400 SBC Build - Tight Budget

[GO-N-BRK_84]

Engine is mostly torn down, left crank, pistons and cam in. Not sure how much of this stuff the shop might want to see? I’ve attached a few pics, not sure if it helps. Cylinders are smooth with maybe a light swirl or crosshatch. Top of each cylinder has an easily removed carbon build up, but no lip or overhang.

 

[Ricko1966]

At this point I'm torn,because I can do this my self,butI think at this stage you should probably take it to the machine shop as is. Let them determine how much to deck it have them check the cc's in the piston, I want to know the cc's in the pistons and where the pistons are going to park so we can figure what cc the heads need to be to live on pump gas.

 

[GO-N-BRK_84]

At this point I'm torn,because I can do this my self,butI think at this stage you should probably take it to the machine shop as is. Let them determine how much to deck it have them check the cc's in the piston, I want to know the cc's in the pistons and where the pistons are going to park so we can figure what cc the heads need to be to live on pump gas.

Sounds like a solid next step, I’ll drop this thing on a pallet as-is and run it to the machine shop this Friday. I’ll report back any useful information.

Thanks for the help guys, I really appreciate it!

 

[Mark Jones]

First step here is to mag the steam holes for cracks, you have rebuilder special here, so it needs decked and honed to .040 with TQ plate. Line hone next.

 

[GO-N-BRK_84]

** UPDATE**

Local shop is backed up a bit, so my engine is scheduled for hot tank and mag late next month. Good news is it only costs $50, so I'll know if she's worth building without having to drop to much cash on it. I was quoted $1600 for a small block rebuild which includes machine work, new crank, rods and pistons...though performance parts will be a bit...extra. I'll keep ya'll updated! Thanks again!

 

[Catbox]

Might want to ask them to sonic check the bores while they are looking it over.

What is a sonic check on an engine?

Sonic checking is a method for measuring material thickness when you only have access to one side of the part. For instance, if you want to know how thick a cylinder wall in an engine will be, you would have to cut a hole in the wall in order to use a pair of calipers.

Here is a good read about it:

The Value and Benefit of Sonic Testing - Engine Builder Magazine

Sonic testing is probably one of the most valuable tools of engine building – and often the most overlooked. It allows the engine builder to gain a basic perspective of the integrity of the parts that are going to be used for the engine build.

www.enginebuildermag.com

 

[dbryan23]

Been seeing people destroking these lately. Dropping in a 327 or 350 crank, dropping displacement to around 354 c.i.
Making crazy power.

Is that basically just the same school of thought as what Chevy did with the 302 in the Z/28? Bigger bore with a shorter stroke to get higher revs and HP?

 

[Big Ray]

I believe so.
I want to build a destroked 350, I have a modified TPI unit I've been collecting parts for since '94. Should do a bit better than the 4500 rpm a 350 tpi chokes out at.

 

[68post]

Destroking an engine is a step backwards, unless it is to reach a cubic inch limit for class racing. Potentially less HP, or maybe the same HP - but at a higher rpm, but always with less TQ.
302 ci loses to a 327, and the same comparing a 327 to a 350, or 350 to a 400.

OP, good choice on the 400 build.

 

[idahovette]

Do NOT agree with your "theory" about smaller displacements losing to bigger engines. A lot depends on the build, the trans, the gears and how good you are at driving it!!!!

 

[68post]

"Theory"..LOL, Okay !

 

[SquareRoot]

Destroking an engine is a step backwards, unless it is to reach a cubic inch limit for class racing. Potentially less HP, or maybe the same HP - but at a higher rpm, but always with less TQ.
302 ci loses to a 327, and the same comparing a 327 to a 350, or 350 to a 400.

OP, good choice on the 400 build.

NOT. Too many variables. Every manufacturer is essentially "destroking and/or deboring" engines to achieve a smaller displacement. Then they throw a turbo on it and it blows the doors off yesterdays NA V8's. Just one example.

 

[68post]

NOT. Too many variables. Every manufacturer is essentially "destroking and/or deboring" engines to achieve a smaller displacement. Then they throw a turbo on it and it blows the doors off yesterdays NA V8's. Just one example.

Don't be argumentative just for the sake of it.
Yes, you can install a 4 cyl with a turbo and make more power than a stock smogger 454, but that obviously is not my point.
EVERYONE can see the point made, destroking your 400 will not instantly make it a high revving powerhouse that blows away all larger engine combos built within a 400 block. Build a 421 to race that 348.

I used to hear this BS in high school nearly 50 yrs ago, about how great all of their 327's are compared to all else. Raced 3 chevelles with 327's with my chevelle 350 and beat ea one, and only one was close. 2 - 4 speeds against my auto, but the powerglide car was closest and he had an extra 1.25 of compression (10.25-1) to my 9.0-1 compression, (and that may have been from a roll).

Unnecessarily making engines smaller doesn't magically increase their output, and no - I'm not considering you using a turbo on your 302 to keep up with my 407, let's be realistic .
Apples to apples, not apples to oranges !

 

[SquareRoot]

My stock 283 Chevelle would blow the doors off my buddy's 307 Camaro 100% of the time. Just sayin

 

[dbryan23]

Chevy designed the 302 specifically to be able to handle higher RPMs for longer periods of time (smaller crank, less rotating mass, less stress) and fit within the 305c.i. limit for the Trans Am series. It was just a 327 with a 283 crank. So yeah, if they didn't have a c.i. limit they would have used more displacement. But... engines with shorter strokes are generally going to rev more quickly and hit higher RPMs, thereby being more "sporty" feeling. Not good for straight-line drag racing necessarily, but great for road racing with lots of quick speed/RPM changes. And good for street-driven sports cars and sport trucks. For a 4x4 like the 400 SBC K10 I just bought, I want to stick with the bigger cubes and longer stroke since I'm more interested in low-RPM torque than high revs. I'll be spending a large percentage of my time going 35 mph or less on dirt and gravel roads in the North Georgia hills and mountains.