350 with 305 heads ????

I have a motor I picked up for a streetrod project.

In checking the numbers it is an 1985 350 cu" truck block, but it has heads with casting # 14014416 which are 80-86 305 cu" with 1.84" intakes. Not sure of the head cc's.


Can anyone give me the low down on these heads and how they may or may not work on the 350 block.

I'm running a 260/268 adv dur. cam with 114 lobe separation

 

What I found is there were used on 267 305 and 350s. We used them on low buck dirt track engines, they have a small combustion chamber, that raises compression. They have small intake and exhaust runners. They'll work on a 350.

 

Those heads will work real good on a 283 . In fact they work better on a 283 than the double hump 300 horse heads. OldWolf

 

Yeah those are 54cc chambers and I belive a 150cc runners really not bad heads on a small motor or mild motor. I had some on a decked 355 and a cam to make up for the heads that pushed a 4500 lbs car to mid 13's on motor but mine were ported so had just a small valve size and chamber and a 195cc runner.I say run 'em they are great dirt track heads.

 

Run em !

 

I'm pretty sure the 305 heads were very small combustion chambers, and might be too much compression for "pump" gas if the 350's got flat-top pistons.

 

throw those crack-prone peices of shit in the garbage and buy a set of Darts. then, You will make REAL power. not mullet-Camaro dirt modified disposable engine power.

*for the record. a 350 with 305 heads is still my favorite engine to make fun of. I was raised in a crap town that this combination was the standard issue dipshit hotrod motor. Every one of them claimed 400 horsepower, yet I still managed to outrun them with a 330 olds.

blech.

 

Damn Arlo, tell us how you really feel.

 

I'm just getting warmed up.

 

I have a 350 with 305 heads in my dodge pickup, and it is limited by the valve size, but I can run it on premium gas with no knocking issues. It is great for low end power, but it falls off up in the revs. it works great for the around town driving that I do in my toy cars. I would guess I am making a bit over 300HP, but it is definately slower than my ZZ4 at 355 HP.

 

I use the larger chambered version on my 350. They are something like 67 CC's. I ported them and had 194 intakes installed. The work great with flat topped pistons, and an RV cam. The smaller chambered version really shroud the intake valves even with the stock 184's. But they will jack up the compression for you cheaply.

 

The 416's are one of two 305 HO castings, The other I believe is '601. The intake side flows very similar to the old '461 327/300 HP heads when cut for 1.94 intakes. Exhaust side is a little weaker but close. A split duration cam with 1.6 rockers on the exhaust side helps. By the time you open them up for 1.94's and unshroud the intake they will be more like 64cc instead of the advertised 58cc and you have to be real careful when you starting grinding on the bowl to unshroud them because you're getting close to the water jacket. IF they aren't cracked, and that's a big IF, as mentioned earlier they are great heads for a 305 or 283, they'll "work" on a larger engine.

If it's just a daily driver they'll make great low end torque and help fuel economy with your cam choice if you can get the compression down. The '85 pistons are going to have about a 12cc dish IIRC with the piston .025 down the hole and a standard .041 head gasket that's going to put you in the high 9's for compression and Dynamic Compression with that short cam is going to have you screaming for some real high Octane. Can't access the KB compression calculator right now. I was going to throw together a 350 from leftover's for an old truck and I've crunched the numbers before trying to come up with a piston and cam I could use to run those heads with and still run 87 Octane . With a short cam like that you need a 22cc dish to keep compression down where you can run 87 Octane and that's marginal. Sealed Power has a set of cast pistons made just for this combo but they are a full dish not reverse domes so you lose out on the quench effect.

Bottomline, by the time you jack around trying to make this work on readily available fuel you could have gone out and bought the right heads ready to go. Sell 'em on Ebay and find a good set of L98 Vette aluminum heads. Better flow, light weight and even with the higher compression you can run 87 Octane. You'll be money ahead.

 

416 casting number heads were on the High out put 305's in monte ss and camaros.

It's a 58cc chamber and not a 54 cc chamber.

I would think it would constrict a 350 somewhat.

A 1.94 is a good head for a 350, 2.02's are good if you are in high RPM's alot.

 

When I use the 305 heads on a 350 I would cut them for 1.94 valves, and unshroud the combustion chambers. You do this and you will end up with around 64cc.

If you don't you WILL have a ping, and you will rev to 4500rpm and hit a brick wall. They just don't quite flow enough stock.
Jeff

 

another 305 HO head is the 081 casting
these were on the later TPI motors.