I found the limits of a stock bottom ended Z06. My cylinder 7 has gave way under the pressure of 568rwhp and 482 rwtq. Going to buy a forged shortblock from Andy at A&A tomorrow. I know there have been some questions lately about "how much hp can a stock bottom ended ls6 handle". Just wanted to add my experience.
Jim
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'03 Torch Red Z06 462rwhp/408rwtq
Spdrcri,
Good luck on your new buildup. Now you'll have some new choices to make.
I'm running similar numbers to you, but she hasn't been hurt yet. I'd like to know what your driving habits have been leading up to your engine's demise. I'm planning doing the forged internal thing latter this year, but don't want to be rushed into it with a blow motor. Have you been easy or hard on her?
Spdrcri,
Good luck on your new buildup. Now you'll have some new choices to make.
I'm running similar numbers to you, but she hasn't been hurt yet. I'd like to know what your driving habits have been leading up to your engine's demise. I'm planning doing the forged internal thing latter this year, but don't want to be rushed into it with a blow motor. Have you been easy or hard on her?
I would drive pretty easy 85% of the time, not taking it over 3k rpms. I would have an occasional romp to 6700 rpms in a couple gears but thats about it. When I finally had blow by in the cylinder, I was running down a 350Z that flew past me and noticed the smoke pouring out the back of my car at 140 mph.
You mentioned I have some new choices to make. What would those be?
Im surprised with a h/c package your only making 570rwhp. Is that tune limited? Im hoping for 640-650rwhp and about 600 rwtq out of Andy's stage II h/c package and a 11-12lb pulley for the P1.
Some of the car mags claim to have an LS-1 limit set at about 650 with the aluminum block with the Iron block going well above that. They seem to think the block is the limiting factor in this case. Those limits were set using forged components. The NHRA Super Stock guys seem to be putting out some good power going the N/A route. Super Charging/NOS is another thing altogether. I know of one supercharged guy having things give up with just an over rev. Just looking at some of the numbers out their, the guys on this forum have reached that level or surpassed it already. The key to this whole thing is what are you going to be doing with your car. Sounds like a race only piece.
Some of the car mags claim to have an LS-1 limit set at about 650 with the aluminum block with the Iron block going well above that. They seem to think the block is the limiting factor in this case. Those limits were set using forged components. The NHRA Super Stock guys seem to be putting out some good power going the N/A route. Super Charging/NOS is another thing altogether. I know of one supercharged guy having things give up with just an over rev. Just looking at some of the numbers out their, the guys on this forum have reached that level or surpassed it already. The key to this whole thing is what are you going to be doing with your car. Sounds like a race only piece.
D.J.
But I didnt really ever "beat" on the motor. All of my "blasts" have been from a roll. I would say I got on it about twice or three times a week. I wouldn't say I abused the motor. I was running rich for about a month before this happened. I wonder if this might have something to do with it. I couldnt get ahold of my tuner to fix my program.
Either way.....I know 568rwhp is tempting the limits of a stock bottom end and knew I would have to go forged someday.
In my opinion, anyone who even does a h/c mod should not be surprised if the bottom end doesnt let go at some point. I have seen it countless times. People usually build from the top down, when they should be building from the bottom up.
Nutbush,
Well said and hind site is always best. For me, the problem was not understanding myself. I couldn't see what I wanted the end result to be, before I began modding. Now that I know what I want from the car, I'll go back and fix it. Question is do I wait for it to blow up, or make a preemptive strike and upgrade before I'm in spdrcri's position. I think the risk of additional damage mandates making the upgrade before she blows. In the mean time, conservative driving makes good
sense.
Nutbush,
Well said and hind site is always best. For me, the problem was not understanding myself. I couldn't see what I wanted the end result to be, before I began modding. Now that I know what I want from the car, I'll go back and fix it. Question is do I wait for it to blow up, or make a preemptive strike and upgrade before I'm in spdrcri's position. I think the risk of additional damage mandates making the upgrade before she blows. In the mean time, conservative driving makes good
sense.
Rod,
I would do the forging now, when you have a rebuildable block and can get back your core charge. Fortunately for me, I think I just had ring problems and the block is unhurt. I'll get my core charge back.
For the last 2 years I have been at 400 rwhp. I use my car for 10-12 track days a year, 4-5 auto cross events and some spirited street driving. I'm not a drag racer.
Last week the car was feeling pretty weak, oil presure was a little low. When I drained the oil there was a lot of metal and sludge. We removed the pan and things were looking even worse. I had the engine pulled and torn down and we found the #5 rod main cap was black and blue. The bearings were tore up and worn completely out of shape. I'm surprised this thing didn't seize up on the way to the shop. I'm NOT crying about it!! I got a lot of hard,VERY fun miles out of this engine. (20000)
I ordered a forged 348 CARTEK Stage 2X engine and CARTEK clutch. Everything should be here next week and we'll have this back on the road soon. I'll keep you posted.
Dave, Like you said it may have just been worn out given the miles you have and the amount of "spirited driving" you stated. Then again it may be a lubrication problem with the oil pump being the problem. At this point it's hard to tell. The good news is you didn't shell everything out the bottom at speed oiling down those rear tires. Consider yourself lucky. You can replace the short block but it's hard to replace BigD.
Don't know if your new short block has a blue printed oil pump or some other refined piece. Buy the best part you can find of course.
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Now you can add more boost to really go. 
Some of the car mags claim to have an LS-1 limit set at about 650 with the aluminum block with the Iron block going well above that. They seem to think the block is the limiting factor in this case. Those limits were set using forged components. The NHRA Super Stock guys seem to be putting out some good power going the N/A route. Super Charging/NOS is another thing altogether. I know of one supercharged guy having things give up with just an over rev. Just looking at some of the numbers out their, the guys on this forum have reached that level or surpassed it already. The key to this whole thing is what are you going to be doing with your car. Sounds like a race only piece.
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