Picking out 454 Heads. Need help.

[Orlando87Chevy]

I have a Gen V 454 Engine that I plan on putting in my truck. But before I put it in I want to build it up alittle. I already ordered the proper head gaskets for using Gen IV heads if I have to. I want to push at 550hp if possible. What heads should I use. I have a limited budget so I might have to go with cast iron heads. Thanks for your help.

[nvrenuf]

If you're talking about using factory iron heads then the '049 & '781 castings are almost identical and work very well. These are open chamber, oval ports that were used mostly in the 70's and can comonly be found on car and pick up engines. The do have a large combustion chamber so you'll need to run a domed piston to get decent compression. They also have smaller valves which work great if you're using it under 6k but for highrer rpm's you'll want to have them upgraded to the bigger valves.

[Orlando87Chevy]

Would they work with my factory deep dish pistons?

[nvrenuf]

They will probably work because the Mark IV motors used a dish piston but compression will be around 7.8~7.9:1. That pretty low compression to get the hp numbers you're wanting unless your also adding a blower, etc.

[Orlando87Chevy]

Yeah. I search on eBay last night and found a couple of 781 and 049 set for around $500. So I'm going to look for a decent set of dome pistons then. What kind of compression will I run with dome pistons? Now if I kept my dish pistons and went aftermarket heads, what should I go with?

[Fairlane514]

You could also look for some original square port heads, look for closed chamber heads for your current pistons. The square ports may be a little lazy down low.

[Orlando87Chevy]

I did some digging and Super Chevy Magazine did an article for a 454 budget built. They used a stock bottom end with deep dish pistons and a ProComp 320CC Aluminum Heads. So I figure I would go with those.

[nvrenuf]

So what will the compression be with the dish pistons and Pro Comp heads?

How high do you intend to spin it? Those original dish pistons are cast and will not survive high rpm (~6k+).

Have you picked out a cam yet? Iirc, the Gen V short block will require a roller set up.

[Orlando87Chevy]

Im beginning to regret buying this Gen V engine. I found a couple of companies that sell a Gen IV short block with .100 dome pistons. Would that work with the 049 and 781 heads?

[nvrenuf]

Yes. I'm using a piston with a .230 dome and 781 heads (small valves) w/ .566 lift cam.

[Orlando87Chevy]

Awesome then I'm going to buy a performance short block.

[Fairlane514]

Are you just looking for compression?    Closed chamber heads may get you where you want with your current short block. 

[Orlando87Chevy]

My current block is to big of a hassle because it's the only generation nothing works on. I will just use it as a core if I need to for the short block.