Two! Two cracked pistons, ah ah ahhh.

[enkeivette]

Vette had too much blowby. Did a compression test, zero in the number 7 cylinder! So I pulled the head off and this is what I found.

http://i712.photobucket.com/albums/ww122/enkeivette/DSC02522.jpg

Oopsie Daisie. Guess 13lbs of boost is just too much on 91 octane! Regardless of how much timing I pull and how rich I tune it under boost. Time to order that intercooler and mandrel pipe kit!!! I'll clean off the melted aluminum tomorrow, and decide whether or not the cylinder is ok. If so, I'll just order another piston and throw it in there. Cylinder head was fine this time. If not, I might bore it 60 over and go with some low compression pistons. I really don't feel like pulling the motor though.


My Jeep is coming via semi-truck tonight or tomorrow. I've seriously been considering putting a junkyard 350 in the Vette with a 5 speed, selling it, buying a 1st gen Camaro caged and tubbed less drivetrain. And dropping the Procharged stroker in it with the 6 speed. It would be easy to tow it around, and I could turn up the boost, run race gas and actually get traction.

[enkeivette]

PS, Glenn or Ron, if you're out there. Does the dot on the ring face up towards the sky or down towards the ground? I forget.

[SeanPlunk]

Wow, that sucks. Buy a 1st gen Camaro and don't look back.

[SeanPlunk]

http://the-grayline.com/wp-content/uploads/2008/09/1969-camaro.jpg

:drool2::drool2::drool2:

[heypal]

PS, Glenn or Ron, if you're out there. Does the dot on the ring face up towards the sky or down towards the ground? I forget.

towards the sky bro

[enkeivette]

towards the sky bro

Thanks G money splooge fest. :beer:

[Vettezuki]

Ouch. :(

[Damian]

Keep the Vette, yours is one of my favorite body styles.

[94cobra69ss396]

Jerry's correct. What's your static compression? You can run 13psi you just have to pull a lot of timing out. I'm running 12psi but I only have 15 degrees total. The damage is caused by detonation. That's what the Cobra's stock pistons that broke from detonation looked like. Are you using a boost retard ignition box?

[enkeivette]

I've pulled 12 degrees total from stock. Intercooler is the answer. 9:1 comrpession. Recommended 9-10 lbs hot air. 19 intercooled.

13 intercooled should be a walk in the park.

[enkeivette]

PS. I think pulling timing can help with detonation, but detonation is basically dieseling isn't it? So at a certain point, it shouldn't matter how much timing you pull, or even if there is a spark at all. Or am I missing something?

[94cobra69ss396]

That means that you are still running about 22-24 degrees total which is too much to be be able to run 91. I'm also running 9:1 and at 17 degrees my car will ping above 5000rpms on 91. At 15 degrees I have no issues.

You need one of these. It will allow you to run more timing at lower boost levels and then pull timing as boost increases. It makes a huge difference in the low and mid range power. I wish I would have kept the one that came with my kit because I would have given it to you but I sold it years ago. I didn't need it because Steve controls it in my tune.

http://www.summitracing.com/parts/MSD-8762/

[94cobra69ss396]

PS. I think pulling timing can help with detonation, but detonation is basically dieseling isn't it? So at a certain point, it shouldn't matter how much timing you pull, or even if there is a spark at all. Or am I missing something?

Detonation is caused by the fuel igniting before the piston has reach TDC. The pinging sound you hear is from the air/fuel mixture igniting while the piston is still traveling up. The pre-ignition is trying to force the piston back down before it has reach TDC. This can be controlled by having the mixture ignited at a later time (less ignitial timing).

