991.2 RSR details announced in LA
11-16-2016, 09:33 PM
#31
Three Wheelin'
The mid body engine location is also usually conducent to better tire wear. That will allow these cars to double/triple stint their tires thus reducing overall pit stop times.
11-16-2016, 10:04 PM
#32
Platinum Dealership
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Let's look at it from a Chevy V8 perspective. The more cylinders you have, the more surface area you have, therefore making each stroke slightly less efficient. you have more cylinders to cool, more surface area to cool, and lubricate, which means you need more plumbing, and more sensors, etc. The Vette engines are really hard to keep cool, which is why they have to go to such extreme measures to evacuate hot air from the engine bay, blow cold air across the exhausts, etc.
The reason why an 8 liter engine (like the viper) does not make 1000hp (without grenading, at least) is because with all that mass and surface area, it's not really durable at 8500rpm the way a porsche engine is.
The cooler you can keep the surface area of the pistons, cylinder sleeves, etc the more consistent you will make power- just because you have forced induction does not mean you are immune to this principle, in fact it is quite the opposite as a turbo engine requires even more cooling, even more plumbing, even more complexity...etc.
So, my understanding is that, Porsche is just fine running the smallest engine.
11-16-2016, 10:12 PM
#33
Let's look at it from a Chevy V8 perspective. The more cylinders you have, the more surface area you have, therefore making each stroke slightly less efficient. you have more cylinders to cool, more surface area to cool, and lubricate, which means you need more plumbing, and more sensors, etc. The Vette engines are really hard to keep cool, which is why they have to go to such extreme measures to evacuate hot air from the engine bay, blow cold air across the exhausts, etc.
The reason why an 8 liter engine (like the viper) does not make 1000hp (without grenading, at least) is because with all that mass and surface area, it's not really durable at 8500rpm the way a porsche engine is.
The cooler you can keep the surface area of the pistons, cylinder sleeves, etc the more consistent you will make power- just because you have forced induction does not mean you are immune to this principle, in fact it is quite the opposite as a turbo engine requires even more cooling, even more plumbing, even more complexity...etc.
So, my understanding is that, Porsche is just fine running the smallest engine.
The reason why an 8 liter engine (like the viper) does not make 1000hp (without grenading, at least) is because with all that mass and surface area, it's not really durable at 8500rpm the way a porsche engine is.
The cooler you can keep the surface area of the pistons, cylinder sleeves, etc the more consistent you will make power- just because you have forced induction does not mean you are immune to this principle, in fact it is quite the opposite as a turbo engine requires even more cooling, even more plumbing, even more complexity...etc.
So, my understanding is that, Porsche is just fine running the smallest engine.
11-16-2016, 10:15 PM
#34
Three Wheelin'
Thats great reading CJ... I have always held guarded optimism when it came to the GT division in the next few years.
I gotta ask... When did Porsche make the head lights yellow and why are they yellow?
I gotta ask... When did Porsche make the head lights yellow and why are they yellow?
11-16-2016, 10:21 PM
#35
11-16-2016, 10:51 PM
#36
Drifting
Let's look at it from a Chevy V8 perspective. The more cylinders you have, the more surface area you have, therefore making each stroke slightly less efficient. you have more cylinders to cool, more surface area to cool, and lubricate, which means you need more plumbing, and more sensors, etc. The Vette engines are really hard to keep cool, which is why they have to go to such extreme measures to evacuate hot air from the engine bay, blow cold air across the exhausts, etc.
The reason why an 8 liter engine (like the viper) does not make 1000hp (without grenading, at least) is because with all that mass and surface area, it's not really durable at 8500rpm the way a porsche engine is.
The cooler you can keep the surface area of the pistons, cylinder sleeves, etc the more consistent you will make power- just because you have forced induction does not mean you are immune to this principle, in fact it is quite the opposite as a turbo engine requires even more cooling, even more plumbing, even more complexity...etc.
So, my understanding is that, Porsche is just fine running the smallest engine.
The reason why an 8 liter engine (like the viper) does not make 1000hp (without grenading, at least) is because with all that mass and surface area, it's not really durable at 8500rpm the way a porsche engine is.
