Big Six FAQ

[SuperMag]

Given the fact that the same questions come up repeatedly and we frequently have to ask the same people for the same answers (viz. "what do my casting numbers mean?"), it's been decided that a Big Six FAQ is in order.

Q: how can i tell the difference between a 240 and a 300?
A: http://fordsix.com/forum/viewtopic.php?p=365113


Q: Some guy gave me a free 300, and I want to rebuild it and put it in my Bronco. But I want to be sure I order the right parts, how do I figure out what year the motor is?
A: http://fordsix.com/forum/viewtopic.php?t=48363


Q: What's a 300 weigh?
A: About 560 lbs with manifolds & flywheel.


Q: I've heard alot about using chevy inline six rocker arms for a cheap performance gain, what is this? How hard is it to do?
A: http://fordsix.com/forum/viewtopic.php?t=48364


Q: Thinking about Roller Rockers?
A: http://fordsix.com/forum/viewtopic.php?t=48006
A: http://fordsix.com/forum/viewtopic.php?t=48364


Q: I was wondering if the Non-EFI head will work with the EFI intakes?
A: http://fordsix.com/forum/viewtopic.php?t=48366


Q: Common Cam profiles, including stock:
A: http://fordsix.com/forum/viewtopic.php?t=48357


Q: I think I have a forged steel crank in my 300. How do I tell?
A: http://fordsix.com/forum/viewtopic.php?t=46878


Q: Do I have any options for a crossflow head besides the one in development by Classinc Inlines?
A: http://fordsix.com/forum/viewtopic.php?t=48372


Q: Motor Mount Coordinates
http://fordsix.com/forum/viewtopic.php?p=365107


Q: Has anyone ever put the larger valves into a newer EFI head?? I have read somewhere that there is a clearance issue when installing the Larger Chebby valves into the EFI head?
A: http://fordsix.com/forum/viewtopic.php?t=48369


Q: Anyone know the CFM ratings of the various Motor Craft 2100 & 2150 carbs?
A: http://fordsix.com/forum/viewtopic.php?p=365109


Q: Anyone with a 53-64 F100 that is considering swapping in a Ford 240/300 inline 6 cylinder?
A: http://fordsix.com/forum/viewtopic.php?t=46462

 

[Asa]

this is all information i've gleaned from past threads, and websites of members of FSP
sources have been noted, as have originating threads
there is a possibility that the info is wrong, if so, let me know, i'll fix it

i'd like to thank BUZZNHALFDUZN for givin me a good kickstart to starting this, so far he's the only one that has PM'd me with questions, if you want something answered, ask

remember, this is a work in progress, so bear with me





Q: what are the compression ratio's for the various 300 cubers?
A:

Carb'd trucks were ~8.4:1 and EFI trucks ~8.7:1. HD engines were ~8.0:1.
-=Whittey=-

Q: how can i do that 19lb/hr injector swap?
A: read about it here (which is direct from a link on Other Evan's webpage)

Q: why would i need the 19lb/hr swap?
A: if you are making over 200 HP, then the stock injectors will not be strong enough to support your engine
the stock HP of this engine is around 140-160, so just as an upgrade on a stock engine, this is a worthless modification, once you start digging into the engine and build it up, then you'll see the benefits of it

The stock injectors are rated for 14 lbs/hr @ 39 PSI
At the 58 PSI pressure of a 300 they put out 14 * (58/39)^0.5 = 17.1#
At .50 BSFC and 80% duty cycle they'll support:

6 * 17.1 * (1/0.5) * 0.8 = 164 HP

If you push the duty cycle to 90% and the BSFC to 0.47 then

6 * 17.1 * (1/0.47) * 0.9 = 196 HP

Anywhere beyond 165 HP you may need biger injectors; by the time you get to 200 HP you will need them.

