Audi R8 Forums banner

21 - 38 of 38 Posts

·
Vendor
Joined
·
511 Posts
Discussion Starter #21
Not that I would touch this car but to run the R8 on E85 does anything need to be changed? Would be good to know for those who are considering it (plus I'm curious). Fuel lines? Injectors? etc.
We didn't find the need to change anything. The fueling system has plenty of headroom. We've also tested other Audi platforms on E85 for several years straight and have found no need to change fuel lines.
 

·
Registered
Joined
·
1,149 Posts
We didn't find the need to change anything. The fueling system has plenty of headroom. We've also tested other Audi platforms on E85 for several years straight and have found no need to change fuel lines.
Interesting! Thanks Arin!

I read above it's one tune or the other (91/93 or E85) and not a flex-fuel type setup. Any easy way to integrate flex into the vehicle? I run flex on the GTR and a friend of mine didn't (one tune or the other) and it didn't seem to be the most optimal setup. Plus, if you get E85 from a station who's E% is significantly lower than anticipated that could be an issue. Locally I usually see 77-78% but the labels on the pump say minimum 51% so if you get a tank of ~55% or so I don't know how that would factor into the equation.
 

·
Vendor
Joined
·
511 Posts
Discussion Starter #23
You can run both summer and winter blends from E60 to E98 with this tune. However, it's not flex fuel, so don't mix and blend E85 with pump or race fuel.
 

·
Registered
Joined
·
329 Posts
Or let's get even more food for thought: A German car magazine (one of the most reputable ones) did a review of the MTM Audi R8 with over 800 hp (supercharged, basically the kit which is sold widely in the US). From 0-100 kph, the stock car was faster. From 0-150 kph, the stock car was faster. Only from 0-160 kph (100 mph), the tuned R8 gained a few milli(!)seconds. The real performance gain (around one second) was noticeable from 0-200 kph (125 mph). From 200 kph (125 mph) to 300 kph (188 mph), things look differently. This is where you actually gain performance. When did you (or the majority here in the forum) drive 125 to 188 mph lately? LOL
You previously posted the same faulty information ( http://www.r8talk.com/forums/138-2nd-generation-discussion/135810-first-vf-engineering-vf800-supercharged-2017-audi-r8-v10-spyder.html#post1240042 ). In response, both VF Engineering and I explained why your information was faulty. Tellingly, you declined to reply. Yet, here you are again reposted the same faulty information. As I said before:

Motor Trend recorded a 2.4 second 0-60 for a Huracan with the VF800 package. There is no reason why a VF800 R8 cannot replicate the same time. VF800s have also recorded sub 10 second quarter mile times at 145+ mph. Motor Trend timed an OEM R8 Plus at 2.6 0-60, and 10.6 in the quarter mile (Motor Trend timed an OEM Huracan at 2.8 0-60 and 10.6 in the quarter mile). A 0.2-0.4 second improvement 0-60, and 0.7+ second improvement in the quarter mile, are material gains in low end performance.

The German magazine that you refer to used the February 2016 Auto Bild test results for the OEM R8 as the benchmark for comparison. The car tested by Auto Bild was running Pilot Sport Cup II tires. Thus, not surprisingly, Auto Bild recorded the fastest times of any magazine for an OEM R8 -- no other magazine has recorded similar times, primarily because the other magazines tested the R8 on the OEM street tires. In contrast, the MTM car tested by the German magazine was running PS4S tires. The Cup tires have considerably better grip over the PS4S tires on the MTM car, and provide a material advantage when launching the car. I suspect the superior tires are why the OEM R8 recorded a better launch as compared to the MTM R8. Put the MTM car on Cups and the launch times would be meaningfully different (with the additional power, the MTM car needs the additional grip much more than the OEM car).

I am also informed that the German magazine tested the MTM car and the OEM car at different locations on different days, with different conditions. That makes all the difference.

