[72FordGTS]

I am planning on building my 1972 400 for my '72 Torino. I have been looking at Tim Meyer's parts. He offers a piston for stock heads that produces about 9.4:1 compression with a .030 overbore. He also offeres a piston that makes 9.43:1 with Aussie heads and a .030 overbore.

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I know the Aussie heads are closed chamber while my stock 400 heads are open chamber. I was initially looking at getting some Aussie heads but Meyer has none in stock. If the compression is pretty much the same between stock and Aussie heads, is there any real advantage to running the closed chamber heads? Is it really worthe the extra coin?

I am only planning on building a street only engine with lots of torque and moderate horsepower levels.

Any advice appreciated.

 

[scrnic1]

I used the edelbrock heads on my 400. From what I remember, the closed chamber heads resist(so to speak) detonation better than an open chamber head. My 400 is in a 75 ranchero and very streetable. With stock replacement Keith black pistons, and the edelbrock heads, I ended up with about 9.75:1 compression. I really like these heads personally, and can confidently recomend them.

 

[72FordGTS]

Thanks for the information. So you're saying that the closed chamber heads would be more resistant to detonation? I always heard the detonation problems with the 400 were related much to the fact that the pistons were below deck height. I know T Meyer pistons are supposed to give zero deck height.

I am not interested in Edelbrock heads, a little too pricey for me, plus I want my car to "appear" stock under the hood, which it won't with those heads.

Does anyone know if the 1972 400 Ford had heads with smaller combustion chambers than the 1973+? The 1971 400 had a 9:1 compression, and the 1972 was 8.4:1, and 1973+ was 8:1. The only change between 1971-2 was the dished pistons. It makes more sense that they increased the combustion chamber size in 1973 than dished the pistons further?

 

[scrnic1]

The chambers shape and size have a similar effect on detonation as compared to the installed height of the piston i BELIEVE, but dont quote me on that... IDK if the chambers grew, but the dish got bigger and bigger...year after year, i do know that. You might be able to find a set of NOS 71' 400 pistons from a parts house, or summit, or Jegs. I read a post recently where a guy found a set of 71' 400 NOS pistons from summit...pissed me off cause I didnt even think to ask about them when i built my 400... Tmeyer has really nice stuff, if you can afford his pistons, by all means go that route, its less than heads for sure. Probe also has nice pistons, and they will cut out the wrist pin hole on a set of cleveland pistons to accomidate a 400 wrist pin. IDK about the aussie heads... the way i looked at it was simple...Locate a set of heads, have them inspected, cleaned, rebuilt, new valves, seats, guides, port work, milling them flat...by the time you get them done, you still have an OLD design that wasnt that good to begin with. Just my .02 FM magazine did a nice article on cleveland port design, which i read, which is where i get the basis for my .02

Edit: Note on the edelbrock heads-They come assembled with ARP screw in studs, guide plates, and good valve springs which work up to .600 valve lift, and stainless valves...You could fill in the logo with epoxy and paint them to match the engine, very few people would notice them untill they saw your tail lights ;-)

Thanks for the information. So you're saying that the closed chamber heads would be more resistant to detonation? I always heard the detonation problems with the 400 were related much to the fact that the pistons were below deck height. I know T Meyer pistons are supposed to give zero deck height.

I am not interested in Edelbrock heads, a little too pricey for me, plus I want my car to "appear" stock under the hood, which it won't with those heads.

Does anyone know if the 1972 400 Ford had heads with smaller combustion chambers than the 1973+? The 1971 400 had a 9:1 compression, and the 1972 was 8.4:1, and 1973+ was 8:1. The only change between 1971-2 was the dished pistons. It makes more sense that they increased the combustion chamber size in 1973 than dished the pistons further?

 

[torkair]

The drops in compression in the 400 are due to the horrible dished pistons, the heads had very minimal changes and are near identical to Cleveland 2v heads, although beginning in '75 Ford began casting the heads with a water jacket in the roof of the exhaust ports and therefore should be avoided!

The Edlebrock Cleveland heads are a good buy and are readily available, but for the same money you could get a set of AFR or CHI heads which are a better overall performance head.

Alternatively you might be able to score a really nice set of closed chamber 4v heads as well as some intake spacer plates so that you can use any of the 4v intake options for a Cleveland.

Lastly, instead of cutting larger wrist pin holes or getting custom pistons you could have your machine shop bush the small ends of your connecting rods in order to accept a standard Cleveland wrist pin and therefore use off the shelf Cleveland pistons.

