Thoughts on building 1998 454

Discussion in 'The Engine Bay' started by Upstate, Aug 4, 2015.

  1. Upstate

    Upstate 1/2 ton status

    Joined:
    Aug 16, 2010
    Posts:
    951
    Likes Received:
    32
    Location:
    New York
    Build(s):
    1
    I have a good chance on buying at a reasonable price a high mileage complete truck with a 454 / 4l80 combo. Any input on the 1998 454 as far as interchanging BBC parts and capabilities? Motor and tranny run excellent.


    Thanks
     
  2. bigblock72

    bigblock72 Elmer's glue taste tester Premium Member GMOTM Winner

    Joined:
    Oct 18, 2005
    Posts:
    1,383
    Likes Received:
    180
    Location:
    American Fork, Utah
    Do it!!! The 96 up (gen 6) big blocks work well, have factory roller cams, decent heads, way strong bottom ends etc. Mark IV heads bolt on with no head gasket issues like the gen 5s had. They still have non-adjustable valve train like the gen 5s, but can be converted if necessary.

    The PCMs work ok on the 98-00 if you want to keep the EFI and 4l80, or it's fairly straight forward to go to the later LS computer for better support.
     
    bsgreen and Smokinthehippies like this.
  3. Upstate

    Upstate 1/2 ton status

    Joined:
    Aug 16, 2010
    Posts:
    951
    Likes Received:
    32
    Location:
    New York
    Build(s):
    1
    I have a MSD Atomic that I would use. Any issues with aftermarket intakes?
     
  4. GWeakland620

    GWeakland620 THE CK5 Crayon Eater Premium Member GMOTM Winner

    Joined:
    Sep 15, 2010
    Posts:
    13,851
    Likes Received:
    12,211
    Location:
    Toe-peek-ugh, KS
    Build(s):
    4
  5. bigblock72

    bigblock72 Elmer's glue taste tester Premium Member GMOTM Winner

    Joined:
    Oct 18, 2005
    Posts:
    1,383
    Likes Received:
    180
    Location:
    American Fork, Utah
    No issues with intake manifolds, the MSD system will work good and save some headaches.
     
  6. Upstate

    Upstate 1/2 ton status

    Joined:
    Aug 16, 2010
    Posts:
    951
    Likes Received:
    32
    Location:
    New York
    Build(s):
    1
    The motor has 260K on it but runs excellent and no smoke. $900 for the whole truck. Thoughts?
     
  7. bigblock72

    bigblock72 Elmer's glue taste tester Premium Member GMOTM Winner

    Joined:
    Oct 18, 2005
    Posts:
    1,383
    Likes Received:
    180
    Location:
    American Fork, Utah
    It's not in your driveway because??????????????:D:thumb:


    I've pulled apart 300k plus big blocks that that weren't maintained that well and found minimal wear, simply re-ringed and re-bearinged them and they went another 100k before the customer sold them still running.
     
    Big Ray likes this.
  8. TDAWG1

    TDAWG1 1/2 ton status Premium Member

    Joined:
    Jan 18, 2005
    Posts:
    2,837
    Likes Received:
    8
    Location:
    Grand Junction, Crawlorado
    I'm in the process of doing this. The L29 platform seems to be great. I am hearing about the injectors leaking though... Anyone having This issue?
     
  9. Ten_Bucks

    Ten_Bucks 1/2 ton status

    Joined:
    Dec 9, 2004
    Posts:
    901
    Likes Received:
    57
    Location:
    Placerville, California
    Super Chevy magazine is doing a series of articles showing how strong the stock L29 454 is. In the first article, they put a Holley carb on it with a mild nitrous kit. It made 500hp with nitrous. Then they did a cam swap and some head work. Within the next couple months, they will be throwing boost at it. This is all on the stock pistons, rods, crank, rod and main bearings. Its a very stout engine for not being a Chevy Performance crate engine. The whole series of articles is also showing what can be done with the engine on a budget.

    Scott
     
    Capt Ron and Smokinthehippies like this.
  10. Ten_Bucks

    Ten_Bucks 1/2 ton status

    Joined:
    Dec 9, 2004
    Posts:
    901
    Likes Received:
    57
    Location:
    Placerville, California
  11. Ducshak

    Ducshak Registered Member Premium Member

    Joined:
    Apr 29, 2013
    Posts:
    57
    Likes Received:
    8
    Location:
    Idaho
    I am also in the early stages of building a 97' 454. Mine was only the short block so no factory fuel injection. I am learning what will interchange with the old Mark IV and what won't. The roller cam is a plus along with the 4 bolt mains. I will be going with a carb and getting a set of aftermarket aluminium heads for it. I will be following this thread as well.
     
