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Discussion Starter #1
allright - folks...

I need some expert advice....

I have a 78 F150 Lariat with a D1VE 460 hiding under hood. It is a bit tired and needs a suitable transplant. I came across a 1971 Linc Conti with a D1VE 460 and C6 running fine, low miles and complete for 400.00 smackaroos.

From the research I have done, I have found that this year vehicle has 365 HP from the factory. It also is slated to have a 10.5 Compression ratio.

My question....Can I swap the 78 460 heads onto the older 71 engine to lower the compression? Or will it stay the same? Also, does anyone know the compression / HP figures for the 73-78 Ford 460's?

With gas prices high and this being a 460 daily driver...I would love to lower the compression and run a lower octane gas.

Thanks in advance for all the great answers to come...
 
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Your heads will swap on and lower the compression. Probably to the exact amt you have now. Most 460's only had large or small chambers. The D1VE heads are worth a few buck on if they are closed chamber with screwin studs.
 
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That is what I was thinkin'...

I plan to keep the original 460 and eventually rebuild to stock and replant it back in the truck when I restore it to original.

The heads and intake off of the Linc 460 will be sold then later - as a complete unit.

Thanks for the info...

Fastlane Ford
 

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IIRC the later (73 and later) 460 also had a deeper dish in the piston. Early 460s had a shallow dish and the 429 CobraJet had flat top pistons with relief cuts for the valves.
 
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Discussion Starter #5
anyone know any HP figures....compression figures for the 73-78 460's??

Thanks for the info guys!
 
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'73 & later engines are real wheel rated & very low. Swapping the heads will lower the CR but drastically reduce performance as well. Instead of getting rid of the D0VE heads I personally would open the combustion chambers on them to lower the CR & help un-shroud the valve to promote better flow. This will give you a streetable CR with a ton of power. Done it a few times. BTW I'm SOOOOOO jealous of you getting such a deal! I put this combo in a '71 Grande & ran 13.20's all day long on pump gas.
70 Cyclone Spoiler 429 SCJ 4:30 Drag-pak
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65 Mustang one-owner
66 Mustang 8-second street legal drag car
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76 20' E-350 motor home
Too many parts cars to mention
 
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Did Ford change the intake - exhaust runners of the heads for 72 and up models?

Here is some info I dug up...

For 1971 - 365HP gross - 235 net

"for 1972...Compression was lowered from 10.5:1 to 8.5:1, allowing the car to be run on regular gas instead of premium. This reduced both emissions and horsepower; the rating was now down a full 10% to 212 net...from 235HP."

"For 1973 - Mechanical changes were further necessitated by emissions regulations. New this year was the EGR valve (exhaust gas recirculation). This device rerouted some of the exhaust gases back into the combustion chamber to cool it off, resulting in lower levels of nitrous oxide. Compression was reduced to 8.0:1 though due to other minor modifications horsepower was actually up to 219."

With all this in mind...if the heads runners and combustion chambers are identical from 72-78...how was the compression change made? By pistons? or by a different thickness gasket on the head?

This is getting interesting....the D1VE block I am getting....I am not sure of the heads yet, although it does have the D0VE 4bbl intake....and it is supposedly the 365 HP 10.5 compression engine.

Any and all thoughts welcome...

Fastlane Ford
 
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Discussion Starter #9
I am no expert but I have been working with a 460 for the past couple of months and have found quite a bit of info on the network54 forum on this topic. One of the members has a good website for anything head related (http://reincarnation-automotive.com/). In '72 the compression ratio dropped to 8.5:1 but that was due to larger combustion chambers and piston dish not sure how much to attribute to each but you can do some quick math. If memory serves me the D0VE and D1VE castings had ~72cc chambers and the D3VE had between 92 and 95cc chambers. If you don't have D3VE heads then I don't know what to tell you but on a '78 that should be what is on there. The deck height was raised slightly around '73 also helping to reduce compression. I would have to guess you will be below 10:1 if you are using a block and pistons from a pre'72 and D3VE heads.
As far as HP figures, I found a historical website on lincolns and supposedly the Hp figure only dropped 10% with the 2pt reduction in compression and then some was gained back with the advances of some of the later D3VE head work.
Hope this helps.
Micah
 

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Cobrapatrol is correct. the piston on the 78 engine have a deeper dish. so the compression will not be quite as low if you put the 78 heads on the early engine. the intakes are the same. By the real question here is why? The 71 engine will run fine on pump gas even with the compression.
 

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The timing is different on the '73 and later motors. They were retarded with the timing gears, for EPA. This hurt the performance a lot, also. I would use the whole motor from the Lincoln.
Also, the heads have passages in the front and rear with smog tubes attached. This is the clean burn set-up you were talking about. Get rid of the tubes, and plud up the holes. Any machine shop can supply stuff to fix this problem. The tubes always leak, and good way to burn valves....
 
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Remember - I mentioned earlier -

"With gas prices high and this being a 460 daily driver...I would love to lower the compression and run a lower octane gas"

This is a 5000 lb truck and to run the 10.5 compression engine I would be running super unleaded, which where I live is 1.65 right now.

I was getting 12-15 mpg with the stock 78 460....15-16 on highway continuous.

Fastlane Ford
 
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The fella at Pony Carbs told me that also. He mentioned doing some research if I was going to rebuild my original engine. He said to use the early timing gear and settings due to the retarding of the timing. Right on...

Is there any detrimental affects from plugging the tube holes up? I mean - don't the holes run the length of the head from front to rear and tap into each cylinders exhaust port? Would there be any type of back pressure problems?

Also - the engine has a smog set up...and it's 4 bbl intake has an EGR set up on it. My 460 is stripped of all these components. I planned to use my intake and front dress pieces for proper fitment and alignment, thus eliminating the smog components. This should still prove as a 75-100 hp improvement over my stock 460 now...

should be fun!!

Thanks for the advice everyone.

Fastlane Ford
 
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Discussion Starter #14
Blocks have different deck heights, minor piston changes & a combustion chamber change. Personally any head I can't reach through & easily touch the exhaust valve I pitch in the parts bush.
 
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""Personally any head I can't reach through & easily touch the exhaust valve I pitch in the parts bush. ""

why do you say this? and what is the logic? just wondering...

Also do you have the figures for the deck heights any hard and fast Ford numbers would be very helpful.

Thanks for the info!

Fastlane Ford
 
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Discussion Starter #16
Don't have my books close to know the deck heights, all I use is '68/71 blocks. The heads of the no finger in the exhaust type are so restrictive I find them useless & they like to crack. I have way too many early ones to use the late ones.
 
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