I scored a big block 402 with a 400 transmission and i'm planning on swaping my 355, it's a 2 bolt main, cast crank truck rods and cast pistons, everything looks great on it 4.155 bore(408) crank turned .010, only a few thousand miles on rebuilt, I want to build a single turbo setup is it worth to forge the bottom end on a 2 bolt main bog block?

 

You can always go with splayed main caps, or if OE block just girdle it for increased strength...

You going carbed with it or fuel injected?

- Rob

 

Not sure yet, it came with a Mighty Demon 750 in very good shape so I might just modify that for blow through, basically I bought a used carburetor and came with an engine and transmission attached, that's how cheap it was, and there's not a oil leak anywhere on the engine or transmission.
I want to minimize machine work, not cause of budget but because i'm one of those guys that "if I can't do it myself it's not getting done".
Already ordered main studs, head studs, aluminum heads, hydraulic roller cam and roller lifters, ss roller rockers, Victor Jr intake, and a few more stuff, I think it should be ok for 600hp with the mains studded and the cast crank, just get forged rods and pistons but i'm not familiar with big blocks, it's my first one.

 

Oh you're going to love the torque, it is instant. I wouldn't even shoot for horsepower, though you're going to have plenty of it anyway, I would just run it with the turbo under 5500-RPM, as it's going to pull you so hard you're going to resemble Chase and Akroyd from Spies Like Us in their g-force scene...

If I can help in any way don't hesitate, you're not that far from me...

- Rob

 

Thanks Rob I'll keep that in mind.

 

Ok I got everything I need to build this chunk of iron, including an OEM forged crank that I got on Ebay as a core and ended up being in excellent condition, the only thing missing are the pistons and rods, still debating on the compression ratio, so far I got the choice of 8.7:1 and 9:1 if I go forced induction or 10.6:1 and 10.8:1 for naturally aspirated, I doubt it will ever see a drag strip there's barely enough room for the big block as it is and all the custom work involved in the turbos and all the pipes, transmission, rear end....I wonder if it's worth it...decisions decisions decisions

 

A little mockup today to take some measurements, from the center of the motor mounts the height is the same as my small block, 1.5" wider on each side on the top corner of the heads, is 1" longer to the back, in the front that;s where the problem is, it's 4" longer, I can gain 2" with a short water pump but still going to be tight against my 3 row aluminum radiator and the Thunderbird electric fan, I might have to cut the top rad support to straighten it up and it will clear.

 

Some progress this weekend, got the new Derale dual fan shroud mounted, very powerful fans, a bit tight but with some trimming they fit, working on the adjustable controller today, it gives me 2" clearance with the long water pump...nice.
Also go raid of the ugly coolant ans W.W. fluid tanks and installed the 2 little guys on the picture, i love it

 

More updates, the cam i had and planned on using doesn't work for me, way too much overlap (100*??? i don't know what i was thinking ) i got a nice one from Howards taking my SCR of 10.69 to a DCR of 8.29, should work good on 93 octane and have a nice "dumpty dump.."
Howards #120405-8
Engine: 396-454/502 BBC
Camshaft Type: Hydraulic Roller
RPM Range: 2600-6400
Intake Valve Lift: .618"
Exhaust Valve Lift: .618"
Advertised Intake Duration: 288°
Advertised Exhaust Duration: 294°
Intake Duration @ .050": 235°
Exhaust Duration @ .050": 241°
Lobe Separation: 108°
Intake Centerline: 104°
So after the cam fiasco comes the rocker studs and push rods fiasco, stock studs are 1/2" too short and stock length push rods are way too long for the roller rockers, they would work for the stock stamped steel ones though, i need 7.900 on intake and 8.650 on exhaust, Summit Racing said they can help with some Trick Flow stuff for $180
On the car itself i removed the AC/blower box to replace with a non AC one, cleaned up some unused wires, now just got to wait for the shorter blower wheel and a new resistor controller from Rock Auto...They are pretty fast on shipping stuff but i hate waiting.

 

That's not gonna work

Starting to look more like an engine
If you look at the roller rocker i was testing with a small block push rod and it is just a tad short on the intake side, in a bind i would use it.

 

Finally got all the correct parts for the valve train, got a great deal on the titanium retainers, saved 11 grams over the chromoly steel ones.
Replaced the AC with a no AC box, mounted the coil and ignition controller, cleaned some more wiring, i'm not crazy about the blue wire loom
Now the project is going to be on hold for 3 weeks, i'm going on Vacation to Europe

 

Looking for some serpentine pulley kit for it, not crazy about the V belt

 

P




Pain in tha butt that no AC box