The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1969 - 1972 Blazers and Jimmys Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 01-26-2006, 11:53 AM   #1
Jason915
Registered User
 
Join Date: Jan 2005
Location: Colorado Springs
Posts: 693
Those of you with 307 V8's in K5's questions

How many of you have the 307 in your K5 or Jimmy? How do they run power wise are they total dogs, or do they have ok power? Also how do they do on MPG? The reason I ask is becasue I might be able to buy a parts truck with stock rebuilt 2 barrel 307 for $300 the truck don't have a bed and it's rusted bad but I thought I could run the 307 in my K5 to replace the tired 350.
__________________
1971 GMC K1500 SWB Fleetside, 4" skyjacker softride and, 14 Bolt FF, HD Dana 44 4.10's

1970 K5 TBI conversion lifted etc SOLD
1968 C20 camper truck SOLD


“To ban guns because criminals use them is to tell the innocent and law-abiding that their rights and liberties depend not on their own conduct, but on the conduct of the guilty and the lawless.” Jeff Snyder
Jason915 is offline   Reply With Quote
Old 01-26-2006, 11:56 AM   #2
Tynee
I miss this truck.
 
Tynee's Avatar
 
Join Date: Dec 2001
Location: Lexington, KY U.S.A.
Posts: 2,863
Re: Those of you with 307 V8's in K5's questions

run a search for Budget built 307, or something like that on the board. You should turn up a thread with all the opinions on 307's. My buddy is running one in his Jimmy, and it does real well. I don't know what all has been done to it, though.
__________________
'07 GMC Acadia SLT. Sweet ride.

'08 Crew Cab Z-71 short bed. Really like this truck A LOT.
Tynee is offline   Reply With Quote
Old 01-26-2006, 01:12 PM   #3
Yukon Jack
Post Whore
 
Yukon Jack's Avatar
 
Join Date: Feb 2000
Location: Rose Hill, KS, USA
Posts: 12,683
Re: Those of you with 307 V8's in K5's questions

Not exactly specific to your question but my 69 K20 had a 307 in it when I bought it. It had good torque and handled pulling loads pretty well. I think they are seen as not worthwhile for making lots of hp but do make decent torque. I figured the mileage once at about 9 mpg.
__________________
1970 Blazer with a 400 sbc and 4" lift
1980 Pontiac Trans Am, 455 Oldsmobile
2012 Kawasaki Concours 14
Yukon Jack is offline   Reply With Quote
Old 01-26-2006, 01:53 PM   #4
Old Dave
Is a bullfrog waterproof?
 
Old Dave's Avatar
 
Join Date: Nov 2000
Location: OLATHE, KANSAS
Posts: 1,130
Re: Those of you with 307 V8's in K5's questions

I worked for a plumber the summer after I got out of high school that had a 68 Chevy pickup that had a 307 with a 3-speed. Truck was only a year old and had about 25K on it. It would bark the tires in 1st and 2nd and ran great, but it drank a quart of oil about every 600 miles but didn't smoke and didn't leak. It had plenty of power and got 8 MPG and it didn't matter if you had a small box of plastic pipe fittings in bed or pulling the backhoe or trencher. Of course gas was $.27 a gallon and oil was $.35 a quart, so he didn't care.
__________________
"It is better to remain silent and be thought a fool, than to open one's mouth and remove all doubt."

Ben Franklin

__________________
1970 Chevy shortbed
2002 Harley Custom Chopper (Long sucker)
1998 K2500 5.7L 5-speed Longbed
1st two are My son's toys...they just live in my garage!
1997 GMC K1500 Suburban
1993 S-10 Blazer 4D (youngest son's daily driver)
2000 Dodge Ram 4WD Ext. Cab (5.9L)
Wife is a late year 1951
Old Dave is offline   Reply With Quote
Old 01-26-2006, 02:25 PM   #5
Rydn2L0w
Active Member
 
Rydn2L0w's Avatar
 
Join Date: Nov 2005
Location: Orlando, Fl.
Posts: 123
Re: Those of you with 307 V8's in K5's questions

I have a 307 in my 69 suburban, what a terd! Id say stay far away from it! You can build a much healthier 350 forthe same amount of money.
Rydn2L0w is offline   Reply With Quote
Old 01-27-2006, 11:08 AM   #6
Gary 70 Jimmy
Senior Member

 
Gary 70 Jimmy's Avatar
 
Join Date: Jan 2002
Location: Burghill, Ohio 44404
Posts: 3,401
Re: Those of you with 307 V8's in K5's questions

