351C Head Casting D3ZE-AA?

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wrobinson

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My 13 year old wants to build a 1971-73 Mach 1 Mustang for his first car. We have found a Grabber Blue with white interior base model 1971 Mach 1 to start on.
My Lord, I have read so many contradicting things about these heads. I would like to use the original heads in my build. Can these heads be modified to perform decently for a well built daily driver? If the heads have the small 2.04 or 2.05 intake valves do you think stepping up to a 2.08 or 2.09 valve will help? I am not shutting for the stars just around 375hp.

 
You should be able to reach that goal with stock heads and the right supporting mods. My head flow chart shows the 2v Cleveland heads flowing right at 200 cfm intake up to .600" lift so the cylinder head airflow shouldn't hold you back. As a general rule of thumb you can make 2 horsepower for every cfm on the intake side so they probably won't hold you back.

 
I have stock 351C-2V heads on mine, and between the go-fast goodies I built into my engine, the CamQuest utility from CompCams says I should expect around 400 at the crank. My seat-of-pants dyno says I'm probably pretty close.

Click on the "Visit My Garage" button below to see what I went with to get there. Mike's right - opening those valves up a little more will get greater airflow, but you're going to want better springs, push-rods, lifters, and maybe even a higher ratio rocker arm (1.7 vs. 1.6) to get that extra CFM and add some strength and reliability to the new mix. Consider upgrading to new 1-piece valves as well.

Getting a mild port & polish on the heads won't hurt either.

Hope that helps!

 
Don't listen to any of the naysayers on these 4V heads. They are in fact great heads and very underrated. I think the reason they've been given a bad wrap is because they came out in the pollution era and performance numbers dropped, but what most don't think about numbers wise is that horsepower numbers went from gross to net as well which showed lower numbers.

I was one of those many years ago that thought the same as everyone else about these heads until I was put right about them 15 years ago. The Cleveland heads are to this day still very misunderstood and most think that the 70-71 closed chambered heads are the only way to go. If hunting for big compression they are great, but on the majority of true street engines they're not really needed and open chambers are quite suffice. Same goes with 2V heads, people think the 302 closed chambered heads are needed and the biggest mistake with them is people fitting 4V valves into them. In fact a lot of engine guys here in Australia that know about Clevelands are using open chambers and milling them to suit with standard valve sizes on street strip factory cast iron head 2V engines. In fact I haven't used a 4V valve in 2V heads since the early 90's (when I learnt they were too big for them) and discourage people using 2V heads with 4V valves already fitted.

Open chambers and 2V valve sizes (in 4V heads especially) were given a bad wrap for many years, basically since they were made and now are finally starting to be proven wrong. Rumours probably started by Chevy guys and as soon as I hear people talking about setting Clevelands up like you would a Chevy (and I hear it plenty, even on places you'd expect to know better) I just know they really do not truly understand the Cleveland cylinder head design. It's one of the reasons I don't get on public forums and speak much about these awesome engines, as there's those that know everything and refuse to listen to facts. I only came on here to say about how great these heads truly are as I don't want another guy being lead to believe they are garbage heads and need to use closed chambered 4V's for their street, even street/strip application. Put it this way, I'm using these garbage 4V heads on my new build for my vert and another set being used on another build I'm helping with and open chamber heads on a 2V that's just been completed. So we'll see how crap these heads are next year when I build it as I'm just parts gathering until I pull the driveline out next June.

All the best with your build and hope it all works out well for you. I hope this helps with your decision in using your original 4V heads, so no need to be discouraged in doing so. One great piece of advice is to use an machine shop that has a lot of experience doing Clevelands.

Good luck

Jason

 
Don't listen to any of the naysayers on these 4V heads. They are in fact great heads and very underrated. I think the reason they've been given a bad wrap is because they came out in the pollution era and performance numbers dropped, but what most don't think about numbers wise is that horsepower numbers went from gross to net as well which showed lower numbers.

I was one of those many years ago that thought the same as everyone else about these heads until I was put right about them 15 years ago. The Cleveland heads are to this day still very misunderstood and most think that the 70-71 closed chambered heads are the only way to go. If hunting for big compression they are great, but on the majority of true street engines they're not really needed and open chambers are quite suffice. Same goes with 2V heads, people think the 302 closed chambered heads are needed and the biggest mistake with them is people fitting 4V valves into them. In fact a lot of engine guys here in Australia that know about Clevelands are using open chambers and milling them to suit with standard valve sizes on street strip factory cast iron head 2V engines. In fact I haven't used a 4V valve in 2V heads since the early 90's (when I learnt they were too big for them) and discourage people using 2V heads with 4V valves already fitted.

