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Author Topic:   307 SBC?
rollingviolation
Dirt Roller

Total posts: 18
posted May 15, 2005 08:50 PM  
Argh. I grenaded the 350 in my Camaro today. Something (not sure what yet) caused the oil pressure to start dropping and eventually it blew - I have the holes in the oil pan to prove it. Next race is two weeks away... I can probably get a 307 that was apparently from a 71 Chevelle. Are 307's Good? Junk? I don't want to go out and waste my time if it's going to be gutless/self-destructing... I've gone through two engines in 6 races... I'm thinking I should just save up for a quality rebuilt shortblock.

Oh... and they do go BANG when they blow. Sounds just like in the video game.

The lousy part is the car was PERFECT otherwise. <sigh>

jay116
Dirt Freak

Total posts: 428
posted May 16, 2005 06:29 AM  
If you can get the 307 for $25-$35 to get ya going and then save cash.I twisted a 305 for a while nothing like my 383 though.

Busch
Dirt Full Roller

Total posts: 46
posted May 17, 2005 04:58 PM  
if the track is good and slick it may be just what the doctor ordered. A buddy of mine had the same thing happen a few years ago and won a championship out of a stock 307. Good luck!

racer17j
Dirt Forum Champ
Total posts: 5390
posted May 17, 2005 06:57 PM  
ok, if I go with the 307, should I swap heads?
I have a pair of 882's and a set of 624's. Both have 1.94 intakes.

What about my 450 lift cam? Assuming it's not wasted, is that too much cam for a 307?
(2bbl 500cfm rochester... stock manifolds.)


rollingviolation
Dirt Roller

Total posts: 18
posted May 17, 2005 07:30 PM  
I've also got a set of 305 heads... would they give me higher compression? I can't go past 9.5:1... and stock is 8:5 or so for the 307 - don't know the casting #'s yet... all we know is it spins over and is in a friend's yard - think it's from a 72 Chevelle.

305 heads? 882? 624?

51racing
Dirt Maniac

Total posts: 138
posted May 18, 2005 09:44 AM  
I run a 307 and I'm very happy with it's performance. I have 305 heads on it, stock manifolds and cast iron intake with a .465 lift cam, so I wouldn't say .450 would be too much, but you may be pushing your 9.5:1 limit with the 305 heads if you're running flat tops, at the very least, run thick gaskets and you should be really close to that limit. You'll probably want a cam that works in the higher ranges as these things like to rev, I've turned mine 6500 and it's still pulling pretty hard with mostly stock parts.


racer17j
Dirt Forum Champ
Total posts: 5390
posted May 18, 2005 09:57 PM  
The stock 307 heads don't flow that well stock(1.72 intake valves). If you run 305 heads for compression, they flow a little better than the stock 307 heads. I suggest the 416 or the 434 casting 305 heads, they flow better than the 601 heads, and you will probably be safe on the 9.5 to 1 compression rule because the 416 heads on a flat top 305 is 9.5 to 1 with a steel head gasket. Go with a good composite head gasket for the 307 (Fel-Pro) and you should have no problems.

rollingviolation
Dirt Roller

Total posts: 18
posted May 19, 2005 07:02 AM  
Thanks for the suggestions guys.
We'll be pulling the blown up 350 on Monday and figuring out which engine to fix up.

What about taking the 307 crank and putting it in the 350 and making a 327? I'd have to get the whole thing rebalanced, wouldn't I?

ruggs66
Dirt Maniac

Total posts: 193
posted May 22, 2005 09:50 AM  
Yes.

racer17j
Dirt Forum Champ
Total posts: 5390
posted May 22, 2005 12:18 PM  
running a 307 is better than not running at all. I have used the 307 cranks in 350 blocks without rebalancing,ran very smooth. while you should rebalance its not really necessary with the stock stuff. get a set of speed pro pistons and go racing.the speed pro pistons are lighter than the stock stuff.and im talking about the 99 dollar pistons.

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