[big_G]

Vette had too much blowby. Did a compression test, zero in the number 7 cylinder! So I pulled the head off and this is what I found.

http://i712.photobucket.com/albums/ww122/enkeivette/DSC02522.jpg

Oopsie Daisie. Guess 13lbs of boost is just too much on 91 octane! Regardless of how much timing I pull and how rich I tune it under boost. Time to order that intercooler and mandrel pipe kit!!! I'll clean off the melted aluminum tomorrow, and decide whether or not the cylinder is ok. If so, I'll just order another piston and throw it in there. Cylinder head was fine this time. If not, I might bore it 60 over and go with some low compression pistons. I really don't feel like pulling the motor though.

Are those SRP pistons?...When I talked to SRP/JE, they said the SRP would not hold up under the boost I was planning, and that their JE blower piston would be much more durable. I am running 18-20 lbs boost (intercooled) at 32* with no retard. (8.3 scr and 92/93 octane). I did see some specks on the plugs after a hard dyno session, and have since switched to a colder plug. 11:1 afr also helps prevent detonation at the upper end (5,000-6,500 rpm).

[94cobra69ss396]

One more thing to add is you are not going to be able to just throw another piston in that block. Those scratches look bad.

[enkeivette]

Big G. Yes SRP, can a piston really crack just from too much boost? That would explain why I never hear detonation when this happens.

Ron, I know... but the wall looked bad last time too, and it was just streaked aluminum. Well see. If I clean it and my fingernail catches, I might pull it out to bore. Might get a new set of pistons too if the SRPs won't handle boost. They are forged though, strange. I don't see how one forging could be weaker than another.

[Ryridesmotox]

Have you tried running it on E85. There are guys running up to 30 degrees of advance on stock ecotec LSJ blocks with over 25 psi with a turbo. E85 is great for a boosted motor. It runs cooler, has an O2 molecule attached to it, takes longer to burn, is harder to burn, and allows for a ton of advance. With an intercooler and E85 you could probably run easily into the 20psi range.

[Ryridesmotox]

PS. I think pulling timing can help with detonation, but detonation is basically dieseling isn't it? So at a certain point, it shouldn't matter how much timing you pull, or even if there is a spark at all. Or am I missing something?

Diesel's use the injection of the fuel to initiate fuel combustion. The direct injection diesels can see like 30,000 psi, or some crazy shit like that, in the injectors. The extreme heat and violent injection makes the instant explosion and it sounds like knock but its not. The air is literally so darn hot and compressed that the diesel ignites. Diesel also burns EXTREMELY SLOW. The "detonation" sound in the diesel has more to do with the length of stroke and high cylinder pressure than actual pre-detonation. Pre-det will still destroy a diesel like anything else really. But since the fuel isn't injected until combustion is desired, there isn't much of an issue with pre-detonation really. I hope that makes sense.

[SkunkLookingCar]

Big G. Yes SRP, can a piston really crack just from too much boost? That would explain why I never hear detonation when this happens.

Ron, I know... but the wall looked bad last time too, and it was just streaked aluminum. Well see. If I clean it and my fingernail catches, I might pull it out to bore. Might get a new set of pistons too if the SRPs won't handle boost. They are forged though, strange. I don't see how one forging could be weaker than another.

It depends on the alloy used. Most SRP pistons are 4032 which is a higher silicon content aluminum that is strong and has good wear characteristics but is very brittle. Pistons forged from 2618 are generally considered a better choice for higher performance pistons since it is a much tougher alloy and doesn't allow crack propogation as easily as 4032. 2618 does wear more quickly than 4032.

[enkeivette]

No that's what I was thinking. Diesels create the explosion with the high cylinder pressure, and control timing by waiting to inject the fuel.

But with a gas engine, when the fuel is already in there, and the cylinder pressure is too high, it detonates or explodes from the high pressure, like a diesel would. At least that's how I was thinking.

Still don't quite understand how timing can prevent that, need to read what Ron wrote again.

[SeanPlunk]

Have you tried running it on E85. There are guys running up to 30 degrees of advance on stock ecotec LSJ blocks with over 25 psi with a turbo. E85 is great for a boosted motor. It runs cooler, has an O2 molecule attached to it, takes longer to burn, is harder to burn, and allows for a ton of advance. With an intercooler and E85 you could probably run easily into the 20psi range.

