Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: 305 Parts recommendation/for sale

  1. #1
    Senior Member Carroll Shelby Rob Liebbe's Avatar
    Join Date
    Mar 2006
    Location
    Magnolia/Woodlands, Texas
    Posts
    2,706

    305 Parts recommendation/for sale

    This might sound strange, but I am looking to slightly improve the 307 that is in my 70 Chevelle.

    The camshafts in these engines are known to have high wear causing lower performance and high fuel consumption and likely needing replacing by 50,000 miles. My car has these issues at its current 37,000 original miles.

    I'm thinking about 305 heads for a compression increase and a cam that has good idle and makes decent torque. I already dumped the two barrel carb and iron intake for a 600 cfm spread-bore Holley on an Edlebrock Performer alum intake.

    I know, I know, upgrade to a 350, but the car is a low mileage "family heirloom" with a Powerglide and 3.00 (I think ) rear gears. I just want to make it drive a little better and on a budget.

    Any thoughts from the 305 gurus?

    Rob Liebbe
    Attached Images Attached Images
    Rob Liebbe - Texas Region
    Camaro, Mustang, doesn't matter to me, I'll race it.

  2. #2
    Senior Member Grass-Passer
    Join Date
    May 2012
    Location
    Pearland.TX
    Posts
    463
    I have the 305 that came out of my race car, it needs to be rebuilt but the heads were good in shape.

  3. #3
    Senior Member Carroll Shelby
    Join Date
    Feb 2007
    Location
    Plano
    Posts
    1,983
    Blog Entries
    2
    Read this link from an engine buddy of my dads. I think they said the 307 can be similar to a 283 with a head/cam swap and should run pretty decent. But then you also might need to change the torque converter. Checking the rear gear ratio and going lower is going to really help the takeoff with a small engine. Then if you want to do a lot of highway driving put in an overdrive. I don't remember the dimensions of a PG but a 200r4 is the same length as a TH350.

    For not much more money I would consider getting a whole motor. I understand the sentimental low mileage but consider pulling the original motor out to save it and put in a better motor. Heads/cam is probably going to run you what $500 and a lot of labor which you still have a worn out 307. I bet you can find a decent motor complete for $500-you just need a long block.

    Here is a link the guy sent me to read about some 307 changes.
    http://www.chevelles.com/forums/18-e.../topics/214329
    Bryan Leinart
    CMC #24

  4. #4
    Senior Member Carroll Shelby Supercharged111's Avatar
    Join Date
    Jun 2014
    Location
    Colorado Springs, CO
    Posts
    1,149
    The Vortec truck motors are dirt cheap and run circles around the older stuff. Still GenI too no retrofitting, just need a compatible intake. They use more modern gaskets too and leak a lot less.They come as a 305 or 350. IMO once you yank those garbage heads the originalness is gone so why keep the 307 in there?
    RM CMC Director

  5. #5
    Senior Member Carroll Shelby Rob Liebbe's Avatar
    Join Date
    Mar 2006
    Location
    Magnolia/Woodlands, Texas
    Posts
    2,706
    Quote Originally Posted by Supercharged111 View Post
    The Vortec truck motors are dirt cheap and run circles around the older stuff. Still GenI too no retrofitting, just need a compatible intake. They use more modern gaskets too and leak a lot less.They come as a 305 or 350. IMO once you yank those garbage heads the originalness is gone so why keep the 307 in there?
    OK - what year did the Vortec 305/350's go into the trucks? And what years use the old style intake manifolds?
    Rob Liebbe - Texas Region
    Camaro, Mustang, doesn't matter to me, I'll race it.

  6. #6
    Senior Member Grass-Passer
    Join Date
    May 2012
    Location
    Pearland.TX
    Posts
    463
    Quote Originally Posted by Rob Liebbe View Post
    OK - what year did the Vortec 305/350's go into the trucks? And what years use the old style intake manifolds?
    96 was the first year for the 5.7L and 5.0L Vortec CPFI small block V8s

  7. #7
    Senior Member Carroll Shelby Supercharged111's Avatar
    Join Date
    Jun 2014
    Location
    Colorado Springs, CO
    Posts
    1,149
    Quote Originally Posted by Rob Liebbe View Post
    OK - what year did the Vortec 305/350's go into the trucks? And what years use the old style intake manifolds?
    96-98 (99 as the classic, not very common) in the half tons, they lived until 2000 in the 8 lug chassis, and until 2002 in the vans. You can get intakes pretty cheap on Summit too.
    RM CMC Director

  8. #8
    Senior Member Carroll Shelby marshall_mosty's Avatar
    Join Date
    Mar 2006
    Location
    Denton, TX
    Posts
    3,333
    Regarding the PG to 200R4, there are conversions available. That is what I'm planning on for my '57 to get rid of the "glide".
    Marshall Mosty
    AI/SI Texas Regional Director
    2011 NASA-TX American Iron Champ
    AI #67 "Mosty Brothers' Racing" (RIP)
    ST6 #21 Toyota Corolla (being revived)...

  9. #9
    Senior Member Carroll Shelby Rob Liebbe's Avatar
    Join Date
    Mar 2006
    Location
    Magnolia/Woodlands, Texas
    Posts
    2,706
    Quote Originally Posted by marshall_mosty View Post
    Regarding the PG to 200R4, there are conversions available. That is what I'm planning on for my '57 to get rid of the "glide".
    Th Powerglide is neat in a nostalgic/unique kind of way with only one shift but first gear is more like a second gear an TH350 of 200R4.
    Rob Liebbe - Texas Region
    Camaro, Mustang, doesn't matter to me, I'll race it.

  10. #10
    Senior Member Carroll Shelby
    Join Date
    Feb 2007
    Location
    Plano
    Posts
    1,983
    Blog Entries
    2
    For off the line pep the biggest change would probably be the transmission or rear gear. 3.00 and a PG will sure take awhile before the revs get up much and by that time you are already going the speed limit when it shifts. 700r4 has a pretty low first gear.
    Bryan Leinart
    CMC #24

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •