So lets start a discussion about small block heads

[RCCDrew]

Has anyone ever plugged the intake pushrod hole with a steel plug and redrilled the pushrod hole to aT/A style rocker?  You could then grind the hump out of the intake port. Would it be worth the effort?

[Chryco Psycho]

IMO no , I have done some serious port work on small block heads but the curve of the pushrod wall seems to create & venturii & speed air flow behind the valve , taking it out & I have come close doesn't seem to improve power on lower RPM street engines , it may be helpful if you are sustaining 8000 rpm in a Nascar type build

[AussieMark]

IMO no , I have done some serious port work on small block heads but the curve of the pushrod wall seems to create & venturii & speed air flow behind the valve , taking it out & I have come close doesn't seem to improve power on lower RPM street engines , it may be helpful if you are sustaining 8000 rpm in a Nascar type build

I agree the larger the intake port is the slower the air speed at low rpm and in a carbureted engine it can allow the fuel and air mixture to separate so you end up with puddles of fuel on the port floors which end up washing the oil film from the cylinder walls and eventually stuffing up the ring seal , sometimes you need to add material to increase the flow or just leave what is already there alone. Another no no is polishing the intake ports this reduces the turbulence which also helps keep the fuel and air mixture alive polish the exhausts but try and leave the intakes as cast.

[mrob]

The heads that Denison 636 mentioned may be P4876179. I have a set on my 414 340-based stroker. Judging by the dyno numbers, I think the advertised flow numbers are way optimistic. IMHO I think they flow around 230-240 cfm on the intake. Not bad, but in my case they limited the power output. They're also very hard to find.

[Denison636]

This is the only casting numbers on my head. I will see October 2 if they are any good. I am going to take my motor to a dyno. Just had a 416 done up that runs on E-85 pump gas.

[Denison636]

The above picture is the only casting numbers on the hole head. The numbers are located on the bottom side of the head.

[Denison636]

I can say that I love the cast iron heads I used. Made great power.

[Denison636]

Can anyone tell me anything about the head casting I have there. It's the only numbers on the head?

[brasil]

..my heads numbers are    2531894-B    and  AAWJ-340    are these heads  o.k ??

also my intake shows  a  3512100    should be a 71 intake right?

Greetings Juergen

[Strawdawg]

Can anyone tell me anything about the head casting I have there. It's the only numbers on the head?

I believe the casting numbers for heads is usually under the valve covers on top of the head.  Is that where that number is from? 

[Denison636]

No numbers there. This was on the bottom side of the close to the lifter valley. These were the only numbers on them.