Burnt valve 350...fix or swap to 383, 454, 6bt?

Discussion in 'Engine Swaps (Gas) LS, Vortec, LT1 , etc.' started by Warkmeister, Jun 12, 2018 at 3:18 PM.

  1. Warkmeister

    Warkmeister Junior Member

    Posts:
    14
    Likes Received:
    10
    Joined:
    May 10, 2018
    Location:
    Sanger, CA
    First Name:
    Kyle
    Truck Year:
    1981
    Truck Model:
    K30
    Engine Size:
    350
    hey guys, I just gotta say first off, you all are a fantastic group of individuals. I’ve asked a few questions already to get my 81 CCLB project up to speed, and they’ve all been met with a high degree of human decency that lacks at other sites...you all know where I mean.

    To the question!

    I know my 350 has burnt valves on both banks, lub sounds dollar bill test and true dual exhaust told me so. I like to think about long term goals and fix short term issues accordingly. I can drive it, but it needs fixed and I need more power. Here are my options as I see them:
    1. $500 or less gets me fixed heads, used aftermarket or performance GM heads.
    2. $500 or less also gets me an 86 c2500 with 454 of unknown condition, but is mated to an sm465 just like my current motor. I know the owner and have already agreed on price of $400, all I need to do is pay him and drag it home. Truck has 96k on it, ran when parked, and has been sitting for 15-20yrs.
    3. $500 or more gets me a new crank and more, and starts me on the path of building a stroker 383, obviously more costs after that to finish the build.
    4. ?$ gets me a 12v Cummins and I get to learn the work associated with that swap.

    I’ve never swapped a motor, this is my first sbc and squarebody, and I’m pretty mechanically inclined, albeit inexperienced in these areas. I’ll dive in to almost anything in order to learn.
    My goals are to have a fun driver that can haul ass (-ish....1tons only go so fast), the kids, and trailers/rvs when called upon. Not a daily driver, but something that is always at the ready for just about anything. I want to stay manual too. I’d love to crest the 400hp/tq mark in either option. 400lbft is nice in our Tundra as a benchmark, but it’s getting sold.
     
  2. Craig 85

    Craig 85 Supporting Member Supporting Member

    Posts:
    898
    Likes Received:
    421
    Joined:
    Jan 25, 2017
    Location:
    Grass Valley, CA
    First Name:
    Craig
    Truck Year:
    1985
    Truck Model:
    K30 SRW
    Engine Size:
    454/TH-400/NP205
    I assume Sanger is in the bi-annual smog area. With that said, if you go the 454 route, you need to decide what smog year you want to go with 81 or 86.

    454's break down from 1981 to 12/31/84 and 1/1/85 to the end of 1986 production. My truck is an '85, but falls under the 1984 smog specs due to its build date. The '86 is a dual smog pump motor, but runs factory stainless exhaust headers (photo). Finding parts used for only 1 1/2 years could be problematic. So take everything related to the engine and that has a vacuum line hooked up to it.

    If you stick with 81 smog specs, I don't know if all the small block parts are compatible to a big block of the same year. most brackets are different. I know I had to do a 9 hour road trip to buy discontinued smog parts from a guy in Dinuba that parted out a motor home.

    [​IMG]
     
    animal likes this.
  3. Warkmeister

    Warkmeister Junior Member

    Posts:
    14
    Likes Received:
    10
    Joined:
    May 10, 2018
    Location:
    Sanger, CA
    First Name:
    Kyle
    Truck Year:
    1981
    Truck Model:
    K30
    Engine Size:
    350
    Considering your reply, I forgot to mention, this was a factory diesel, so no smog! Very thorough though, and valuable info. Thanks.
    My plan with the bbc would be no smog stuff, so just an intake initially, then mild cam, headers, and oval heads or other good flowing units, nothing crazy.
    Knowing that, would you still vote 454?
     
  4. DoubleDingo

    DoubleDingo Unconventional Thinker

    Posts:
    2,048
    Likes Received:
    260
    Joined:
    Jul 3, 2012
    Location:
    California
    First Name:
    Shane
    Truck Year:
    1981, 1965
    Truck Model:
    81-C20 Silverado Camper Special, 65-C20 with 4:57 gears and Borg Warner Overdrive
    Engine Size:
    Carb'ed Vortec 350, 1972 L48 350
    You need to make sure there isn't any back fees on that vehicle. If it's been sitting non-op, you're golden. Non non-op, you'll be paying a huge amount in back fees.
     
