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Author Topic:   ? about chevy 307
Dirt Maniac

Total posts: 169
posted February 14, 2005 08:22 AM  
Exactly what are they.
I was under the impression they were a 4.00 bore with something similar to a 283 crank,but not for sure.

Back in the early 90's dad got a 307 and ran it in his pro stock for a few races to finish the year,and used it in a few play days.

We had talk about using this motor for a few playdays in my mod,putting some double hump heads on it and go.

Are these motors any good for anything.


Dirt Forum Champ
Total posts: 715
posted February 14, 2005 08:48 AM  
Go to the toolbox on this site.There is a breakdown of engines and lots of fun stuff.

Dirt Maniac

Total posts: 138
posted February 14, 2005 09:43 AM  
I run one in my pure stock and I see quite a few people run them in the wissota midwest mod class too. They are a 3.875 bore (stock bore) and 3.250 stroke, same as the 327. I run mine against mostly 305's and it seems to do pretty well. Last year I was running the stock 185 casting heads but this year I'll be using some 416's to bump the compression and get better flow.

Dirt Maniac

Total posts: 192
posted February 14, 2005 11:42 AM  
we ran 307 .060 over motors in our NJ DIRT modified where there was a cubic inch limit They made some great power.

Smaller bore then a 350

Dirt Forum Champ
Total posts: 5390
posted February 14, 2005 05:24 PM  
If you're running in a class that won't allow a 4" bore (327, 350 etc) the 307 block is the best to build from. The bore is about .125 bigger than the 305 block and unshouds the valves better. 1.94" and 1.6" valves are pointless in a 305 but would work great in a 307.

Dirt Maniac

Total posts: 169
posted February 16, 2005 07:58 AM  
Thanks guys,Dad swears by the little motor,never been apart after he did some work to it.

I was thinking taking it out for practice in the mod,since my good motor wont be ready in time,and then keeping it in the corner for a back up.The track I race it is kinda sandy,so it goes from sloppy to dry pretty quick.

Thanks a bunch

Dirt Roller

Total posts: 14
posted February 17, 2005 02:18 AM  
Like any motor - in general terms, displacement equals horsepower.
If nothing else, c.i. is the simplist, cheapest and fastest route to pure power.
To make a 307 produce the same power as a junk yard 406, would cost a huge amount.
Winning races however is as much about power delivery as it is total power, and that is where a 307 can shine.

Dirt Newbie

Total posts: 1
posted February 17, 2005 06:50 PM  
Speaking of the chevy 307, Has anyone ever tried building a stroker out of it by using a 400 crank? I know pistons would be a problem to find. Anyway does anyone think this would be worth it? I'm guessing it would be somewhere around 360 ci depending on bore size...Just a thought.....

[This message has been edited by hobby72 (edited February 17, 2005).]

Dirt Forum Racer

Total posts: 80
posted February 18, 2005 06:52 PM  
Copied this from Who-Won classifieds, just to show how this one was put together.........Submitted 2/18/2005
Price Reduced...MUST GO!

I have a nice 307 stroker motor for sale. Great for B-Mod or Hobby Stock.

-3 3/4 inch stroke SCAT crank inside 307 block with 350 block numbers. (internally balanced)

-Lightweight 4340 Eagle rods.

-JE Ultralight Pistons with TotaL Seal Rings.

-This small block cubes to 360 cubic inches, 9 to 1 compression. A killer in the torque department with tons of HP. Selling as a shortblock.

John Smith
Des Moines, Iowa 50303
Home Phone: 515-555-5555

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