Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (
-   Engine (
-   -   307 Chevy build-up (

JAKE 68 GMC 09-23-2006 08:15 PM

307 Chevy build-up
I'm getting a 70 Chevy 3/4t 4x4 parts truck soon with a possibly running 307 in it, and I was wondering whether they were worth hopping up or not. I'm thinking about putting a SBC in my truck, but wasn't sure whether to soup a 307 or just throw a souped 350 in.
I've read some pretty fascinating stories about the 307's, but also some stories that they are just plain dogs not matter what you do. I know everyone except 1 or 2 guys will say put in a 350, but I like to be different. Any input you have about building a 307 Chevy would be appreciated.

richard stewart 3rd 09-24-2006 12:43 AM

Hi Jake,
You sounds as if you want to build the 307, if this was a good engine to build don't you think a lot of people would have them instead of almost no one?
if you just want to build something different, use a Cadillac 502ci or a northstar
good luck & keep safe

302 Z28 09-24-2006 06:50 AM

If the 307 is in good shape (not in need of an overhaul) it can produce some respectable HP. However if the engine is tired and in need of an overhaul you would be better off finding a 350 to rebuild and hop up.

Contrary to popular opinion the 307 is not quite the dog people though it was. I had one in a 70 Nova that would run very solid mid 13 second quarter mile times.


larryblack 09-25-2006 03:20 PM

307's usually got single exhausts and a 2bbl carb. That is why folks said they was slugs.

FYI, the 307 was a stroker 283. It has a 283's bore and the same stroke as a 327. Remember chevy took the 283 crank and put them in 327 blocks and those engines ran right nice.

brandon624 09-26-2006 02:00 AM

I know what you mean about building something different, and I'm guessing you don't have a 502 caddy just lying around. 307s are fun to play with, but if I was hauling a load or pulling a trailor I would want at least 350 cubes under the hood. That said, 307s are cheap and fun to build because they respond well to smaller parts that most people don't want. 305 1.84 valve heads work well with their small chambers and larger ports, and are very cheap on ebay. Same for 283 powerpack heads. These heads will choke a 350 but are just right for a 307. The best setup I've had on mine so far is 461 camel humps w/1.94s and .030" milled off, edelbrock c3bx intake that was virtually left for dead in my garage, duntov 30/30 solid cam, and 600cfm carb. I've rebuilt this motor several times, and I'm finding out the smaller I go the better it seems to run. No single plane intakes, 2" spacers or 750 carbs. Also, you'll either want to get an msd blaster2 coil or replace points dist with an HEI.
Friend of mine had one in an 80s camaro with a saginaw 4spd behind it. When he got it revvin it would plant you in the seat. Definitly liked the 4spd. We seen the car at the track a few years after he sold it, and found out people had been passing it off as a 327. :D

ap72 09-26-2006 08:50 AM

use a 3.75" stroke crank (400 or 383) to get your displacement up. The smaller bore and longer stroke would be perfect for a truck.

SUPERSTOCK66X 04-24-2008 12:39 PM

the use of a 3.75 crank and a 6" rod makes a smokin engine
combo a friend of mine used this combination in a dirt stock car
with great success i just bought the rotating assembly from him
and will get started on the block clearancing will let you know how
it goes :thumbup:

Double_v23 04-24-2008 01:16 PM

I am sure everyone from 2 years ago will be happy to hear how your project goes.

machine shop tom 04-24-2008 02:52 PM

Even 2 years ago to now, nobody makes a piston to work with a 3.75" stroke crank and a 3.875" nominal bore. If they did, it would be a 359 at .030" over.


ap72 04-24-2008 03:54 PM

just use a 400 rod length

machine shop tom 04-24-2008 06:51 PM


Originally Posted by ap72
just use a 400 rod length

The pistons will hit the head.


ap72 04-24-2008 07:19 PM

yea for some damn reason I though the 307 had a 3.48" stock stroke.. brain fart.

machine shop tom 04-24-2008 07:31 PM


Originally Posted by ap72
yea for some damn reason I though the 307 had a 3.48" stock stroke.. brain fart.

I hate it when that happens to me.


novacrazy2007 04-24-2008 08:42 PM

i had a 307 in my 70 nova also. what i did was i got a set of vortec heads. mine came off of a 97 tahoe. i used a compcams 270h hyd. flat tappet cam. it gives it a nice little rumble. for my intake i got a summit stage one duel plane intake. and a edelbrock 650 carb. hei ignition. i was surprised how much that thing pulled. i did that because the bottom end was still good. but if you have to rebuild it put the money in a 350.

TooMany2count 04-24-2008 10:09 PM

This is where I got my info from when putting my 307 together. I also used a Crane Cam.....joe

All times are GMT -6. The time now is 08:30 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.