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Anyone put C8VE-A heads on a 1977 460. what cam would work best.I guess the deck height is a little higher,is that a problem .I'll probably change the studs and use roller rockers .Any info would be appreciated
 

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I've dome the '68 "Thunder Jet" heads on '73 460....which is the same as your '77 engine. makes for a nice jump in compression ratio.
Like al 429-460 production heads, they really need the Themactor bump ground out of the exhaust port, it really clogs the port up...luckily, it is easy to get to a grind out.

We also used BBC style rocker arm studs and full roller rockers to replace the factory cast rail rockers the '68 uses stock....you have to mill the stud bosses down 1/8", because for anything other than the rail tip rockers you need a pushrod guideplate to hold the rocker in alignment on the valve tip. You'll also need hardened pushrods, to go with the use of guideplates….stock pushrods will get ate up running against a guuideplate.

You'll also want to replace the stock timing chain set, as it is an emissions design that has the cam 8° retarded. We used a Milodon 9-keyway, but any performance 3-keyway roller chain set should work.

Deck height difference on the block won't hurt anything...you can't do anything about it anyway unless you have the block torn down to bare, so it can be decked....I don't know if any thin gasket solution for the 460 to avoid this deck cut issue. It's less than ideal on quench clearance in a taller block, but it didn't seem to bother with what we were doing with it

Can't help you pick a cam without knowing what you want to do with the engine...a drag car needs a far different cam from a trailer towing pick-up or a cruising Lincoln.

The engine we did went into a big '77 Thunderbird with a C6 trans, 2800 stall and 3.25 rear geared 9" and had to make enough vacuum to run the headlight doors and all the heater/Air Conditioner controls, we used a Crower Beast cam. Great power from 2000 rpm up to 5500 rpm, it was a Corvette killer on the open toll road in the mid 1990's, thing had no trouble running 140 MPH, it had the entire front and rear suspension out from under a '76 LTD cop car
 

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Anyone put C8VE-A heads on a 1977 460. what cam would work best.I guess the deck height is a little higher,is that a problem .I'll probably change the studs and use roller rockers .Any info would be appreciated
The C8VE-A (1968) heads are about 75cc's and were designed with no hard seats to run on leaded gasoline, so you can either spend the money to have a machine shop to cut the heads and install hard seats or you can take your chances with valve recession (valves eating their way down into the heads). This may not be a huge problem, depending on the miles that you intend to put on the motor, but if this was to be a daily driver, I'd install hard seats.

1977 heads were about 95cc combustion chambers, so the static compression ratio with 75cc heads will be well over 10:1, making it problematic for running the motor on pump gas without detonating. Most everyone will agree that the builder should limit SCR to 9.5:1 or less when using iron heads. Realistically, using iron heads, this parts interchange would require a piston change (dished crown) to bring SCR down enough to prevent detonation.

An alternate plan might be to use Edelbrock aluminum heads, which will allow the use of pump gas up to about 10.5:1 without detonating, due to the ability of aluminum to shed heat much more quickly than cast iron. It would also negate the high cost of cutting the iron heads for hard seats. With this plan, I would zero deck the block and use a 0.035" to 0.045" compressed thickness composition head gasket to prevent fretting of the aluminum.

Do not choose a cam until you have the SCR nailed down.

Let me help you out a little on the block deck height question. When you increase the block deck height, you also increase the piston deck height (distance from the crown of the piston to the top of the block where the heads bolt on). When you do this, you destroy the squish/quench dimension that helps the motor to tolerate pump gas without detonating. Ideal squish/quench is measured at 0.035" to 0.045", so when you increase squish/quench by extending the block deck height (without extending the piston compression distance at the same time, you make the motor less tolerant for running on pump gas without detonating. An aluminum head does not tolerate a steel shim gasket very well, and you'll find that all aluminum head producers will recommend a composition gasket, 0.035" to 0.045".

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Discussion Starter #4
Thanks again guys for the info. The motor is in a 1949 merc M47 pickup, we built it about 3 years ago.It has a TCI weld in front end -mustang11 style,C6 tranny,TCI 4 link with coilovers 9" rearend ,tubbed and big tires.I changed the cam timing and put a performer intake and 650 edelbrock carb, MSD stand alone distributor.It's just a toy. -but it needs more power,drive it on the street ,maybe a little drag racing . did U use chev guide plates and were the roller rockers 1.73.Do they still make that cam?I'll just run a little av gas and some lead additive.What carb did U use? I'ii be running 2.8:1 gears.
 

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Best cam to use with a 2.80:1 rear gear will be very close to stock, but the high SCR won't like it much. The motor will build high cylinder pressure and be detonation-prone. You've painted yourself into a corner.
 

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Won't the compression be a little less with the increased deck height? I have a 1970 lincoln MK111 I run about 20% av gas in. It has 10.5:1 compression and tall gears weighs about 5000 lbs and it goes real good. .The pickup is less than 4000Lbs.I think you're right about building it with edelbock ,but I already have these parts.
 

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Yeah ,the MK111 detonates on 91 ,but give it some av gas it purrs like a kitten
If you reduce the deck height, you will increase the volume of the combustion chamber quench area. That will lead to higher combustion chamber temperatures and preignition. The automotive engineers did not call it “quench” for nothing.
 

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If you reduce the deck height, you will increase the volume of the combustion chamber quench area. That will lead to higher combustion chamber temperatures and preignition. The automotive engineers did not call it “quench” for nothing.
Negatory there cowboy, if you reduce the block deck height and leave everything else alone, you will decrease the volume of the combustion chamber quench area. Doing this will decrease the probability of detonation/pre-ignition. However, if you cut the block deck height without engineering the proper head gasket thickness, you run the risk of a piston/head collision.
 

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Thanks again guys for the info. The motor is in a 1949 merc M47 pickup, we built it about 3 years ago.It has a TCI weld in front end -mustang11 style,C6 tranny,TCI 4 link with coilovers 9" rearend ,tubbed and big tires.I changed the cam timing and put a performer intake and 650 edelbrock carb, MSD stand alone distributor.It's just a toy. -but it needs more power,drive it on the street ,maybe a little drag racing . did U use chev guide plates and were the roller rockers 1.73.Do they still make that cam?I'll just run a little av gas and some lead additive.What carb did U use? I'ii be running 2.8:1 gears.
Crower still makes the Beast series, but I'm sure there is probably something better out there today. Rockers were Harland Sharp's, guideplates were Ford MotorSport. Intake was Edelbrock Performer with a 1" open spacer...they didn't make a Performer RPM back then, and the Torker isn't worth the aluminum it's cast out of.

We used both a reworked and polished Holley 780cfm Vacuum Secondary and a 800cfm Double Pumper, no real difference between the two but the Vacuum carb was better on cruising fuel mileage.
 

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I run a similar combo. The '77 short block should have the 22cc bath tub pistons. Assuming a stock bore and the piston .025 down in the hole your compression ratio will be around 9.2-1.

With that rear gear I would use a Lunati 80460 cam. This should work with the stock valvetrain but you will need to check clearances.

The Lunati 61601 is another good choice but I prefer the additional exhaust duration of the 80460 with stock iron heads.
 
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