I've looked into doing it on the Cobra (700+rwhp with a Whipple 2.3), but their simply aren't enough stations in the area to do it.

[enkeivette]

Big G is right, I spoke with a guy over the phone at JE pistons. He told me that there are two different materials they use for forging, and with the better blower pistons they use a stronger material. Mine aren't.

So it looks like I might be going with a set of all new domed pistons. Or... might just replace the one and intercool. He said the intercooler might be enough to make them last. Might just get this thing running again for now and wait till I find a job to go crazy and do the first gen Camaro thing. Then do it right, bore out the block 60 over, new pistons, new head studs, new HGs, better clutch with my T56... in a 1st gen Camaro.

[enkeivette]

I like street gas, I want to be able to fill up wherever.

[enkeivette]

Also, the JE tech said my timing is already so LOW that it might cause problems. He said having it too retarded can also cause heat build up???

[enkeivette]

Skunk nailed it on the head, 2618 is where it's at for high boost.

[Ryridesmotox]

I hear you about the E85 being hard to find but it's worth it. And on my car its good for another 40hp at the wheels, for a V-8 car its even more. In regards to you timing questions, the reason that too much timing retard will cause excess heat is two fold... Ok one the combustion will continue while on the exhaust stroke of the motor. Two, that will translate to combustion going on inside the exhaust ports and headers. New engines have a "catalyst warmup cycle" that does this on purpose to heat up the cat quicker. My car would run at about 3/4 throttle with -10 degrees of timing... It sounded like the combustion was taking place at the turbo haha its so loud on a straight pipe.

Also, not to be a nag or anything, I would probably say get a whole new set of pistons instead of just two that you need to replace the broken ones. If it damaged two of them, chances are that the other ones have been weakened as well. Its totally your decision of course but I wouldn't want to put everything back together just to take it all apart again next month.

[94cobra69ss396]

I wouldn't pull more timing out thoughout the entire rpm range. You can run more timing in the lower range where you're not making as much boost. I'm not sure how much boost you have at 3000 but the Cobra only has about 3psi. With that boost retard that I link you could set it up to pull 1-3 degrees of timing per psi of boost. If you are making 13 psi and set it to 1 degree it would pull a total of 13 degrees.

So say you have the initial timing set to 14 degrees and you have another 20 in mechanical advance set to be in by 3000 rpms. If you are cruising at 3000 rpms with vacuum you'll have 34 degrees of timing. If you jump on the throttle and have say 3psi timing will be pulled back to 31 and so on. Once you are at 13psi you will have 21 degrees. This will help in both the lower and mid range power as well as help keep it from detonating.

Now this is in no way a replacement for an intercooler, I'd suggest getting one when you can afford it but it will help you run pump gas without one and is a lot cheaper.

On a side note what's with the dome piston? How much static compression do you plan to run? With your static compression of 9:1 and 13psi of boost your dynamic compression is around 16:1.

[Ryridesmotox]

^^^ Do this. Great idea, but as boost and heat build you might need to pull more than one degree per PSI, which is what he said in the beginning.

Enkei have you tried methanol injection to cool the charge down? It is initially cheaper than an intercooler and can add some power as well. It only comes on at certain throttle demand levels.

[94cobra69ss396]

The problem with running methanol injection is that you have to retune for it. Then if you run out during a full throttle run his pistons will look like they do now. I have a Mr Freeze system that I installed on the Cobra years ago but never tuned for. If you want to give it a try on the Vette you're more than welcome to it.

Here's a link to what it is http://www.andersonfordmotorsport.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=647&category_id=181&keyword=mr+freeze&option=com_virtuemart&Itemid=1

I also have 3 one gallon bottles of Snow Performance Boost Juice http://www.snowperformance.net/product.php?pk=3.

It's over at GTR for sale but if you want it let me know and I'll go pick it up.

