zed-028

Before i begin

Point 1 - I like my 305
Point 2 - 350's are not in huge supply in Australia (not are any chev parts really)
Point 3 - If you fancy saying "just get a 350" take your opinions elsewhere

So with that out of the way, i was going through looking for some half decent heads to use with an 87 LG4 (not a roller cam engine, suprising i know but hey, its 87 - anything goes)

The usual issues with using heads off of the 350 on a 305 is the resultant compression loss, ludicrously large combustion chambers etc. I was initially looking at some trick flows or some world products heads for the 305 when i came across these

https://speedmaster79.com/engines-co...st-iron-heads/

They share many of the same specs with the Trickflows intake and exhaust runners but with a 3cc combustion chamber increase. 3cc is pretty minimal compared to the usual 64cc and up combustion chamber sizes.

They're obviously still aimed at 350's due to the larger valve sizes but assuming that you kept the lift of your cam to something less than about .450 i get the feeling that these might actually produce some decent power.

Any thoughts?

*seriously, anyone saying "get a 350" or similar will be mailed a dog-turd

Orr89RocZ

iTrader: (20)

You could shave them down even more. With iron heads you dont need as much compression in a sense compared to aluminum since iron holds heat better. But they seem decent. 1.94 valve should have plenty of clearance in that bore so you can run as much lift as you need, which wont be much. 305 typically wont need much. Even a 383 can make 530 hp with something like .550", so a 305 in the .500" range would be great. Just make sure the heads are set up for the cam you end up running

Jorlain

iTrader: (4)

What heads do you have now?

Were I in your shoes, I'd simply port and machine the 305 heads, unless they're already junk. Bring it in to the machine shop, have them hog it out for bigger valves. Bring it home, port it, bring it back and have them do the valve job.

Look up books by David Vizard on SBC cylinder head porting.

Additionally, here's a thread with some porting info about 601\081\416 heads.

https://www.thirdgen.org/forums/tech...-pictures.html

zed-028

Yeah i've already looked at getting my stockies ported - We have this thing that we call the Australia Tax where we pay 6 million times more for everything than the rest of the world because we don't really make anything here anymore - and in Western Australia people are super greedy.

to give you an example of this, getting a cylinder bored 30 thou over is about $180... each.

Machine work on heads is also stupidly expensive here (bit of a rarity to find someone who will actually do it in the first place) hence why im looking elsewhere

Jorlain

iTrader: (4)

Understood!

That's a shame. To be honest, I'm both surprised and disappointed at the same time. I guess I just sort of assumed that there were a lot of craftsmen there, with some of the great goodies the US was importing from Australia at one time.

Well, that said, best of luck to you, sir.

DynoDave43

iTrader: (11)

It would be nice if there was some feedback on their site about them.

I'm going to guess that these are new castings, and further guess that at that price, fully dressed, that they are Chinese castings. I've read a lot of negative stories about heads from China. Dimensions out of spec, poor machining etc. I'm not saying that I know these suffer from any of that, but again, some feedback from previous users would be helpful.

zed-028

Yeah our last 2 Car manufacturers pretty much shut down recently, Ford Australia and Holden (GM)

Saved some of their best stuff until last. Up until recently Aussies have always had a love affair with 4 Door RWD vehicles with overpowered V8 engines. In their final death rattle Ford released a 4 door 470kw Supercharged V8 falcon GT and Holden released a 4 Door Commodore powered by an LS3 (pinched from the corvette).

Now they'll be selling european stuff thats either FWD or AWD with economy and green stuff in mind. eww

GeneralDisorder

iTrader: (1)

What about some 305 Vortec heads?

GD

NoEmissions84TA

iTrader: (1)

Those Speedmaster heads look to be just what you need.

You should also look at what Ja85z28 did:

https://www.thirdgen.org/forums/tech...-aerohead.html

https://www.thirdgen.org/forums/auto...onversion.html

lltrevino

iTrader: (1)

383

lltrevino

iTrader: (1)

zed-028

lol - good call