I am also informed that MTM timed its car at 3.2 seconds 0-100 km before the supercharger, and 2.6 seconds 0-100 km after the supercharger, thus confirming a significant improvement in low end performance.

Lastly, the dyno chart for the VF800 further confirms a significant improvement in HP across the entire RPM range, including lower RPMs, thus further illustrating the corresponding increase in low end performance.



If you really believe an OEM R8 on OEM tires is faster than a supercharged R8 to 125 mph, I suggest a friendly wager. I can arrange the race (at an airstrip) -- some tire, same location, same day, side by side. I'll wager $10,000 on the supercharged R8. If you really believe what you posted, you should have no problem wagering $10,000 on the OEM R8. Or, we can bet more.

On the German Autobahn, these kits wouldn't survive for long, just imagine doing full throttle for a couple of minutes instead of a couple of seconds with a 800+ kit. Good luck with that!
More faulty speculation. There are supercharged and turbo R8s that are regularly tracked, and run full throttle for 30 minutes or longer, without the slightest problem.

I get it – you are not a fan of forced induction R8s. That is certainly your prerogative. However, repeatedly posting the same faulty information does not advance your opinion – it only undermines it.
 

·
Registered
Joined
·
108 Posts
Define "significant" loss? Main problem is: Once you do the mod, your warranty (at least engine, gearbox and drivetrain) is gone. Same goes to the "grace" warranty period some car manufacturers grant for major issues after the usual warranty runs out.
Look up the cost of a new V10 engine...you'll have the shock of your lifetime. ;)
If tuners tell you that the ECU mod is undetectable, they are lying. It is always detectable. Maybe not by the local dealer but once you have a major engine/gearbox/whatever failure, Audi will request certain ECU data and you're busted. Not worth it.
Just my personal opinion though, to each his own.

Btw: How would a 24 hp gain "translate" into real world performance on a 610 hp car? You will only feel it, MAYBE, in the upper speed range over 200 kph (125 mph). You need at least 10% more power to actually be able to feel it on such a car.

Or let's get even more food for thought: A German car magazine (one of the most reputable ones) did a review of the MTM Audi R8 with over 800 hp (supercharged, basically the kit which is sold widely in the US). From 0-100 kph, the stock car was faster. From 0-150 kph, the stock car was faster. Only from 0-160 kph (100 mph), the tuned R8 gained a few milli(!)seconds. The real performance gain (around one second) was noticeable from 0-200 kph (125 mph). From 200 kph (125 mph) to 300 kph (188 mph), things look differently. This is where you actually gain performance. When did you (or the majority here in the forum) drive 125 to 188 mph lately? LOL
I understand the passion of tuning pony/muscle cars, I had a 2013 Shelby GT500 myself, tuned to almost 750 hp but tuning a R8? What for? This is an amazing V10 n/a engined car, enjoy it like it is because in 10 years, such cars won't be made anymore. Instead people throw a turbo/supercharger on it, how crazy is that?!
True on the loss of warranty coverage-but I modded mine (a 2012) after the warranty ran out. And no, I wouldn't do a tune on a gen 2 R8 if I owned one if it made only 24 HP more, but that V10 can certainly handle 24 more HP.

As for your diatribe about being nuts to supercharge an R8V10, well you need to drive one first, then come back with your opinion on it. I've tracked mine this year with no failures.

And your claim that MTM's SC kit is slower than OEM is just laughable stuff.
 

·
Registered
Joined
·
47 Posts
We didn't find the need to change anything. The fueling system has plenty of headroom. We've also tested other Audi platforms on E85 for several years straight and have found no need to change fuel lines.
I'm also interested in how much head room is built into the stock fuel system.

The twin turbo GTO in my signature puts down 830hp and 840 ft-lbs to the tire. I have twin 240 pumps in the tank with 60lb injectors running about 90% duty cycle, with a methanol injection system on 93 octane. If I change the car over to E85 I looking at 85lb injectors and 340 pumps at a minimum. I shift this car around 6300, with a red line of 6500 rpm. I'm a little skeptical that Audi would have that much head room in their fuel system to switch to E85 with just software. I would like to know what injector duty cycle it takes to get the motor to 9,000 rpm on E85. Anything over 80% is asking for trouble. I say this knowing I'm pushing mine to 90%.

