If I was building a 408 on a budget, I'd get a Eagle 4" crank for $850, bore it .030" over and use factory o/s pistons for $250, maybe a $250 lingenfelter cam... Reuse the stock rods with good bolts, rebuild the stock heads, and I suspect you could finish the project, machining and all, for under $3000 if you assemble it yourself.

...now, if money was no issue, I'd get a 4.25" Callies crank....

 

You couldn't use a stock replacement style piston and factory rod with a stroker crank, because the added length of the stroke will push the piston too far out of the hole. You need a stroker piston with a reduced comppression height, or a shorter rod, which is never a good idea.

 

I tried the budget 408 build. It took me 4 months or so to get parts together. I picked up a eagle fordged rotating assembly with diamond pistons for about $2500 or so with comp lifters and 42lb injectors and bearrings. I used a rough 6.0 block so some machine work needed to be done. since they had to check everything for clearances i let the machine shop assemble the short block. The total cost from the machine shop was $450 and that includes a little extra for getting it done quicker. I sprung for ARP bolts, $650 or so. Stroker cam, not nessary but I found a used/new one for $300. I used all new gm gaskets and that was around $200. As for heads you can get by with stock 317 heads with springs and running a small cam but if you go with a larger cam the heads would at least needed to be p&p for it to breath good.
Right now I am in the $5000 range for my 408 and it will keep getting higher. That figure dont include the tranny parts that I have.

I wanted to keep my build in the $3000 range but I figured I might as well spring for the best parts because i dont want to have to repair the engine if something i cut a corner on broke.

Next thing is since your truck now has 150k miles on it what are you going to do about a tranny?
hope that helps some

 

Im not postitive on the 402 thing it would be worth researching.

 

my bad... so you spend $500 for a set of forged aftermarket pistons instead of $250. You can still keep it under $3k if you're conservative, which none of the posters have been thus far.

 

T-Byrne (sponsor) sells a 402 (high and low compression) package that includes:

(Low Compression, which is what I'm interested in with a turbo)
4.000" 4340 forged steel crankshaft, balanced to rotating assembly
4.000" heavy-duty, low-compression, 2618 forged alloy pistons (includes new rings and full-float pin)
6.125" H-beam rods
402-CID displacement
9:1 compression ratio (nominal; ultimate compression ratio will depend upon heads and gaskets used)
Designed for forced-induction applications
Includes new rod and crank main bearings

for $2,470. Is this a good price for all of this if you plan on installing it all yourself? What's missing?

It doesn't look like any bore is necessary to achieve 402ci out of a 6.0 bottom end. Hmmm...

 

About the tranny, my uncle totaled out his 00 2500 with 24k miles on it and he gave me the tranny, so I am good to go there.

Like I said I will be doing most of the machining and ALL of the disassembly and assembly myself so that will save quite a bit of money. The Eagle crank sounds like that should be the best buy. As for pistons I will be talking to the local big engine builder and see what he says and if he has any hookups.

Sorry for the late and short reply, I am very busy with work I will try get back on here with more info soon.

Mike

 

This is what I was originally planning, but my buddy who is helping me install the new motor and tranny said that the LS2 has different knock sensor position and wasnt sure how much difference it would be. So I guess Im going to go with a 408 as well and was considering HPE.
Steve, let me know how they treat you and how everything goes. If all is well, I'll order my shortblock the day youve got yours in and running.... Ive heard too many horror stories about new motors. Otherwise I may go with Futral

 

Id much rather put the money from boring the cylinders towards head work even just a good 5 angle job and removing castings on some ls6 heads or lq9 is worth at least 30 more flywheel ponies plus a bigger cam is gonna be happier. All Ive had done to my heads is 5 angle job, larger valves and unshrouding I think it has helped alot especially in the torque area.

Id think a 402 with headwork would outperform a 408 with no headwork especially if any cam over a stock one is involved.

 

Even if the 408 has had similar headwork done, will 6ci really make that big of a difference? What are we talking about, 5 - 10 more hp/tq as a result of the extra cubes?

I'm just trying to make a good decision here and am trying to understand the pros/cons of going either route. If I'm not going to gain much by boring the block out to a 408, then I'd rather put that money towards a turbo or nitrous set-up instead.

Thanks all.