Please GM...upgrade the pistons in the LSA

[GM4lyfe]

Originally Posted by BoostedSS

The LSA is FAR from inferior, its a better engine in all aspects except for the pistons. You want proof, its simple... Buy one, put to much total timing into it and watch it grenade itself from detonation. Detonation is what kills those pistons, forged pistons will take a BEATING before they give, those hyper pistons will not. Say you have nothing more then a smaller blower pulley and an agressive tune. One bad tank of gas and or a really hot day and that is the end of that engine. Hell you dont even need a smaller pulley, just an agressive tune.

Even with the near bulletproof bottom end in my 408 I run methanol as a saftey factor. My tune is agressive and although forged pistons will take a HELL of a beating, no reason to risk it. But from first hand experience. Ive blown a hole in a Stock LS6 piston and Ive cracked a ring land on a stock LS1 piston. They break very easily....

There should be no reason why you would tune a FI motor to the limit. A good tuner would tune the car safe and would not have it on the edge of distruction with a bad tank of gas. If you have a tuner like that he/she is not a good one. That is plain dumb. There is no piston out there that can survive detonation and or running lean not even forged pistons, I know because I seen it for myself. I had to replace forged pistons in a FI car that had a bad tune. A good tune will go along way, thats all that matters. I'm good friends with a tuner and learned alot about tuning. Yes Hyper Pistons do have a limit, and I'm not saying that they are better than forged pistons. Most people don't need to get wound up about hyper pistons because most will never take it to that limit.

[BoostedSS]

Originally Posted by Dragoneye

If all it'll take is a bad tank of gas, or a hot day...I very much doubt they would have chosen them.

Factory tunes are VERY liberal, your never going to have a problem like that on a STOCK setup. This is also why GM has lojacked the ECU's to track the CVN numbers. That way when you bring your car in for warranty, if the CVN history does not match factory GM programming they will void your powertrain warranty. In stock form, there reliable as hell. But as I said, with an agressive tune, it wont take much for the engine to bite the dust.

Im done with the piston topic, ill let it be at this point as my oppinion is not shared.

[GM4lyfe]

Originally Posted by BoostedSS

Once again my point is that using forged pistons in a mass produced engine would hardly effect the price of the vehicle. Substituting forged for cast at that point in the vehicle/engine assembly is a matter of a couple hundred dollars at MOST and I think thats even being generous.

Uhh huh, still GM continues to not pin/keyway the crank pulley on standard engines. You would think the millons of engines sold a few cents to pin the crank pulley is nothing.

[radz28]

While I too share the same thoughts that I'd feel a lot better about LSA with forged slugs, I can easily understand that's probably why LS9 costs more because in order to make up for the extra forged pistons, it needs Ti rods (well, among the many other advancements and assembly techniques that it gets ). I'd like to find some of these other forums and see what luck they're having. Honestly, if I could get away with a very safe 550-600 RWHP with a stock longblock, pulley, CAI, tune, and exhaust, I'll have nothing to complain about. These engines come from GM really safe to start with. There's almost always a good amount of power, through tuning, on a stock car, to be had, safely, so I don't think it's necessarily imperative to have the longer list of short comings forged pistons have; I've dealt enough with piston slap and oil consumption to be done with that...

As far as running on the ragged edge, that's just asking for trouble. If you want everything the engine's got, that makes total sense, but I'm not sure that's the majority, and that's a risk that one has to accept on their own. Do I plan on pushing the car? As much as my $$$ will pay for. Will I run it outside of it's safety zone? Not intentionally. It's not a race car, nor do I think GM should build a racecar, tune it for everything it's got, and sell it as a street car. BIW is for that (well, I guess you have to build it).

Also - I hardly think Mr. Ed Welburn is some random person... (and yes - no one has announced it, officially, and someone else has already said that it's pretty common knowledge that's what's been in prototypes in the past, so I think it's pretty safe to say that's what we're getting. No need to be argumentative and go off the topic of this thread).

How about we get the best pistons for the buck and add a 2300? Just a though

[HaveBlue]

So if we have to have the forged pistons because the GT500 does, does that mean we have to have the iron truck block too?

[HaveBlue]

This surprised me a little. I didn't realize how many parts changes there were from the LS7 and even between the LSA & LS9.


"The lower pressures mean that some of the material changes that were implemented on the LS9 were not necessary on the LSA. The titanium connecting rods and intake valves are replaced by forged powdered metal and SilChromel, respectively. The exhaust valves on the LSA are not sodium filled either. The exhaust manifolds are cast iron rather than stainless steel as on the LS9 and the main bearing caps are nodular iron rather than steel.

The pistons in the LSA are hyper-eutectic cast aluminum rather than being forged. The piston skirts are polymer coated for improved scuff resistance and reduced NVH. The sumped top design of the pistons is retained, which allows for clearing the valves without machined valve pockets. The continuous surface free of edges helps to avoid hot spots that can contribute to pre-ignition.