[Ryridesmotox]

The problem with running methanol injection is that you have to retune for it. Then if you run out during a full throttle run his pistons will look like they do now.

This!!! Care must be taken while running meth. I guess I'm just used to tuning for everything. I have literally loaded 20 different tune files on my car for different stuff... Next will be an E-85/91 octane mix. He would need a tune for E85 as well.

I still highly recommend E-85, it is worth it. It literally is magic for a force induction motor. It's usually available at smaller stations that aren't linked to a mobil, shell, or chevron.

[94cobra69ss396]

This!!! Care must be taken while running meth. I guess I'm just used to tuning for everything. I have literally loaded 20 different tune files on my car for different stuff... Next will be an E-85/91 octane mix. He would need a tune for E85 as well.

He's running a blow through carb. The only thing that can be done is to add a sensor to the storage tank so that when the level is low it gives him a warning light.

[Ryridesmotox]

He isn't fuel injected? Haha oh gotcha... Ok well I got no solution for you then, its been a while since I tuned a carb. I will leave it to you guys then. If you need HP tuners ever let me know I got the software on my laptop.

[enkeivette]

I only blew up one piston this time, I said two pistons because I blew up another one last year.

You know what I just realized? Last time when I blew up a piston, another one got damaged. Just a few nicks on the top. Everyone said just file it down and run it, it will be fine. Well that was the one that blew this time. I think I'll be fine running the same pistons with an intercooler, that one just blew this time because it was already damaged. If I had replaced it too, I doubt it would have blown. 4032 it is.

[94cobra69ss396]

File what down, the piston? Do you have any pictures of what the original damage looked like?

[enkeivette]

http://i39.tinypic.com/2lld5w1.jpg

Glenn told me to! Bad Glenn... bad!

[enkeivette]

Those blemishes are right on the edge, and it looks like that's right where it broke. Gave the piston a starting point to crack.

[Shaolin Crane]

The problem with running methanol injection is that you have to retune for it. Then if you run out during a full throttle run his pistons will look like they do now. I have a Mr Freeze system that I installed on the Cobra years ago but never tuned for. If you want to give it a try on the Vette you're more than welcome to it.

Here's a link to what it is http://www.andersonfordmotorsport.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=647&category_id=181&keyword=mr+freeze&option=com_virtuemart&Itemid=1

I also have 3 one gallon bottles of Snow Performance Boost Juice http://www.snowperformance.net/product.php?pk=3.

It's over at GTR for sale but if you want it let me know and I'll go pick it up.

I'd like meth too, but diesel kits arent cheap, but windshield wiper fluid works very well as juice for it

[Ryridesmotox]

They aren't just for diesels anymore. Meth/water injection is great on forced induction motors. The only issue is like what cobra says... You don't want to run out. But there are built in gauges and such if you want them.

[Shaolin Crane]

They aren't just for diesels anymore. Meth/water injection is great on forced induction motors. The only issue is like what cobra says... You don't want to run out. But there are built in gauges and such if you want them.

When did i say they were? I said the diesel kits are more expensive than the gas kits so i'll have to hold off getting one for my diesel, run out on a diesel and its not too big a deal.

[enkeivette]

The don't use that chemical in windshield washer fluid in CA anymore, I'm pretty sure. And I'm not doing that. I'm going to intercool.

[94cobra69ss396]

You are correct, the windshield washer fluid we have here in CA doesn't contain methanol.

[Shaolin Crane]

The don't use that chemical in windshield washer fluid in CA anymore, I'm pretty sure. And I'm not doing that. I'm going to intercool.

They do in the concentrated form, we do jobs for granitize which makes car car products for a lot of big names along with their own stuff, so i have 6 or 7 cases of it that i plan on using.

[Ryridesmotox]

When did i say they were? I said the diesel kits are more expensive than the gas kits so i'll have to hold off getting one for my diesel, run out on a diesel and its not too big a deal.

