V6 Turboing

[MrIcky]

I thought the STS type turbos had some real benefits in aftermarket systems. The main one is that the exhaust gas is several hundred degrees cooler so the turbos don't have to be oil jacketed for fluid bearings. Therefore it's more straight forward as a bolt on, even though you might not be able to get quite as much power.

But in a fully plumbed system hot air in the exhaust in front of the turbo expands which creates more pressure on the turbine side so it spools faster. I actually understood that was more the reason for the lag, not the length of pipe.

As far as PSI, who knows- it's more airflow CFM then PSI. 5 PSI on a big housing can flow alot of CFM. And STS's run pretty large turbos. I see the appeal if you are trying to keep your engine as stock as possible.

Most of my turbo knowledge is from my truck though. I haven't messed with my car's turbo so I'm not sure if it 100% applies.

[09CobaltSS/Turbo]

Originally Posted by MrIcky

I thought the STS type turbos had some real benefits in aftermarket systems. The main one is that the exhaust gas is several hundred degrees cooler so the turbos don't have to be oil jacketed for fluid bearings. Therefore it's more straight forward as a bolt on, even though you might not be able to get quite as much power.

But in a fully plumbed system hot air in the exhaust in front of the turbo expands which creates more pressure on the turbine side so it spools faster. I actually understood that was more the reason for the lag, not the length of pipe.

As far as PSI, who knows- it's more airflow CFM then PSI. 5 PSI on a big housing can flow alot of CFM. And STS's run pretty large turbos. I see the appeal if you are trying to keep your engine as stock as possible.

Most of my turbo knowledge is from my truck though. I haven't messed with my car's turbo so I'm not sure if it 100% applies.

Big turbo systems hook the turbo right onto the Exhaust Manifolds. The bigger the displacement the less of an issue it is but here is a pic of a twin turbo v6 .. Done right .



Thats what I am saying ^ TT v6 ( porsche/VW )

[09CobaltSS/Turbo]

Originally Posted by Dragoneye

I know how it all works....

I was just referring to the design that STS uses in response to your hose anaolgy. The volume of the piping of their system is roughly the same as a traditional system plus an intercooler. They achieve this by using skinnier pipes on the return side.

Yes, it's farther away from the engine, so there's a heat loss, but they sized the turbo(s) specifically to work from back there, and consequently, the time it takes to pressurize the intake piping is the same as any other turbo system.

LOL I didn't even see your MOD status dude.

[speedster]

Pick up a copy of the latest issue of Hot Rod. The place that made the engine on the cover (Nelson Racing Engines) is making complete twin turbo setups for the SS Camaros.

[09CobaltSS/Turbo]

Originally Posted by speedster

Pick up a copy of the latest issue of Hot Rod. The place that made the engine on the cover (Nelson Racing Engines) is making complete twin turbo setups for the SS Camaros.

I'm trying to tell them the days of just slapping on a power adder on are here. A lot of companies are even starting to offer the option of a turbo charger on 75% of the entire line up of vehicles.... The future is here.

[Grape Ape]

Originally Posted by vladkgb

theres no way a turbo or super charger "bolt-on" kit will be made and still run on pump gas. its impossible because the v6 has 11:1 compression due to the direct injection, this engine wont be able to take much boost at all before detonation will be a big problem. If the v6 gets any type of forced induction expect atleast a head change to lower the compression ratio, which = big monies.

I saw a Canadian outfit the sells twin turbo upgrades for the VW R32 (AWD V6 Golf) that was offering head spacers on their higher HP kits. You might also need a new intake manifold (or more spacers) and longer timing chains/belts but still probably cheaper than head work.

But you might be able to kill two birds and swap in shorter, forged rods and/or pistons that would allow high boost by being stronger and by lowering compression.

But I don;t think there will be a problem with moderate levels of boost since as Dragoneye mentioned it runs fine on 87 octane. And more convincingly, there are already Cadillacs running around with blowers on the same V6.

[Grape Ape]

Originally Posted by Dragoneye

I know how it all works....

I was just referring to the design that STS uses in response to your hose anaolgy. The volume of the piping of their system is roughly the same as a traditional system plus an intercooler. They achieve this by using skinnier pipes on the return side.

Yes, it's farther away from the engine, so there's a heat loss, but they sized the turbo(s) specifically to work from back there, and consequently, the time it takes to pressurize the intake piping is the same as any other turbo system.

The intake piping might have the same volume as an inter cooler, but I'd rather have either an inter cooler cooling the air or a short pipe without one so the system could pressurize faster. This sounds like the worst of both worlds.

