Just bought a 76 Camper Special for the engine and trans. Looking for stock specs. for the 460. Like to know what I'm starting out with before I rebuild. If that matters. First big block. The 351 in my 87 F-250 just wasn't doing it for me. Any advice would be great... Thanks, Dan

 

I've got a 76 F150 SuperCab with a 460 as well. I just ordered the factory shop manuals for this beast. What specs are you looking for? Maybe I can scan the pages and send them to you once I receive the books - they are due early next week.

-Vinny

 

I was looking for the specs. on the 76 460 engine. HP ? Compression ?

 

202 @ 3800 rpms. 8.0:1 CR. INTERNAL balanced motor. If it's original it will have emissions heads, which are ok heads, but, if are looking for big hp increases they will need some work.

Advice? How much hp and torque do you want? Some low cost improvements would be a better cam, a '68-'71 timing chain/gear set, and removing the emissions "hump" inside the exhaust port of the head. I've only built one post '72 460 (for someone else), so I'm sure that others have more ideas if they know what you want out of the motor. Good luck, and I'm sure you will enjoy your first BB.

 

I would like to build a torque monster for the street. Pump gas is my goal. Would around 500 horses be to much to ask? I was told it would be better to just buy a set of heads than try to do something with the 76 heads. Looking for advice, stroking it has also crossed my mind. Confused ?????????

 

Still Looking for help

 

I received the shop manuals this past weekend. Anything specific that I can pull out for you? I know you got the compression and HP from neverenough. Can't help with the mods you are asking about - I'm just a go stock kind of guy.

 

I'm working on a 460 designed for a LOT of torque too- will be glad to share some of my research so far. This is not a finished design yet - am still researching - but here is what I have so far:

Bore = 4.442 (.060 over)
Stroke - 4.300
533 cubic inch disp

Intake Valves 2.245 (stock)
Exhaust Valve 1.73 (stock) (((I think - still researching)

9.5:1 compression

750 cfm Edlebrock
2166 Edelbrock Performer Intake

Small tube headers w/mufflers

Using a Chev 409 cam spec:
Intake Duration 251 deg
Exhaust Duration 270 deg
LCA = 108
Intake Lift = .550
Exhaust Lift = .580


Dyno 2000 showing HP/Torque

2000 rpm = 254/667

2500 = 315/662

3000 = 368/644

3500 = 415/622

Am designing for my motorhome which cruises at 2600 rpm (have a gear vendor overdrive). Got a lot of weight to pull.

Would be interested in your comments/thoughts

 

ramrod25, that sounds like a great layout and it should increase your gas mileage a little too. i almost cant believe it will make so much torque so low.........sounds like an awsome engine

 

ramrod25, sounds like a nice engine on the way.. What do you think your investment in the engine will be? Where would be a good place to get the stroker kits?

EDIT
Sorry another question.... Trying to learn... What about the 4x4 extreme cam? Not sure which one to pick. With stroking, adding more cubes= HP ?? What should be the max on boring and stroking for the street? Weekend truck only I have other rides.
Thanks again, Dan

 

dk5122 - Good questions - I probably need to budget somewhere around 2 to 2.5K for the engine overhaul/modification - but that's just a a general idea right now - haven't got down to shopping for specific parts.

Do you have a timing card for the 4x4 extreme cam?? I am relying heavily on the Dyno2003 program to help me evaluate possible combinations and it can help answer your questions on which cam and bore/ stroke is ideal. I really don't know what the max on bore/stroke one can go and still build an engine that will run 100k before another overhaul. Personnally, I've been hesitant to go more than 60 over and the 4.3 stroke crank, but to be honest, I don't have any solid engineering data, or knowledge from people with hands on experience to base that decision on. I guess my thoughts are that if you go 80 over and max out the crank at 4.5 stroke - then you've left nothing for reserve - It may be a perfectly reliable combination, but would want to hear from someone who has done it and has 50K + miles on the engine. Anybody out there??

What I am doing is trying to identify what I want the engine to do.
For example: I may want the engine to develop max torque between 2000 - 3500 rpm - Then I am letting the program evaluate different cams with a given stroke/bore.

By the way - I have not ruled out putting a blower on the engine instead of stroking it. All of the information I have says you can safely go to 5psi boost with stock parts - so there is the possibility that I may spend my $ on a blower instead of a stroker crank - but it's too early to say.

I've got to better understand the effect of stroking the engine and it's effect on compression ratio. I know it will change, but I too am still looking for specific data on my engine in order to have the numbers (combustion chamber cc, deck height, distance piston is below deck at TDC, gasket thickness) etc to evaluate where the compression ratio is going to end up. I still need to use pump gas - 87-89 octane. Problem is I can't take the engine out of the mh to get all these measurments - I did send off for a book yesterday that is suppose to be the engine manual for the 1987 460 - hopefully I'll have it in a couple of weeks - maybe it will have the specs I need. In the mean time, I plan to talk to shops that build strokers and see if they can help.

