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But I appreciate all the reminders! But tell me, you NEVER feel like stomping it at a light? Never??
Honestly? I used to a long time ago (I'm in my 40s now). Just learned over time that it's really not that fun or worth it. I'll still "stomp it" when I'm by myself, but I'll never do it to compete with someone else (I guess I just don't need the ego boost/confirmation).

Granted, I've done lots of track days (car and motorcycle), so that might play a large part in changing my mentality (which is why I was suggesting the same to you).

I guarantee you'll love it. The only downside is that it's addicting!
 

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Hi @ExpertRanch, I certainly get the desire for performance versus others...Our Engineering Director on the Ford GT used to say, "The Flesh is Weak" when you give a performance car to a gearhead. But as many have noted, the track is the best place to push these machines for so many reasons including the fact that they are road course style cars versus straight line only.

This is a topic I have worked on a lot so I have written a bit. Of importance - my perspective is from a full vehicle and vehicle behavior standpoint versus just engine/power. My bias - full vehicle.

Running on the street is pretty easy on these cars and powertrains versus a hot day at the track for many laps. So I will bias a bit of my answers to straight line for short bursts here, but for the overall vehicle performance it is dominated by weight, tire performance, center of gravity height, weight distribution and suspension. Weight, CG height and weight distribution take noticeable hit with supercharged system (versus naturally aspirated), especially if cooled properly.

Durability and Heat
Yes you should be concerned with this, but much less of an issue on the street versus the track. For durability I look at complexity - the number and sophistication of interfaces, which superchargers (or turbocharged) add a lot of complexity in general versus naturally aspirated. Will talk about durability of other powertrain elements below.

Heat Rejection
Heat rejection is directly proportional to Horsepower in the combustion chamber. So if you double the horsepower then you will need to reject twice as much heat. Just physics.

And if you are supercharged by the roots or screw type shown below then the combustion chamber will be seeing another ~100 HP more than you do at the crank due to the losses running off of the crank or more in this HP range. So you need to cool for far more than at the crank. These two types are show in Engineering Explained below.

However, this TTS twin centrifugal claims extremely high efficiency, which doesn't make sense to me because of the 200,000 RPM range these turbo like compressors are running (heat) and still running off of the crank. As Engineering Explained shows here the centrifugal type creates peak boost and power at peak power climbing from zero whereas Roots and Screw type have full boost at zero RPM (why they make sense for drag racing). TTS claims higher boost than other centrifugals at low RPM, but I didn't see their power curves on their website. Whereas VF Engineering shows their HP and Torque curves.

Regardless I am skeptical on the cooling systems being upgraded enough to deal with so much more power and run hard at the track. Since you are running it on the street mainly it is probably fine, which is what some manufacturers bank on. But someone who actually runs these hard on the track for at least 30 minute sessions in mid-summer of a humid hot climate (or track at some altitude in the summer) would have to speak to the overheating you ask about. I could overheat a specific supercharged supercar (stock) at Miller Motorsports Park (altitude - 4000 ft) in one lap if I pushed it hard in the summer. Big torque though so I ran in one taller gear and was OK. Just a little slower. No issue on the street.

Durability of the Rest
Anything much over the stock V10+ HP/Torque and there are notable failure modes including the front (Quattro) and rear drop gears in both transmissions fail a bit on higher HP (700-800 HP) per John at HCF auto. They have stronger drop gear options because of this need. I can't speak to half-shafts and the rest, but sticky tires/pavement and shock loading can hurt a lot of parts.

Putting Power to the Ground
I always say that it doesn't matter how much power you have if you can't put it to the ground. So if you are going to add a bunch of power then give me a call for our Ohlins TTX Suspension!

Induction Noise
Do you like the supercharger whine? Many do. Many do not. I do not - another disclosed bias of mine. To me the induction noise and AWE exhaust on our 2012 R8 V10 6MT from 5000 RPM up to 8500 RPM is world class. Sounds like an F1 car in a tunnel. Incredible.