Open chambers and 2V valve sizes (in 4V heads especially) were given a bad wrap for many years, basically since they were made and now are finally starting to be proven wrong. Rumours probably started by Chevy guys and as soon as I hear people talking about setting Clevelands up like you would a Chevy (and I hear it plenty, even on places you'd expect to know better) I just know they really do not truly understand the Cleveland cylinder head design. It's one of the reasons I don't get on public forums and speak much about these awesome engines, as there's those that know everything and refuse to listen to facts. I only came on here to say about how great these heads truly are as I don't want another guy being lead to believe they are garbage heads and need to use closed chambered 4V's for their street, even street/strip application. Put it this way, I'm using these garbage 4V heads on my new build for my vert and another set being used on another build I'm helping with and open chamber heads on a 2V that's just been completed. So we'll see how crap these heads are next year when I build it as I'm just parts gathering until I pull the driveline out next June.

All the best with your build and hope it all works out well for you. I hope this helps with your decision in using your original 4V heads, so no need to be discouraged in doing so. One great piece of advice is to use an machine shop that has a lot of experience doing Clevelands.

Good luck

Jason
Jason,

This is my first rodeo with a Cleveland engine. Actually this build is for my 13 year old son to become his first car. I just finished a 1978 Trans Am for my oldest son, Rigell. That is the reason why performance expectations are low for the build. I would like the car to be able to run some 13's in the quarter mile while being dependable and pump gas friendly. My plans are to increase compression to around 9:1, choose a good camshaft with low to mid 500 lift and less than 280 advertised duration(hydraulic or hydraulic roller), and good aluminum dual plane intake. The heads will be treated to performance 3 angle valve job, new hardware to support camshaft, surface cut, and mild port and bowl work. It may get closer to 400hp before it is over.

 
This is my first rodeo with a Cleveland engine. Actually this build is for my 13 year old son to become his first car. I just finished a 1978 Trans Am for my oldest son, Rigell. That is the reason why performance expectations are low for the build. I would like the car to be able to run some 13's in the quarter mile while being dependable and pump gas friendly. My plans are to increase compression to around 9:1, choose a good camshaft with low to mid 500 lift and less than 280 advertised duration(hydraulic or hydraulic roller), and good aluminum dual plane intake. The heads will be treated to performance 3 angle valve job, new hardware to support camshaft, surface cut, and mild port and bowl work. It may get closer to 400hp before it is over.
Your expectations of achieving your 1/4 mile times on less than premium gas are a little optimistic in my experience . You really should run a minimum of around 9.7 compression and a minimum of 3.50 gears and premium gas to get close to your goal and 3.73 gears would be better . I would also use the bigger valves if you use those heads but if it were mine I would use big valve closed chamber heads and almost 0 deck it then set the quench/squish to around .036" with custom 4032 material pistons from racetec that mirror the combustion chamber . I would also have the heads lightly pocket ported by a knowledgeable cleveland guy . use stainless valves with hardened tips or one piece stock type valves but back cut the intakes . if you want a semi stock looking engine, the blue thunder or scott cook aluminum intakes are 2 good choices.

Compression is king and the less compression you run, the higher you have to spin an engine to get the same 1/4 mile number which means longer duration cams which further reduces compression which further reduces low end power.

Having a tight quench/squish clearance allows you to run a little higher compression without increasing the potential for detonation.

Below are the results from one magazines drag test of a 1971 boss from 1971 and they had around 10.0 compression . Of coures if they had mickey thompson et drag radials on it, it would have gone slightly quicker.

4spd, 3.91, 0-60 - 5.8, 1/4 mile - 13.80 @ 104mph

 
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This is my first rodeo with a Cleveland engine. Actually this build is for my 13 year old son to become his first car. I just finished a 1978 Trans Am for my oldest son, Rigell. That is the reason why performance expectations are low for the build. I would like the car to be able to run some 13's in the quarter mile while being dependable and pump gas friendly. My plans are to increase compression to around 9:1, choose a good camshaft with low to mid 500 lift and less than 280 advertised duration(hydraulic or hydraulic roller), and good aluminum dual plane intake. The heads will be treated to performance 3 angle valve job, new hardware to support camshaft, surface cut, and mild port and bowl work. It may get closer to 400hp before it is over.
Your expectations are a little optimistic . You really should run a minimum of around 9.7 compression and a minimum of 3.50 gears and premium gas to get close to your goal and 3.73 gears would be better . I would also use the bigger valves if you use those heads but if it were mine I would use big valve closed chamber heads and almost 0 deck it then set the quench/squish to around .036" with custom 4032 material pistons from racetec that mirror the combustion chamber . I would also have the heads lightly pocket ported by a knowledgeable cleveland guy . use stainless valves with hardened tips or one piece stock type valves but back cut the intakes . if you want a semi stock looking engine, the blue thunder or scott cook aluminum intakes are 2 good choices.

Below are the results from one magazines drag test of a 1971 boss from 1971 and they had around 10.0 compression.

