Author Topic: SM465 clutch question  (Read 2558 times)

Offline Flyinhillbilly

  • Newbie
  • Posts: 77
SM465 clutch question
« on: August 20, 2015, 11:52:42 AM »
Hi, I have an 84 K20 with a 350/SM465 and I was wondering if any of you guys knew if it was an 11" or 12" clutch? I'm putting together a new engine combo for it and I'm trying to get as much done as possible before installing it. Thanks in advance for any help.
I was born on a mountian, raised in a cave,
Overpowered cars is all I crave.

Offline 1967KaiserM715

  • Junior Member
  • ***
  • Posts: 914
  • 1985 GMC K1500 w/ 6.5 TD
Re: SM465 clutch question
« Reply #1 on: August 20, 2015, 12:24:31 PM »
I,'ve seen both 11 and 12, I would go larger for better grip, especially with a new/built engine
Current Vehicles:1985 GMC K10(Daily) 1991 GMC K2500(Daily) 1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
 1986 Chevy K30(under repair)

Offline Don5

  • Registered Users
  • *
  • Posts: 229
  • Newbie
Re: SM465 clutch question
« Reply #2 on: August 20, 2015, 02:02:40 PM »
I have always used the Heavy Duty 12 inch 3 finger clutch in my truck. Make sure you replace the pilot bushing too.
It's been a LONG time since I have been called a newbie. Just sayin....

1979 GMC K15 355, SM 465, 205, 3.73 Dana 44 with a Spartan Locker, 12 bolt Eaton limited slip and 6 inch lift with 36 x 12.50 Super Swamper TSL's.

Offline Flyinhillbilly

  • Newbie
  • Posts: 77
Re: SM465 clutch question
« Reply #3 on: August 20, 2015, 04:02:36 PM »
Thanks guys, I'm putting a turbocharged 6.0 in it, so if they will both fit I think 12" is definitely the ticket.
I was born on a mountian, raised in a cave,
Overpowered cars is all I crave.

Offline Captkaos

  • OWNER and Administrator
  • Administrator
  • Senior Member
  • *****
  • Posts: 18376
    • http://www.73-87chevytrucks.com
Re: SM465 clutch question
« Reply #4 on: August 20, 2015, 09:51:19 PM »
The PN for the factory GM bell for a 12" has a specific PN.  What is yours?

Offline Flyinhillbilly

  • Newbie
  • Posts: 77
Re: SM465 clutch question
« Reply #5 on: August 21, 2015, 11:29:27 AM »
The PN for the factory GM bell for a 12" has a specific PN.  What is yours?
No idea, it's in the truck and covered in grease. I guess I'll take my creeper to the car wash. Where would the #'s be on the bellhousing?
I was born on a mountian, raised in a cave,
Overpowered cars is all I crave.

Offline roundhouse

  • Senior Member
  • ****
  • Posts: 1474
  • Newbie
Re: SM465 clutch question
« Reply #6 on: August 22, 2015, 07:25:50 PM »
With a turbocharged 6.0 you seriously need a slick shifting 5 or 6 speed


Sent from my iPhone using Tapatalk

Offline roundhouse

  • Senior Member
  • ****
  • Posts: 1474
  • Newbie
Re: SM465 clutch question
« Reply #7 on: August 22, 2015, 07:31:46 PM »

With a turbocharged 6.0 you seriously need a slick shifting 5 or 6 speed

The NV3500 is great but not sure how it would hold up to that kind of power


Sent from my iPhone using Tapatalk


Sent from my iPhone using Tapatalk

Offline Flyinhillbilly

  • Newbie
  • Posts: 77
Re: SM465 clutch question
« Reply #8 on: August 22, 2015, 07:37:57 PM »
It's just a toy, my daily, but not a race car. The 465 should be my best chance at holding the power. I'm only trying for 500ish rwhp.
I was born on a mountian, raised in a cave,
Overpowered cars is all I crave.