Ok so I know ive asked about this block on here before and after looking around my local junkyards for a 6.0 block I havent had any luck so I just wanted to revist this block and how it comes .030" over i would love to make 1000hp with my build but realisticly would be happy with around 700 I plan on using a callies crank and rods with diamond pistons I just wanted a few opinions on the block already being machined without the pistion if it would be reliable at that power the car is a street car with a few track days here and there

Thanks for the info,
Jesse

 

She be fine. Run it.
Its a good deal, youll have close to that into a JY motor anyways. Plus Machine work ($500 bore and hone with plates and deck), just have to check bores for taper.
for youre build the internals are junk anyways.
Sounds like a fun toy

 

What do you mean why are the internals junk? Is there somthing that would work better ? Im looking to make about 18psi

 

Im kinda new to the ls engine so just looking to get a little info on the good parts

 

I think he was referring to the stock parts if you built a JY engine.

 

Oh ha that makes more sense

 

Save your money and run a polished stock crank

 

Disregard just realized this was a 408

 

I wouldn't buy a pre machined engine. Still going to have to have it balanced and if the bore size isn't proper then you will have to machine it again to get proper clearance. Also if there is something wrong with it no way to have any sort of warranty against defects.

 

i would not do a 408 stroker for a street car. 4" stroker pistons have very short skirts, and the bores in that block are not long enough and the pistons rock in the bores at bdc and wear pretty bad. stick with a stock stroke or no more than a 3.8xx stroke crank with that block.

 

The "408" block is just a Iron 6.0L block bored .30" over. You do not have to make a 408 out of it, you can do a stock crank and make a 370.

 

408 stroker I'd run a forged crank. 370 I'd run a polished stocker.. Defyant is right, you have two options. I'd go with the 370

 

My 408 stroker is 12yrs old with around 35 to 40k miles and still running strong.I do agree running a 370 or 390 would be better for boost.

 

do you get just the block from Summit? if you get a junkyard engine, you have all the end plates, etc, that you have to find for a bare block
if I have a virgin block, I try and only go .005 and save it for an additional bore if needed later-sup once their bored to .030, there isn't much room to go beyond that, but I guess a sonic test would show how much

 

i dont plan on driving the car every day more of a weekend street car and some car shows so the street manners of the car are not a concern but the reliability of it is i go to a lot of out of state car shows so and the car will not be a trailer queen so it has to be able to make the drives and take a little beating on the way i mean whats the point of having all the power if your not going to use it right ha
and with the internals how much boost would you guys say is safe with like a 9:1 compression ratio and 93octane with meth? i know the tune has alot to do with it but im just looking for a good starting point

thanks for all the help so far
Jesse

 

+1..

Proper machine work and clearances will do way more for your oil control then the length of the stroke or length of the skirts.

My 402 takes 22 psi of boost and never uses even a drop of oil. I change the oil every 2k miles and it's always right where I left it when I filled it up.

Thousands of 402-408 motors out there running fine and not slapping pistons or using oil.. Don't believe everything you read.

I agree on the comment about machining your own block locally. If you buy a premachined block, you still have to size the bores to the pistons..at a minimum you'll pay for a finish hone/sizing locally.. Unless you just throw pistons in and hope for the best...--many people do this with some success.

 

We got plenty of boosted 408's running around on the street out of our shop in Colorado. Thing makes 700+ wheel and it gets driven everyday rain or shine. No problems with it what so ever. As long as you have a good engine builder there should be no problem.

Have you looked at ATK short blocks? You can buy what you want from them ready for whatever you want your set up to be. They also come with warranties. Id look into them as well.

 

Ill have to take a look at them but I was more looking to build it myself but its nice to know there are one out there that are making that power daily driven

 

I agree fully. My buddy had a SDPC 402 short block. Ran it HARD with some thin oil and didn't burn any at all. Motor never skipped a beat.

I also agree in that your machine shop will want to hone the bores to the pistons. Most do. What happens if the finished bore is a little too loose for your chosen pistons?

If the block was STD hone, 0.005 or even 0.010 over..... then maybe finish it to your spec.

 

Sounds like you are very new to the Ls motors. if your looking to build your first ls, on your own. My advice is to start out w a 4.8 or 5.3 and rebuild it. Very common and reasonable prices. If anything happens to it. You wont be out much and will learn from your mistakes and success. Stroker. Your looking at a minimum of 1800-2000$ for a quality rotating assembly.not including machine work. Thats just crank,rods,pistons,rings,bearings,rods