 

[scrnic1]

The only thing torkair said that i disagree with is using a 4v head on a street engine. While they arent as bad as people seem to think at low speeds, the problem arrises when you need headers and an intake. They have different ports, they are more rare, therefore the bolt on parts are that much more...and just to beat a dead horse...you really cant take advantage of the big ports at normal Rpm's

 

[DanH]

The only thing torkair said that i disagree with is using a 4v head on a street engine. While they arent as bad as people seem to think at low speeds, the problem arrises when you need headers and an intake. They have different ports, they are more rare, therefore the bolt on parts are that much more...and just to beat a dead horse...you really cant take advantage of the big ports at normal Rpm's

Exactly whats is normal rpm ?

I know normal rpm for most production cars is idle to 3000 rpm , that 3k is about 80 mph to 100 mph

Normal !!! OK . seems to be a lot that don't want normal

 

[scrnic1]

Exactly whats is normal rpm ?

I know normal rpm for most production cars is idle to 3000 rpm , that 3k is about 80 mph to 100 mph

Normal !!! OK . seems to be a lot that don't want normal

I'm thinking normal in terms of a daily driven street vehicle, that doesnt need to be wound up over 4k all the time to take advantage of the performance parts installed. Please don't argue the semantics of normal, I get it, normal is different for everyone..forgive me o mighty DanH...

 

[72FordGTS]

I guess I should have mentioned I plan to completely rebuild my engine during as well. So I will need new pistons regardless, and of course I am not going to reinstall the stock dished pistons. I was probably going to get my rebuild parts through T Meyer, especially since he has decent pistons for the 400. I am not really interested in the NOS 1971 400 pistons, as they would only bring me up to 9:1 compresson. At least with TMeyer I can get 9.4:1. His pistons aren't overly expensive, about $240 when purchased with a rebuild kit.

That said, I am probably just going to stick with my stock 400 heads and with the new pistons and a decent cam. I am hoping this won't cause detonation problems, but I guess I won't know untill I am done. It sounds like the Aussie heads aren't worth the cost. I am still not sure if they offer any real advantage when I can get almost the exact same compression ration with the stock open chambered heads.

 

[torkair]

The Aussie heads will bring your compression up quite a bit if using flat top pistons, however in order to get the same CR with the open chamber heads you will either need to mill a significant amount off of them or use domed pistons. You're gonna end up spending the same amount getting a set of heads rebuilt regardless of which ones you go with wo the choice is totally yours, personally I'd go with the Aussie heads though.

 

[72FordGTS]

The Aussie heads will bring your compression up quite a bit if using flat top pistons, however in order to get the same CR with the open chamber heads you will either need to mill a significant amount off of them or use domed pistons. You're gonna end up spending the same amount getting a set of heads rebuilt regardless of which ones you go with wo the choice is totally yours, personally I'd go with the Aussie heads though.

Take a look at the link I posted in my first post. TMeyer sells pistons that will offer 9.4:1 with stock heads, no milling, and a zero deck height. He sells pistons for the Aussie heads and a 400 and it's only 9.43:1, slightly higher. For the street 9.4:1 should be fine, I was aiming somewhere around 9.5:1 compression (even if I used Aussie heads).

Yes, you're right about the cost of getting the heads redone, but it will save me more than a few dollars not having to buy Aussie cores. And that said, it's a moot point, because even if I wanted them, T Meyer has none in stock.

 

[scrnic1]

Although I dont have another source, Tmeyer can't be the only source for Aussie heads... What's your budget? There's lots of good ideas to share, but, if you've already made up your mind, why ask the public at large?

 

[scrnic1]

I guess I should have mentioned I plan to completely rebuild my engine during as well. So I will need new pistons regardless, and of course I am not going to reinstall the stock dished pistons. I was probably going to get my rebuild parts through T Meyer, especially since he has decent pistons for the 400. I am not really interested in the NOS 1971 400 pistons, as they would only bring me up to 9:1 compresson. At least with TMeyer I can get 9.4:1. His pistons aren't overly expensive, about $240 when purchased with a rebuild kit.

That said, I am probably just going to stick with my stock 400 heads and with the new pistons and a decent cam. I am hoping this won't cause detonation problems, but I guess I won't know untill I am done. It sounds like the Aussie heads aren't worth the cost. I am still not sure if they offer any real advantage when I can get almost the exact same compression ration with the stock open chambered heads.

Why suffer the expense of rebuilding a 400 ford, and still be stuck with non adjustable rockets, **** combustion chamber design, poor heat transfer, and a tendency to detonate under load with even slightly advanced timing(even with stock CR)? I've always used stock heads myself, until I built my 400. My plan was very similar to yours. I would have very seriously regretted not upgrading the heads knowing what I know now.

 

[72FordGTS]

Why suffer the expense of rebuilding a 400 ford, and still be stuck with non adjustable rockets, **** combustion chamber design, poor heat transfer, and a tendency to detonate under load with even slightly advanced timing(even with stock CR)? I've always used stock heads myself, until I built my 400. My plan was very similar to yours. I would have very seriously regretted not upgrading the heads knowing what I know now.