thread


Q: who makes and sells parts for our engines?
A: just about everyone sells parts for our engines, you should be able to call up just about any big name company and get parts (Summit, Performance Automotive Warehouse, etc.) just because it isn't listed, doesn't mean it isn't sold there, call them up and ask them
as for who makes parts:
Cams
Clifford Performance
Crower
Crane
Comp Cams
Lazer Cams
Accelerated Motion
ultraDyne
Blueracer
Schneider Cams
Iskanderian


Intake Manifolds
Offenhauser
Clifford Performance
Holman Moody
Edelbrock (Both it and the H-M piece are out of production and fairly rare)
Man-A-Fre (rare 3 2v intake)
Algon (Mechanical fuel injection)
Headers
Clifford Performance
MAC
Dynomax
Pace Setter
Hedman
Hooker
Doug Thorley
for mildly built engines, the EFI manifolds work wonderfully, and are much cheaper
Precision Machine ( Circle track headers) also side covers & Valvecovers
Hawes Engineering (finned side covers & fuelpump block off plates)
Roller Rocker
Crane Roller
Harland Sharp
Comp Cams

All these are off the shelf items that are currently or have previously been manufactured. I'm sure its not a complete list and it doesn't have PN's associated with them, but oh well.
-=Whittey=-

if you cannot find anything anywhere, try eBay, or Google, they are your best friends, trust me (although eBay is an evil lil demon that'll take your money if you aren't careful)

[

 

[Asa]

Q: where can i get forged pistons for my turbo/supercharged/nitroused/high CR/whatever big six? i've heard that i can drop in some 351W pistons, is there more to it than that?

A: for the 240, you can use 302 pistons, for the 300 however, you need to use either 351W, or 352FE pistons
the difference is the height of the piston from the pin to the top of the piston(aka compression height )
the 240 has a shorter stroke but a much longer rod so it requires a shorter pistont
the 300 has a longer stroke but a shorter rod so it takes a taller piston

The 351 Winsor pistons are NOT a drop in with a late model 300. You will need the rods bushed to the smaller 351W size OR purchase the earley 300 rods from Performance Automotive Warehouse for $19 each. They are the right size on the small end and have been rebuilt.
This will give you a drop in fit for pressed pins.
Bushing is the answer for floating pins.
John

source

Go to http://www.flatlanderracing.com/index.html
The TRW forged pistons are the cheapest. They are a little heavy but plenty strong. They have a .200 dome piston for the 351W that can easily be modified to work for you. They have a solid dome and the dome can be shaped to fit your requirments.
I think the Canadian http://www.hi-performance.com/ also carries them along with the Kieth Black pistons.

John

Some TRW forged piston possibilities:
PT # - COMP DIST - PIN DIA - TOP;

L2378F 1.736 912 .160 DISH 351W;
L2446F 1.769 9122 .110 DISH 351W;
L2209AF 1.800 927 .250 DOME Z-28 Chebby;
L2083NF 1.825 975 .080 DISH 352 FE;

source

 

[Asa]

Q: what is involved in changing a 240 into a 300?
A: basically, you need to swap the whole rotating assembly from the 300 into the 240
rods, pistons, crank, balancer, all need to be swapped

Essentially, the differences are:

300 rod: 6.2097"
240 rod: 6.7947"

300 Piston CH: 1.740"
240 Piston CH: 1.577"

The 65-67 rods for both motors had the .912" piston pins. And the 68-74 240's and 68-96 300's had the .975" piston pins.

 

[Asa]

Whittey came up with a system or level based performance modifications
only change that was suggested was by The Frenchtown Flyer

except that level II could use the smaller autolite two barrels, 1.01, 1.02, 1.08 or 1.21 venturii sizes

These are for Carb's.. The way I see it, Header/exhaust, weak cam, pocket porting, air intake tubes and injector swap are about all you can do to an EFI motor without needing a custom chip. At that point i'm not going to give suggestions because it really is an unknown. Anyway:


Level I - Mild Street use, Manual or Auto trans w/stock converter, stock rear gears
----------------------------------------------
Hydraulic Cam, under 205 degrees @ 0.050 lift
Dual Exhaust Manifolds from EFI motor (87-96 with the 92+ prefered)
Low Restriction Muffler(s)

