
Diesel engine vs. Otto cycle engines
The main diesel engine advantage is it's inherent design dependability.
The design dependability is mainly related to it's maximum torque output that's being produced at a relatively slow rpm.
The relatively slow RPM diesel engine will proportionately decrease the internal wear.
This slower velocity increases component longevity thereby increasing the engines service life.
Compared to higher RPM Otto cycle engines, the relatively slow RPM diesel engine will drastically effect the optimum drivetrain ratios.
This RPM and ratio proportioning involves the more complex topic of Ranging.
The only diesel engine that I'll mention is....
The 192 Perkins diesel that was a rare option on a few CJ-5/CJ6's.
This particular overhead valve I-4 produces 143 ft pounds of torque at 1350 RPM.
The Otto cycle engines used for universal CJ's include the:
L-134 Go Devil........rated 060 HP @ 4000 RPM and 105 ft lbs. Torque at 2000 RPM - 6.48/1 CR
F-134 Hurricane......rated 072 HP @ 4000 RPM and 114 ft lbs. Torque at 2200 RPM - 7/1 CR
225 Dauntless.........rated 160 HP @ 4200 RPM and 235 ft lbs. Torque at 2400 RPM - 9/1 CR
232 Hi Torque.........rated 100 HP @ 3600 RPM and 185 ft lbs. Torque at 1800 RPM - 8/1 CR
258 AMC I-6 ...........rated 110 HP @ 3500 RPM and 195 ft lbs. Torque at 2000 RPM - 8/1 CR
304 AMC V-8...........rated 150 HP @ 4200 RPM and 245 ft lbs. Torque at 2500 RPM - 8.4/1 CR
*Note the above HP and Torque rating can and will vary dependant upon model and year of manufacture.
I have supplied the most common numbers used for CJ applications.
The Otto cycle engines have 1 distinct advantage over that of the diesel designs.
The Otto cycle engines are much lighter in weight.
The lower weight increases vehicle payload and helps to keep the Jeep in line with the original LRV concept.
Remember the CJ's were derived from the Light Reconnissance Vehicle.
ENGINE CONFIGURATION + FIT
From 1945 through 1975 Jeep used 4 different engine cylinder configurations in the CJ's.
The inline 4, the 90 degree V-6, the inline 6 and the 90 degree V- 8.
These different configurations provide different vibration concerns.
Of these engines the inline 6 cylinder certainly vibrates the least.
An inline 6 always has 1 cylinder under power so any fore-aft rocking motion is very limited.
Because it is not under constant combustion the inline 4 engines have an additional intermittent pause that contributes somewhat to fore-aft rocking motion..
The V-8 essentially acts like two angular opposing inline 4 cylinder engines.
The V-6 acts like two angular opposing inline 3 cylinder engines having a prolonged combustion pause from both cylinder banks.
Plus it has the additional vibrations from the odd-fire sequence.
The Oddfire V-6 is certainly the roughest running of the Jeep CJ engine configurations.
However it does include special heavy duty engine mounts which are intended to help dissipate those atypical vibrations.
The original Willys "L" head valve configuration was upgraded to the "F" head valve configuration yielding a substantial increase of power from the previous engine design.
As you well know that simple but effective change influenced the size and shape of the post 3A engine compartments.
Engine configuration, size and shape is very important. This is especially true for the pre 1972 CJ's.
If the desired Jeep model and vintage has not already been selected then the preferred engine may effect ones Jeep model or vintage selection.
The main fitment concern is the engines length and secondly it's height.
When choosing an alternative engine it is most practical to know the standard engine dimensions for the chosen Jeep.
Without body modifications, the short wheelbase CJ's are limited to inline 4 and V-6 configurations.
Basically the CJ engine must fit between the firewall and the radiator.
Secondly it must fit under the hood.
Several measurement are very helpful....
