82Five-O

Which heads would be beter 461 camelhumps or 58cc 416 heads?

tony_cogliandro

iTrader: (3)

the 416's are 58 cc's and the 614 is 64 cc and right for a 350.
if you put on the 416's you will get about 11:1 compression and probably they will not flow right. you will also have to make sure your valves dont hit the piston tops they have a smaller cylinder size. there are all kinds of problems and you have to be prepared for it.

you need to talk with attila the fun, or kevin91z, or his dad dyno don, or maybe big gear head - they are all really up on this topic, and a lot more too.

Air_Adam

305 heads will work fine on a 350 - no more chance of anything hitting the pistons than with any 350 head or any other head for that matter. They will also flow just fine with the bigger bore of the 350 - infact, maybe even better with the larger bore size of the 350.

I used a set of 305 heads (601 to be specific) on my 350 and they were great, they worked very well. Compression was high, around 11:1 since I had flat top pistons, but I had a pretty big cam too, so that and a good tune and it ran fine. Would work better with dished pistons, but most 350s have dished pistons anyway.

I would go for the 416 also, because the 461 would not have any mounting holes for your alternator and power steering pump. The 416 does.

tony_cogliandro

iTrader: (3)

im doing the same thing - but he has to know that there may be problems and he needs to plan for them.
he needs 350 gaskets for his 305 heads.
and yes you can hit the pistons so you have to make sure you are not using domed pistons.
you also have to pay attention to compression ratio's when you used 305 heads.
as a matter of some caution you should probably get a new valve job, hardened guides, maybe pin the studs, and then you do need to get higher compression springs and cut the seats down a little, or go with .05 negative on the bottom and top and use the 10 degree locking caps [i know that is not the right word for it] for a little more strength.
not having proper heads is like running a race with your nose blocked off. you can run but you will never run at your potential.
and sorry for not listing you too - air-adam - you are right up there on the knowledge scale.
its not that using the 305's is wrong, you just need to be prepared for any possible problems.

Air_Adam

I assumed he was not going to use domed pistons because no one really does on street engines anymore, aside from the BBC crowd because they actually do need them. And plus, if either of those heads are unmodified castings, he'll run into problems with the valve guides/springs/etc causing problems with too much lift before he will ever have valves slamming into pistons.

All that buildup of the heads for extra stregth - depends what cam he's going to use. If he's using a fairly tame aftermarket cam or a stock cam, then most of that work is probably not necessary (not a bad idea, just not req'd at this point)... but if he is using a more radical cam and/or heavy springs, then it might be a good idea. I'd recommend having the heads machined and tapped for screw-in studs instead of pinning them, if you know ahead of time you'll be using a fairly aggressing cam. Its a better way to do it IMO.

The 350 head gasket was a given - I figured anyone who could take on a job like this, and knowing something about the two castings he's deciding between, would probably know this, so I didn't mention it.

82Five-O

i have the camelhumps on the motor now, i have a comp 12-238-2 cam, i love it and am not going to change it. Iwas just wondering if switching to 416 58cc 305 heads was a good idea to make more power than the camelhumps. I believe i will make the switch to 416 heads and raise my comp. ratio slightly to make more power. Thanks for ur input.

Air_Adam

I doubt it would make any really noticeable difference in power, assuming both are in good shape and the engine is tuned properly. They are very similar to each other.

82Five-O

yea except the 416 are 58cc heads. That would raise my comp. ratio and more compression means more power generally right?

Stekman

Generally speaking yes. The more mild the engine is now, the more of a change you'll see. Rough estimate - you'll see 3-5% increase.

Air_Adam

You will see an increase, but not much. Its usually 3-7% for every full point of compression.