Level II - Street Use, Manual or Auto trans w/stock converter, stock rear gears
----------------------------------------------
Offy SP or Cliffy intake with 350/500cfm 2bbl OR Offy DP w/390cfm
Hydraulic Cam, under 210 degrees @ 0.050 lift

Level III - Street use, Manual or Auto trans w/stock converter, 3.20 - 3.50 rear gears
----------------------------------------------
ARP fastners all around (rod, main, head)
3 angle or better valve job
Pocket ported head
9:1 Compression ratio
Upgraded Spark Box and Coil (Crane, MSD, Mallory, etc)
Offy SP or Cliffy intake with 500cfm Edelbrock or 525 Demon carb
Hydraulic Cam, 210-218 degrees @ 0.050 lift

Level IV - Street/Strip, Manual trans, Auto trans w/higher stall converter, 3.73 or higher gears
----------------------------------------------
Hypereutectic or Forged Pistons
1.94/1.60 Valves w/ 3+ angle valve job
Mild Porting
Hydraulic or Mechanical Cam 218-230 @ 0.050 lift
9.5-10:1 Compression Ratio
Header
High-Flow Cat(s) (if required)


-=Whittey=-

Addendum:

For THE optimum low, low end torque engine:

Carter YF non-electronic 1V w/ velocity stack
Holley/Edelbrock? 1V Aluminum intake manifold (rare)
Stock cam advanced 8 degrees or roller cam w/ stock specs
1.75 roller rocker arms
Well prepped head w/polished combustion chambers and bowl and valve work and extended reach plugs
Dual exhausts w/ crossover
9:1 compression w/ polished hypereutectic pistons
Early style water pump w/cast impeller
Synthetic oil

For best fuel consumption add:
Carb air modulated heat
Hotter thermostat
Premium fuel w/ increased compression
poly vee accessory drive





Q: Can somone tell me the proper procedure for adjusting the valves on a 300 with it not running?

A: Adjusting the valves on a 300 is EASY. For beginners I recommend writing down the firing order, 153624, thusly:

1 5 3
6 2 4

With a breaker bar or long handled ratchet and a 15/16 socket rotate the engine damper until the timing mark comes up to top dead center. Watch #6 cyls and #1 cyls rocker arms as you do this. On one of these two cylinders the exhaust will just be closing and the intake will start to open as you approach top dead center. If that happens on #6 then adjust #1. If it happens on #1 then adjust #6, because these two pairs are matched, as in the diagram above (5 & 2 and 3 & 4 are the other two matched pairs). So lets say you just adjusted #6. The next cylinder to adjust in the firing order is #2. Rotate the crank about a third of a rev, watching #2's buddy, #5. The exhaust rocker for #5 will be closing and the intake starting to open as you get to TDC. Adjust #2 when the two #5 rockers are in alignment, one closing and one opening.

Continue this process until you go through all six, then go through it again, to double check. With this method you can adjust all six cylinders with only two revolutions of the crank.

To speed things up you could mark your damper in three places spaced 120 deg apart. But any more I dont even look at the damper.

With practice you can run through your valves in five minutes. It will take you longer to remove the valve cover than to run the valves. Whats more you wont even have to look at the damper, just find the cylinder in the overlap cycle and start from there, adjusting the buddy cyl. Good luck. THE FRENCHTOWN FLYER

 

[benwantland]

I've decided to write some tech papers summing up answers to questions I hear all the time.

So far, I have cams and carburetors.

http://www.wantlandracing.com/tech.html

Exhaust systems sometime in the near future, I suppose.

 

[Asa]

what is the max valve lift a stock 300 can safely handle?

If I add a 240 head to a 300 with stock 300 pistons what is the max valve lift that can be handled safely?
Thanks ...

A 300 can handle valve lift in excess of .600", but the stock port flow flattens out at about .400".