A] The engine OAL (measured from rear engine face to foreward edge of water pump)
Go Devil + Hurricane...........30"
Dauntless...........................29.875"
High Torque + Typhoon........xxx
AMC 304 V-8.......................xxx
B] The fan stickout (measured from water pump face to fans leading edge)
Go Devil + Hurricane.............1.25"
Dauntless.............................1.0"
High Torque + Typhoon..........xxx
AMC 304 V-8.........................xxx
C] The valve cover relief (measured from rear engine face to valve cover)
Go Devil + Hurricane.............1.375"
Dauntless.............................1.375"
High Torque + Typhoon..........xxx
AMC 304 V-8.........................xxx
D] The bellhousing depth (measured from front to rear)
Go Devil + Hurricane..............7.25"
Dauntless..............................6.3125"
High Torque + Typhoon...........xxx
AMC 304 V-8..........................xxx
E] The combined engine and bell OAL (measured from rear of bellhousing to foreward edge of fan)
Go Devil + Hurricane..............30"
Dauntless..............................29.875"
High Torque + Typhoon...........xxx
AMC 304 V-8..........................xxx
F] Overall engine Height (measured from bottom of oil pan to top of air cleaner)
Go Devil.................................xxx
Hurricane...............................32.25"
Dauntless (dry filter)................29.0"
Dauntless (oil bath).................xxx
High Torque + Typhoon............xxx
AMC 304 V-8...........................xxx
Some additional measurements are very helpful when figuring the complete powertrain fitment to the standard crossmember location.
G] Available drivetrain length (measured from radiator face to centerline of rear engine support.
80" wheelbase Jeeps...............42.875"
81" wheelbase Jeeps...............xxx
84" wheelbase Jeeps...............xxx
101" wheelbase Jeeps..............xxx
104" wheelbase Jeeps..............xxx
H] Combined lengths of transmission, and all adapter plates to the centerline of the crossmember support) (subtract 2.625" from the combined transmission and adapter lengths)
T90 to Go Devil + Hurricane...............................5.375"
T98 to Go Devil + Hurricane...............................11.125"
T90 to Dauntless......................................... .....8"
T15 to Dauntless......................................... .....9"
T18 mated direct to Dauntless bellhousing............10.25"
T15 to Hi Torque + Typhoon................................7.375"
T18 to Hi Torque and Typhoon.............................10.25"
T15 to AMC 304 V-8...........................................7.375"
T18 to AMC 304 V-8...........................................10.25"
ENGINE POWER + DISPLACEMENT
Obviously the required power is dependent on specific use-age and personal choice.
Here is an excellent referall concerning suggested power.
https://cj3b.info/Tech/EngineDyno.html
The 4-Wheeler's Bible, Jim Allen's invaluable reference book for off-road technique, tools and specs, gives this summary of how to evaluate how much torque you need: "How much is adequate? It's all related to engine torque versus the weight of the vehicle. If you take the rated engine torque and divide it into the curb weight, you will get the torque-to-weight ratio. Anything much over 20:1 is generally inadequate. The upper teens are acceptable, the middle teens are good, the lower teens are great, and under 10:1 is probably overkill.
Let's say the proposed Jeep weighs 2300 lbs. Then:
L-134 = 21.9 Poor
F-134 = 20 Marginal
225 = 9.8 Optimum
232 = 12.4 Great
258 = 11.8 Great
304 = 9.4 Overkill
Power is mainly increased via increased displacement.
Other power increases are certainly possible that amount to various types of engine modifications.
Those variable modifications will always have an effect upon the engine power curve.
The engine power curve is the practical range of ability.
Such modifications may also effect the engine service life.
When we change the power curve we change the operating characteristics.
It is also good to remember that increasing the engine displacement will increase the engine braking ability.
ENGINE DESIGN EFFICIENCY
The design is efficient when considering that it is the best size of engine for the task at hand.
In other words the engine displacement and it's specific design are ideal for the required task.
We have an engine that is powerful enough to do the job and not overly large nor heavy.
It is as lightweight as possible for the task at hand which always helps to increase the payload.
Weight comparison is fairly obvious.
To get a true comparison we must include all directly associated parts.
Those parts are the long block plus all engine accessories.
We need also include the engine specific components.
That is the corresponding clutch assembly, the bellhousing and the exhaust manifolds.
Weight comparisons. (Sorry, I have no precise weight figures at present)
Go -Devil
Hurricane
Dauntless
Hi Torque
Cyclone
AMC 304
To fully determine design efficiency we must compare engines to one another.
This is best accomplished via the engine power output specifications.
We use those specifications to determine the torque / displacement ratio.
Simply take the engines rated torque output and divide that by it's specific cubic inch displacement.