Naturally Aspirated
You asked about the Ferrari 458 and its ~R8 V10 HP out of a 4.5 L and I noted cost, maintenance and 9000 RPM redline. Should have also noted ECU tuning. Does anyone do a higher revving pushed harder version of the R8 V8? Weight, CG height, weight distribution, efficiency, induction noise, NVH, heat/cooling required and durability (if all truly engineered) is superior with the naturally aspirated engine for the same to similar area under the curve power (not just peak HP) for any full vehicle analysis I have ever done. Seems like this would be a very rare build and vehicle but not reversible. But yes, Superchargers are very popular and many love them as well as often being reversible with a bit of work.

Your Financial Comparison
I get your math and comparison giving you about a $39k difference to build the V8 car...I would get input from customers and understand their usage of whichever path you are considering. And have good data like VF Engineering provides. For my track and performance usage and the visceral experience...the V10 with Plus ECU tune and exhaust is pretty hard to beat. And think it will hold or gain its value best of the options out there.

Engineering Explained - Supercharger Comparison

Engineering Explained Supercharger comparison

Some of Engineering Explained SC descriptions - these are versus each other. Not versus Normally Aspirated.
260396


260397




VF Engineering R8 V8 SC HP and torque curves - what any engine builder/tuner should easily provide. Personally, I would ask to see engineering calculations and data for heat rejection needs and resultant cooling upgrades as well. But I am guessing that is not as commonly provided to customers. That is where finding someone pushing them at the tracks on hot summer days is important if you think you have a good chance of going to the track

260398
 

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Discussion Starter #23 (Edited)
Hi @ExpertRanch, I certainly get the desire for performance versus others...Our Engineering Director on the Ford GT used to say, "The Flesh is Weak" when you give a performance car to a gearhead. But as many have noted, the track is the best place to push these machines for so many reasons including the fact that they are road course style cars versus straight line only.

This is a topic I have worked on a lot so I have written a bit. Of importance - my perspective is from a full vehicle and vehicle behavior standpoint versus just engine/power. My bias - full vehicle.

Running on the street is pretty easy on these cars and powertrains versus a hot day at the track for many laps. So I will bias a bit of my answers to straight line for short bursts here, but for the overall vehicle performance it is dominated by weight, tire performance, center of gravity height, weight distribution and suspension. Weight, CG height and weight distribution take noticeable hit with supercharged system (versus naturally aspirated), especially if cooled properly.

Durability and Heat
Yes you should be concerned with this, but much less of an issue on the street versus the track. For durability I look at complexity - the number and sophistication of interfaces, which superchargers (or turbocharged) add a lot of complexity in general versus naturally aspirated. Will talk about durability of other powertrain elements below.

Heat Rejection
Heat rejection is directly proportional to Horsepower in the combustion chamber. So if you double the horsepower then you will need to reject twice as much heat. Just physics.

And if you are supercharged by the roots or screw type shown below then the combustion chamber will be seeing another ~100 HP more than you do at the crank due to the losses running off of the crank or more in this HP range. So you need to cool for far more than at the crank. These two types are show in Engineering Explained below.

However, this TTS twin centrifugal claims extremely high efficiency, which doesn't make sense to me because of the 200,000 RPM range these turbo like compressors are running (heat) and still running off of the crank. As Engineering Explained shows here the centrifugal type creates peak boost and power at peak power climbing from zero whereas Roots and Screw type have full boost at zero RPM (why they make sense for drag racing). TTS claims higher boost than other centrifugals at low RPM, but I didn't see their power curves on their website. Whereas VF Engineering shows their HP and Torque curves.

Regardless I am skeptical on the cooling systems being upgraded enough to deal with so much more power and run hard at the track. Since you are running it on the street mainly it is probably fine, which is what some manufacturers bank on. But someone who actually runs these hard on the track for at least 30 minute sessions in mid-summer of a humid hot climate (or track at some altitude in the summer) would have to speak to the overheating you ask about. I could overheat a specific supercharged supercar (stock) at Miller Motorsports Park (altitude - 4000 ft) in one lap if I pushed it hard in the summer. Big torque though so I ran in one taller gear and was OK. Just a little slower. No issue on the street.