Changing valve lift does not change static compression ratio but the effects of cam timing change will change the peak cylinder pressure and the speed at which the peak occurrs. If it didn't there would be little benefit to making a cam change.

thread

 

[Asa]

300 I6 dimensions

300's weigh about 490 pounds.

300 DIMENSIONS (1971 year):
FRT-FACE-OF-BLOCK to REAR-FACE-OF-BLOCK: 725 mm / 28.56"
OAL (FAN-to-CRANK-FLANGE): 931 mm / 36.65"
HEIGHT CL CRANK-to-TOP-OF-BREATHER-CAP: 486 mm / 19.12"
HT OIL-PAN-to-TOP-OF BREATHER-CAP: 690 mm / 27.17"
Sorry, no motor mount dims.

thread

Other useful 300 stats:

Deck Height: 10.000
Crank Throw: 1.990
Rod Length: 6.2097
Compression Height: 1.757
Deck Clearance: 0.0433

also:
Height of EFI intake from the top of the head: approx 8 5/16ths"
however, the IAC Valve is a good 1 1/8th" above that

these numbers might be off up to 1/4 inch
thread

 

[Asa]

Did I read correctly that the EFI intake and exhaust manifolds flow better than the older carb manifolds to the point that new headers don't make much difference?

carbed exhaust manifold

EFI front and rear exhaust manifolds (as they would appear when viewing from the passenger side)

the EFI's flow better for obvious reasons, and many consider them as good as headers for a stock to a mildly built 300, but when going for maximum power, headers are needed

thread

 

[Asa]

Q: when using a stock 300 shortblock and 240 head, what's the compression ratio that i'll get?

A:

IIRC the 240 head would bump compressioin into the 9.0-9.4 range .... there have been a few folks to do this swap ... maybe they'll chime in here.

thread

here ya go

Hi Rex,

You'll get about 9.2 to 9.5 to 1 compression with the 240 head and stock 300 pistons. Just about right with todays gas.

What does your list of modifications include? Cam, Headers?

We've got TONS of opinions!

John

and the originating thread

and according to David Vizard, that'll net you an increase in power of around 2-4% depending on prior compression ratio

thread

 

[THE FRENCHTOWN FLYER]

BBC rocker installation



--------------------------------------------------------------------------------

I have read in the forum that BBC rockers can be made to work on the big Ford 6 -early head with studs.I have searched without much luck-Does anyone know just what modifications must be made?Considering I can score a set of aluminum roller tipped rockers off a wasted BBC for nothing and have access to a machine shop,that would be no trouble.
Please,someone point me in the right direction.
Thanks
Gerald W




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THE FRENCHTOWN FLYER



Joined: 09 Nov 2002
Posts: 906
Location: FRENCHTOWN
Posted: Tue Apr 26, 2005 11:46 am Post subject:

--------------------------------------------------------------------------------

Gerald,

I personally have used the GM 250 six rockers but not the BBC. 250 has 1.75:1 ratio and BBC has 1.73:1, I believe. But the principle for installing them is the same. The roller tip must be making contact near the centerline of the valve tip; as the rocker rotates the roller is going to be moving in an arc and will want to "walk off' the tip of the valve. You must try to maximize the contact between the roller tip and the center of the valve. The most efficient use of the roller rocker arm is to have the rocker arm lever arm be at a right angle to the valve stem when the valve is at the MIDPOINT of the lift. So if you are using a cam with .500" lift then open the valve .250", bring the roller tip in contact with the end of the valve stem, and RAISE THE PIVOT POINT of the rocker arm up until a line drawn through the center of the roller tip-to-the center of the pivot point is 90 degrees to the axis of the valve stem.This method establishes the correct pushrod length if the lifter is installed and the cam lobe is on the base circle. (It helps to have a stop collar for the valve stem, a lightweight checking spring, and an adjustable length pushrod to do this procedure.)

