Should I fix the heads I have.

junkyardjeff · September 19, 2011, 12:55:44 AM

I have a 1970 Ford 302 that was originally a 2 bbl that has a noisy guide,I think the compression ratio is 9.5 which is a little on the edge for the regular grade gas I like to use in it so I would like to find another set of heads that have just a slightly larger combustion chamber to get the compression down about a point. I did some research a year or so ago and I think the only heads that have a larger combustion chamber are heads that came out around 78 and I do like the way it runs and dont want to screw it up with a set of smog heads so what should I do,I need to figure out what I need to do since I have to pull the intake due to excessive oil consumption after installing the aluminum intake.

wayne petty · September 19, 2011, 01:14:44 AM

1996 and newer 5.0 ford explorer heads... usually have a GT visible on the left end above the exhaust port..

you will have to use longer small plugs...

if you have a 70... you might have the D0oE castings and for some reason they are very desirable..

i had a set of these on my 83 tbird.. they worked great ...

what's a shame.. i have 2 pairs of decent sbf heads just sitting.. but shipping them half way across the country is too far.. and too much..

the heads you have are conventional seats.. not hardened or induction hardened..

http://farm3.static.flickr.com/2089/2333179204_fca1dcf6c1_o.gif

http://www.castingnumbers.info/site/browse/m/Ford/p/7

edit....

going to a later head with NON adjustable pedestal rocker arms. is NOT a problem.

you can shim them up to loosen the valve adjustment.. or grind the base of the pedestal down to tighten the valve adjustment..

yes... it takes time.. but having all the valves set at the exact same lifter preload is wonderful...

junkyardjeff · September 19, 2011, 09:02:32 AM

I was hoping there were a set of later heads with about a 62 to 65 cc combustion chamber to just slightly lower the compression some,the D5 and D8 351 heads have about 10 ccs more but smaller valves and then I would have to get the spacers for the head bolts so I might have to fix what I got and try to find a thicker head gasket. I will need to have hardened seats and all new guides on my heads which will cost much more then a set of later used heads but the 10 ccs might be too much drop. I need to pull the intake since the oil consumption has gotten worse but when its off its time to fix the heads as I dont want to do it twice,I am not sure if it was the Mr gasket gaskets or a bad aluminum intake but when it goes back togather it will be getting a cast iron 4 bbl intake.

phat46 · September 19, 2011, 10:09:15 AM

A guy once told me that he ran two sets of head gaskets on a 327 to lower the compression...don't know it that would really work or not.

enjenjo · September 19, 2011, 10:33:51 AM

The 96-97 Explorer, 64.9cc, F1ZE-AA would be the head you want.

junkyardjeff · September 19, 2011, 05:34:26 PM

Over the winter I will hunt for a set of the explorer heads,I figured the heads from the 80s and up would have smaller combustion chambers due to dished pistons.

wayne petty · September 19, 2011, 07:49:43 PM

the exploder heads will have longer spark plugs like these..

http://contentinfo.autozone.com/znetcs/product-info/en/US/aut/APP764/image/4/

this is what the motorcraft version looks like\

http://contentinfo.autozone.com/znetcs/product-info/en/US/mtc/SP-432/image/4/

i don't know if any of the earlier heads used these almost 3/4 reach spark plugs...

the 96 and newer exploder was also a roller cam motor.. don't be frightened.. that it has Two 4 wire coil packs on the front of the heads..

this is normal on these..

junkyardjeff · September 19, 2011, 08:00:56 PM

I think my 89 crown vic has similar plugs.

wayne petty · September 19, 2011, 08:15:02 PM

this is what the 89 CV 5.0 plugs look like

http://contentinfo.autozone.com/znetcs/additional-prod-images/en/US/mtc/SP-482/4/image/4/

slightly different..

chimp koose · September 19, 2011, 09:20:06 PM

Phat 46 , as I understand it you can stack the old sbc steel shim head gaskets. They are .015 thick.

junkyardjeff · September 19, 2011, 11:56:57 PM

If I do put a set of the explorer heads on my 70 motor what do I use for pushrods,I presume that motor has roller lifters and they will be to short for non roller lifters. Late 70s pushrods and rocker arms?

