400 C.I. Vortec

[Mississippi]

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[FastOrange]

Why would you? 400 isnt a really great motor by any means, the money you have into this you could build a nice 383.

 

[Mississippi]

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[FastOrange]

I like the long stroke of the 400. Iike low to mid range torque. Spinning a motor over 6k with ps, alt, etc is hard on those parts. Let alone the tranny. I'm just weighing my options really.

383 has the same stroke...

 

[Mississippi]

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[sewlow]

http://www.jalopyjournal.com/forum/showthread.php?t=5078

 

[Mississippi]

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[Mississippi]

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[Mississippi]

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[michael hurd]

Has anyone successfully merged a 400 sbc to the 5.7 vortec head? I found a thread on another forum on a basic parts list to do so:


i need to drill steam holes in my heads.

use a vortec balancer

vortec timing cover

and a retro-fit hyd. roller setup.

did i miss anything?

He never did respond on how the build went. Does anyone have info on this. I have my eyes on an non bored 400 block that I want to sweep up and slowly build to be a NA power house

You need to drill steam holes, and use the correct gaskets. The 400 balancer is externally balanced, the vortec one is not, if you use the wrong balancer, it will result in an imbalance condition. A vortec timing cover will be needed. You also have to use a vortec distributor, since the wrong gear will cause rapid wear issues.

Yes, you could use a retro-fit hydraulic roller set up, but it will be much more expensive since you need lifters with link bars, rather than re-using a factory set of lifters, the valley spider and dog bones. Pushrods you will have to measure, you will need to buy an adjustable one, and check the geometry. Figure 2 weeks from the time the order is placed to get pushrods.


Personally, I wouldn't take a 400 block at all. Cheap castings, with low nickel percentages mean they wear very quickly. ( any older SBC / BBC / Pontiac / Olds / Cadillac / Buick engine has these issues though )

In stock form, they were a bit of a . Short connecting rods with a piss poor rod to stroke ratio, ( 5.565" vs. 5.700" ) soft iron blocks, and so-so compression ratio.

I would much rather clearance a vortec block, and install a long stroke crankshaft as part of a complete balanced rotating assembly. You can get a complete assembly with 6" connecting rods, 6.125" etc. These rods are profiled to give you more camshaft base circle clearance, so you do not have to run a small base circle camshaft, as you would if you used a stroker crankshaft with a stock or generic aftermarket rod.

The companies have already done their homework, and it's a no-brainer for any competent shop to machine a block to the required bore size ( you can get kits in 0.10, 0.20, 0.30, 0.40" overbore etc ) and grind a bit of material off of the pan rails.