02NBMFormula

iTrader: (6)

I got the bird back last week and im in the process of putting break-in miles on it, which sucks mightly. Vengeance did all the work and tuned it but didnt lean on it hard yet. It dynoed 480@7psi. with the stock motor it but down 470@8.5 psi. Here are the specs off the top of my head:
diamond pistons
arp studs
ls6 cam
ls2 heads
ls7 lifters
ported/shimmed oil pump
patriot dual springs
comp 7.400 pushrods
RPM stg V tranny
better timing chain

Comp ratio is 9.48:1

i got the old motor back to see if i could salvage anything and to see what the hell went wrong. here are the pics.






As you can see, broke a ring land off #7 and cracked the block

im planning on pumping the boost up to about 12 psi but im not too sure what i need to do fuel wise to support it partly b/c i dont know what it would make with that much boost. currently it just has 60lbs. and a walbro. any suggestions???

also, its really good to have the bird back after driving a suv for a couple months. thanks again vengeance

BlkHwk

iTrader: (8)

Looks alot like my #7 cept I had 2 cracks.

cablebandit

iTrader: (37)

detonation from being too lean prolly

LS1curious

Rings butted. You can see the drag mark all the way down the bore.

BlkHwk

iTrader: (8)

I figured that was from the crack.

Reject

iTrader: (24)

nice nice!! always love these kinds of pix

BlkHwk

iTrader: (8)

One nice thing about carnage.

Upgrades

Sideways240sx

iTrader: (22)

I would imaging 12 psi would put you somewhere in the 600's. The fuel pump would be near maxed out, and the injectors should be ok for a little more. if you do a racetronix hard wire kit, or a 2nd walbro you should be ok.


Congrats on getting her back.

Chris

Beaflag VonRathburg

iTrader: (176)

I'm glad to see you got it back together. What made you decide not to stick a set of forged rods in there? If you say cost I'm going to refer you to ebay where you can get a set for about $300 shipped.

02NBMFormula

iTrader: (6)

the rods are supposed to be good till 700 and dont plan to push it that hard, just something to have fun with.

i was kinda relieved when it popped, i knew it would happen sometime, just didnt know when.

Websy21

iTrader: (34)

My buddy did the smae thing when he rebuilt his 346, used stock rods and I don't know why. They say 700hp but like mentioned is it worth the risk to go through that again? Good luck on your setup and I've heard of a racetronix and a Bap pushing to about 600rwhp and maybe a bit more but than it will start to get hard on the pump too. At the price of those 2 parts you might as well do a home made dual intank walbro setup and be done. With the 60#'s you'd be more than sufficient for your needs. Plus more room in the future when the boost bug bites you, LOL

SStolen

iTrader: (22)

What kind of quality does $300 shipped buy you concerning those pistons??????

kp

iTrader: (34)

I would trust the stock rods over a set of 300.00 eBay rods

I ran stock rods with ARP bolts for quite a while with no problems, upside is they are pretty light. RPM would be my only concern and with the stock rodded/forged piston engine I kept it under 6700rpm. I ran 9.70s for a year with that engine and its still running 3 years later in a daily driven heads/cam M6 car.

I did the same thing on #7 with a 150 shot a while ago, very common, I leaned it out a little too much with the nitrous trying to get a tenth and paid the price..

Websy21

iTrader: (34)

You are right KP about the rpm's and I did forget to mention that my buddy is revving over 7000 with those rods which I wouldn't think of doing. H/C car with hope of spraying a 300 shot, good luck. He does have arp bolts but I don't think thats his concern. However like KP said, if spinning lower under 7000rpm would be a different story.

kp

iTrader: (34)

Quite a few head/cam guys are doing 7200+ on stock shortblocks. Myself I have never seen a stock rod fail, seen plenty of spun bearings and broken pistons that started it all. I'm sure some have just failed but they really are a pretty decent piece. When doing an engine you can easily take something that you could do for 1500 and spend 10,000 for the best parts to be safe, just depends on your goals and budget.

02NBMFormula

iTrader: (6)

im not planning on spinning it that hard, maybe 6500 max. ive learned my leason, it sucks to blow a motor.