Durability of the Rest
Anything much over the stock V10+ HP/Torque and there are notable failure modes including the front (Quattro) and rear drop gears in both transmissions fail a bit on higher HP (700-800 HP) per John at HCF auto. They have stronger drop gear options because of this need. I can't speak to half-shafts and the rest, but sticky tires/pavement and shock loading can hurt a lot of parts.

Putting Power to the Ground
I always say that it doesn't matter how much power you have if you can't put it to the ground. So if you are going to add a bunch of power then give me a call for our Ohlins TTX Suspension!

Induction Noise
Do you like the supercharger whine? Many do. Many do not. I do not - another disclosed bias of mine. To me the induction noise and AWE exhaust on our 2012 R8 V10 6MT from 5000 RPM up to 8500 RPM is world class. Sounds like an F1 car in a tunnel. Incredible.

Naturally Aspirated
You asked about the Ferrari 458 and its ~R8 V10 HP out of a 4.5 L and I noted cost, maintenance and 9000 RPM redline. Should have also noted ECU tuning. Does anyone do a higher revving pushed harder version of the R8 V8? Weight, CG height, weight distribution, efficiency, induction noise, NVH, heat/cooling required and durability (if all truly engineered) is superior with the naturally aspirated engine for the same to similar area under the curve power (not just peak HP) for any full vehicle analysis I have ever done. Seems like this would be a very rare build and vehicle but not reversible. But yes, Superchargers are very popular and many love them as well as often being reversible with a bit of work.

Your Financial Comparison
I get your math and comparison giving you about a $39k difference to build the V8 car...I would get input from customers and understand their usage of whichever path you are considering. And have good data like VF Engineering provides. For my track and performance usage and the visceral experience...the V10 with Plus ECU tune and exhaust is pretty hard to beat. And think it will hold or gain its value best of the options out there.

Engineering Explained - Supercharger Comparison
Engineering Explained Supercharger comparison

Some of Engineering Explained SC descriptions - these are versus each other. Not versus Normally Aspirated.
View attachment 260396

View attachment 260397



VF Engineering R8 V8 SC HP and torque curves - what any engine builder/tuner should easily provide. Personally, I would ask to see engineering calculations and data for heat rejection needs and resultant cooling upgrades as well. But I am guessing that is not as commonly provided to customers. That is where finding someone pushing them at the tracks on hot summer days is important if you think you have a good chance of going to the track

View attachment 260398
exactly the kind of info i was looking for. Thank you and I bet many others thank you for the breakdown. And I saw those videos while searching and waiting to hear back from you... they do a really good job of explaining how they all work. I've also read here at R8talk from Tom @speedrs4 about how it's possible to get 510hp out of the V8 with larger intake manifolds, and a few extra related modifications. I asked him if he has it all written down and he said I'll just have to read all of his posts. So I have 600+ posts to go through... If I can get 510hp without induction, then I'll do that. However, I now need to consider cooling as per your input above.
 

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Discussion Starter #24
Also, to be honest... I am going to be looking for a v10 while I search. If I can find a good trade, I may just go for it.
 

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exactly the kind of info i was looking for. Thank you and I bet many others thank you for the breakdown. And I saw those videos while searching and waiting to hear back from you... they do a really good job of explaining how they all work. I've also read here at R8talk from Tom @speedrs4 about how it's possible to get 540hp out of the V8 with larger intake manifolds, and a few extra related modifications. I asked him if he has it all written down and he said I'll just have to read all of his posts. So I have 600+ posts to go through... If I can get 540hp without induction, then I'll do that. However, I now need to consider cooling as per your input above.
Glad my input was on target for your questions.

Yes cooling should be upgraded proportionally when upgrading HP unless it was already oversized. However, running on the street is far easier on the car and cooling than the track generally...except for sitting in stop and go traffic on a hot and humid summer day...or up in altitude.

