Nissan GT-R Forum banner
1 - 13 of 13 Posts

·
Sophisticated
Joined
·
2,980 Posts
So I ran a test. I put 3 gallons of E85 in my tank and then I topped it off with 93. I have only a tune and midpipe on my 2013.

I ran some data logs to see how my fuel trims were taking the extra E85 in the tank.

Honestly the trims looked exactly the same. The car runs strong with zero knock. Here is a 4th gear log. View attachment e23-.csv

I'm not going to make my tune more aggressive though. I'll try E25 again the next time I hit the drag strip to see if my trap improves. I usually see some knock on shifts at the drag strip since my car runs LC5 natively. LC5 doesn't pull timing on the shifts like LC4 does.

Here is the thread that gave me the courage to do it.
http://www.gtrlife.c...low-boost-mode/
 

Attachments

·
Registered
Joined
·
311 Posts
Low boost usually kicks in when you're running crappy gas like us out here in Cali. we add race gas or a bit of e85 to increase octane. If you're on 93, no need on standard tune
 

·
Super Moderator
Joined
·
8,950 Posts
So I ran a test. I put 3 gallons of E85 in my tank and then I topped it off with 93. I have only a tune and midpipe on my 2013.

I ran some data logs to see how my fuel trims were taking the extra E85 in the tank.

Honestly the trims looked exactly the same. The car runs strong with zero knock.

I'm not going to make my tune more aggressive though. I'll try E23 again the next time I hit the drag strip to see if my trap improves. I usually see some knock on shifts at the drag strip since my car runs LC5 natively. LC5 doesn't pull timing on the shifts like LC4 does.

Here is the thread that gave me the courage to do it.
http://www.gtrlife.c...low-boost-mode/
Is the base fuel 93e10 or 93e0?
 

·
Registered
Joined
·
301 Posts
Any car will be most prone to detonate during a long pull in hot, dry weather. Certainly the 3 gallons of e85 are going to help you if you ever race under those conditions.
 

·
Sophisticated
Joined
·
2,980 Posts
Discussion Starter · #7 ·
Any car will be most prone to detonate during a long pull in hot, dry weather. Certainly the 3 gallons of e85 are going to help you if you ever race under those conditions.
Agreed. Yinger must not push his car or his tune as hard as some. ;)
 

·
Warrant Officer
Joined
·
700 Posts
To be clear, your car is stock aside from a midpipe and a 93 octane tune? I'm not trying to flame, I'm having a hard time understanding your first post; are you saying the extra E85 helped or that there was no verifiable difference? Would you normally get a bit of knock without the extra E85?

Also, I enjoy reading your threads. You always seem extremely objective when testing/hypothesizing/etc.
 

·
Sophisticated
Joined
·
2,980 Posts
Discussion Starter · #10 ·
Hi Mark, I was basically testing to see if the fuel system could handle extra E85 in the tank. Using 2-4 gallons of E85 per fill up only increases the fuel requirement between 1.5% to 4% so it should be fine for GT-R owners to run that amount with the stock fuel system. I wanted to test it in real life.

An aggressively tuned FBO car with an already overtaxed fuel system might have issues though.

Yes, my car has a tune and midpipe. It doesn't knock on the street but at the drag strip it does. I'm going to test out the E25 and see if the knock goes away. I bet it does.

Its really strange how it only knocks at the drag strip. I can do a full 1/4 mile run on the street with zero knock but when I'm at the track, it can knock quite a bit. I think it has to do with the aggressive sticky launch and the fact LC5 doesn't pull timing on the shifts.
 

·
Super Moderator
Joined
·
8,950 Posts
Hi Mark, I was basically testing to see if the fuel system could handle extra E85 in the tank. Using 2-4 gallons of E85 per fill up only increases the fuel requirement between 1.5% to 4% so it should be fine for GT-R owners to run that amount with the stock fuel system. I wanted to test it in real life.

An aggressively tuned FBO car with an already overtaxed fuel system might have issues though.

Yes, my car has a tune and midpipe. It doesn't knock on the street but at the drag strip it does. I'm going to test out the E25 and see if the knock goes away. I bet it does.

Its really strange how it only knocks at the drag strip. I can do a full 1/4 mile run on the street with zero knock but when I'm at the track, it can knock quite a bit. I think it has to do with the aggressive sticky launch and the fact LC5 doesn't pull timing on the shifts.
Have you tried LC4 at the drag strip yet?
 

·
Sophisticated
Joined
·
2,980 Posts
Discussion Starter · #12 ·
Have you tried LC4 at the drag strip yet?
I haven't flashed my trans in this car yet. It still has the 100% stock factory tune in it. I might flash it to LC4 for some back to back test's soon but I'm fighting with the idea. It's nice to have my factory TCM tune unmolested.
 
1 - 13 of 13 Posts
Top