SC heads on N/A motor

Rodeo Joe

SCCoA Member
Are there any advantages/didadvantages to using these heads on my 97 3.8 n/a T-bird? I know they are supposed to be stronger to handle the boost from the supercharger, but other than that, anything? Any differences in compression? I'm gathering up parts for a P+P head and intake swap and have seen people selling these. Just wondering if they would be worth getting for what I'm planning on doing. I'm staying n/a. Thanks.

Joe
 
im not absolutely positive but i dont think all the passages will line up. the supercoupe block and heads were completely redesigned from the 3.8 n/a.
 
From what I researched the main difference between early 3.8 heads and SC heads were strenght. Both flowing the same..The 97 3.8 stang heads ar esuppossed to be just as strong and use lighter valvetrain componants...So you would not get any improvement using SC heads..Of course This is what I had researched..Never compared them side by side
 
Sc heads will work.

All of the passages and what not will work. Changing the Cooling and oiling passages would have required a rework of the block.

The heads are stouter and can handle the rigors of the supercharged world better than the N/A heads can. I don't know the size comparisons of combustion chamber size SC/n/a. Nor do I know valve diameters either comparing both heads.

Intake and exhaust manifolds should bolt up fine. I think that the only real change that was made to the SC heads Vs. N/A was that ford added material in the castings for the cooling passages to stiffen the heads up. Of course this slightly impacts the cooling capacity of the heads.

What I would suggest is you either take two routes. If you can get a set of SC heads cheap, make sure to have them P+Ped real good. But have them done for a N/A enviroment (good intake tumble and swirl, velocity)

Now another option would be to use the Split port heads from a 99+ 3.8 Mustang. In order to use those you will need the split port intake. I think injectors from the Mustang will work, but you might have to do custom work on the fuel rails to make it fit.

The split port design is great for both low end torque and high end HP. Exhaust ports are smallish, and even with extensive porting only yeilds minimal results but then again, you are not inducting as much on the intake side either.

One member here named "gaston" has done this swap and then plopped a Vortech on it. Making in excess of 400hp in his mustang. He might be able to offer more insight. Don't give up though, I seriously think that a great high winding 3.8 (or 4.3) stroker is possible in these engines. Especially if the owner does great work to carefully balance everything and reduce rotational mass.... Good luck and report back often if you do decide to use S/C heads.
 
Thanks guys!

I've seen SC heads available and thought they might be a good idea. I'm planning on doing the heads up while I'm still driving the car so I have no down time. If I can find a set of 96 and up heads I might consider those. So i figured if the opportunity came and I found a set of SC heads I wanted to know what I was looking at first before I did. I've thought about the split port swap. Still leaning towards the single port route though.

Joe
 
If you want single port....

Then go with the S/C heads. They are stronger and should bolt up. But like I said, whether you get 96+ N/A heads or 89-95 SC heads, you'll want to get them worked on very well. Coy Miller does a great job porting but there are also other companies like Steinmeyer (I think that is there name) and other members here do professional porting and polishing.

IF Keeping things N/A you'll want to concentrate on reducing valve train mass, this means lightweight springs, retainers, valves, rocker arms and pushrods. This will allow the engine to rev freer past 7000rpm (plus considering reducing mass of bottom end components with good balancing). That is where most N/A engines are going to need to make their power (proper cam needed too).
 
When I was getting ready to get my motor together, I took the heads (90 SC heads) to my machine shop and we compared them to a set of N/A 3.8 Mustang heads sitting there. Not a thing is different, all the ports are the same, same valves, etc. etc. Only difference is the strength. They are made in different countries and made out of different aluminums. If your keeping the motor N/A (or going with nitrous), check out getting the heads milled. Taking .015" off will raise the compression a little bit...I did this with mine (trying to get more power in outher areas without changing the blower pulley for now :)) The ports on them open up very nicely though...Gasket matched mine and they are very nice :)
 
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