I'm really impressed with the new Dyno2003 program - it has a portion of the program that allows you to define how you want the engine to run - max hp or max torque and then define the rpm band where you want to develop max torque or hp. Then you tell it what intake/carb will be used and let the program evaluate the cam profile, bore/stroke etc. I defined a set of parameters last nite and it said it had almost a million combinations to check - was still running this morning before I left for work. I'll let you know what the program comes up with.

R. Wren

 

Terrific discussion, guys!

This is striking home at an issue near to my heart, as I use a 1976 E-250 Trailer Special to pull my 24' enclosed race car trailer.

Here's a little background.

In 1976, Ford still called their 1-ton van the E-250, but if one bought a "trailer Special", one got heavy duty everything, a Dana 62 8-bolt 1-ton rear end with a 3.73:1 ratio, and their tried and true carb'd 460 engine with a C-6 3-speed automatic. My Pace Shadow trailer is rated to 10,400 lbs, and I usually tow it at about 9000 lbs. The van weighs just under 5000 lbs, so call it 14,000 total.

More than 25 years later, this combo will still tow indefinitely at 55 mph on the flat giving about 7.5 mpg. Its principal shortcoming is that it slows down to about 50 on even mild hills, even at sea level. Mountain passes are a 30-40 mph crawl in second gear. I live near San Francisco, and routingly tow to the NW (4310' pass on I-5), and as far east as Road America and Mid-Ohio (multiple 7000'-8000' passes), so better hill climbing ability is high on my list of priorities.

The engine still runs great, but I am seriously considering upgrading it in search of higher speeds on the flat and stronger hill climbing. I can save a day going each direction towing back east if I can bump my cruise speed up to 70 from 55, and the time saved is worth the extra gas to me, as I'll be working full-time for several more years (I'm 49 years old).

Over the past 13 years I've tried 3 different cams, three carbs, and 3 different intakes, with no significant improvement over the pure stock setup in the critical 2000-3500 rpm range. The cams are the stock OEM truck cam, a stock 68-71 429 cam, and a Crane "RV" cam with slightly better numbers than the OEM truck cam. I have also used the cast iron stock intake, the Edelbrock Economiser 460 and the Edelbrock Performer 460 intakes. The Economiser yielded the best fuel mileage (a solid 1.5 better than the others), but couldn't tow its way out of a wet paper bag. The Performer seems to get slightly better 3000+ rpm performance than the OEM unit, but there is nothing wrong with the OEM intake for routine towing. A "street performance" application is another issue, of course.

Same story with the cams -- no real improvement over stock. Upon reflection, I think that other restrictions in the design limit the effectiveness of the simple bolt-ons I've tried, so this time I am considering a more comprehensive appoach: long-tube headers to a true dual exhaust, a CR increase to about 8.7:1 (from the stock 8.0:1 CR), and a overdrive trans or Gearvendors unit. Perhaps even an aftermarket TBI system. Total cost about $5000 -- way cheaper than a newer used PS diesel truck or van.

I recently purchased a set of Hooker headers for the van, and am shopping for a dual exhaust system, though I may end up simply buying the pipes and bending up my own (I still have a tubing bender from my circle track racing days). There are a zillion cast, hypereutectic (sp?) and forged pistons to choose from, so finding a ~8.7:1 flat-top should be a snap. I want to keep the CR right about there to allow me to continue to run 87-octane cat pee gasoline while maximising my available torque. Nothing dampens the joy of 70 mph towing like $2/gal premium when you're getting 5 mpg...

A 9.5 CR would add some badly needed ponies and torque, but I seriously doubt one can run even premium 93-octane pump gas though our OEM iron heads without detonation at that CR while towing a heavy load. If you plan to pop for aluminum heads, though, then by all means go for it.

I have a 514 bored and stroked 460 in my 73 Mustang street rod. It was built about 10 years ago, when all such machines were custom jobs, offset grinding a stock crank to fit Chevy rods and pistons. The block is bored .080 over. Manley pop-ups make about 12:1 compression with RHS-ported aluminum SCJ heads, and a big cam assures heart-stopping performance in my 3400 lbs Stang. I have longed to insert this beast in my van, as I no longer cruise or drag race, but it doesn't really seem practical. Even if I lowered the compression to a pump-gas compatible level, I'd worry about cylinder wall thickness. Drag racing for 11 seconds is one thing. Five thousand mile tows are quite another. OTOH, I have a stock bore block sitting in the shop...

Dang it, guys ... you have me thinking again!

 

Sounds like you've done a lot of work with BB Fords. Would like to know what you think would be the max compression ratio to use for 87-89 octane pump gas?