I shouldn't have sounded so decisive in my last post, because I am really not. My original point of the post was to see if there is any real advantage to the closed chamber head vs open chamber if compression is equal. If there are other souces for Aussie heads, I haven't found them yet, but please share. I haven't ruled them out entirely. I just don't see what the advantage is if the compression is equal, that was the point I was trying to make.

I hear your argument about the e-brocks and you make a lot of sense. Don't foget though that I am in Canada, and parts are PRICEY up here. Either we pay the highly marked up prices of our local vendors, or we pay the crazy shipping costs from the US. It's a lose lose. I was figuring a budget of $5000, including machine work, and the build. So I am not sure if Aluminum heads would fall in that.

Furthermore, my ultmate goal is to make the 400 a decent performer, not the weak smog engine it was from the factory. I also plan on making the car appear as stock as possible from the outside of the engine.

I really do appreciate all the advice and discussion so far. I am just trying to learn.

 

[oldgator]

Seems everyone whats to give you advice, but no one wants to answer your question..

9.4:1 and your stock heads with a moderate/decent cam will not
give you any detonation...

rebuild and enjoy to money you've saved..

Good Luck

 

[scrnic1]

It will detonate plenty if he tries to advance his timing much with those stocker heads...that said...Hes right on the other accounts. If aluminum heads are out of your budget, get a set of adapter plates so that you can run a Cleveland intake, a nice healthy hydraulic flat tappet cam, headers and plenty of carb. You will enjoy it! I had no idea Canada enjoyed so much higher prices on parts. Maybe you can find someone you trust to buy them in the states and ship them to you. Whatever heads you do, get them prepped with screw in 7/16" studs and guide plates...if you do, Save some money on the roller rockers and use rollers for a Big block Chevy, and just bump up your cam lift a little when your picking it out to compensate for the slightly shorter ratio on the Chevy rockers.

 

[DanH]

It will detonate plenty if he tries to advance his timing much with those stocker heads...that said...Hes right on the other accounts. If aluminum heads are out of your budget, get a set of adapter plates so that you can run a Cleveland intake, a nice healthy hydraulic flat tappet cam, headers and plenty of carb. You will enjoy it! I had no idea Canada enjoyed so much higher prices on parts. Maybe you can find someone you trust to buy them in the states and ship them to you. Whatever heads you do, get them prepped with screw in 7/16" studs and guide plates...if you do, Save some money on the roller rockers and use rollers for a Big block Chevy, and just bump up your cam lift a little when your picking it out to compensate for the slightly shorter ratio on the Chevy rockers.

use big block chevy ! if your going to do it WRONG , do it 100% wrong , get a set of cheap china made rockers . do the wrong right

 

[torkair]

use big block chevy ! if your going to do it WRONG , do it 100% wrong , get a set of cheap china made rockers . do the wrong right

I totally have to agree with Dan here, roller rockers are all roughly the same price so you might as well do it right the first time. Chevy parts belong in chevy cars (or the recycling bin, but I'm biased). Clevelands, 351M/400s, and 429/460 engines use the same rocker arms and good used sets can be had for decent money.

Now for compression. If you're looking at around 9.5:1 with stock heads then swapping to a set of Aussie CC heads will render nearly an 11:1 compression which is pretty far into the special fuels range for iron heads.

 

[scrnic1]

use big block chevy ! if your going to do it WRONG , do it 100% wrong , get a set of cheap china made rockers . do the wrong right

Its the same damn part minus .003 valve lift, theyre even recomended by the rocker MFG's in some cases.

Ive been running them for almost 3 years now...Unless you can PROVE to me that there is a GOOD reason that i shouldnt run them, then im not wrong...Im not even the first person to have done this...Its a rocker arm...not rocket science

 

[scrnic1]

I totally have to agree with Dan here, roller rockers are all roughly the same price so you might as well do it right the first time. Chevy parts belong in chevy cars (or the recycling bin, but I'm biased). Clevelands, 351M/400s, and 429/460 engines use the same rocker arms and good used sets can be had for decent money.

Now for compression. If you're looking at around 9.5:1 with stock heads then swapping to a set of Aussie CC heads will render nearly an 11:1 compression which is pretty far into the special fuels range for iron heads.

Thats not fact...just bias. $199 is what I paid for the adjustable BBC roller rockers ina 1.7 ratio. Find me a NEW set of 1.73-1.8 roller rockers labled ONLY for the 351C,351M,400 ford for $199...I defy you to do so...If you do that, find me the technical data to support your bias, otherwise thats all it is blind Bias...