aussie head differences???
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From: iowa
actually 78 your right ford never did designate thier engines as small block, big block. (infact I don't believe chrysler did either for that matter) so any judge that says there is no such things as a small block 400, or other such comments needs to have his credibility questioned since his knowledge of vehicles is limited to what he has read in a hot rod magizine, and he is thus not qualified to judge a car show
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From: Sin City, USA
Originally Posted by 78bigbronco
I guess the best thing would be to find some legitimate ford documentation and stash a copy in the glove box. Or maybe a VIN # listing that shows the 302C?
Oh, and 73XAFalcon, if someone tells you ford never made a small block 400 or whatever, heres a couple things to think about. For one, small block is an industry slang that came from GM. I dont think ford ever classified its motors by small block / big block, instead they used 335 series, 385 series, etc. But using the small vs big block comparison is abvously talking about how big the block is. All the 335 series motors (clev, 351M, 400) used a thinwall, 4" bored block (atleast all that I have heard of). This is very similar to the 302 motors or the GM small-blocks. The ford 'big-blocks' had bores larger than 4" and much thicker castings. So basically the 400 has the same bore size and wall thickness as a 302/351W but it has a mucher taller deck hiegth and longer stroke. And yeah, they came in smaller and larger tranny sizes, but that has nothing to do with how big the 'block' is, just how big the tranny is. Atleast this is what I think about when someone starts arguing about big block vs small block.
Oh, and 73XAFalcon, if someone tells you ford never made a small block 400 or whatever, heres a couple things to think about. For one, small block is an industry slang that came from GM. I dont think ford ever classified its motors by small block / big block, instead they used 335 series, 385 series, etc. But using the small vs big block comparison is abvously talking about how big the block is. All the 335 series motors (clev, 351M, 400) used a thinwall, 4" bored block (atleast all that I have heard of). This is very similar to the 302 motors or the GM small-blocks. The ford 'big-blocks' had bores larger than 4" and much thicker castings. So basically the 400 has the same bore size and wall thickness as a 302/351W but it has a mucher taller deck hiegth and longer stroke. And yeah, they came in smaller and larger tranny sizes, but that has nothing to do with how big the 'block' is, just how big the tranny is. Atleast this is what I think about when someone starts arguing about big block vs small block.
As for the BB vs SB arguement, you're preaching to the choir reverend. The biggest problem for us F-L-M/B-O-P/Mopar/AMC owners is the stupid magazine writers that continue to repeat the same old myths. What is really bad now is that PHR, HR, and Car Craft all employ guys that didn't start driving until the 1990s.....heck, I've had a license since 1983 and was fetching wrenches since I was 5 and my Dad/Uncles/cousins were working on FEs, Nailheads, and the then brand new Clevelands.
--J
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From: Wisconsin
thanks for all the great info. just bought a set of 2v closed chamber aussie heads on ebay for 300. since these have the correct casting # ARD1A(E?) from australia, closed chamber with 2v ports, they seem to be the right ones i was looking for. had them magnafluxed and decked .007" to compensate for warpage. any suggestions on setting these up so they will move my 77 f250. i believe i have a stock cam but have not decided on a replacement yet...
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From: Eastern Pa
In order to really get the performance of the heads you need to have a cam that will take prper advantage of them and you need to get your deck clearance to .050 or less for quench. If you don't get both of these right you could end up with a real pinger even on higher octane gas. The cam companies give you a recommended cr for a given cam which you should go by. The split duration cams seem to be the best on these motors. To get the deck clearance you may need other pistons. I forget now where the stock ones will leave you at. Now that I think of it they may get you close. The other option is to get the block decked. This is very important! 
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From: iowa
remember it's not the piston to deck hieght that has to be .050 (tasklair your post kinda leaves that open for misinterpetation) but rather the total piston to head distance needs to be less than .050, so if your running the typical felpro gasket that is .041 nominal compressed thickness, you need to have the piston within .009 of the deck of the block. Also these blocks are never straight unless it's been decked before mine was out by .017 in one direction so get it squared up and decked to the needed hieght if you don't square it and say one side is off like mine was you could have one piston with perfect quench of .050, and the one on the opposite corner being .067 so that piston will have detonation issues big time.
first thing is find out how square that block is, and second find out the nominal compressed thickness of your head gasket, and then find out were your pistons are sitting in relationship to the block now and go from there.
first thing is find out how square that block is, and second find out the nominal compressed thickness of your head gasket, and then find out were your pistons are sitting in relationship to the block now and go from there.
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From: Eastern Pa
Quite right MOnster. Yes that is why TMI's pistons are preferred. The original Badger flat tops like I got sit down even further than a stock piston. Mine are .070 in the hole, but I am not using the aussies.
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From: PacNW
Total distance from the top of the piston to the flat surface of the head inside the bore is the key to reducing detonation. The quench effect is simply the turbulence created in the A/F mixture when the top of the piston comes in close proximity to the head during the compression stroke. It promotes a better burn and therefore less chance of detonation. Actually .050" is the maximum distance that one can expect to gain an advantage from the quench effect. .035" is the number I've seen that will give maximum quench with minimal chance of piston/head contact in a street engine with an expected RPM range of <6500. Remember heat changes things, parts expand, etc. Add a little high RPM effect and things start to make contact that shouldn't resulting in VBN (very bad noi$e$)
Now, the 400 was built with a compression height that puts the piston down the hole .060" to start with so the pistons Tim offers have an increased compression height to put them at near zero deck which allows you to tailor your C/R based on the heads you plan to use. In this case with the 302C heads you can get everything squared up, determine your desired C/R and have the pistons milled accordingly which will give you the best combination of power & driveability.
Now, the 400 was built with a compression height that puts the piston down the hole .060" to start with so the pistons Tim offers have an increased compression height to put them at near zero deck which allows you to tailor your C/R based on the heads you plan to use. In this case with the 302C heads you can get everything squared up, determine your desired C/R and have the pistons milled accordingly which will give you the best combination of power & driveability.
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From: Sin City, USA
Originally Posted by sparky69
thanks for all the great info. just bought a set of 2v closed chamber aussie heads on ebay for 300. since these have the correct casting # ARD1A(E?) from australia, closed chamber with 2v ports, they seem to be the right ones i was looking for. had them magnafluxed and decked .007" to compensate for warpage. any suggestions on setting these up so they will move my 77 f250. i believe i have a stock cam but have not decided on a replacement yet...
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From: iowa
the aussie 2v closed chamber heads are a bolt on swap for the 400 heads same port sizes, and bolt patterns same rocker arms everything with the exception of they won't have the smog port on the exhaust side, and no place to put the AIR lines.
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From: chicago burbs
yes they fit on the 400, be aware that the chamber volume is for a 302" engine and the 400 cubes will cause the compression ratio to climb. a lot. all factory and aftermarket 351M/400 intake manifolds, exhaust manifolds and headers fit the aussie heads perfectly. you would only use a Cleveland or other intake if you are building a 9.2" deck Cleveland engine, or you want a specific manifold that is not available for the M/400, like a Cleveland Parker FunnelWeb, or a 289/302 dual quad intake. crazy stuff, spacers required.
Last edited by grclark351; Sep 5, 2005 at 10:50 AM.
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