Head recommendations for an SBC 406

[maverick2]

I'm in the acquisition phase of my 406 buildup. Goal is 475-500 ft-lbs peaking at about 4400 rpm, running smooth and strong from idle up thru that rpm range, and topping out at 5000 rpm. I've narrowed my choices on heads to Canfield 195's, or the Brodix IK 200's (I've got great price options on both, so dropped AFR from the mix.) Any recommendations? Pros/cons of each based on experience? Thanks.

[jt1]

I've had the Canfield 195's on my 355 for about 3 years now. I've been pleased with them and would buy them again, they offer good hp/$. I bought bare heads, cleaned up the bowls myself, built them with Ferrea valves and Comp hardware. They did everything Canfield advertises on a local bench that is considered a little tight. The engine makes decent power and I've had no problems with the heads, so I've been pleased.

 

John

[Jerminator96]

200cc intake runners seems a bit small to me for a motor that size, but then I've never built one that topped out at 5000rpm either, so you're probably fine.

 

What is a "good deal," and is it so good you wouldn't consider a set of Dart Pro1s?

[310z]

I have run Dart Iron Eagle heads 180 cc runners on a 388 The bowl and intake were heavly reworked for a heavy boat that runs up to 5500. They work great and heve for years now. The engine builder usually used 220 cc intake runners for race engines turning 7000. I called Dart and asked them what they recomended for the purpose I needed and Dart recomended the 180 cc. Dart was right, they work great for the low rpm I use them at. But if I was building a 406 to go in a light Z car, I would go with aluminum heads to save weight and they can disapate heat better than cast iron, 220 or larger intake runner with at least 2.02 intake valves all roller please. Place a cam that will provide max hp at 5500 to 5800 rpm. Something like 280/280 on a 106 LCA. The toqure will come on a little later in the rpm range and save some rubber on your tires. There is a great easy to read book with dyno charts called How to Build Max Performance Chevy Small Blocks on a Budget by David Vizard.

[maverick2]

What is a "good deal," and is it so good you wouldn't consider a set of Dart Pro1s?

The "good deal" on the Brodix IK 200 is $825 (heads are complete), while the Canfields were about $250 higher. Was originally leaning toward the Canfields, but at that price for the Brodix, they are kind of hard to pass up... As for Dart, my builder had problems with the last 3 sets of heads he got in from them, so he's not a Dart fan right now.

[maverick2]

Place a cam that will provide max hp at 5500 to 5800 rpm. Something like 280/280 on a 106 LCA. The toqure will come on a little later in the rpm range and save some rubber on your tires. There is a great easy to read book with dyno charts called How to Build Max Performance Chevy Small Blocks on a Budget by David Vizard.

This 406 will be going into an aluminum jet boat. Pump/impellors will be set up such that torque demand gets too high to turn past 5000 rpm. On plane at 2800 rpm, cruise at 3200 rpm, and play between 3200 and 4800 rpm.

[310z]

Now that I know that you are talking about a boat things are different. You need smaller intake runners for the low rpm. I80 cc like I have would work great. There is a much bigger issue here because this is going in a boat. The type of cooling system to be used needs to be considered. If you are using lake water you can not use aluminum heads. Electrolisis will eat them up and cause hot spots in the chambers, pre detonation ultmatly distroying the heads. The dirtier the water you run the faster it will happen. If you are running in Lake Tahoe you would probally be ok but anywhere else and the motor will distroy it's self. So the options are cast iron or get a closed cooling system. After I built the motor in my boat using the iron eagles I found out about the closed cooling system. Then I could have used the aluminum heads. The cooling system was one of the best devices I put on my boat. The block has anti-freez in it like a car. Winterizing has become a minor chore and the motor runs a constant temp.

But there is more. Cam choice is criticle in a boat. If you are running water injected headers, water can get sucked back into the cylender through the exaust valve if the cam loab center angle is to large thus hydr-locking the motor. Information about boats is hearder to come by but its out there, check some hot boat sites. The more research you do the more money you will save in the long run and enjoy the boat for a longer time.

I have an old classic Century Resorter, direct drive with the 388. It is a total sleeper. It pulls a skiier out of the water better than all the new competion ski boats and has a top end of 50 mph on gps at a 5000 ft elevation.

My friend that I boat with has a old classic V-drive drag boat with a blown 440 which he built. Both our boats run flawlessly. You dont want to have trouble on the water. It's hard to walk for help.

I am no expert on boat motors but I have a little experence with them. Of course you know that for low end toqure nothing beats a big block.

[maverick2]

I'll be running a closed cooling system with wet exhaust. Exhaust manifolds are performance manifolds with high center risers so water reversion back into the exhaust is less of a problem. Planning on using a marine cam to further inhibit reversion and tailor the torque curve to the application.

 

Now back to the heads... Brodix IK 200's vs Canfield 195's???

[310z]

I think I would go with the Brodix. They have a good reputation, there is only 5cc difference and you have plenty of cubic inches under those heads to keep the intake volume moving at a good speed for proper mixture. The best part is you will save $250.

[Jerminator96]

There is a great easy to read book with dyno charts called How to Build Max Performance Chevy Small Blocks on a Budget by David Vizard.

 

David Vizard is my hero. A lot of the stuff I may say about performance that sounds intelligent is probably stolen from one of his books or his website forum.

 

The "good deal" on the Brodix IK 200 is $825 (heads are complete), while the Canfields were about $250 higher. Was originally leaning toward the Canfields, but at that price for the Brodix, they are kind of hard to pass up... As for Dart, my builder had problems with the last 3 sets of heads he got in from them, so he's not a Dart fan right now.

 

That's a hard deal to pass up for new, complete heads. And you never want to make your builder mad so you should probably stay away from the Dart stuff.

 

My vote is Brodix. They're as good as you need them to be and they are fairly cheap.

[Pyro]

I would use small ports, like vortec heads. Chevyhiperformance.com built a 406 with vortec heads and made like 530 ftlbs and 470hp with a moderately sized hydo flat tappet cam. The cam was around 230 degrees at 0.050" but the small ports made huge torque and fairly good hp. ran on 87 octane too. I think it had 400ftlb of torque at 2000 rpm. do a search on that site.

[Pyro]

here you go

 

 

http://www.chevyhiperformance.com/techarticles/148_0401_chevrolet_406_ci_engine_build/index.html

 

http://www.chevyhiperformance.com/techarticles/148_0306_chevrolet_406_big_block_torque/index.html

[dr_hunt]

I would use small ports, like vortec heads. Chevyhiperformance.com built a 406 with vortec heads and made like 530 ftlbs and 470hp with a moderately sized hydo flat tappet cam. The cam was around 230 degrees at 0.050" but the small ports made huge torque and fairly good hp. ran on 87 octane too. I think it had 400ftlb of torque at 2000 rpm. do a search on that site.

 

That was with the AFR 180 heads, it made about 62 less hp with the vortech heads so around 408hp. The brodix heads would make more power in a similar curve to the AFR's so the tq and hp would probably move up in the powerband somewhat. The ideal combination would be to run alittle more compression, alittle tighter LSA and get the peak torque in the right spot early on in the rpm range IMO rather than the 110LSA used in that test.

 

There was another thread on this same subject earlier but the author was wanting to go 383.