Be sure to check for sufficient rocker arm-to-valve spring retainer clearance, rocker arm-to-stud boss/hex clearance, rocker slot-to-stud clearance, pushrod-to-head clearance, pushrod cup-to-pushrod tip clearance, oiling hole alignment, and for sufficient thread engagement of the adjusting nut. Of course do a piston-to-valve clearance check throughout the cam cycle too, and also check for rocker arm-to-valve cover clearance. Correct any clearance issues by machining.

I was at the Harland Sharp factory in Ohio last week getting some custom rocker arms built for my junk and I asked their tech guy about using other makes of engines rocker arms on our Fords. He said they don't recommend it but know it is done. I suspect the reason they don't recommend it is that they know many users will not go through the rigorous procedure I've outlined above to insure everything will work properly, but if you do it right I know your engine will run well for a long time.

Good Luck.



_________________
FORD 300 INLINE SIX - THE BEST KEPT SECRET IN DRAG RACING

 

[THE FRENCHTOWN FLYER]

No_Cure asked:


What was the smallest 2bbl ever made? What vehicle? I use an Edelbrock 600 on my current setup and am thinking of coming down to a small 2bbl until the gas thing eases up a bit. And my truck is now gonna be my daily Driver. My bronco gets around 10MPG. I know my 300 in my truck gets better than that. So I thought I might try to help that out some more by getting a smaller carb also. I used to have a little Bronco 2 with a 2.8 V6.
In the 70's versions of those they had a 280cfm 2bbl.



_________________
300 Inline BB6
4x4 cam
Offy/Edelbrock 600
EFI manifolds, Catco highflow converter,
Flowmaster Delta 50

REPLY by THE FRENCHTOWN FLYER:

When it comes to carbs for economy it's all about air/fuel ratio. Nearly all fuel systems, EFI included, run richer at WOT, usually around 11.5 - 12.5:1 A/F to try to use up every molecule of OXYGEN, even if it means introducing excess fuel to do this. This is known as LBT, or Leanest Fuel for Best Torque. At part throttle EFI systems run at 14.6:1 A/F, or thereabouts, for the best chemically correct mixture for emissions. Whereas a carb that is not constrained to run at stoich by the feedback system can run leaner than 15:1 at part throttle to try to use up every molecule of FUEL, even if it means introducing excess oxygen. This is known as MSV or Minimum fuel for Specified Vacuum. You can see that a carb running at MSV is going to use less fuel than one running at LBT, or stoich. That is why some carbed 300 engines get better fuel economy than later EFI engines, by the way.

So if you are trying to get best fuel economy the place to shoot for is running as near to WOT as you can (tall gearing) to reduce pumping losses and as lean as possible without hurting the engine. It is easier to do this with a smaller carb unless you are at WOT (LBT) all the time, which unfortunately many of us are with our heavy 300 trucks. That is why a larger carb may actually give as good or better fuel economy. It is a complex task which I have greatly over simplified but this is the general theory. Good luck.

 

[Ferris Bueller]

I have 1 of each 1994 Ford Source Books. 1 book is for trucks and vans, the other book is for cars. These are what the salesmen looked through for training and reference but these were not displayed on the showroom. There is tons of specifications data in these books but they don't say for example what size bolt you use for the tranny mount on your 94 F250. But they do list a lot of other data. For trucks I'm guessing some of the data didn't change much from 1980 to 1996. Example my 93 F150 4x2 300 5 speed longbed weighs 3980 as a base curb weight. The page I'm looking at is a truck as listed with no options. There is another page for the weight of options.

PM me for questions.

 

[THE FRENCHTOWN FLYER]

mrb1962 asked:

I took my head off this weekend and found one of my pushrods to be mushroomed where it contacts the rocker arm, looks more worn down than mushroomed really.

CAUSED BY NO LUBE AT ASSEMBLY AND INITIAL START-UP, OIL STARVATION SOMETIME DURING ITS LIFE, OR FAILURE TO CHANGE OIL REGULARLY




im doing the port/polish bit before I reassemble it.

