[quote=“littleredwagen”]
I’ll be honest I don’t have any experience previously with E85 on other cars so it will be new to me… I’ve read up on it and been assured the only thing needing upgraded is the hpfp so we’ll see what happens… Are there specifics things you’d like me to log? Let me know…
the FSI cars get massive injectors. The B7 RS4 is a 420 hp car…and we’ve seen 600-650 hp RS4s still running stock injectors.
N54’s also use port injection to get around that. Might work out here?
[quote=“primetime,post:441,topic:4077”]
I am not sure if the ecu monitors the low pressure pump Duty Cycle, but i’d like to see that, injector duty cycle and high pressure feeds if available. I Haven’t used E85 at all myself but am curious because of its increased fuel demands
[quote=“littleredwagen,post:439,topic:4077”]
I’ll be honest I don’t have any experience previously with E85 on other cars so it will be new to me… I’ve read up on it and been assured the only thing needing upgraded is the hpfp so we’ll see what happens… Are there specifics things you’d like me to log? Let me know…
yeah but they run pump gasoline or race gasoline, which either contains more energy that the same equal volume of E85, with E85 its Volume of Fuel not quantity like pump vs race. Hence my curiosity
I know the article is old but it talks about the differences of gasoline and E85
http://www.hotrod.com/how-to/engine/hrdp-0801-e85-ethanol-alternative-fuel/
I get it. Just saying that the FSI injectors (especially on S/RS cars) traditionally have massive upside and are heavily overengineered.
E85 requires about 30% more fuel, not 100% more. So it’s quite possible the stock injectors are just fine. Of course when you take a stock B8 S4 and move it to stage 2 or stage 2+, you’re using a boatload more fuel. The car is going from making 360 hp to 450 hp or thereabouts. So you’re using lots of upside. I would submit that there is still plenty. The stage 3 kits are using stock injectors. Of course they’re making less power than stage 1 so far so not a great argument there lol
We can’t forget that the stock tune is hella rich compared to the AFR most tuners will adopt for making power on good fuel so there’s already upside there…then the overengineering part of it with lots of headroom on top of that. Who knows. We’ve seen more surprising things. The JHM B7 RS4 is a good case study. The RS4 traps 107-108 MPH stock. They were trapping 130-131 MPH. They’ve added probably 225 hp over stock. No problem. That’s a crazy amount more fuel.
the FSI cars get massive injectors. The B7 RS4 is a 420 hp car…and we’ve seen 600-650 hp RS4s still running stock injectors.
N54’s also use port injection to get around that. Might work out here?
[quote=“primetime”]
I am not sure if the ecu monitors the low pressure pump Duty Cycle, but i’d like to see that, injector duty cycle and high pressure feeds if available. I Haven’t used E85 at all myself but am curious because of its increased fuel demands
yeah but they run pump gasoline or race gasoline, which either contains more energy that the same equal volume of E85, with E85 its Volume of Fuel not quantity like pump vs race. Hence my curiosity
I know the article is old but it talks about the differences of gasoline and E85
http://www.hotrod.com/how-to/engine/hrdp-0801-e85-ethanol-alternative-fuel/
I get it. Just saying that the FSI injectors (especially on S/RS cars) traditionally have massive upside and are heavily overengineered.
E85 requires about 30% more fuel, not 100% more. So it’s quite possible the stock injectors are just fine. Of course when you take a stock B8 S4 and move it to stage 2 or stage 2+, you’re using a boatload more fuel. The car is going from making 360 hp to 450 hp or thereabouts. So you’re using lots of upside. I would submit that there is still plenty. The stage 3 kits are using stock injectors. Of course they’re making less power than stage 1 so far so not a great argument there lol
We can’t forget that the stock tune is hella rich compared to the AFR most tuners will adopt for making power on good fuel so there’s already upside there…then the overengineering part of it with lots of headroom on top of that. Who knows. We’ve seen more surprising things. The JHM B7 RS4 is a good case study. The RS4 traps 107-108 MPH stock. They were trapping 130-131 MPH. They’ve added probably 225 hp over stock. No problem. That’s a crazy amount more fuel.
yeah it is about 25-30% more required with E85. We will see will be interesting for sure. Not sure what the point would be running E85 and using more fuel for like 10-30hp more depending on the actual quality of the E85 fuel.
[quote=“littleredwagen,post:455,topic:4077”]
I’m hoping to quantify in terms of tenths of a second at the strip not HP ;D
Oh and still no time from our friends at Solo Motorsports… Shocking…
[quote=“primetime,post:456,topic:4077”]
help me understand AFR and E85 vs. race gas
if you have a fixed amount of air (maxed out 2 pulley TVSr1320)…now your fuel is the variable.
What’s the difference between race gas and E85?
i.e. is there any reason to run E85 over 93+meth or over 110 race fuel (and being tuned for each of course)
Is there really a performance delta with E85 vs. race fuel?
Feels like the limiting factor is the blower, so I don’t see the point of the E85 as my limited experience has been that the race fuels accompish much of what E85 does. Only real beit is the availability of E85 at gas stations in certain regions (not that I’ve ever seen it in Florida, California, Michigan). is it a money thing? i.e. you can accomplish the same performance for less money? If you’re upgrading fuel pumps, and paying for 20-30% more fuel for the same work, there goes a lot of cost savings
So…what’s the point?
E85, the way I’ve always seen it…is a cheap alternative to making race gas power…nothing more. In places where it’s available everywhere, it makes some sense…but I’ve yet to see one person who hasn’t had headaches dealing with a full-on E85 converted car.
I don’t think E85 will be a world of a differnce for a guy like Prime who has never ran anything but race gas…for him to convert it just doesn’t make a ton of sense. Maybe he just wants to fill up at a pump instead of from a can all the time, because I’m 100% sure the cost savings has nothing to do with his choice.
E85 should burn cooler and keep in-cylinder post combustion temperatures lower. Not sure if we can directly verify this, as the MAP/IAT sensor is in the manifold. But we’ve seen timing retard even with the race gas on the record passes. If we aren’t at MBT, then there is still performance room. Should be worse once stg 2+ boost levels are fully realized. So it’s possible in cylinder temps are helping to create knock onset.
I think he fills up at a pump near his house (race gas). He also likes making changes and being first. Some people do. The TCU tune is a great example. A perfectly working transmission and a launch method that nobody has been able to beat…and primetime still switched to the APR TCU. Since doing so, his car hasn’t run right (nor has anyone’s car from the sounds of it) a year later. The two fastest APR B8 S4s are Primetime and Rynurz at 11.50 and 11.56…and they’re both either slipping shifts, hanging up, and short shifting, or some combo therein.