85 305 heads?

[FMXhellraiser]

Well I looked more at the truck today, found out it's a 85 not 84. It has a 5.0 liter in it (305) and I am going to be fixing it up and putting my own money in it along with my dad putting his money into it to (first and only father son project) and we are thinking about putting better breathing heads on this thing without having to modify ANYTHING, just a plain bolt on. I understand I can use 350 heads on this.
Now here is the plan. My dad thought about the 305 and how it has 135,000 miles on it and said he wants to build a nice streetable 350 for it next when the 305 goes (which we are hoping that wont happen for quite some time now). So if I get a Edelbrock carb, manifold, etc I can just switch it right over. I would like to get heads for this but not spend heaps of money on them and be able to switch them over too.
Any reccomendations (sp?) here?
I am not sure about the 350, I think it would be cheaper to just rebuild the 305 IMO but my dad paid for the truck and I am helping buy parts and being able to drive it so it's up to him really.

I appreciate any info given here.

[Matt167]

The 305 heads are your only real choice for the 305, unless you put in flat top pistions, there 58 cc chambers and yield a 9.5 to 1 comp ratio on a stock 305, ising 64 cc heads would be acceptable but lower the compression to 8 to 1 ( approx ), 76 cc heads would be horrible. just do some head work to the 305 heads, it is the best option you have, other than getting some 49 cc heads to bump the comp ratio to somewhere around 10 to 1.

[FMXhellraiser]

Hmm. Well compression ratio on this stock one I think a 8:1 compression I read somewhere. In 87 I think is when they bumped the 305's to 9:1. So I really have no other choice? No aftermarket fully assembled heads for 305's that will do good? I can do the piston thing when I rebuild and should wait for the heads then. If that is the case then what compression ratio is good if I want more power but keep it a streetable motor? I will start with that question since I can't really ask about the pistons yet without know what cam and everything else to run.
All I know is that this 305 is VERY sluggish and has absolutely NO power right now. Of course putting on headers, exhaust and air filter and carb will help but still isn't going to be much more. I want this thing to run better and quicker than my 302. That would be nice I think.

[Matt167]

I think all 305's are 9.5 to 1 with the 58cc chambers, as all 305 heads are. a set of 49cc chambered heads would bump to 10 to 1, give ya more power, you could get away with 89 octane saftly. if really have an 8:1 motor, than the 64cc heads would give you approx 7:1, in affect decreasing power. the 49cc heads seem to be your only liable option other than stock reworked, without a full rebuild

[FMXhellraiser]

Ok I see. Thanks for the info Matt. I think maybe I should wait till rebuild and just put a better cam in for now huh?