Fb0dy0nly

iTrader: (10)

Another way to keep the rears cold is to buy two front ls6 coolant lines and then run a hose to connect the two around the side of the intake which then would T into the coolant line running to the radiator. This way you can run any intake without having to hack it up underneath and still get coolant to the rears.

Good luck with the new build!

The Alchemist

iTrader: (19)

Well, I'm leaning more and more towards just doing a cleanup and rods/pistons. The car honestly was as fast as it needed to be for me because it's 100% a street car, and at this power level, I'm not hooking at all.

I'm going to have to do some extensive reading here because I've never thought about building a shortblock myself. I know there are some pitfalls with getting things done right or else the motor won't last. Hopefully I can get some guidance from some local members and of a good machine shop to do the block prep and engine assembly.

Removing and reinstalling the engine should be straight forward. It's the critical things like setting ring gap, and bearing clearance and balancing that worry me.

Bob@BruteSpeed

iTrader: (16)

Make sure the #7 cylinder wall is not cracked, which can happen if you drive the car after the ringland has cracked, and a broken off piston piece gets wedged between the piston and the cylinder wall. I have seen this happen several times.

When looking for a machine shop look for one that uses torque plates for honing LS engines, skip over the ones that don't have the plates.

Don't order the pistons until the machine shop verifies that a .05 hone will do the job, unless you know for sure there are no deep scratches.

Between the rods, pistons, file to fit rings, machine shop cost, oil pump, timing chain assembly if not reasonably new, head studs, bearings, gaskets, fluids, etc, the cost adds up quickly. You can have 3k in it real easily. Hang in there! Bob

The Alchemist

iTrader: (19)

Thanks Bob. I haven't made any decisions yet with how I'm going to move forward. Not knowing anything other than something hit the spark plug, I can't say what I'm going to do. Hell, I don't know how I'm going to pull the motor yet. All in due time I'll figure it out.

stealth355tpi

Oh boy, just what I wanted to see. That sucks that it went already, I hope mine lasts longer then that. At least it happened during winter so you can take your time with a new short block. Good luck Brien

Louis

iTrader: (7)

What was IDC at 6800?
Ambient temp?
Boost was 14-15ish?
Meth?
Injectors?

I think it's heat related. A 4th gear pull is 150+ mph.
Pump fuel+150 mph+15 psi+10.7CR+stock pistons/ring gap= too much heat, and pulled the land off.

Louis

iTrader: (7)

Also, who ever said that the fast/common plenum didn't contribute to the problem is on crack. The LS style manifold has ALWAYS has lean #7 issues. The LS6 will be no different.

I do agree, steam tubes would help the cause.

The Alchemist

iTrader: (19)

The 4th gear pull wasn't that much... it was at 65-100mph, so the motor was only turning like 4500rpm.

I'm sure it was heat related. Trust me, I'm not here wondering how this happened. Ambient temp was 29-31 degrees yesterday. IAT's were in the 30-35 degree range. I'm running 60lb mototron injectors.

allout06

iTrader: (11)

sucks dude, good luck. keep us posted. im already thinking about how im going to forge mine, cuz i know its gonna happen. i have a more aggressive tune than yours too, granted your running 2.5 times more psi than me lol.. 11.5afr/18* timing @ 5.5psi here.. rev limiter set at 6500.

Let us know what way your going with the shortblock, i also am thinking about just forging my block and have the the stock crank cleaned up.. prolly diamond pistons/callies rods ect.. the "norm"

The Alchemist

iTrader: (19)

So do any of the vendors on here offer a forged 347 option using stock block and crank?

Tally TransAm

iTrader: (17)

shitty man, I might be in the same boat as you. a couple weeks ago the car tossed a belt at 6k+ rpms in 4th and got to about 255 degrees before I could shut down. havent touched it yet but not sure what im going to find when i do.

my plan to get out cheap is getting a shortblock built with my stock block and crank or a 5.3L iron donor. should be able to get a setup to handle 800+ rwhp for a good price and turn up the boost.

im interested to see what it looks like when you pull it apart

allout06

iTrader: (11)

if i remember right, i think ive spoke with texas speed before about this,and they said if you send them your block, they will machine and assemble it like they do with their short blocks. might wanna give em a call.

WS6sleeper

iTrader: (1)

So is this boiling down to a tune issue? Everyone saying heat caused it, not the weakness of the bottom end. If you had a forged assembly in there when this happened, do you think it would've been the same result? Thanks

The Alchemist

iTrader: (19)

If I understand correctly, I think it has more to do with ring gap, and the fragile nature of the stock pistons and their ring lands. Lost of people with NA motors lose #7 pistons. It might be a case of the back piston got too hot because I have the rear steam vents blocked using the ls6 setup with my FAST intake. My tune was quite conservative, but to be honest, I was probably making upwards of 650+ horsepower if not more. Fact is, I might have more damage than just one piston.

I have read that the ring gap on a stock ls1 is too tight, and when pushed, it actually closes up and binds in the cylinder bore, and then causes the ring land to crack.

Could I have saved this by running methanol/water to help cool the pistons, maybe, not sure. What's done is done.

Louis

iTrader: (7)

No, because you alter the way you build an NA engine that makes 300 hp vs a unnaturally aspirated engine that makes 700 hp.

Thats correct.

Although there are many many factors that come into play when putting an engine together, some of the most basic clearances are ring gap and piston to wall clearance.

tripblackls1

iTrader: (11)

If your even considering a non forged rebuild , then your best bet would be to pick up a jy 5.3 they handle boost better then ls1s and if your concerned about weight you can find them in aluminum block as well and either way its Going to be cheaper then a stock rebuild

allout06

iTrader: (11)

if it were me, and i was gonna to spend the time swapping a motor. might as well spend the money and do it right. instead of substituting with a $500 engine thats probably going to grenade also sometime down the road.

The Alchemist

iTrader: (19)

I'm still thinking and listening. Right now I'm just enjoying the Giants victory over the Packers.

allout06

iTrader: (11)

i say at a minimum, forged rods/pistons. and add a meth kit this time lol

WS6HUMMER

iTrader: (19)

Never considered the aluminum 5.3L, I'm very weight conscious. What advantages do the 5.3's have over LS1's, thicker sleeves?