302 E7 heads vs 289 C6AE heads

nellis003

nellis003

Senior Member
Hi all,

Continuing the planning on building my 87 5.0 HO engine...

I have two sets of heads. One pair has "C6AE" cast underneath and appear to be older 289 heads. I also have the E7 heads that came off the block I'm using.

I've heard that the 289 heads flow better because they don't have the little emissions bump inside the exhaust chambers. I've also heard that the compression is a little better on these heads.

I'm not really building the engine for high performance, but if I have parts available that are better to use, then I'd rather use them. So, considering that I have these heads already, should I use the 289 heads rather than the original E7's?

On a side note, does anyone know if the stock valves are interchangeable?

I'm planning on leaving it as a fuel injected engine, in case that makes any difference.

Thanks for any opinions,
Nick
 
nellis003 said:
Hi all,

Continuing the planning on building my 87 5.0 HO engine...

I have two sets of heads. One pair has "C6AE" cast underneath and appear to be older 289 heads. I also have the E7 heads that came off the block I'm using.

I've heard that the 289 heads flow better because they don't have the little emissions bump inside the exhaust chambers. I've also heard that the compression is a little better on these heads.

I'm not really building the engine for high performance, but if I have parts available that are better to use, then I'd rather use them. So, considering that I have these heads already, should I use the 289 heads rather than the original E7's?

On a side note, does anyone know if the stock valves are interchangeable?

I'm planning on leaving it as a fuel injected engine, in case that makes any difference.

Thanks for any opinions,
Nick
Click to expand...

The C6 (1966) heads are probably better performance wise. The "E7" (1987) are probably lower compression smog heads.
 
Spend some time with a dremel and port match the exhaust. They are very restrictive in stock form and a little work helps immensely.
 
Dave72dt said:
Spend some time with a dremel and port match the exhaust. They are very restrictive in stock form and a little work helps immensely.
Click to expand...


If the 289 heads are higher compression and already have the unrestricted exhaust port, is there any advantage to porting the E7 heads and using those instead?

Thanks for the input so far.

Nick
 
I would think the seats in the late model heads may be either hard steel or hardened cast to last longer. The valve seats in the early heads usually didnt last all that long. A little time spent with a dremmel or a die grinder is well worth the effort and time. It goes much fatser than you think and is very rewarding.
 
Even the "unrestricted exhaust ports" are restrictive. ALL factory SB heads, including the hipo's can benefit from the porting.
 
www.fordmuscle.com has some really good home porting articles for your E7 heads.Best bet is look for a set of GT-40's and and use those, average price for some in good shape $250-$350 a pair they are better than either head you have and will work with your present roller cam.
 
The 289 heads aren't made for unleaded gas, the seats are not hardened nor are the valves. The valve springs won't work with the roller lifters in your HO block, they aren't strong enough and will bind. A C6..head used rail type, non-adjustable rockers, my guess, you would have to buy a custom made push rod to make the valve lash correct. Both 289 and HO heads are restrictive in the exhaust ports, like the others said, a die grinder will solve that problem. Keep what you have and do some port grinding. Remember, the HP 289 was advertised at 271 horsepower and I guarantee that a HO 5.0 will literally blow the doors off one in a similar weight car
 
Great information, thanks to everyone who weighed in.

I'd love to get a pair of GT40 heads, but I'm trying to keep the build as low budget as possible, so unless I can find someone who will trade me a set for some other parts I have, I'll probably port the E7 heads and go from there.

Hadn't even considered the valve seat issue, so thanks for that point of view. I'll put the 289s back on the shelf for now.

Thanks again,
Nick
 
The Explorer heads are a straight plug head and use a different header flange. They flow the best and are very cheap at the junkyards but you need custom headers or at least a new flange for your old ones. Some guys have said you can rework the oldre header flange to fit the Explorer heads.
 
You dont need a custom header for a GT-40 head. Now the GT-40P head you do. I'm running a E7 head on a 72 model 302 with no problem. I have a set of 69 and 70 heads that I was going to use until I got a good deal On the E7's. There is alot of info on the E7 heads, just google ford E7 heads.
 
You must log in or register to reply here.
Back
Top