4spd, 3.91, 0-60 - 5.8, 1/4 mile - 13.80 @ 104mph
I was actually leaning toward the blue thunder or Scott Cook intakes for their original appearance and performance. I will settle for whatever the HP output is once completed but more over than not it will be a mild build. If it were for me stock appearing 408 with all the goodies but I do not believe for a first car it will be needed. The gear ratio is currently a 3.50 with traction lock.

 
I modified my post a little before I saw your reply . Please re-read it.

What trans are you using?

I wouldn't spend the money on a roller cam for the 73 heads . A good hydraulic with crane anti pump lifters will do a nice job.

This is one of many cams that would work well

http://www.lunatipower.com/Product.aspx?id=1623&gid=287

 
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I feel your goals are very achievable providing the drive train is matched to the engine build. The link below will take you to a long post from the Pantera forum that you may find interesting. Let us know which way you decide to go. Chuck

http://pantera.infopop.cc/eve/forums/a/tpc/f/5650045562/m/4591090956
Wow! That was a great read. The information in that article is incredible. So my idea of adding the 2.09 BBF intake valves to the D3ZE was kind of on track. I said 9:1 static compression and they recommended 9.25:1 compression. I certainly appreciate you sharing that information.

 
I modified my post a little before I saw your reply . Please re-read it.

What trans are you using?

I wouldn't spend the money on a roller cam for the 73 heads . A good hydraulic with crane anti pump lifters will do a nice job.

This is one of many cams that would work well

http://www.lunatipower.com/Product.aspx?id=1623&gid=287
That grind is right in line with what I am wanting to install, thanks.

 
Wow! That was a great read. The information in that article is incredible. So my idea of adding the 2.09 BBF intake valves to the D3ZE was kind of on track. I said 9:1 static compression and they recommended 9.25:1 compression. I certainly appreciate you sharing that information.
the 2.09 valves are a happy medium but you really should get some pocket porting done to get the most benefit from them . this should include just a little work on the short turn radius on the intake.

 
Wow! That was a great read. The information in that article is incredible. So my idea of adding the 2.09 BBF intake valves to the D3ZE was kind of on track. I said 9:1 static compression and they recommended 9.25:1 compression. I certainly appreciate you sharing that information.
the 2.09 valves are a happy medium but you really should get some pocket porting done to get the most benefit from them . this should include just a little work on the short turn radius on the intake.
All very good points that will definitely be embraced during the engine overhaul. I guess until I get the motor apart I do not really know what I am working with.

 
Wow! That was a great read. The information in that article is incredible. So my idea of adding the 2.09 BBF intake valves to the D3ZE was kind of on track. I said 9:1 static compression and they recommended 9.25:1 compression. I certainly appreciate you sharing that information.
the 2.09 valves are a happy medium but you really should get some pocket porting done to get the most benefit from them . this should include just a little work on the short turn radius on the intake.
All very good points that will definitely be embraced during the engine overhaul. I guess until I get the motor apart I do not really know what I am working with.
there are also some oil system mods that i would do and others wouldn't

 
Great find on the info Chuck, well done and thanks for posting up. I've always meant to have a look on the Pantera forums, but haven't for some reason or another maybe because I just can't be bothered too much these days. George Pence is a very good source for the Cleveland engine, but some of his ideas are very outdated. Don't get me wrong they still apply in certain circumstances, I don't know how old that post was, but talking about doing seats with stones is early 90's latest, at least that was the least time I'd seen a set being used. That write was a great source for people that don't fully understand the Cleveland head design to give them a good insight into the 4V being designed the way it was by Ford. As was said, it was not unintentionally made that way.

Back to the OP, your goal of 400HP is very achievable with this engine with these heads and even with a decent hydraulic cam if that's what you wanted to use. The Blue Thunder is a very good intake, but the Scott Cooke is the better one again and best part it looks totally stock from the outside as well. The downside of it though is price, but as we all know, performance costs. Also oiling mods are not really necessary on a build like this and in fact not really needed on a Cleveland unless revving it over 6500-7000 RPM+. The only real oiling mod I'd think worth doing on any Cleveland build up to those revs are a decent sump with increased capacity and possibly a windage tray. Also with the oil pump just a standard mellings pump and go through it properly, including the pressure relief valve as these have had dramas in the past. As I said previously find a shop with experience in Cleveland engines for any type of machine work. All the best with it and if I can help in any other way, just send me a PM.

Jason

 
oiling mods will be extra insurance against premature wear and possible failure . they also have ZERO downside . i have been building clevelands and other engines since 1971 and i do this for a living.

 
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heres how that lunati cam will sound with similar exhaust.


 
that cam made almost 300 rear wheel hp with 10.5 compression but he didn't say what type of dyno it was.


 
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