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305 block

661 views 8 replies 3 participants last post by  **DONOTDELETE** 
G
#1 ·
It seems that I have aquired a 305 block and heads...all stock.
Any suggestions on what I might beable to do with this?
I still have my old S10 Blazer, and was thinking that it would make a good home for a V8.

So just looking to see what some people might suggest for it.

not that I have the money for it, but I tend to aquire such things, and over time make something of it.
 
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#3 ·
What is the motor out of? If it's a high compression one then it's got the 58cc heads and there are a lot of potential in them.

A wisely chosen cam, headers, intake, and tuned carburetor can get some serious ponies out of the motor.
 
#7 ·
I found one of my old posts. Since you've already got the 9.2:1 block then some doesn't apply. I got some of the stuff out of an old (circa 1985) Hod Rod magazine.

I've been researching this lately. I actually plan on rebuilding my old 305 and putting it in place of my 350. Then I'll rebuild my 350 and put it back in place of the 305. It's a good thing motor swaps only take 6 or 7 hours.

Anyway here's what I'd do and the order I'd do them. #5 has two parts because you can choose one or the other.

1. Tune your carburetor. Get some DR rods for the secondaries.
2. Edelbrock 2101 intake. Good for ten horses or so unless you've got a crappy equalized dual plane intake then it's worth more.
3. Headers. Good for just about ten horses. Find 1.5" primaries if you can because otherwise you'll sacrifice some low end torque.
4. 2" open spacer under the carburetor. This slowly generates horsepower but it doesn't break the 5hp mark until 3500 rpm. If you've got room, stick it in there. It's only $20. Worst case scenario is that you'll lose some bottom end torque and you'll have a $20 piece of phenolic plastic that would go great on that 400SBC powered Camaro you've been dreaming about.
5a. Find some 58cc heads if you don't already have them. Get them machined for 1.94 intake valves instead of stock 1.84. If you can, find a set that you can mill some material off so you can get the compression up a little higher yet.
5b. Camshaft. It seems that 108° works the best. I don't know anything more than that--I'm still researching.
6. Rebuild. Stick some higher compression pistons in it. Port the heads.

After both #5s and a rebuild you're supposed to be able to squeak 250hp@5,000rpm with a properly tuned carburetor.

Most 305s had between 7.5:1 and 8.0:1 compression ratios. If you take that up to 9.5:1 you'll see around a 5% horsepower increase. You figure 2-3% per point of compression increase.
 
G
#8 ·
If the bottom end was deccent I would say get a intake and headers and such and run the piss outa it till you can save up and swap them to a 350. If it has spun a bearing I would save up for a 350 to rebuild. The small cc chambers are nice though, you can get some good compression outa them like has beed said. My advice is save for a 350 and spend your money one that.
 
G
#9 ·
uhh I think you missed the point. I have it, why not rebuild it. I have a s10 blazer i can put it in *shrug*.
If I come across a 350 prolly build up that too but, well my K10 already has a 350 that's 30 over.
It's not a question of which is better, just what I got and what I can do with it.
 
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