I also admit this is my first exotic, so I might just be ignorant to the exotic ways. But motors are air pumps, they all run on air and fuel. They also take a certain amount of both to make X amount of power exotic or domestic.

Don't take my post as an attack. Just trying to curb my curiosity.

Thanks, Mike
 

·
Vendor
Joined
·
511 Posts
Discussion Starter #27
I'm a little skeptical that Audi would have that much head room in their fuel system to switch to E85 with just software. I would like to know what injector duty cycle it takes to get the motor to 9,000 rpm on E85. Anything over 80% is asking for trouble. I say this knowing I'm pushing mine to 90%.
Direct injection injectors don't operate on a duty cycle like the traditional port injectors. The amount of time they spray is less than total injection window, even at 9,000 RPM.
 

·
Registered
Joined
·
47 Posts
Direct injection injectors don't operate on a duty cycle like the traditional port injectors. The amount of time they spray is less than total injection window, even at 9,000 RPM.
Interesting. Thank you

Mike
 

·
Registered
Joined
·
329 Posts
It's available for 91, 93 and E85 fuel grades and offers up to 650 HP with 435 FTLBS and a new 9,000 RPM limiter in manual mode.
I was looking at your dyno charts. It appears that that your 91/93 tunes peak at approximately 8,000 rpms and trail off from there. For example:



It appears that only your E85 tune continues to build power until 9000 rpms. Therefore, while the the 9000 rev limiter is likely advantageous for the E85 tune, is there a benefit with your 91 and 93 tunes?
 

·
Vendor
Joined
·
511 Posts
Discussion Starter #30
Therefore, while the the 9000 rev limiter is likely advantageous for the E85 tune, is there a benefit with your 91 and 93 tunes?
It's still advantageous. HP alone from the graph doesn't pain the correct story. What you need to plot is axle torque for each gear. Your ideal shift point will be the highest point in which the next gear's axle torque is the highest. I believe that point comes after 9,000 RPM, but we were not comfortable continuing to rev higher.
 

·
Registered
Joined
·
119 Posts
It's still advantageous. HP alone from the graph doesn't pain the correct story. What you need to plot is axle torque for each gear. Your ideal shift point will be the highest point in which the next gear's axle torque is the highest. I believe that point comes after 9,000 RPM, but we were not comfortable continuing to rev higher.
Thread revival

Now that it has been a couple of years since this post, I imagine you have quite a few of these parading around

Have any of the customers had any failures relating to the increased redline?

Thanks
 

·
Registered
Joined
·
732 Posts
funny. i never saw this post. fwiw- i believe the AMAX setting = performance dry? the fact that in performance dry my car just pulls and pulls and pulls with no loss in power is unique to that setting. i just walked an 700 hp GTR on the hway last weekend in that setting.
 

·
Registered
Joined
·
136 Posts
Thread revival

Now that it has been a couple of years since this post, I imagine you have quite a few of these parading around

Have any of the customers had any failures relating to the increased redline?

Thanks
Sorry but do you really think they'd actually tell you if there was?
 

·
Registered
Joined
·
83 Posts
It's still advantageous. HP alone from the graph doesn't pain the correct story. What you need to plot is axle torque for each gear. Your ideal shift point will be the highest point in which the next gear's axle torque is the highest. I believe that point comes after 9,000 RPM, but we were not comfortable continuing to rev higher.
Very interesting how power still climbs till limit with ethanol. What would be first "bottlenecks" if going past 9000 rpm?
 

·
Registered
Joined
·
3,557 Posts
Very interesting how power still climbs till limit with ethanol. What would be first "bottlenecks" if going past 9000 rpm?
I would imagine the valve gear.
 
21 - 38 of 38 Posts
Top