MeltedSolid
Autocross Newbie
- Location
- San Francisco Bay Area
- Car(s)
- '15 Golf, e36 328i
I don’t think a turbo and a tune is going to net you 100HP... certainly not on 87.
Arent... you doing that right now?... not 87, but still?...
I don’t think a turbo and a tune is going to net you 100HP... certainly not on 87.
to add one point though, i do not recommend using 87 + e85 as an excuse to get a 91 or 93 tune. While you could technically do this, its not a safe way to go as e85 varies on octane rating (can be as low as 94, or up to 105), and you will need to make sure to put enough in to boost fuel all the way past 91-93. So if the batch you are putting in is 94-96 range, you would need way more than the safe amount for our cars. I only recommend using a bit of e85 to give you some more wiggle room on pre ignition conditions using the 87 on an 87 tune.
Arent... you doing that right now?... not 87, but still?...
to add one point though, i do not recommend using 87 + e85 as an excuse to get a 91 or 93 tune. While you could technically do this, its not a safe way to go as e85 varies on octane rating (can be as low as 94, or up to 105), and you will need to make sure to put enough in to boost fuel all the way past 91-93. So if the batch you are putting in is 94-96 range, you would need way more than the safe amount for our cars. I only recommend using a bit of e85 to give you some more wiggle room on pre ignition conditions using the 87 on an 87 tune.
Agreed that ethanol dosing is NOT the safe way to get past 87 octane. Looking at some literature on LSPI, there's evidence that suggests e20-e30 blends are critically NOT the solution for prevention. In fact, quite the opposite, suggesting these blends result in more LSPI events while NOT mitigating mega-knock (the engine killer) when compared to higher or lower blends.
reference: https://www.thefreelibrary.com/Infl...s+on+Low+Speed+Pre-Ignition+in...-a0528616644
okay so I read several claims here about LSPI and octane. Can you please back them up with authority?
can anyone point to evidence that APR's 87 tune is riskier than say, the stock tune on a 1.8t?
Most of what I've found so far seems to point to oil.
I get the idea that some prefer to be cautious given the possible severity of loss.
But given all this hand wringing, why would anyone tune on any octane level?
APR 87 tune is certainly riskier than stock cars. Its running more boost, which means higher compression ratios, and can increase likely hood of pre ignition or knock. No one here was really suggesting that its a liability, it was more of a comment that APR a) is in it to make money, and advertising more power will entice people, and b) that the 87 tune may not be as safe. APRs main business is tuning for 91 fuels and up, and that is where most of their research and time goes. The 87 tune likely did not get the attention that other fuels did, and may have just been released as an option while running 1psi less without doing as much testing. I have not seen what Arin said about the 87 tune, but if is true that he says he wouldn't run it, that is pretty telling since it is coming from an APR employee.
Sorry to play the complete devil's advocate, but APR plus uses their 87 octane tune, and they're still expecting you to use 87 with that. If they weren't confident in the safety of that tune, why are they willing to warranty it? It's not the IS20 tune, but still, it's the same process to tune a car for any octane, be it 80 or 110 so I wouldn't be worried about the safety of a particular tune based on what octane it's supposed to be rated for. The only thing I'd really be worried about is the quality of the 87 octane fuel itself, but just don't go to a sketchy gas station.