Aluminum heads worth it?

[Napoleon1991]

I'm looking into the possibility of upgrading the stock 452 heads on my 440 to aluminum heads. I was looking at the edelbrock E street 5093 heads. The motor is pretty mild, has about 9.7 CR, TTI headers, performer intake and currently has a comp XE268h cam in it. Car has 3.23 gears and a 2500 stall convertor. Car runs great and pulls hard, but I was wondering if there would be a noticeable performance gain by changing heads.

 

[HEMI-ITIS]

If you could pick up 50 HP would you "feel" that? Runs great and pulls hard?? Leave it alone

 

[Kern Dog]

It has been popular to just say that the aluminum heads are "cheaper" in the long run.
I'm not so sure about that.
Maybe the people that believe that for certain had really bad heads that needed extensive work to be serviceable. I've had great luck with BIG block iron heads. I've only needed minor surfacing and a valve job to get them working. I've ran into several cracked small block heads though.
Now, if you are looking for a 25-40 HP bump on a basically stock engine, the aluminum heads DO flow better and will provide that.

 

[Napoleon1991]

Thats a pretty significant gain from just swapping heads. I put all of the engine specs into camquest (for whatever thats worth) and it showed a 70hp gain from just switching heads. Seemed way to optimistic to me, so i wanted to get a second opinion here.

 

[Kern Dog]

Well, cam and compression are the variables. MORE of both and the gains will be bigger, just as it is with cast manifolds VS headers.

 

[threewood]

50 hp gain should be noticeable, right?
If you have the $$ to burn go for it.

 

[Napoleon1991]

Should compression ratio be increased when swapping to aluminum?

 

[rumblefish360]

Should compression ratio be increased when swapping to aluminum?

It can be not Necessarily should be. But for what it’s worth, at your stage for the build, I would not do aluminum heads.

 

[1 Wild R/T]

Should compression ratio be increased when swapping to aluminum?

If you have a true 9.7 now you should be experiencing detonation unless you have access to better than average fuel...

452 heads have 88-92 cc chambers, edelbrock E street 5093 heads show a spec of 84cc chambers so you'll be right around 10-1 which should be plenty...

 

[Napoleon1991]

I do have some detonation problems. I run 93 octane and if i set total timing any higher than 31, it will ping

 

[1 Wild R/T]

I do have some detonation problems. I run 93 octane and if i set total timing any higher than 31, it will ping

In that case bolt on a set of E streets & crank in some timing... One thing, what pistons are in your engine? If they have quench pads s the E streets won't work..

 

[tnfastback]

If you don’t care about the look and you want to know what pull hard feels like put that thing on the bottle. Cheaper than aluminum heads and way more fun. A good 125 system and good tune won’t hurt a thing.

 

[Napoleon1991]

In that case bolt on a set of E streets & crank in some timing... One thing, what pistons are in your engine? If they have quench pads s the E streets won't work..

Flat tops with valve reliefs. What are quench pads?

 

[Kern Dog]

Quench pads were a design of piston with a raised section on them to induce quench in an opened chambered head.

 

[rumblefish360]

AKA - A dome.

 

[1 Wild R/T]

AKA - A dome.

Yes but different from. most domed pistons... The dome typically is intended to fit into the wedge shaped area around the valves.... A quench pad is designed to fill the open chamber area opposite the wedge shaped area around the valves....

Since the Edelbrock heads are closed chambered a quench pad piston would collide with the head...

 

[no way dave]

Isn't the general rule of thumb is you can get away with an extra point of compression with aluminum. So if you're willing to take that chance and save 60 or so lbs off the front end, go for it.

 

[1 Wild R/T]

Isn't the general rule of thumb is you can get away with an extra point of compression with aluminum. So if you're willing to take that chance and save 60 or so lbs off the front end, go for it.

As a general rule yes... He also may/likely will be picking up useable quench so in theory he could maybe get another .5 point... But he was pinging before when he cranked in timing so he is on the ragged edge and the Edelbrocks have smaller chambers so the C/R is already going up.... He'll have more HP & a very safe pump gas street friendly combo.... If your not racing why push it?

 

[BSB67]

Flat tops with valve reliefs. What are quench pads?

Do you know the specifics of the piston?

 

[HEMI-ITIS]

When you have the hunger for more power it can be an endless quest. If it is a street beast and you want a little more kick nitrous is the least expensive. When you think about well flowing heads,you might need pistons to make the upgrade work well. Then if the engine is apart maybe a little more stroke,,,,then a cam and lifters that might require new springs,,,,,the you you might want more and more!!
Take it from an addict,it's never ending unless you set goals and can be happy with that.
I am driving my childrens inheritance .
My goal is 8.50 and that is IT!! I can't do what I used to because getting old SUCKS!!