Did anyone ever go crazy on the 305 TPI heads ? Full port & polish, etc.
My 305 with the factory 350 cam runs real nice from the factory since day 1. Bottom end is amazing. Torque monster.

I know the 305 heads have small chambers. I bet it could be woken up even more without going to the 350, or LS. Just stock bottom end 305.

 

The valve shrouding and small diameters could be a restriction. By the time the chambers were opened enough to provide decent perimeter clearance, some of the compression advantage of the smaller chambers would be lost. There are not many "easy" alternates for the 305, given the smaller bore. World Products used to offer somewhat improved 58cc heads for the 305, but were not widely used,

 

In years past people would get bored with their ZZZ-ZZ4 crate engines. They used the 113 aluminum 58cc Corvette L98 heads. The later model ZZ4s had a little higher flow and better springs than the earlier years. They make an excellent head for a 305 especially with some porting. Probably the best head for the $$ to use on a 305 would be the 113s, and have Lloyd Elliot port them. Best way to ship cylinder heads is to sandwhich a head gasket between them, bolt them together, the wrap them both in a heavy layer of packing so that they are well protected in the box.

 

Would the 113 heads ... the valves clear the cylinder walls ?

 

Yes, I just wrapped up my fifteenth set. Just know how much you can get away with, no need to go overboard or you'll hit water. Also, for a 305, no need to go with a 1,94" valve from the 113 head, it's more important to focus on bowl finessing of the 1.84" valve, and a larger exhaust valve if you have the means. I always run them at 1.84"/1.60".

- Rob

 

Yes they clear. Only a 1.94 valve.

I have found the 1.94/1.60 valve combination to run best on a 305. Notch the 305s bore like a 366/396/402 big block and a 2.00" valve can also be used. My buddy David Kauffung ran ported Fast Burns on his 305.

 

I always run them at 1.94/1.60. Just not enough valve curtain area at 1.84 and you hit a wall with flow. The 059 Vortec 305 heads jumped nearly 15 cfm going from a 1.84 to a 1.94 with a little bowl blending for the larger valve.

 

Highly depends on who is doing the work to the cylinder head. I myself would never even consider running a 1.94 intake valve unless the starting point of the bore were 3.875" from say a 283/307...

- Rob

 

Alot of the big names don't even port cast iron heads any more....

 

You can't let that stop you, ask yourself how bad you want it done... then get it done. Remember, you can calculate supported horsepower using a cylinder heads cfm flow, but then ask yourself what your engine is capable of making, not someone elses. Sure, there are heads that can flow close to 250-cfm right out of the gate, but 250-cfm supports close to 390-400 horsepower. So if you're not making that much, or plan to make that much with your 305 naturally aspirated, then what would it matter if one head flows this and the other head flows that on the bench. You said yourself your engine pulls good for what it is, and you'd like to enhance on that, or improve on it. Yes, companies like Brzezinski stopped working on open chamber heads, but that doesn't mean it can't be done. Companies also stopped tuning OBD1, but we're still here doing it. If you're curious, here is my most recent set, upper and lower sides of the ports. Still have to finalize polishing, and the guides have been taken all the way down in the bowls, but you get the gist. These are going on a stroked 305 to 334, and they will do just fine. You don't need Vortecs...

- Rob

 

Are you really in Rock Hill? I grew up there, and Woodridge. I still go back to enjoy the memories......
How many hours do you have into a set? start to finish ?