wayne petty · September 20, 2011, 12:24:38 AM

Quote from: "junkyardjeff"If I do put a set of the explorer heads on my 70 motor what do I use for pushrods,I presume that motor has roller lifters and they will be to short for non roller lifters. Late 70s pushrods and rocker arms?

the 70 pushrods might work..

you might have to update to a non roller push rod from the 80s...

the push rod socket height on the rocker arms should be the same height..

so you should not have a problem with the 70 push rods..

again... you will want to set each cylinders pair with care.. by levering the rocker arm against the push rod.. with that cylinder set to compression stroke TDC... checking the gap... i will have to find the actual gap.. i know i posted it before.. its like more than 0.080 and less than 0.160.. with the lifter bottomed out and you holding the rocker arm with a proper lever... it might take a minute or two to bottom out the lifters..

you might want to run a pint of marvel mystery oil in your oil for a few weeks prior to the tear down and swap.. this should work the varnish out of the lifter bores so you can do so without damage..

you might also want to trickle some water through the carb with the engine running fast just prior to tear down.. to clean the carbon off the top of the pistons.. i use a soap bottle with the pop up cap.. so i can control the water flow into the motor...

why... water.. trickled in.. will turn to steam and blow the carbon off the top of the pistons if you do it right.. saves a LOT of scraping..

don't swamp the motor.. don't let it stall.. keep it revved up.. stop the water trickle if the motor slows down..

junkyardjeff · September 21, 2011, 05:33:20 PM

I found a set of the explorer heads so do I use 70 or 90s gaskets.

junkyardjeff · September 22, 2011, 11:18:58 PM

I found a set of heads with in a hundred miles but the seller is wanting 250.00,I talked to the machine shop today and its 325.00 for new guides and hardened seats so I might just have my heads repaired unless I find a set cheaper. They said thicker head gaskets should be available so unless I can get a set of explorer heads for about a hundred I will fix what I got.

wayne petty · September 23, 2011, 12:14:01 AM

as for your head gasket question...

from 88 to 95 the 5.0 used torque to yeald head bolts with flanges..
that could only be used once...

these are TTY head bolts.. with flanges.. 20 bucks a head at AZ
http://contentinfo.autozone.com/znetcs/product-info/en/US/fpr/ES72155/image/4/

any without the flanged head.. were standard..

the multilayer steel gaskets really required the use of torque to yeald head bolts...

you can use either gasket.. or one of the felpro performance head gaskets..

as for which heads to get... do the 250 buck versions include all the rocker arms?

the newer heads use retained valve seals... far superior to the dangling cup seals that the early heads used...

http://contentinfo.autozone.com/znetcs/product-info/en/US/vct/B45904/image/4/

you might want to shop around for the explorer heads...

you should be able to get a complete explorer motor for a few bucks more than that.. just swap your intake on.. swap on a special flex plate to match the early torque converter bolt pattern and the later balance..

you might need to buy a different harmonic damper.. so you can use your existing normal rotation water pump... and all the normal accessories..
but then you end up with a roller cam late model motor...

the only thing that you might want to look into.. would be a verified by the Engine id TAG.. 87 to 91 or so.. 5.0HO motor.. as those had factory forged pistons.. a slightly different firing orders than the almost identical 5.0 motors.. normal 5.0s came with one color injector tops.. the HOs came with another color.. . orange and grey are the two colors.. but i don't recall which is which right now...

the biggest problem going to a 5.0 over the 302... is the length of the distributer shaft where it sticks out below the gear... 5.0's are longer ..

engage more of the shaft.. i have been trying to find a 5.0 on the stand .. as i wanted to stick an 302 distributer in it.. and see how much vertical play the oil pump shaft really has.. i was not happy with the last one i put together for the fairlane project... but i was overruled by the owner.. so i don't know how that was resolved..

i have also been doing research.. the D0oE heads everybody wants are the 351W versions with casting number D0oE-C your 302 heads are probably DOoE-B castings.. and are probably very similar.. except for slightly smaller valves..