[fierodeletre]

The issue of compression is not traditional and should not be viewed as such. No fuel/air is compressed in a DI engine. This is the reason they went with the high C/R. Because they could get away with it, because it makes a higher specific output powerplant. Having the high C/R in a boosted setup really would only be a question of fuel pressure, since the new TDC cyl pressure would now be 5-25 PSI + 1 bar X 11.1 instead of < or = 1 bar X 11.1, and you'd have to be sure that the 1200 psi (I think) max fuel pressure would be enough to atomize into such a high-pressure volume of air. It's been said a thousand times before. They didn't "tune" the engine for 87 octane. You can run any octane you like in it. They use 87 because it's a great selling point for customers and it illustrates the brilliance of the idea. You can't detonate dry air. Again, the biggest hurdles to FI on the LLT will be sufficient fuel pressure and perhaps head gasket integrity, not C/R.

[Rock]

Your biggest issue is going to be fuel management and ecu tuning,depending on how hard the ecu is to crack. DI is also a relatively new technology, what we do know is you can run higher C/R due to much more accurrate and cleaner fuel burn directly into the combustion chambers. Hard part is you better hope that the stock Injectors can handle an increased fuel demand.
On my Mazdaspeed3 with a 2.3L DISI it has a 9.5:1 C/R that puts out 256/280 hp/torque. Not bad for a 4banger. It took about a year to get anytype of tuning out as well as fuel upgrades. However, one of the first modifications to help with the fuel problems and detonation was methanol injection. You will aslo probably want to change your plugs out for 1 or 2degree colder plugs and run on 93 octane. You will get huge power from going turbo. I'd put pricing for a kit at around 4500 minimum for a single turbo setup. More than likely going to come with a enginemanagement of some sort,turbo, turbo manifold, downpipe, intercooler, piping, possibly fuel upgrades, and various hoses,fittings,and clamps.

[THE EVIL TW1N]

Originally Posted by Rock

Your biggest issue is going to be fuel management and ecu tuning,depending on how hard the ecu is to crack. DI is also a relatively new technology, what we do know is you can run higher C/R due to much more accurrate and cleaner fuel burn directly into the combustion chambers. Hard part is you better hope that the stock Injectors can handle an increased fuel demand.
On my Mazdaspeed3 with a 2.3L DISI it has a 9.5:1 C/R that puts out 256/280 hp/torque. Not bad for a 4banger. It took about a year to get anytype of tuning out as well as fuel upgrades. However, one of the first modifications to help with the fuel problems and detonation was methanol injection. You will aslo probably want to change your plugs out for 1 or 2degree colder plugs and run on 93 octane. You will get huge power from going turbo. I'd put pricing for a kit at around 4500 minimum for a single turbo setup. More than likely going to come with a enginemanagement of some sort,turbo, turbo manifold, downpipe, intercooler, piping, possibly fuel upgrades, and various hoses,fittings,and clamps.

I think the prices for a turbo upgrade will be closer to $6000+.

[09CobaltSS/Turbo]

Originally Posted by THE EVIL TW1N

I think the prices for a turbo upgrade will be closer to $6000+.

If we are lucky

[Grape Ape]

Originally Posted by fierodeletre

The issue of compression is not traditional and should not be viewed as such. No fuel/air is compressed in a DI engine. This is the reason they went with the high C/R. Because they could get away with it, because it makes a higher specific output powerplant. Having the high C/R in a boosted setup really would only be a question of fuel pressure, since the new TDC cyl pressure would now be 5-25 PSI + 1 bar X 11.1 instead of < or = 1 bar X 11.1, and you'd have to be sure that the 1200 psi (I think) max fuel pressure would be enough to atomize into such a high-pressure volume of air. It's been said a thousand times before. They didn't "tune" the engine for 87 octane. You can run any octane you like in it. They use 87 because it's a great selling point for customers and it illustrates the brilliance of the idea. You can't detonate dry air. Again, the biggest hurdles to FI on the LLT will be sufficient fuel pressure and perhaps head gasket integrity, not C/R.

Here is a link to GM's data sheet for the LLT: http://media.gm.com/us/powertrain/en...6/09_LLT_n.doc

They say that the fuel is injected during the intake stroke, while the intake valve is open. This still allows all of the fuel vaporization's cooling to go into the air instead of the intake valve which doesn't need it. The rest of the gains appear to have been made the hard way: better cooling of the chamber (like the oil jets squirting the bottoms of the pistons).

[fierodeletre]

I didn't go through it, but if that is true, why do they use such a high pressure fuel pump and injectors? Technically in a NA engine that air charge would be in vacuum.

[09CobaltSS/Turbo]

Originally Posted by fierodeletre

I didn't go through it, but if that is true, why do they use such a high pressure fuel pump and injectors? Technically in a NA engine that air charge would be in vacuum.

Because it is like a Diesel .. Normal injectors squirt the fuel in the opposite stroke towards the bottom. DI has a VERY VERY small window of time to get the fuel into the cylinder. we are talking quarters of a milisecond to get the exzact amount of fuel for every stroke .. VERY complex