The LSA also gets the dual pressure fuel system used in the the LS9, but the top pressure is reduced from 600kPa to 450kPa. The LSA gets the same beefed up block casting, seven-layer head gasket and 12mm head bolts as its big brother. The improved lubrication system including the squirters that spray oil on the bottom of the pistons is also retained. In total, the LSA and LS9 have about 100 new part compared to the LS7 in the current Corvette Z06. Of those, about twenty-five percent are common to both engines."

[radz28]

Originally Posted by HaveBlue

So if we have to have the forged pistons because the GT500 does, does that mean we have to have the iron truck block too?

No - we get the old 8.1L Big Block I guess it comes down to how it's marketed, eh?

Originally Posted by HaveBlue

This surprised me a little. I didn't realize how many parts changes there were from the LS7 and even between the LSA & LS9.


"The lower pressures mean that some of the material changes that were implemented on the LS9 were not necessary on the LSA. The titanium connecting rods and intake valves are replaced by forged powdered metal and SilChromel, respectively. The exhaust valves on the LSA are not sodium filled either. The exhaust manifolds are cast iron rather than stainless steel as on the LS9 and the main bearing caps are nodular iron rather than steel.

The pistons in the LSA are hyper-eutectic cast aluminum rather than being forged. The piston skirts are polymer coated for improved scuff resistance and reduced NVH. The sumped top design of the pistons is retained, which allows for clearing the valves without machined valve pockets. The continuous surface free of edges helps to avoid hot spots that can contribute to pre-ignition.

The LSA also gets the dual pressure fuel system used in the the LS9, but the top pressure is reduced from 600kPa to 450kPa. The LSA gets the same beefed up block casting, seven-layer head gasket and 12mm head bolts as its big brother. The improved lubrication system including the squirters that spray oil on the bottom of the pistons is also retained. In total, the LSA and LS9 have about 100 new part compared to the LS7 in the current Corvette Z06. Of those, about twenty-five percent are common to both engines."

I think those changes, though not minor, are what make it a great, affordable candiate for Z28. There are, really, only two things I'd love for GM to bring into Z28 for LSA, but there's nothing wrong, in the least, with what's there now, IMO.

[rodimus prime]

Emissions will have 0 effect from either piston. Thats redicules.

The one thread I would like ford guys in and they are nowhere to be found.

Why would you want a lesser quality product when you could have a safer motor for maybe a couple hundred bucks more?

I mean they could put single exhaust on the camaro to make it cheaper. It worked on 4th gens. They could cheaper brakes on the 5th gen...why do we need brembos when most people wont drive it to the limits of its stopping ability. Why should the majority have to pay for what few will use?..Sound familar?

For that matter why put an ls3 in the camaro...few will take it to the track. So the car doesnt need all the power.



HELLO 6 CYLINDER CAMARO!!!! For people that want the looks without the performance.

HELLO SS for people that want a well priced sports car.

HELLO Z28 for people that want a car to beat on GT500s. In order to beat on the compitition you need to be at least.......at the very least equal with it as far as features and benifits.

Forged pistons would be a feature.

Less worry about gernading your motor would be the benifit. A huge one at that. The iffy guy looking between the z28 and the GT500 would probably go with the GT500 because they would sell the shit out of the motor being forged and sell them on doubt with the non-forged z28 motor.

"I can understand that you like the looks of the z28 a bit more over the gt500, however wouldnt you feel more comfortable knowing that you have a fully forged motor that you dont have to worry about breaking if you decide to modify it some"

Thats all a salesman would have to say to a guy on the fence between the two.

[Super83Z]

You guys, alot of you need some education in engines. Hop on over to LS1tech and see what the guys in the FI section think of the hyperpukeit pistons that are in the LS1/LS2/LS3/LS6.

The price difference is laughable, only a few hundred dollars. Whatever any of you want to dream up for cons, the pros FAR FAR outweigh them.

[Mr. Wyndham]

Originally Posted by Super83Z

Hop on over to LS1tech and see what the guys in the FI section think of the hyperpukeit pistons that are in the LS1/LS2/LS3/LS6.

Are they the same as the pistons in the LSA? Just curious...

[Super83Z]

I just hope they think long and hard about this one. I don't want to see another 10-bolt like weaklink that keeps the cars from being great.

Performance cars should get performance parts.

The only reason the Cadillac got the Hypers is for NVH. That won't be an issue with the Z28.

[Mr. Wyndham]

Originally Posted by Super83Z

They are different diameters and probably piston heights, but the material that they are made of is the same.

That's strange...that they would use the same material in an engine 150hp+ more powerful than any of those listed...

[Super83Z]

Originally Posted by Dragoneye

That's strange...that they would use the same material in an engine 150hp+ more powerful than any of those listed...

Its more of a treatment, silicone is injected into a casting. T-6 is like a 30% silicone injection. Others are around 12-15%. Its still a weaklink in an otherwise awesome engine.

[rodimus prime]

Why is it strange for penny pinching gm? They used the same 10 bolt for camaros making 90hp more on an already stressed rear-end. Why would they put a tr6060 in a car thats right at the max rated torque output?

Ill tell you why. Because its GM.