In this way we can directly compare any two engines to one another.
This works equally well no matter the engine type, configuration or make.
I have compared numerous types configurations and makes.
The results are quite revealing and may surprise you.
The higher the number the greater the design efficiency.
Torque / Cubic Inch Ratio
Go-Devil-----------.782
Hurricane----------.849
Dauntless--------1.043
Hi Torque----------.798
Cyclone------------.755
AMC 304-----------.806
These above chart indicates that the Dauntless is noteably more efficient concerning Torque/Displacement than the other engines listed.
And that is correct.
However as was initially mentioned that the specifications provided for the AMC engines are of the most common form used for CJ's.
Note that all post 1970 engines were detuned and retuned in order to meet EPA standards.
That will help to explain many anomalies such as 225 being superior to the later 231.
To be fair we should only compare engines having equal restrictions.
Some additional pre 1971 engine specifications:
GM 153 Stovebolt........rated 90 HP @ 4400 RPM and 152 ft lbs. Torque at 2400 RPM - 8.5/1 CR
198 Fireball............... rated 135 HP @ 4600 RPM and 205 ft lbs. Torque at 2400 RPM - 8.8/1 CR
215 Fireball................rated 155 HP @ 4600 RPM and 222 ft lbs. Torque at 2400 RPM - 8.8/1 CR
Hi Torque (2 bbl).........rated 155 HP @ 4400 RPM and 222 ft lbs. Torque at 1600 RPM - 8.5/1 CR
304 AMC V-8..............rated 210 HP @ 4400 RPM and 305 ft lbs. Torque at 2800 RPM - 9.0/1 CR
GM 350 (2 bbl)...........rated 250 HP @ 4800 RPM and 345 ft lbs. Torque at 2800 RPM - 8.5/1 CR
Additional Torque / Cubic Inch Ratio
GM Stovebolt 153 (1bbl)--------.991
Fireball 198 (1 bbl)-------------1.035
Fireball 215 (2 bbl)-------------1.021
Hi Torque 232 (2 bbl)-----------.957
AMC 304 (2 bbl)----------------1.003
GM 350 (2 bbl)------------------.986
ENGINE OPERATIONAL EFFICIENCY
{Here in this subtopic we begin to touch upon the concepts of "JEEP RANGING".}
An engine is considered as being efficient whenever it harnesses the required power from the least amount of fuel.
To do so the engine design must harness maximum force from the selected fuel.
Please refer back to the paragraph concerning various grades of gasoline.
Furthermore to achieve optimum fuel efficiency we must operate the selected engine within it's specific power band.
That is precisely what we see when we look at a dynamometer chart.
With the chart we see the engines complete operational range and also observe its practical range or it's efficient power band.
https://cj3b.info/Tech/EngineDyno.html
Basically we see 4 lines that represent the engines full operating "Range".
One pair of the lines represent "net" while the other pair of lines represent "gross".
Obviously all installed engines will be delivering "net" force.
The dynamometer itself only measures "torque" or exerted foot pounds of force.
We see how the torque line (actual force) reaches a peak value then it begins to diminish.
The HP lines are merely calculations based upon torque and RPM..
Torque is the actual force exerted while HP represents work per unit of time.
We see and easily understand that as RPM increases so increases the work.
I claim that the engine is operating at peak efficiency whenever it reaches the RPM equal to it's maximum torque output.
Maximum torque output = maximum efficient RPM.
To operate the engine any slower will not make use of the engines full potential.
To operate the engine any faster will tend to overwork the engine.
That mainly implies we are needlessly decreasing the maximum potential concerning the engines service life.
If we frequently need power far beyond the max torque output we should have chosen an engine of greater displacement.
Of course this is not true concerning race engines since we are not concerned with service life.
We can directly sense the engines maximum torque output velocity via gravitational force.
Simply use Wide Open Throttle (W.O.T.) to accelerate from various RPM's.
Maximum "G" force will be felt whenever accelerating from the engines maximum torque output.
This occurs at the maximum torque velocity because the engine components are efficiently overcoming internal resistance to crankshaft rotation.
My main point here is that the maximum developed torque drops off for a reason.
It does not drop off merely because it can.
To me this mainly indicates that the engines internal resistance relative to the opposing force of combustion has reached a point of maximum output / input ratio.