  5. yevgenievich

    yevgenievich Full Access Member

    Posts:
    2,459
    Likes Received:
    472
    Joined:
    Mar 1, 2014
    Location:
    Texas
    First Name:
    Viktor
    Truck Year:
    1991
    Truck Model:
    V2500 burb
    Engine Size:
    5.7
    454 sounds like an easily economical swap without too much of complications and would archieve desired goals(might have to add heads/cam to really archieve desired goals)
     
    K10eddie likes this.
  6. Warkmeister

    Warkmeister Junior Member

    Posts:
    14
    Likes Received:
    10
    Joined:
    May 10, 2018
    Location:
    Sanger, CA
    First Name:
    Kyle
    Truck Year:
    1981
    Truck Model:
    K30
    Engine Size:
    350
    The 86 parts truck would never be registered again, unless I’m misunderstanding you, so no worries there. Back fees only apply if not renewed within 7 years. After 7, it’s s new title. At least that’s how it’s worked in the past with the motorcycles I’ve restored. I’d pull the big block and scrap the rest. If it all works out, $400 for a running 454 with tranny plus a pile of parts is more than worth it.

    Thanks again for the advice and info youve all offered.
     
    K10eddie likes this.
  7. Rusty Nail

    Rusty Nail Build the wall - deport them all!

    Posts:
    2,551
    Likes Received:
    857
    Joined:
    Jan 29, 2015
    Location:
    America
    First Name:
    Rusty
    Truck Year:
    1977
    Truck Model:
    C20
    Engine Size:
    350
    Repairing heads is both easy AND fun, there is no good reason to not do that.
    A $400 complete BB "parts truck" that MAY run with a little tinkering and a battery?
    Again, no good reason to not do that.

    400HP is a very lofty goal :imo: i think after you get these "smaller" goals knocked out, they may build hella confidence while you try to save some cash! Cuz you're gonna need it brother! :D
     
  8. Craig 85

    Craig 85 Supporting Member Supporting Member

    Posts:
    898
    Likes Received:
    421
    Joined:
    Jan 25, 2017
    Location:
    Grass Valley, CA
    First Name:
    Craig
    Truck Year:
    1985
    Truck Model:
    K30 SRW
    Engine Size:
    454/TH-400/NP205
    FYI the '86 454 has a 7.9 compression ratio with peanut port heads.
     
  9. 4WDKC

    4WDKC Full Access Member

    Posts:
    1,457
    Likes Received:
    553
    Joined:
    Jan 27, 2016
    Location:
    Illinois
    First Name:
    Kacy
    Truck Year:
    1987
    Truck Model:
    V10
    Engine Size:
    350
    I know you are focusing on the engine right now but keep in mind your trans also, reason is the truck likely has 410 gears and no overdrive is going to be high rpm slow speed. If you want to see what its like look up the gears in your tundra and the trans to find if a gear other than D is 1:1 then make a drive like that. Back to the engine honestly I wouldnt spend a dollar on smog heads when there are much better options that could be used. Look for good used heads before repairing, $400 is hard to beat for a big block truck, that said maybe get it running to make sure the engine doesnt need rebuilt.
     
  10. DoubleDingo

    DoubleDingo Unconventional Thinker

    Posts:
    2,048
    Likes Received:
    260
    Joined:
    Jul 3, 2012
    Location:
    California
    First Name:
    Shane
    Truck Year:
    1981, 1965
    Truck Model:
    81-C20 Silverado Camper Special, 65-C20 with 4:57 gears and Borg Warner Overdrive
    Engine Size:
    Carb'ed Vortec 350, 1972 L48 350
    If it's being scrapped then it shouldn't be an issue. I've never heard of the 7 year rule as you mentioned, but if that's how it works that's cool. I guess it's a common law type of thing like living with a girlfriend for 7 years you're now married to her...lol... But yeah, getting a good engine and trans and miscellaneous parts for $400 and no title troubles, sounds like a good deal to me.
     
  11. K10eddie

    K10eddie Junior Member

    Posts:
    15
    Likes Received:
    4
    Joined:
    May 27, 2018
    Location:
    Connecticut
    First Name:
    Ed
    Truck Year:
    1979
    Truck Model:
    K10
    Engine Size:
    383
    I would 100% get the bbc truck. Swap the 454 into your current truck, sell the sm465 for decent coin (unless you wanted to keep it) and part the 454 truck out for spare parts and stuff to sell.

    Personally while the 454 is out, I would swap to closed chamber heads, refresh the valvetrain, gaskets and send it. Unless you wanted to put a new cam in it, then do that too.
     
    Last edited: Jun 17, 2018 at 7:50 AM

Share This Page