Who's holding out for the Supercharged LSA?

[radz28]

Originally Posted by Wm Holden

That's kinda why I put up the homemade turbo video...he's already lunched a couple of connecting rods....but it was cheap.

EEKK!!! I'm sure that hurt. I haven't got a chance to watch the video, but will have to make time for that.

[Wm Holden]

It's only 30 seconds...no big deal.

But peace of mind is (a big deal)...that's why I paid the price I did instead of "Fabbing" something.

[radz28]

Originally Posted by Wm Holden

It's only 30 seconds...no big deal.

But peace of mind is (a big deal)...that's why I paid the price I did instead of "Fabbing" something.

I'll get a look at home; I can't view a lot at work.

I totally see you on the piece of mind. When it comes to engineering, I leave it up to a company like GM when it comes to making reliable and long lasting power, that's why I'm Hell-bent. You bring up a great point though about keeping options open, because frankly, if I can't get what I want, I'll be going to the company GM uses to make it's superchargers

[Wm Holden]

Originally Posted by radz282003

I'll get a look at home; I can't view a lot at work.

I totally see you on the piece of mind. When it comes to engineering, I leave it up to a company like GM when it comes to making reliable and long lasting power, that's why I'm Hell-bent. You bring up a great point though about keeping options open, because frankly, if I can't get what I want, I'll be going to the company GM uses to make it's superchargers

Thank You for the kind replies Radz...and I TRUELY hope you get everything you want.

[GTAHVIT]

Stock numbers.

LS2 CR 10.9 : 1, LS3 CR 10.7 : 1, LSA CR 9.1 : 1

Hmmm. I'm wondering how much boost..... Any one think the LS3 can handle 10psi, innercooled, pump gas, without lowering the CR???

LS2

I found this post from an LS2 Corvette thread, Asking the question, "how much boost can a stock ls2 safely handle?" They all seem to agree that Less than 8 is safe 10/11 is reasonable... The post below is a great explanation of how much boost is really necessary... Good read.

That's like asking "how many rocks can you carry?". I'd want to know the size of the rocks before I answer that question.
One interesting thing about high HP cars that most people bragging about the big power numbers don't seem to realize is that your 500/600/800/whatever HP Corvette is hardly making that much power, ever. Say you run 10PSI: The tires will break lose in 1st 2nd and 3rd before any real load gets put on the engine, and even if they didn't, 1st 2nd and 3rd will go by in about 5 seconds and then you will be well over the posted speed limit on any road in this country. If you get on it in 4rth you will be able to put some really good load on the engine and stress things, but you won't see 10PSI in 4rth with a 10PSI pulley until 150MPH, and I am willing to be 90% of the members on this forum have never seen that on their speedometers.
Take it to the 1/4 mile track and the situation changes a little bit, but not much. Between wheel spin in 1st and 2nd and the fact that you won't cross the traps at redline in 4rth, you might see 2-3 seconds of 10PSI under full engine load with the average boost being much lower.
I bet the average 600+ RWHP Corvette owned by the average Corvette owner on this forum sees peak boost under load for a few dozen seconds A YEAR. Sounds ludicrous? Remember to see peak boost you have to be at redline and to see it under load you have to be at redline under full throttle in a gear that provides you with complete traction. That's 90MPH if you can hook 3rd and are willing to ride 3rd past 6000RPMs or 150MPH if you stay in 4rth gear past 6000RPMs and don't shift into 4rth.

Under those conditions a tuner can build you a car that makes a TON of power knowing that it will never make a ton of power for very long so repetitive stresses on components, and, most importantly, thermal considerations aren't too much of a concern.

On the other hand if you get that 10PSI stock engine block car and attempt to run a high speed track event with it, or try some high speed highway pulls, it will be a matter of short time until it blows up.

I got some real world experience on this running 21PSI on 93 octane on my 9:1 compression Subaru STI. It was SUPER fast (around 200hp/L on a 2L engine and a 2740lbs car) and ran around town great. But it blew up twice when I tried full boost 5th gear pulls. The second time around the engine completely destroyed itself at 177MPH in 5th gear. Most people don't realize how incredibly stressful big power numbers are on their engines. Let me illustrate:
600RWHP = Circa 700crank HP (not quite but we'll use that nice round number as an approximation) = 521Kilowatts. A typical internal combustion engine is maybe 20% efficient at best, so as it makes 521kw that engine is producing just shy of 1million watts of heat.
1 million watts of heat under your hood is approximately equivalent to the amount of heat output you would get from having, say, 10,000 100 watt lightbulbs under your hood, or 1000 toasters or 1000 hairdriers or about 600 plug-in space heaters, all producing heat under your hood. Things get really hot really fast with all that heat, specially when it all needs to be carried out of the combustion chamber before it becomes too hot and starts to pre-ignite the fuel...


