Arrow PCM. Will it recognize race gas?

[timberwolf]

Any ideas? Just wondering if it will recognize anything above 93 octane.

Thanks,

Greg

[Jack B]

The only tangible the pcm can do relative to fuel is respond to knock sensors - therefore, no.

[timberwolf]

The only tangible the pcm can do relative to fuel is respond to knock sensors - therefore, no.

Darn it. Thanks

[mjorgensen]

Arrow has tested it with up to 100 octane and there were some minor gains up to about 95-97, but that could be car or fuel dependent, do you need more than 93? nope, but a cushion of 95 couldn't hurt on track days and high heat, you definitely don't want to over octane it though.

[timberwolf]

Arrow has tested it with up to 100 octane and there were some minor gains up to about 95-97, but that could be car or fuel dependent, do you need more than 93? nope, but a cushion of 95 couldn't hurt on track days and high heat, you definitely don't want to over octane it though.

Great info! I agree about adding some race fuel on race days to prevent any detonation. Thanks for the reply

[Jack B]

Race gas is nice insurance, however, it might cost you some hp. Most of the race fuels have a stoich lower than 93 octane fuel. This means that you could alter the ideal a/f that was programmed into the pcm. One safe way is to mix 93 octane in a ratio of 50/50 with Sunoco 260GT. With this mix, the a/f ratio will not be greatly altered. As an example If you were to use VP109, you could lose hp due to a less than acceptable a/f, this is due to a big change in the stocih.


Great info! I agree about adding some race fuel on race days to prevent any detonation. Thanks for the reply

[timberwolf]

Race gas is nice insurance, however, it might cost you some hp. Most of the race fuels have a stoich lower than 93 octane fuel. This means that you could alter the ideal a/f that was programmed into the pcm. One safe way is to mix 93 octane in a ratio of 50/50 with Sunoco 260GT. With this mix, the a/f ratio will not be greatly altered. As an example If you were to use VP109, you could lose hp due to a less than acceptable a/f, this is due to a big change in the stocih.

Jack,
Sorry for the delayed reply but I received no notification... Thank you for this tip. I will look into it. I have a roll race event July 10th, and might order some!

Regards,

Greg

[Rapidrezults]

I have been running Torco octane boost up to about 95-96 and the car feels great, even at the track. I also have VP101 that I have mixed with CA 91 octane and had no problems. Feels very powerful either way.

[timberwolf]

I have been running Torco octane boost up to about 95-96 and the car feels great, even at the track. I also have VP101 that I have mixed with CA 91 octane and had no problems. Feels very powerful either way.

I've heard that stuff leaves orange deposits on spark plugs and what not... Have you seen that?

[Rapidrezults]

I've heard that stuff leaves orange deposits on spark plugs and what not... Have you seen that?

I think if you were going to run Octane boost excessively you might see that, but I only add it when I'm going to the track or doing a little spirited driving on the street. There's a lot of debate about this and it goes both ways. Ultimately I came to the conclusion that in moderation it shouldn't hurt anything.