The input power is merely the force of the atomized fuel combustion.
The internal resistance mainly includes the relative efficiency of:
The carburetor including it's flow rate (bore restriction) and the proportions of the fuel mix.
The intake manifolds gaseous flow.
The camshaft lobe configuration.
The intake valve size and flow efficiency.
The spark duration and location.
The compression ratio.
The bore x stroke ratio.
The exhaust valve size and flow efficiency.
The exhaust manifold's flow.
It should now be obvious that any and all modifications from the standard engine will effect the engines specific power band.
Modifications and alterations can and will change the crankshaft velocity at maximum torque output.
3) Frame
4) Suspension
5) Rear Axle
6) Front Axle
7) Brakes
The main reason behind brake system modification is to increase SAFETY.
The DEPENDABILITY may be increased by use of a split bore master cylinder.
If upgrading to a dual safety system I recommend the system that was installed on CJ's from 1967 through 1971.
This system will readilly install onto any 1949 - 1971 CJ frame.
The main donor parts required are:
GROUP 24-06A SPLIT BORE MASTER CYLINDER
# 945556 Master cylinder 7/8"-1" (Wagner casting number FF 50314)
# 945541 Master cylinder support bracket
# 945548 Spacer plate for 945541
# 946911 Pushrod
# 946914 Cover
# 946915 Cover gasket
# 946917 Cover bolt gasket
# 946918 Cover bolt
# 946919 Master cylinder repair (Wagner # F46401)
GROUP 24-08 BRAKE PEDAL
# 942303 Pad and shank ( for use with V-6)
# 992620 Brake pedal shaft LHD
# 941046 Pedal shaft washer
# 945545 Pedal shaft support bracket
# 945546 Pedal lever (for use with F-134)
# 948181 Pedal lever ( for use with V-6)
Both DURABILITY and CAPACITY can be increased by the installation of larger brakes.
There are a few very minor drawbacks to larger brakes.
1) The smaller diameter drum potentially stays out of deep water longer.
2) The installation of larger brake reduces the leg force applied at the pedal.
This puts the driver in a more prone position concerning frontal impact.
3) In general the larger brakes weigh more.
This additional weight counteracts the original military LRV design stipulations.
Similar to a flywheel this greater weight will effect the vehicles state of inertia.
Technically it will require greater energy to get them rolling.
Therefore the Jeeps fuel EFFICIENCY will be slightly decreased.
The CJ Dana 30 disk brakes weigh the most @ xxx
Then comes the Jeep 11" Bendix drum brakes @ 21-1/2 lbs.
Followed by the Jeep 10 " Wagner drum brakes @ 18-3/4 lbs.
While the 9" Bendix system weighs in @ 13-3/4 lbs.
10" + 11" Backing plates are either RH or LH due to position of the star wheel adjuster window.
Backing plates designed for flanged type axle tubes can readily be drilled to fit earlier tapered type axle tubes.
If using a rear drum type parking brake the 11" rear plates will be required.
Otherwise any front baking plates can be used on rear axles.
10" BACKING PLATES
#945300 Left Front = Wagner #FF46421
#945301 Right Front = Wagner #FF57214
994346 Left Rear (fits flanged axle tube) = Wagner #FF72267
994347 Left Rear (fits flanged axle tube) = Wagner #FF72268
11" BACKING PLATES
8124557 Left Front = Bendix #3201047L
8124558 Right Front = Bendix #3201048R
812xxxx Left Rear = Bendix #320xxxxL (drum parking brake)
812xxxx Right Rear = Bendix #320xxxxR (drum parking brake)
Ideally the standard wheel cylinders for the particular drums should be retained.
This will aid in front /rear proportioning of the applied pressure .
No proporting valve was used on CJ before 1972 with the 11" Bendix drum brakes.
