304 Engine 360 heads

Can you put the 360 heads into a 304 motor and is there any complications with that? Do they fit perfectly

 

from what I understand the 304 has smaller valves, and the 360 and larger heads will not function properly on a 304, but the 304 heads could operate properly on a 360.

Timgr will probably know better, but I'm gonna say no.

 

No it won't work. Something about valves.

 

Why not just go with the whole 360?

 

Ok, that is what I thougth.. even though some have said that it works and gives it more horsepower..

 

You'd need to make some small fly cut reliefs at top edge of cylinder walls to clear the valve(s). Not sure if both interfere or just the intake. But it can be done. Even though the valve will clear, it will be shrouded by close proximity of cylinder walls. HP will increase at top end for sure with bigger valves. How high do you want to rev your Jeep? Also, smaller valves give better fuel-air mixing due to higher charge velocity. Big ports and big valves cause sluggish fuel-air charge mixing at low RPM, which is where most of us run. That racey stuff only works at higher RPM. Now, on a larger displacement engine the mixing is still decent because it's pulling more volume per intake event so the velocity is still decent. I don't know if 360 heads on 304 WILL cause poor idle, but I know for sure that slow fuel-air velocities at low RPM can cause idle problems and the 360 heads on a 304 will lower your velocity.

 

Well I could do that. this guy was selling rebuilt pair of 360 heads for 50 $ that is why I was thinking about it

This other guy is selling a 360 motor for $300 and another guy is selling a 304 for $200.. so will see. I think my heads need rebuilding so that is why I was thinking of the $50 dollar 360 heads...

 

I don't know what your budget is like, but if your Jeep is set up for the 304, and you are likeing how it is, a quality rebuild of your existing engine would be a better bet than swapping heads, or swapping engines with an untested 360.
But that is just what I would do, YMMV.

 

Well my motor works well. but I do hear a tapping on the heads... so I saw these heads and I thought maybe I can do this .. but I guess its better to rebuild the heads that I have if they need work..

 

Unless you know the history of the heads or know the seller real well I'd question if the heads are really rebuilt or not for $50. You may be creating more headaches for yourself by jumping into them. One of the biggest advantages of the 360 heads other than larger valves is the smaller combustion chamber most have. This will bump up your compression some which may or may not be a good thing. If the 360 heads are real early versions they will have stud mounted rockers. If the later version then they will be bolt/stand mounted rockers. If you have tapping from your heads I'd pull the valve covers and look for worn rockers/stands. The stands IIRC are aluminum and a common wear point.

 

How much to rebuild the heads ?? any ideas ??

 

Their getting $300 in N.E

 

Remember also that not all 360 heads were created equal. The 334 heads are less desirable, the 502 casting heads are the one's everyone looks for.

High5

 

Come up to the gold country and take my 360 away!

 

Info so far about the 360 valves interfering with the 304 bores, that's right. You could make the 360 heads fit with some machining, but IMO it's not economical considering the cost of swapping a complete 360 instead of just the heads. A 360 is basically a 304 with larger bores and valves, so swapping a complete engine is as easy as can be.

I'd advise that you not start swapping parts around to fix some non-specific noise. Are you sure it's coming from the valve train? Broken rocker bridges are common on these engines (DanStew had this problem with his Commando IIRC). Worn bridges could also be the cause, or a collapsed lifter.

There are other causes of noises too ... worn fuel pump, exhaust leak, etc etc.

Man, I'd suggest you be systematic when approaching engine problems like this. Swapping or rebuilding the heads to maybe fix a problem you know so little about seems like exactly the wrong approach. Do you know your oil pressure and compression? Hot idle OP is critical for these engines. If your engine has good OP and compression, I'd suggest you consider it a solid base to start from, and focus on diagnosing your noises.