The cooler you can keep the surface area of the pistons, cylinder sleeves, etc the more consistent you will make power- just because you have forced induction does not mean you are immune to this principle, in fact it is quite the opposite as a turbo engine requires even more cooling, even more plumbing, even more complexity...etc.
So, my understanding is that, Porsche is just fine running the smallest engine.
11-17-2016, 12:25 AM
#38
Burning Brakes
Is it possible the 991.2 gt3 will have this engine rated at 510 hp?
Just referenced to this post from two months ago.
https://rennlist.com/forums/991-gt3-...l#post13615827
Just referenced to this post from two months ago.
https://rennlist.com/forums/991-gt3-...l#post13615827
11-17-2016, 01:03 AM
#40
Addict
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Rennlist Member
I think it's possible. Seems like the next GT3 will make somewhere between the Cup and the RSR (485-510hp). That's only a spread of 5% and not likely to make a big difference either way. I'd like to know why the RSR makes 25hp more than the Cup. Is it something exotic like 6 Individual Throttle Bodies like past RSR's or just a matter of tuning, exhaust, intake restrictions, Rev Limits? Would be great if the power starts with a 5...
11-17-2016, 01:07 AM
#41
Drifting
11-17-2016, 01:30 AM
#42
I think it's possible. Seems like the next GT3 will make somewhere between the Cup and the RSR (485-510hp). That's only a spread of 5% and not likely to make a big difference either way. I'd like to know why the RSR makes 25hp more than the Cup. Is it something exotic like 6 Individual Throttle Bodies like past RSR's or just a matter of tuning, exhaust, intake restrictions, Rev Limits? Would be great if the power starts with a 5...
I still think the 991.2 gt3 will be tuned more for torque than hp like the cup with a drop in max rpm. This is good for marketing to explain the 8500rpm limit without having to talk about durability.
No doubt it has a 911 profile (NASCAR requirement) but is that enough? I guess it doesn't really matter what they call it.
11-17-2016, 01:46 AM
#43
Addict
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Rennlist Member
I agree that the motor will more closely resemble the Cup, but doesn't mean the outputs of the two will be identical...
11-17-2016, 02:51 AM
#44
Just thinking out loud here: I've been simmering over the words of FSW about this RSR not needing a waver or anything of that sort to run the RSR next year. I've been wondering and thinking that maybe they used a Cayman instead to homologate the car. After all, they Cayman shares much in common with a 911 from the rear bulkhead forward. Anyone with better insight could chime in...
11-17-2016, 03:13 AM
#45
Drifting
Is it possible the 991.2 gt3 will have this engine rated at 510 hp?
Just referenced to this post from two months ago.
https://rennlist.com/forums/991-gt3-...l#post13615827
Just referenced to this post from two months ago.
https://rennlist.com/forums/991-gt3-...l#post13615827
I think it's possible. Seems like the next GT3 will make somewhere between the Cup and the RSR (485-510hp). That's only a spread of 5% and not likely to make a big difference either way. I'd like to know why the RSR makes 25hp more than the Cup. Is it something exotic like 6 Individual Throttle Bodies like past RSR's or just a matter of tuning, exhaust, intake restrictions, Rev Limits? Would be great if the power starts with a 5...
But isn't the RSR engine running without variable valve timing? This won't happen in the production car.
I still think the 991.2 gt3 will be tuned more for torque than hp like the cup with a drop in max rpm. This is good for marketing to explain the 8500rpm limit without having to talk about durability.
No doubt it has a 911 profile (NASCAR requirement) but is that enough? I guess it doesn't really matter what they call it.
I still think the 991.2 gt3 will be tuned more for torque than hp like the cup with a drop in max rpm. This is good for marketing to explain the 8500rpm limit without having to talk about durability.
No doubt it has a 911 profile (NASCAR requirement) but is that enough? I guess it doesn't really matter what they call it.
All of the GTE/GTLM engines can/would make vastly more than 500 bhp without the sonic restrictors that are used to, ostensibly, "equalize" performance through BOP.
The outgoing 2016 RSR redlined a LOT higher than the street cars, and I'm sure this one does too.