Svo Aluminum Head Application ???

[ronzara]

Guys,
I just found a NEW set of Motorsport SVO Aluminum Heads (M6049X302). >>>>BARE HEADS

Does anybody know if these will work with my 1973 351W block????

The Ford Performance site mentions Roller Camshaft, but I am using a Hydraulic Soild Lifter Cam.... Is this a problem?

Combustion Chambers are 64cc. Would anyone recommend shaving them, say .10, to get the ratio higher with stock pistons??

The Intake valves are 1.94 and exhaust is 1.54, I think this should would with my stock pistons, given I don't go over .500 lift right? >>
my cam specs are: advertised duration = 265 273 @.050 = 211 223 lift = .472 .486 110 Lob Sep
With heads shaved .10 wouldn't this make the cam lift .482 & .496?

Sorry about all the questions, but I just want to be sure I am heading in the right direction before I spend all the cash.


ALL INPUT WILL BE APPRECIATED!!

Thanks,
RZ

[DAVID GAGNARD]

Do not know about these heads,I'd have to check my SVO book,but add up the cost of valves,springs,retainers,guide plates,screw-in studs and they might not be as good a deal after all....You'll have to put the numbers on paper and see how you come out,if they work and if the additonal parts are not too expensive,they are defianately better than the iron heads.... But if you want a street cruiser,there is nothing wrong with rebuilt/reworked iron heads.....

Just my .02 cents on the matter....

David

[750hp]

Ron,
These heads will give a moderate performance improvement for your engine. The weight savings will be nice, and you'll probably pick up a real-world 40hp with them (over standard iron heads).

They use a standard bolt-on rocker, so you won't have to machine them for screw-in studs.

Like David said, you might have second thoughts about these heads when you price up all the extras. Depends on how cheap you can get these heads, it might be worth waiting for some omplete Edelbrock Performer RPM, or the 165 Canfields. It's usually a better deal to get the heads fully assembled, with the spring rates to suit your camshaft.

A couple of things :

Machining the heads doesn't affect your camshaft specs. Reducing the chamber volume of the heads increases your compression ratio, but your camshaft lift/ratio/duration all stay the same. Changing rocker ratio affects your overall camshaft lift. Your engine capacity also remains the same.

Camshafts are either roller or flat tappet style. In each of those styles, you can have either hydraulic or solid lifter style.

[DAVID GAGNARD]

If Craig's estimate of a 40hp increase (and I have no reason to not believe him),then IMHO they are not worth it if you already have the iron heads.....For instance, I have the same iron heads that you have when building my motor.... Being a scrounger and having access to a machine shop does help.... Got my heads milled and tapped for screw in studs---free,did the valve job myself-free,traded out some work with a buddy who spent approx. 24 hours of work porting-polishing-bowl blending and gasket matching the heads,again free,traded out some body work to him on his late model mustang....

Had to pay a shop to put in new valve guides,do not remember but it was not that much.... Machinist was looking over the heads and said the work was top quality,but said with all that work I probably would only gain 40 to 50 hp....I was floored,did not think it would be that good... He has a lot of expirience with dirt track motors and dynos and has done a lot of expirementing with heads and intakes so I trust his judgement.....

My point is,the old iron heads can be made to work rather well when reworked,if you had to pay or source out all the work it would not be cost effective,new aluminum heads would actually be cheaper,but if you horse trade and can do some of the work yourself,you can build a really good set of heads fairly inexpensively.....Around here the C-9 and D0 heads can be bought for as little as 50 bucks per PAIR.... I have three or four sets in my shop that have been there for 10 years or more and would gladly let someone have them for 50 bucks a pair,take your pick. I really do not need them and they are just taking up space....

For a street car, anice set of iron heads will be more than adequate for your car,serouis racing would be different....
Again,just my .02 cents on the subject....

David

[ronzara]

I've got the Bare heads, brand new (never bolted on) with mild porting and Blending for $400.

They run $799 and up in parts catalogs. Looks like the valve train kit is another $350 of so........... I will have about $800 total in the heads.

Should I keep em or not????

Thanks
RZ

[DAVID GAGNARD]

RZ;

If your talking about dollars and cents,then figure how much it would cost to get your iron heads to equal the aluminum heads,probably more.......For that price I would keep the aluminum heads.....BTW,the aluminum heads can be taken a lot further than the iron heads and you can run more compression with aluminum.....

David

[750hp]

I'm with David here - for $400 I'd keep them, providing the portwork already carried out is just a very basic portjob. You did mention that was the case, so it should be fine. You can usually tell pretty easily if someone has "overported" a set of heads to the point that the flow numbers are often WORSE than a standard set.....

Ally heads do look good in any engine bay... Congrats on your purchase !