Oh I thought you were saying to put a diesel kit on his car... I have one on my 6.5 liter and it helps with fuel economy and a little power cuz I can run more boost.

[Shaolin Crane]

Diesel not only benefits from lower temps but its also extra fuel for them as well, ive seen 100rwhp increases on standard meth kits with a 7.3l diesel

[Ryridesmotox]

Well the poor ol 6.5 Indirect Injection Detroit didn't get nearly that much power but it was a nice addition. I only use the stuff if I am towing something. Usually it's not much, just a trailer full of dirtbikes but it keeps things at a nice temperature. Very good addition.

[Shaolin Crane]

I plan to add it in the aid of the 50lbs i am running now, would clean up the unburnt fuel nicely, should put me in the 700rwhp/1300rwtq range

[Ryridesmotox]

Haha I think my old 6.5 is cranking out a whopping 400lbs/torque haha... The ol detroit never was a powerhouse. but I'm still on original injectors, original injector pump, and original glow plugs. Quite literally all I have done is change the oil... She's been a good truck to me. I'll probably cry myself to sleep when I get a Duramax next year.

[enkeivette]

Ok, if I bore this cylinder out say 60 over stock, can I run a 30 over piston?

My choices are right now:

Run it as is (the cylinder wall is slightly pitted).
Use one of those 3 stone cylinder wall grinders... eek.
Bore out just the one cylinder.
Buy a machined block for a couple hundred bucks are transfer everything over.
Or, let the car collect dust for a year till I have enough money to do it right. If I do this I might even sell the car and store the motor/ blower for a purpose drag Camaro.

[94cobra69ss396]

Ok, if I bore this cylinder out say 60 over stock, can I run a 30 over piston?

My choices are right now:

Run it as is (the cylinder wall is slightly pitted).
Use one of those 3 stone cylinder wall grinders... eek.
Bore out just the one cylinder.
Buy a machined block for a couple hundred bucks are transfer everything over.
Or, let the car collect dust for a year till I have enough money to do it right. If I do this I might even sell the car and store the motor/ blower for a purpose drag Camaro.

You can't use a .030 piston in a bore that is .060. The piston to wall clearance would be too much and it would destroy the piston. You could have the block checked to see if the scatches are too deep to hone out but my guess is that they are. If if was my engine I would just find another block that has already been machined .030 over.

[Damian]

If I were you, I'd just pick up a machined block and swap everything over. I don't see anything wrong with that at all.

[enkeivette]

Fuck! If this Camaro engine sale goes through I'll do that.

[enkeivette]

On second thought, I think I'm just going to button it up as is for now. I don't even have $200 to spare for another block. And I don't want to go through that entire engine, keeping those pistons and my NA cam. It's a waste of time. Just going to get it running for now till I get a job, then I'll do it right.

Then I'm going to swap an LT1 or something in the Vette, sell it. Replace the pistons and cam in this motor with a blower cam and blower pistons. And drop it and the T56 into a 1st gen camaro that has already been tubbed and caged.

[enkeivette]

Worst case scenario, I waste $50 on the new ring and intake gaskets, and some labor.

[enkeivette]

And then I can run these pistons on my boat motor with H&C and build a high compression beast out of that L48.

[enkeivette]

I think I'm going to try the cylinder hone. Might as well.

[Vettezuki]

And then I can run these pistons on my boat motor with H&C and build a high compression beast out of that L48.

One does not usually associate L48 and beast. :judge:

[enkeivette]

Change everything that breathes and sure...

I'm really going nuts on this one. I'm just at a new low right now financially. After paying those Jeep taxes I'm actually counting on money from that Camaro engine just for food and gas. The best solution IS to buy a new block, but that's even a stretch right now.

I keep going back to the idea of putting a different engine back in the vette with a 5 speed, selling it, and putting my powerplant to the side till I can do it right. Ben, how much would you want for your original vette engine, less crossfire?

[Vettezuki]

Change everything that breathes and sure...