The research I've been able to find so far indicates that the exhaust is the place to start "unstopping" this 460 monster.

I want to send you two articles for your' review.

http://www.geocities.com/MotorCity/T...92/vizard.html

This is written by David Vizard andhe has specific engineering data for design of a no/low pressure exhaust system.

Also: http://www.cafefoundation.org/research.htm

This is absolutely the best engineering study of 4 cycle exhaust events I have ever seen. They really did their study right. This emphasizes the importance of the scavanging signal to the exhaust valve during the valve overlap period.

In running my dyno program - when it gets to headers, it gives me a choice of "small tube" and "large tube" headers. Small tube is defined as "headers with primary tubes that measure 95% to 105% of the exhaust valve diameter". Large tubes are 120% to 140% of the exhaust valve diameter.

For example - on a 460, Edelbrock 2166 intake, 750 cfm carb, cam is designed by the program for low speed torque, bored 60 over with stock stroke - here is the difference in exhaust systems.


stock exhaust: (rpm hp/torque)

2000 210/558
2500 252/528
3000 289/506

Small tube header

2000 231/603
2500 272/572
3000 308/539

Large tube header

2000 231/607
2500 274/576
3000 310/543

Tuned Header ( Large pipes/minimize backpressure)

2000 236/619
2500 282/593
3000 316/553

This is just one example, but you can see that a good exhaust helps.

My dyno says a totally stock 460 puts out 228 hp/478 torque at 2500 rpm - so we can all see that this engine has a LOT of potential.

I think you've got most of what you need - just get a good exhaust system to unplug the beast.

Did you put a 429 timing set of gears on your engine?? Also, where are you running your engine timing?? I advance mine to 12 deg btdc and it really brought my 87 stock 460 to life.
Just a thought

R. Wren

 

First of all, I must apologise to dk5122 for hijacking his thread. If you'd prefer, we can start a new one.

Thanks for the terrific links, ramrod25, and for the nice words, but I am not any kind of "expert" on the 460. I've built several, from bone-stock to wet-n-wild, but still have lots to learn.

I am inclined to agree that unstopping the exhaust is the key to the 460's real potential. It doesn't matter how much you open up the intake, if the engine can't expel its spent gasses, it can't make much more power. And FWIW, I think that optimizing what one has is a surer and cheaper route to the desired level of towing power than spending big buck$ on a stroker kit or a supercharger. OTOH, if your motorhome is much heavier than my rig, you might really need the extra umph.

Your numbers for the various combos are most interesting. One thing, though, is that all the sources I have agree that a stock '76 460 maxed out at about 220 hp at 4000 rpm and 370 lbs/ft of torque at 2000 rpm (SAE net) which is a lot less torque than your program suggests. Perhaps it's because the stock exhaust is a single 2.5" pipe. I am confident that headers and dual 2.5" pipes will work wonders in the breathing department.

I just went out to the shop and measured an exhaust valve in a spare '76 head I have on the bench, as well as the primary tubes on my new headers. The intake valve measures 1.625", while the primaries are ~1.75" ID, or about 107% of the valve diameter. By your criteria that would qualify as small tube headers, and should ideally yield 500+ lbs/ft of torque. I would be delighted to get that figure!

The general concensus seems to be that unleaded gasoline will begin to detonate at max torque in 60's to 80's vintage iron heads at a compression ratio a little over one tenth of the octane. So, 87 octane gas is considered safe up to about 8.7:1 CR. If one burns 93 octane, one can expect to get up to a 9.3:1 CR before running into problems. Keep in mind that these are rough working numbers, not absolutes. Well polished heads can get away with a bit more compression, some designs are better than others, and there are variations in gasoline quality. Still, this rule of thumb should keep you safe. Now, aluminum heads can take more compression before detonation sets in as they can transfer heat to the water more quickly than can iron heads. The general rule of thumb is about half a point more compression for aluminum than with iron for a given octane of gasoline. With closed-loop EFI one can get away with a bit more compression as well, as the ECU can richen the mixture and pull timing from the engine as needed to avoid detonation. Neither of these features was available in 1976...

Interesting question about the timing chain. I did use a 68-71 429 chain in one of my engines, though it didn't seem to make any real difference at the low rpm's I use. And right now I have the timing set at the stock 8° BTDC. Thanks for the reminder -- I'll try advancing it a bit to see if that helps.

Tomorrow I'll write up the specs on my big motor. I'd like to see what your program predicts for it.

Cheers! Stan

 

Stan, don't apologize... I am sitting back right here taking the info in. This is what I want please keep it up guys. Where can I get that dyno program? What is the biggest HP gain when building the 460? I already have true 2.5" duals, no cats, 40 orig. flows, with 4" tips, can wait to get the 460 w/headers in front of it. That exhaust w/headers on my 351 really woke the truck up. Exhaust is only 4 months old so it will be fine for new engine.