9" WHEEL CYLINDERS
#807356 = 1" Left + Right = Cast # FD 7228 (early 9" front)
#803639 = 1" Left = Casting #FD 9006 S2 (late 9" front)
#803640 = 1" Right = Casting #FD 9006 (late 9" front)
#807357 = 3/4" Rear = Casting #FD 7544 (all 9" rear)
10" WHEEL CYLINDERS
938115 = 1" Left + Right Front = Fxxxxx
991526 = 1-1/8" Left + Right Front = Casting #FD 36825
938116 = 13/16" Left Rear = Casting #F4818 = Wagner #WC370xx
938117 = 13/16" Right Rear = Casting #F4819 = Wagner #WC370xx
11" WHEEL CYLINDERS
#8124557 = 1-1/8" Left Front = Wagner #WC 18290 or WC 59240
#8124558 = 1-1/8" Right Front = Wagner #WC 18291 or WC 59241
#812xxxx = 15/16" Left Rear = Wagner #WC 59240
#812xxxx = 15/16" Right Rear = Wagner #WC 59241
The 10" Wagner system will work very well with either the stock CJ-3B or the later 67-71 CJ split bore master cylinder.
The 11" Bendix system will require the proper split bore master cylinder.
* Note the 10" Wagner uses a double lip seal drum design.
This double lip seal is a superior design used to eliminate small rocks / dirt from entering the drum.
8) Wheels
9) Steering
ROSS UPGRADES
The standard Ross box used on all flatefendered CJ's provides a 14/1 ratio and the Ross casting number for CJ-3B is T 122983
Both DURABILITY and CAPACITY can be increased by the installation of a larger Ross system.
The large Ross systems can be removed from both M38-A1 jeeps and CJ's with D-225 engines.
I believe the M38-A1 provides a 17.9 /1 ratio and the Ross casting number is TL 122995.
The Ross sytem for D-225 CJ's provides a 19/1 ratio and the casting number is TL 122987
If changing over to one of the HD Ross systems the drag link may benefit from adjustment. See: http://z4.invisionfree.com/CJ3B_Bulletin_B...?showtopic=3857
SAGINAW UPGRADES
10) Clutch + Bellhousing
Clutch Control
There were many variations of lever / tube assembly that were manufactured for use with various clutch makes, various clutch sizes and various transmissions.
From the factory none of the lever/ tube assemblies were ever equipped with lubrication fittings.
The pivot stud bracket must be removed from the frame in order to take the assembly apart and lubricate pivot studs inside the tube.
Yes the lever / tube assembly is often and easily modified to accept a grease zerk.
Simply drill and tap for the zerk near the middle bottom of the control tube.
The standard seals and pads that are used inside the tube can remain intact.
I suggest that the standard pad disk should be replaced with a common washer.
11) Transmission
12) Overdrive if desired
13) Transfer Case
14) Propeller Shafts
15) Special Equipment
16) Fuel
17) Cooling
For a CJ-3B with Dauntless 225 engine I suggest the use of a Dauntless V-6 radiator.
The Dauntless V-6 radiator provides 3 advantages.
1] The water inlet is centered on the upper tank to align with the engine outlet.
2] The water outlet is on the lower right tank to align with the water pump inlet.
3] The Dauntless V-6 radiator shroud # 941547 will fit all Dauntless V-6 radiators.
The Dauntless V-6 radiator has 1 dissadvantage when installed on a CJ-3B.
1] Cutom angle brackets must be fabricated to fit this radiator to the CJ-3B grill gaurd bolt pattern.
Jeep used 3 different versions of these Modine radiators on CJ-5, 6 and Jeepsters from 1965 though 1971.
17" wide core # 941073
22" wide core # 943290 (after 1967)
22" wide HD core # 943292 (after 1967)
Otherwise I suggest that one modify the stock CJ-3B Harrison radiator.
The coolant inlet should be centered on the upper tank and the outlet should be positioned to the right on the lower tank.
The CJ-3B Harrison radiator may require a custom built shroud to increase it's cooling efficiency.
Remember the efficiency of the existing copper core is superior to that of aluminum.
The Modine radiator used on the standard F-134 equipped CJ-5, 6 is also a viable option.
This particular radiator is a direct bolt fit onto the CJ-3B grille gaurd.
No drilling nor additional brackets are required.
The main difference between the F-134 Modine and the F-134 Harrison is that the Modine inlet is centered where the Harrison inlet is left of center.
The F-134 Modine radiator will only need to have the outlet pipe moved to the right side of the lower tank.
Here again a custom shroud may be required to increase it's cooling efficiency.
18) Exhaust
19) Instrumentation
20) Electrical
Thanks to Ken "Oldtime" Bushdiecker. -- Derek Redmond
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