New big block head?

[karki]

If you have a 8.7:1 compression, .030" over 383, and you take off a 84cc head and bolt on the 75cc head you will go to 9.4:1 compression. If you take off a 88cc head you will gain a full point of compression.

Though the E-Sreet head is the same casting as the RPM head, is is NOT hand blended in the runners under the seat as the RPM head is and is not CNC'd in on the intake entrance and the exhaust like the RPM head.

Tech couldn't tell me the shape of the combustion chamber when I asked yesterday.

Even though they use the same size valves (2.14/1.81), they use cheaper, heavier valves, lighter valve springs, and harder valve seat inserts in the heads. Because of these design changes they are not ment to be used in high performance (racing) applications. The harder seats will tend to cause valve bounce at high rpms but should last longer in street driving conditions. The lighter springs and heavier valves limit the rpms to about 5500.

You still are required to THINK about what you intend to do in the future with your engine build. It may be a great stock head replacement for street driving but is not ment to be a race head. You may be able to force it that way if you replace the seat inserts, valves and springs.

But, if you want a 75cc head for racing, get the Victor.

So lets say im thinking on putting a comp cam XE285 in my 383 and put that head on it wont work even if i change spring to comps recomendation?

could something broke or will it just not giving the power that the eddy rpms should? // peter

 

[IQ52]

Peter,

I haven't been able to get my hands on one of these heads to flow test it, so how it will compare to the RPM head power wise, I cannot say. It has the same port shape as the RPM I'm told, so even if it is not hand blended as the RPM it should equal or better the Stealth head. I personally think you would be just fine to change the springs and run this head on your 383 with the XE285HL. I know I would sure try it. If you can call Edelbrock's tech line you may get a more definitive answer.

 

[karki]

Peter,

I haven't been able to get my hands on one of these heads to flow test it, so how it will compare to the RPM head power wise, I cannot say. It has the same port shape as the RPM I'm told, so even if it is not hand blended as the RPM it should equal or better the Stealth head. I personally think you would be just fine to change the springs and run this head on your 383 with the XE285HL. I know I would sure try it. If you can call Edelbrock's tech line you may get a more definitive answer.

Ok thanks , its great whit 75c/c when im running flat top pistons // peter

 

[rumblefish360]

IQ, just a comparo between the Victors and the Stage VI's and prices.

 

[wedge5]

So now do we have a new weapon for the low compression big block? Edelbrock is now advertising a 75cc combustion chamber E-Street aluminum head for the low compression engines. Is this a good alternative to the 915 that is getting harder to find? They are listed on Summit Racing's website for $979.95/pair. Hello Stealth heads, are you watching? You have competition.

Are you sure that is for the pair? When I looked it didn't say pair or each so I was wondering why you wrote "pair".

 

[IQ52]

It is for the pair.