I'm really going nuts on this one. I'm just at a new low right now financially. After paying those Jeep taxes I'm actually counting on money from that Camaro engine just for food and gas. The best solution IS to buy a new block, but that's even a stretch right now.

I keep going back to the idea of putting a different engine back in the vette with a 5 speed, selling it, and putting my powerplant to the side till I can do it right. Ben, how much would you want for your original vette engine, less crossfire?

I'd be happy with $400~ for the L83 + 700R4 (minus crossfire bits). Figure half of that is for the 700R4 easy. You're looking $200~ range. They're just a commodity item with nothing special.

[enkeivette]

Are you asking only $200 for the motor if I don't want the trans? Am I reading that right?

[Vettezuki]

Are you asking only $200 for the motor if I don't want the trans? Am I reading that right?

Maybe. Let me check the market. I don't need to put your balls in a vice, but I don't want to give it away either. It seems the pistons are forged stock.


<< The stock pistons are forged TRW-464664

[enkeivette]

http://i712.photobucket.com/albums/ww122/enkeivette/newpiston.jpg

[Shaolin Crane]

Shiny :)

[94cobra69ss396]

It's about time you got that thing running. Now do yourself a favor and pick up a boost retard ignition box.

[Kozak]

I just realized the title of this thread is supposed to be read in The Count's voice, of Sesame Street fame. Well played sir.

[enkeivette]

It's about time you got that thing running. Now do yourself a favor and pick up a boost retard ignition box.

I'll do you one better... intercooler. I can run 19lbs intercooled according to ATI, so 13 should be fine. I can probably even bring the timing back up. Although, I might not till I get a job!!! :uh::smack:

[enkeivette]

I just realized the title of this thread is supposed to be read in The Count's voice, of Sesame Street fame. Well played sir.

:bigthumbsup:

[mdpalmer]

Man that blows, that's a sweet vette you got there. 1st gen camaro sounds delicious too, however :) Good luck, I know how tough the money situation can be when you have a car hobby.

[BRUTAL64]

Good thread!


Now you guys know what I think about first gen Camaros.


They look great---- drive like a ...... Nova.:lmfao:


The good thing is that they can be updated to REALLY good front suspension.

[Damian]

I'll do you one better... intercooler. I can run 19lbs intercooled according to ATI, so 13 should be fine. I can probably even bring the timing back up. Although, I might not till I get a job!!! :uh::smack:

13?!?! I wasn't making much power until I got up into the 20s. I actually started knocking around 18-19, but cleared up at 22, which is where the motor felt much smoother. Sad for me though is that you'll make more power than me!

[enkeivette]

13?!?! I wasn't making much power until I got up into the 20s. I actually started knocking around 18-19, but cleared up at 22, which is where the motor felt much smoother. Sad for me though is that you'll make more power than me!

13lbs of boost in a 6.3L engine is a lot more air than 13lbs in a V6. I think at 22lbs of boost I would be close to quadruple horsepower territory. Haha, but my engine isn't built for that. Mine was built for about 800hp max. If I have to take it apart again I'll build it better though, and I'll up the boost for sure.

[Damian]

That's true. Ever think of running meth injection?

[jedhead]

My car has 13lbs of boost from the factory.

Bob

[BRUTAL64]

My car has 13lbs of boost from the factory.

Bob

My car has "0" boost from the factory:nutkick:

[ZexGX]

http://i712.photobucket.com/albums/ww122/enkeivette/newpiston.jpg

I take this and raise you!
:whistle:
http://img204.imageshack.us/img204/9007/forgedls1shortblock.jpg

[enkeivette]

Raising me with a NA LS1? That's not even a call bro. :nutkick:

[enkeivette]

Say no to meth, 91 all the way!

[ZexGX]

Raising me with a NA LS1? That's not even a call bro. :nutkick:
It was more about the dished and coated pistons that you should be running, although the fact that it's an LS1 isn't too bad either. :)