When using EFI exhaust manifold, are you going 2 into 1 or running two pipes all the way back?

I GO TWO-INTO-ONE, BUT TWO ALL THE WAY BACK WILL WORK AS WELL IF YOU JOIN THEM WITH AN "X" OR "H" PIPE NEAR THE FRONT




Oh, one more Q.......ive heard something about the chevy rocker arms, how much of a performance gain would it be (if any) with a stock setup, including the 1bbl.........?

COMBINED WITH THE PORT / POLISH JOB YOU WILL SEE NOTICEABLE IMPROVEMENT IN PERFORMANCE WHEN USING THE CHEVY ROCKER ARMS (IT WILL HAVE THE SAME EFFECT AS USING AN AFTERMARKET RV CAM).


Thanks in advance

ALL GOOD QUESTIONS; GOOD LUCK


FTF

 

[Ferris Bueller]

WATER PUMP REPLACEMENT: On my 93 F150 300 motor I replaced the water pump and ran into these little changes. The rebuilt pump I got from Napa had thicker metal in the areas where the 4 bolts go through it and into the engine block. I had to get bolts that were 5/8" longer as in 1-1/2" long not including the head of the bolt. The other little change was the hub to mount the factory fan was just a little bigger than the one that came off of my truck. Parts store person confirmed there is 2 different sizes of hubs for fans on 300s of this era. 30mm and 33mm. But I don't know how many years previous or after 93 you can run into this, but just be ready.

 

[optikal illushun]

http://fordsix.com/forum/viewtopic.php? ... highlight= mre n teh wp dilemma

 

[THE FRENCHTOWN FLYER]

An interesting discussion on piston choices:

http://fordsix.com/forum/viewtopic.php? ... highlight=

 

[Anonymous]

As kindly provided by Frenchtown Flyer in thread

http://fordsix.com/forum/viewtopic.php?t=37978

"240 chamber is 68 cc +/- 2.
300 carb is 76 cc +/- 2.

dont have the 300 EFI handy.

A 240 head on a 300 will rasie CR from 8.4 to 8.9.
A 300 carb head on a 240 will drop CR from 8.5 to 7.9."

 

[SuperMag]

All about timing gear sets:

http://fordsix.com/forum/viewtopic.php?t=38140

 

[THE FRENCHTOWN FLYER]

Regarding head studs and rocker arms I have seen many posts by puzzled visitors. This may be because there are several kinds:

Early engines had pressed in studs of a nominal diameter of 3/8 inch and a 3/8-NF thread on the end. These studs were for rockers of the adjustable variety, using a locking nut to maintain the proper adjustment height. The rockers may have looked like the cast type or the stamped type.

Later, some heads had pressed in studs of a nominal diameter of 3/8 inch and a 5/16-NF thread on the end. These studs were for non-adjustable rockers in that the 5/16 nut was intended to be torqued down tightly against the 3/8 shoulder. All adjustment was taken up in the lifter preload.

I'm pretty sure heads of the above two types all had slotted pushrod holes to maintain rocker alignment with the end of the valve. These slotted holes need to be carefully milled out to .380 / .385 if 3/8" pushrods are to be used. Or, alternatively, they could be enlarged and pushrod guide plates installed with screw-in studs.

Finally, late model carbed engines and all EFI engines used a pedastal mounted stamped rocker arm that was held down by 5/16-NC cap screws. These also are of the non-adjustable variety. The heads have round pushrod clearance holes. Rocker alignment is maintained by stamped steel channel pieces that capture two adjacent fulcrums. Installing screw-in studs in these heads requires using pushrod guideplates.

Regarding screw-in studs: The pressed-in studs may be removed and the resultant hole used as a pilot for the 7/16-NC stud. This usually requires milling the boss down to get the screw-in stud at the correct height. Screw-in studs have either a 3/8 nominal size or a 7/16 nominal size (but they all use a 7/16 threaded hole) and the hole in the rocker fulcrums must match the size of stud you are using.

Good luck.