I had a 68 1/2 with a 307 then I put it in a 67 3/4 both had 4 speeds with a granny gear with 456 rear ends had a lot of take off power but top speed was only 70. Then I put it in a 72 3/4 with an automatic and it had no power bottom end or top end. Most reliable motor I ever had I still have the motor sitting in my garage waiting for its next truck.
Gary 70 Jimmy is offline   Reply With Quote
Old 01-27-2006, 09:19 PM   #7
RANDY COX
Registered User
 
RANDY COX's Avatar
 
Join Date: Mar 2001
Location: RADFORD, VA
Posts: 2,651
Re: Those of you with 307 V8's in K5's questions

My ex blazer had a 307 in it with 2 barrell 4x4 been rebuilt and it had plenty of power 4"lift and 35's that thing would move on purdy good.
__________________
1964 BBC 402 4x4
RANDY COX is offline   Reply With Quote
Old 07-26-2006, 08:42 PM   #8
Rydn2L0w
Active Member
 
Rydn2L0w's Avatar
 
Join Date: Nov 2005
Location: Orlando, Fl.
Posts: 123
Re: Those of you with 307 V8's in K5's questions

My 307 probably had a million miles on it too. Was more cost effective to yank it and drop in a used 94 Caddy 350.
Rydn2L0w is offline   Reply With Quote
Old 07-26-2006, 08:51 PM   #9
Dick Dale
Excelsior, You Fathead.
 
Dick Dale's Avatar
 
Join Date: Jun 2004
Location: Valparaiso, In
Posts: 937
Re: Those of you with 307 V8's in K5's questions

Change to a better cam and get a 4 barrel. Remember, it is still a SBC and will make power if you do it right. If it has a fresh rebuild, you can tweak it and make it run well.
__________________
Go Navy. The Sea Is Ours.
Budget 350 Build
http://67-72chevytrucks.com/vboard/s...38#post2264638
Dick Dale is offline   Reply With Quote
Old 07-26-2006, 09:20 PM   #10
pissonNOS
senior member
 
pissonNOS's Avatar
 
Join Date: Feb 2003
Location: fort macleod alberta
Posts: 2,770
Re: Those of you with 307 V8's in K5's questions

Quote:
Originally Posted by Dick Dale
Change to a better cam and get a 4 barrel. Remember, it is still a SBC and will make power if you do it right. If it has a fresh rebuild, you can tweak it and make it run well.
I couldnt agree more i have a 307 that ive done .030 292 blue racer cam edelbrock intake carter 625 carb msd 6A box Mallory HEI headers and just for kicks put on a K&N u can ask fellow board member slammed 66 how well it pulled with 4 guys in the cab this motor is very reliable for me and i live it also it sounds cooler when telling people what you have than telling them you have a bellybutton 350 no offense to anyone with a 350 im just saying
__________________
69 GMC bagged
pissonNOS is offline   Reply With Quote
Old 07-26-2006, 09:49 PM   #11
tom71
what happened to flint mi
 
tom71's Avatar
 
Join Date: Oct 2005
Location: san diego
Posts: 437
Re: Those of you with 307 V8's in K5's questions

i ve got a 307 with 100,000 original miles on it in a 71 k5 it doesnt leak a drop of fluid , makes plenty of torque and will squeel the tires i put a edelbrock 650 and performer intake and put headers and exhaust on it , runs like a champ id say if the motor is clean than go for it but if its tired in any way well then just rebuild your 350 youll be happier i ve got a 350 in my 72 k5 (the avatar pic )and its got way more power . i run the same carbs on both and they both have headers and exhaust .
__________________
71 swb 2wd fleet frame off in progress
72 4x4 blazer daily driver
70 olds cutlass s mint condition owned by a grandma
56 gmc 2wd project waitng
97 fiance mobile
tom71 is offline   Reply With Quote
Old 07-27-2006, 09:07 AM   #12
lawricker
Registered User
 
lawricker's Avatar
 
Join Date: Jul 2006
Location: texas
Posts: 56
Re: Those of you with 307 V8's in K5's questions

My experience has been the 307 will not last as long as the 350. There may be exceptions, but normally that is what I see. the gas mileage will be better in the 350. It wont work as hard as the 307 to pull, drive, etc. Oh you can cam it, carb it etc and get some pretty good horsepower. It is sort of like a Dodge..works ok, just don't want anyone to know you have one.....
__________________
Retired and working my tail off..
lawricker is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 10:10 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com