I wouldn't be quite as afraid of miles as many seem...a car that is driven a bit has less issues than those that sit a lot. Very hard for us engineers to design and test for the cars sitting a lot. (We don't have the luxury of time for long term testing of that nature). Our 2012 V10 had 17k miles on it when we got it the summer of 2019. Had a PPI done and exotic car friend check it out (far from my home). Such a great car.

Good luck in your quest for more power.
 

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Discussion Starter #26
I just found a V10 with 33k miles for $103k so I can get to 550 hp for $12k :) ... Now... how to get this done without freaking my wife out. That is the trick! She is an accountant and paying sales tax twice in 4 months is not an easy sell.
 

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Hi

I always see the problem with the supersharger in the moment of indolence.

The larger the charger, the higher the mass and the higher the load on the belts and the pulleys for belts.

This is not a problem with an engine that slowly increases its speed, but if the engine is very fast in this discipline, the load is also higher.

With a motor that rotates up to 8500 rpm, the Superchrager with very good quality is necessary.


Tom
 

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Hi

I always see the problem with the supersharger in the moment of indolence.

The larger the charger, the higher the mass and the higher the load on the belts and the pulleys for belts.

This is not a problem with an engine that slowly increases its speed, but if the engine is very fast in this discipline, the load is also higher.

With a motor that rotates up to 8500 rpm, the Superchrager with very good quality is necessary.


Tom
TTS use Rotrex Tom.
 

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Discussion Starter #30
Hahaha It’s easier to ask for forgiveness than permission
Normally I agree... but I am a risk taker by nature and an entrepreneur and in our 18 years of marriage, I may have taken a few years off her life span!... So this time... I played it from a distance so nothing could fly at me... I sent her an email with a spread sheet. ha hahahahahh so far silence... but I have a feeling I'm gonna get stink eye tonight for sure. Oh well... I just need to not blink first! ha hahahhahah HERE WE GO! ha hahahahah

At least I didn't ask her if I could get the new one while I still have my other new one until I can sell it!
 

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Normally I agree... but I am a risk taker by nature and an entrepreneur and in our 18 years of marriage, I may have taken a few years off her life span!... So this time... I played it from a distance so nothing could fly at me... I sent her an email with a spread sheet. ha hahahahahh so far silence... but I have a feeling I'm gonna get stink eye tonight for sure. Oh well... I just need to not blink first! ha hahahhahah HERE WE GO! ha hahahahah

At least I didn't ask her if I could get the new one while I still have my other new one until I can sell it!
Hahaha I hear you- I get yelled at whenever she sees me browsing BAT in bed at night. When I brought the R8 home next to my stage iv TTrs, it ended up costing me a upgrade of her car to a Macan gts as well... and I still catch sarcastic comments here and there. She assured me that if I bring home something like a manual lp640 I was eyeing that I should bring a coffin with me as well. Oh well. At least she doesn’t know how much the mods to the car cost hahaha
 

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I just found a V10 with 33k miles for $103k so I can get to 550 hp for $12k :) ... Now... how to get this done without freaking my wife out. That is the trick! She is an accountant and paying sales tax twice in 4 months is not an easy sell.
i hope it all works out great! Keep us posted.
 

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+1 on enjoy what you drive. There's always someone with more $$ going faster. I have a Supercharged V10, love it, perfect for me. I've went back and forth on FB, which I hate because some people are debating on whether 1000 HP or 1500 HP is enough in the R8. At that point, when is it enough. The next guy rolls by with 2500 HP, time for a new TT setup and full engine build. I love the VF unit on my car. Daily driver reliability with pin you in the seat performance when you want it. Just push the pedal to the floor. As far as those PITA guys go, trying to race me on Route 80, I wave them on. Been there done that. I had a 1/4 mile drag car for a long time and have come to appreciate the skill required to drive fast on the track. I like to have the extra power, but a guy with a properly setup car that can drive will beat me in the corners all day long. I am loving the challenge and it's definitely addictive.
 
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