  12. Kay86K5

    Kay86K5 1/2 ton status Premium Member GMOTM Winner

    Joined:
    Mar 9, 2012
    Posts:
    3,533
    Likes Received:
    3,629
    Location:
    Emmett, ID
    Build(s):
    3
    I have a 1996 K2500 with the L29 7.4l 454. I had to finally replace my factory injectors at 170,000+ miles on them. I now only have about 182,000+ on the truck but no problems so far. After doing some reading, it's a pretty common problem, and the other problem is they are pretty expensive, even just for factory replacements. If you get the upgrades (I think they are Bosch) they are really expensive. My motor is 100% stock so I just went with factory upgrades and called it good. Most people change the fuel pressure regulator while you have the plenum (spel?) off since it's right there on the back of the motor next to the injectors. It's worth it to do both at the same time if you are doing it. But to be honest it's not a horrible job.

    I have loved my L29 truck. My only problem is the truck is just an extended cab with no door access to the back and I just had my third kid. That's why I just purcahased a 1989 V3500 crew cab that I am going to build into my new tow rig. A part of me wants someone to hit me in my current truck so I can take the money and the motor and swap it into my crew cab, haha. But as of now I am looking for an 8.1 to drop into it. But I think these L29's are sweet motors that with just a little fine tuning can produce a lot.
     
    TDAWG1 likes this.
  13. TDAWG1

    TDAWG1 1/2 ton status Premium Member

    Joined:
    Jan 18, 2005
    Posts:
    2,837
    Likes Received:
    8
    Location:
    Grand Junction, Crawlorado
    Thanx for the info
     
  14. rdn2blazer

    rdn2blazer 1 ton status Vendor

    Joined:
    Jun 9, 2004
    Posts:
    21,061
    Likes Received:
    6,322
    Location:
    So Cal.
    Glad I came across this old thread. I have a 96' 454 I could not decide if I wanted to rebuild or just pop for a turnkey motor. Think I'm going to go thru this complete motor and upgrade the harness to LS setup. It's going in my 73' so it's all smog exempt. Going to get built for sure.
     
    Kay86K5 likes this.
  15. Earldub21

    Earldub21 Registered Member Premium Member

    Joined:
    Apr 9, 2018
    Posts:
    18
    Likes Received:
    3
    Location:
    Oak Harbor, WA
    does anyone know of any headers you can use with the L29 engine with a NV4500 with an external slave cylinder? I am doing this swap once I return.
     
  16. Bent77

    Bent77 lil meanie Staff Member Moderator GMOTM Winner

    Joined:
    Dec 3, 2002
    Posts:
    26,103
    Likes Received:
    31,968
    Location:
    NoCo
    Build(s):
    1
    @Capt Ron might know something. He went 8.1 with the 4500, think he has factory manifolds
     
  17. nvrenuf

    nvrenuf Next weekend... Premium Member

    Joined:
    Jan 7, 2002
    Posts:
    16,560
    Likes Received:
    3,310
    Location:
    Mobile, Al.
    Build(s):
    1
    I'm running a set of Sanderson shorties on my Blazer, they fit great and plenty of clearance for the external slave on my SM465.

    That said, other members here have had fitment issues with the same headers.
     
  18. mrk5

    mrk5 The Sticker Guy Moderator GMOTM Winner Author

    Joined:
    Apr 20, 2004
    Posts:
    17,774
    Likes Received:
    8,009
    Location:
    Northern Colorado
    Build(s):
    2
    I think Ron has the L29 454.
     
    Capt Ron and beags86 like this.
  19. Bent77

    Bent77 lil meanie Staff Member Moderator GMOTM Winner

    Joined:
    Dec 3, 2002
    Posts:
    26,103
    Likes Received:
    31,968
    Location:
    NoCo
    Build(s):
    1
    Can’t keep track of you fat block guys! Fat motor clutch is all I remember!
     
    Capt Ron and mrk5 like this.
  20. Earldub21

    Earldub21 Registered Member Premium Member

    Joined:
    Apr 9, 2018
    Posts:
    18
    Likes Received:
    3
    Location:
    Oak Harbor, WA
    do you know what model they are? are those for big blocks?
     
    Last edited: Sep 11, 2019

Share This Page