[Karch]

Look at Jon Kaase and the EMC. He had some very small chambers for the pump gas combo, and it was very efficient.

[Steve C.]

Don't forget, much differant chamber design on the heads used by Kasse. Plus he was way pushing the envelope on compression.

(and presumably with coatings on pistons, etc. ?)

[70KGOLD]

I’m no stranger to detonation and walking home. I remember the first time I bolted a set of # 48 heads on my 75 400 engine. It was late Saturday night when I got the car running. I left my driveway sideways leaving black marks for quite a distance. After running a stock 75 400 for years, this was great. But then it started happening. Within 40 min of leaving my garage the temperature hand was pegged out and the death rattle was getting louder and louder. I did make it home that night but not before blowing a head gasket and pretty much toasting my engine. That was several years and head gaskets ago. The #48 heads are now on my 455. I can idle in traffic for hours, and run mid 12 at the drag strip but for some reason my MPH is low around 103.

That’s why I would like to try a new combo using a 400 stroker engine with the e-heads. From what I hear they flow much better than a cast head and that may be my problem, the 48 heads just chokes the 455 out on top end. Also shouldn’t the e-head dissipated heat better therefore allow more compression? I thought a 72 cc head on a 400 would make around 10.5 but you guys are saying 11.5?

[Skip Fix]

Here is Steve's dish pistons. Mine are similar.

[Steve C.]

A common piston size with a 4.250 stroker crank is 4.185, using these with a true 72cc chamber, a flat top piston with 6.7 cc valve reliefs, .040 thick gasket and zero deck for piston height and you have about 11.93:1 compression. Your actual compression will vary.

[b-man]

Originally Posted by 70KGOLD

I’m no stranger to detonation and walking home. I remember the first time I bolted a set of # 48 heads on my 75 400 engine. It was late Saturday night when I got the car running. I left my driveway sideways leaving black marks for quite a distance. After running a stock 75 400 for years, this was great. But then it started happening. Within 40 min of leaving my garage the temperature hand was pegged out and the death rattle was getting louder and louder. I did make it home that night but not before blowing a head gasket and pretty much toasting my engine. That was several years and head gaskets ago. The #48 heads are now on my 455. I can idle in traffic for hours, and run mid 12 at the drag strip but for some reason my MPH is low around 103.

That’s why I would like to try a new combo using a 400 stroker engine with the e-heads. From what I hear they flow much better than a cast head and that may be my problem, the 48 heads just chokes the 455 out on top end. Also shouldn’t the e-head dissipated heat better therefore allow more compression? I thought a 72 cc head on a 400 would make around 10.5 but you guys are saying 11.5?

In your opening post you mention '400 stroker'. A 400 stroker with the commonly available 4.25" aftermarket stroker crank is now essentially a 455 engine after you add the bigger stroke, so yes it will be close to 11.5:1.

A 400 using a 3.75" stroke 400 crank is close to 10:1 with the 72cc E-heads. One is a 'true' 400, the other is not even close to being a 400. Two different engines, built off the same 400 block.

Aluminum heads do dissipate heat, but that dissipated heat is power lost. You must up the compression (by 1/2 to a full point) and the headflow a bit with aluminum heads just to equal the power of iron heads.

Of course the E-heads are a higher flowing head out of the box than most race-ported iron heads, so you're ahead in that respect.

[roadrage david]

im not sure if i remember correct but when MR-Pbody build my 461 stroker with srp flat top pistons he used edel 87cc heads, afther mesuring them they proved to be 85cc!.. and my engine hase 10.1 comp. did you guys measured your 87cc heads as wel.....

[Geoff]

I have 34cc dished pistons in my 455, with a D shape dish. With milled #16 heads, my CR is a true 10:1.
I expected the more compact chamber shape would require a little less timing than the usual 34-36 degrees that 455s usually like, so I set up the dist for 32 total.
Wrong!!
On the dyno, it made best hp with 29 degrees, & it made 16 rwhp more just retarding the timing from 32 to 29.