Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Att. Ken (Engine Question)

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Andreas, Jul 6, 2000.

  1. Andreas

    Andreas 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    188
    Likes Received:
    0
    Location:
    Sweden
    How would you build a 406 for good all around performance ? My Blazer will see a bit more street than mud, and I don´t wanna change converter so I´ll stay as "mild" as I can[​IMG]. My plan so far is as follows:
    Stock pistons (to go with my ported 2.02&1.6 valves 60 cc 283 heads already sitting on the 406, this should get the comp to just below 10:1)
    Comp cams magnum 270 and hydraulic lifters
    Crane roller rocker arms & stud girdles
    Performer intake (Maybe performer RPM)
    HV oilpump and bigger pan
    Haven´t decidet what carb yet. I already got a Qjet (4MV) and a Holley 600.
    I´ll stick with the shorter 5.565" rods, although I got a 350 (in zillion pieces)standing by. For me it´s too much hassle to rebalance it with 5.7" rods (I´m living in Sweden, remember?[​IMG] Engine shops doesn´t exactly grow on trees here).
    Double roller timing chain
    Headers of course.
    Engine oil cooler.
    New alu water pump (Moroso)
    I´ve probably forgot to mention something, anyway, you get the big picture[​IMG]. I´m estimating this engine will push some 350-370 hp and 420-450 ft.lbs. @ 4000 rpm (flywheel horsies). Anything vital you like to add...or subtract[​IMG] ? Btw, right now the 406 has got forged 13:1 pistons and a Torker 2 intake, dunno what cam profile. Not exactly the right stuff for a 5000lbs car running on 96 octane...and with cast iron heads.
    Of course everybody who´s got some tips are very welcome to answer, not just Ken

    Andreas

    406cui of pure sh*t[​IMG]
     
  2. Executioner

    Executioner 1/2 ton status

    Joined:
    Feb 22, 2000
    Posts:
    1,530
    Likes Received:
    0
    Location:
    Temp. Ft. Walton Beach Fl. home=Tucson, Az.
    With that weight and tires and gears your running(40-44, 3.73:1), you will need torque down low to get the Blazer moving. You need to build low end TQ like 350+ at 1,500 to 1,800 rpms.
    Good luck
     
  3. Andreas

    Andreas 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    188
    Likes Received:
    0
    Location:
    Sweden
    Oops, I should change my bio[​IMG]. I will settle with 38"5 SSR´s or Mickey Thompson, preferbly MT since they have more of an on-road friendly thread. Maybe they don´t last any longer than Super Swampers but I suspect they behave better on pavement?. Also, I´m currently looking at an Eaton 3/4 ton rear with 4.56 ratio. Maybe I won´t buy it (because of lack of spare parts) but I´ll atleast stay in that ratio and strenght range. And finally, an engine with the parts I mentioned above will produce good torque at low rpms too, I wont have to back off timing due to the fact I can get 98 octane leaded fuel here in Sweden. I might even have to advance the timing because the cam requires it......D*mn, I STILL feel I forgot to mention something [​IMG]

    Andreas

    406cui of pure sh*t[​IMG]
     
  4. ken

    ken 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    1,244
    Likes Received:
    0
    Location:
    Anaheim, CA
    I don't like the idea of 2.02/1.60 heads for street/torque use. They'll work fine, but will give up some low-end. Also, are they really 283 heads? Cuz usually 283 heads came with REAL SMALL valves, like 1.72x1.40/1.50"...so if your heads were that size and have been opened up to 2.02, they can't be that efficient, meaning they must be fully ported to extract the added value of the larger valves. The compression is high for here in the U.S., but if you've got that high of octane fuel in Sweden then by all means exploit it with higher compression! Good idea to use the Performer, and I would use the Q-Jet rebuilt. Much better carb than the Holley or Edelbrock/Carter AFB! The 270 cam is about right for your power aspirations. The short rods will be fine, max reliable RPM will be 6,000, but why turn it faster??? Higher RPMS are for winding motors like 283s and 327s, which need to wind to make power. Your 406 won't need to wind to make power. Anyway, building an engine to wind out kills the bottom end anyway. Leave the winders to the drag racing set! As for the Eaton rear end, they usually NEVER go bad, as they are HUGE! If you can get a deal on one, I would buy it. I have one with 5.14 gears in it...can't hardly seem to give it away, so it sits rotting in my backyard.

    ken
     
  5. Andreas

    Andreas 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    188
    Likes Received:
    0
    Location:
    Sweden
    Ken. According to http://www.mortec.com/ my heads are from a 283. I saw on some other website that they also could be from a 327. Casting # is 3884520, if I remember correctly. Anyway, they are "very" (fully) ported and has new valveguides, so I´ll stick with them, torque-loss or not. It can´t be THAT much anyway[​IMG]
    About the crankrods. I´ve read somwhere that the safe limit with 5.565" rods is around 4500rpm, not 6000 like you say. If you are correct and the other guy is wrong I´ll sleep much better[​IMG], ´cause 4500 rpms seems a little bit on the low side.

    Andreas

    406cui of pure sh*t[​IMG]
     
  6. ken

    ken 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    1,244
    Likes Received:
    0
    Location:
    Anaheim, CA
    Since those heads are fully ported, they should be fine. I just know that #520 castings are a bit on the small side (I have some on a 283 in a '58 Chev 4x4). The rods should be good up to 5500, and 6 occasionally. Sleep well, I mean, how often are you gonna be up that high???

    ken
     
  7. JimmyDie6.2

    JimmyDie6.2 1/2 ton status

    Joined:
    Jun 20, 2000
    Posts:
    453
    Likes Received:
    0
    Location:
    Long Island
    Folks, isn't 96 octane in Europe like 87 octane over here in the states???? You should check that out because, with 13 to one you'll detonate a holes in your pistons really freakin quick. GOOD lUCK!
     
  8. Andreas

    Andreas 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    188
    Likes Received:
    0
    Location:
    Sweden
    No, no, no Jimmy, the comp is around 13 as of right now, and I´m going down to 10 - not building up to 13. Blowing my pistons up isn´t the main reason I´m going for 10, it´s because I would have to retard my timing so d*mn much I would loose too much power in low rpms.
    I don´t think your octane is different from our octane, it would only mess things up[​IMG]. Of course I could be wrong.
    What about the stud girdles I´m planning for the 406? Some ppl say it isn´t necessary for mild cams with lift below .500, and some say they wont build an engine without them.

    Andreas

    406cui of pure sh*t[​IMG]
     
  9. ken

    ken 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    1,244
    Likes Received:
    0
    Location:
    Anaheim, CA
    Stud girdles are unnecessary for under .500" lift, and especially since you won't be running over 5500 or so.

    ken
     
  10. Andreas

    Andreas 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    188
    Likes Received:
    0
    Location:
    Sweden
    Yeah, but I´ve read they prevent roller rocker "wandering". True or false?

    Andreas

    406cui of pure sh*t[​IMG]
     

Share This Page