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The Heads
The heads chosen for this build were Indy's 440-C heads. Why? Well the class this engine is in, they have to run a Iron head. The debate went on from 906, 452 or 915. A fully ported head from stock in the right hands can make some serious power. But durability is compromised severely. We wanted something that would last a while before it needed to be replaced. Indy was really the only choice here, and now that they have stopped making then, its only going to be harder to get them.
These heads were NOT PORTED!!!!! I took the 80# chunks of iron, cleaned up a few casting boogers installed a good set of 2.20/1.81 valves w/back-cut and called it good. Remember its only 470 ci and the rpm band is only going to go to 7500rpm. We also have a nice 1.7 to 1 rod ratio and that will work very well with these intake port volumes. BIGGER IS NOT ALWAYS BETTER!!! Porting these heads would have got more power for sure, but the truck its going in is not set up for 900hp. In due time it may be. Plus to get that kind of power, the RPM band is shifted way up there and now you have to look at reliability and maintenance. Its all a balancing act.
Mr Gasket Ultra Seal MLS head gaskets were used and are Guaranteed not to leak FOR LIFE! And they did not leak a drop on the dyno.
No port work here! Exhaust side.
 Or here! Intake ports.  | |
The Intake
On the intake, I can not tell you how many times I have heard "You have to run a Indy intake with Indy heads". BULL! As you can see here, this is NOT an Indy intake, rather a Victor from Edelbrock.
Why in the world would you run that you ask? A few reasons. I wanted a lot of velocity for a very broad power curve. Your not going to get that with a Max Wedge size intake runner, in this small of an engine at the RPM its going to run. It will be a bit doggy below 4000rpm. Not what I or my customer wanted. So we took the Victor enlarged and ported the runners right up-to the main plenum area. Not a lot just a little. More so on the width than height. The "eyebrows" were left as is.
 The other reason I wanted to use the Victor is because of the smaller intake runners vs the Max Wedge runners in the head. The runners "step down" into the head. This creates a lip heading back up into the intake. What this does is helps keep reversion pulses away from the carb and intake plenum area. It really helps the engine run much more efficiently as seen in the BSFC. The heads were milled a lot to get the compression where it needed to be and that pushed the intake up on the heads. Normally we would mill the intake face to compensate for this, but in this case it was a desired effect. Now the top of the runners match up better and the larger step is at the bottom of the port. This is not as critical an area as the top of the port. As you can see from the arrows, the port width is very close, but the intake port is smaller than the port on the head.
The intake has a pad for a standard square bore carb but we wanted to run a Dominator. So a 2" adapter was used. It was bolted in place and plenum matched.
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