So, to answer your question: Instead of looking for a quick answer that may or may not have any value to you, think about how you drive the car and how long you need it to last, and then decide how much boost you want to run

That said o0Zeno0o s numbers are a good ballpark for a street car... (7/8 psi)

LS3

Again, a corvette article but applicable to those of us who may have to go aftermarket on the blower.

I like these numbers.

SUPERCHARGED 2008 LS3!


Tony’s Corvette Shop has just completed it's first installation and tuning of a supercharger on the new 2008 Corvette with the LS3 engine. The Procharger P1SC was installed and produced approximately 5 psi of boost pressure at 6300 rpm. Larger fuel injectors were installed, however, stock fuel pressure was maintained. As expected, the LS3 responded well producing 550 rear wheel horsepower and 512 ft/lbs of torque on an industry comparable basis. This is an increase of 154 hp over the comparable stock runs.

Technical Specifications:

2008 Corvette, LS3 6.2L, 10.5 /1.0 compression
6 speed
Long Tube Headers, High Flow Cats, X-pipe and Corsa Mufflers
ATI ProCharger P1SC with 5 psi boost
Fuel: 93 octane at stock fuel pressure

Metrics

Date 9-05-07
Temperature – 94 degrees
Humidity – 29.6%
Barometric Pressure – 29.37 in/Hg
Dyno: SuperFlow 840 in a calibrated laboratory environment

There's no mention of an intercooler....

The Camaro LS3 has a little higher CR at 10.7 : 1. Any thoughts....

[boxmonkeyracing]

Originally Posted by gtahvit

Stock numbers.

LS2 CR 10.9 : 1, LS3 CR 10.7 : 1, LSA CR 9.1 : 1

Hmmm. I'm wondering how much boost..... Any one think the LS3 can handle 10psi, innercooled, pump gas, without lowering the CR???

LS2

I found this post from an LS2 Corvette thread, Asking the question, "how much boost can a stock ls2 safely handle?" They all seem to agree that Less than 8 is safe 10/11 is reasonable... The post below is a great explanation of how much boost is really necessary... Good read.



LS3

Again, a corvette article but applicable to those of us who may have to go aftermarket on the blower.

I like these numbers.



There's no mention of an intercooler....

The Camaro LS3 has a little higher CR at 10.7 : 1. Any thoughts....

exactly why the LS3 is my current aim for my 98. . .lol. but I still wouldn't mind my new one being able to out power my 98. just the way progression should be.

[radz28]

I think with a good tune, you could run around at 500+ RWHP on an LS3 without much worry. Those cranks are tough. I remember reading many articles with 800+ RWHP cars either on the boost or the bottle running on the stock crank and aftermarket rods and pistons. The boosted cars were always intercooled or had water/methanol injection. I think it would be plenty safe to run 6-8 lbs. of boost through an LS3 with a healthy fuel system and good tune. Who really knows though? If GM would just give us an LSA we could be done with this

[Mr. Wyndham]

On a side note; that first quote makes a HUGE point; one that, as a power-freak I disagree with...but one that, as guy with some common sense I can appreciate it 100%. You don't NEED eleventy-billion horsepower; and you certainly can't use it reliably, especially if you made it aftermarket.

It's part of the reason I'd be more than happy with a V6. And part of the reason I seek no more than 500hp...ever.

/thread jack

I've read numbers anywhere from 5psi to 8psi on a stock LS3. That's if you plan on keeping the car for any length of time. Any higher; and you're looking to blow it up.

I do plan on installing some sort of FI. I haven't decided which, yet; but whatever I do: an intercooler is a must imo. Water to air, air to air, whatever; but I won't take the chance of not using one.

[GTAHVIT]

I'm not jumping off the LSA, LS8 bandwagon. I'm just wondering what people think about an aftermarket solution.

I'm still of the opinion that if I can get it from the factory I will. Maybew GMPP will offer the 1900 or 2300 as a bolt on? That'd be the way I'd go if a LSA/8 isn't in the cards.

[radz28]

Originally Posted by gtahvit

I'm not jumping off the LSA, LS8 bandwagon. I'm just wondering what people think about an aftermarket solution.

I'm still of the opinion that if I can get it from the factory I will. Maybew GMPP will offer the 1900 or 2300 as a bolt on? That'd be the way I'd go if a LSA/8 isn't in the cards.

I'd be happy if I could add either of those and keep my GM warranty. If we could get away with that, throw it into the financing, I won't be complaining hardly at all