[mcqueen]

Alright, we all talk about how great our 93 octane tunes are, but have any of you guys ever reverted back to 87 just to see the difference in power?

I'm slowly getting my car ready to be sold and yesterday I switched the tune back to 87 so that when I trade it off, the next owner doesn't fuck up the engine by running a lower octane. Had a half tank of 93 left, filled up the rest with 89 octane (from a cheaper station). To be honest, I didn't feel a difference in power. The only thing I've noticed is that I burn through this cheap gas faster.

I'm sure there are some gains from the 93 tune on paper, but I'm starting to think we're giving a simple timing increase too much credit for what we feel when we drive our cars.

Your thoughts?

[v6kid]

I haven't tried reverting to a lower octane tune, but I see what you are saying. It's most likely a half real and half mental thing in the new edges.

[mcqueen]

Yeah I should have mentioned new edge (probably SN95 as well). I hear the S197s see bigger gains than us.

[rfcsoulja]

Really you won't feel a drastic change with 5-7 hp. I haven't really heard anyone state a 93 octane tune producing more than that on out vehicles.

[i-bought-a-v6]

and some people say you need a cai or a windstar to get more gains

[mustangmike!]

Originally Posted by mcqueen Alright, we all talk about how great our 93 octane tunes are, but have any of you guys ever reverted back to 87 just to see the difference in power? I'm slowly getting my car ready to be sold and yesterday I switched the tune back to 87 so that when I trade it off, the next owner doesn't fuck up the engine by running a lower octane. Had a half tank of 93 left, filled up the rest with 89 octane (from a cheaper station). To be honest, I didn't feel a difference in power. The only thing I've noticed is that I burn through this cheap gas faster. I'm sure there are some gains from the 93 tune on paper, but I'm starting to think we're giving a simple timing increase too much credit for what we feel when we drive our cars. Your thoughts?

Your comment about the cheaper gas ...
Thats where this will probably have its most gains.
Maybe not such a power increase, but more effiecient and cleaner fuel. 93 should be better for your engine, and the "power increase" may be coming as better gas milage. More power using the same fuel means you can use less fuel to do the same thing.

What im saying if that doesnt make sense is this:

87 = 18mpg
93 = 21mpg

(these numbers were pulled out of my ass)

[mustangmike!]

Originally Posted by i-bought-a-v6 and some people say you need a cai or a windstar to get more gains

Just about anything that increases the amount of air going into your engine, or quality of air, will increase performance.

Really, CAI kits are a waste of money in our cars. They just make it sound better. Or thats what reviews have showed me.

A windstar WILL give more performance from its design

[walt1120]

Originally Posted by mcqueen Alright, we all talk about how great our 93 octane tunes are, but have any of you guys ever reverted back to 87 just to see the difference in power? I'm slowly getting my car ready to be sold and yesterday I switched the tune back to 87 so that when I trade it off, the next owner doesn't fuck up the engine by running a lower octane. Had a half tank of 93 left, filled up the rest with 89 octane (from a cheaper station). To be honest, I didn't feel a difference in power. The only thing I've noticed is that I burn through this cheap gas faster. I'm sure there are some gains from the 93 tune on paper, but I'm starting to think we're giving a simple timing increase too much credit for what we feel when we drive our cars. Your thoughts?

Your going to gain like 5hp with a 93 over 87 on OUR motors. the 3.8 runs a lower compression than both the 4.0 and the 4.6. and because of that our engine really doesn't need 93 octane or anything higher than 87 for that matter. there are different factors but generally displacement + compression is going to tell you how much of a difference a 93 tune will make on a stock N/A motor.

our stock engines just simply don't need 93 octane fuel, i would personally only run a 93 tune of i had some internal work done.

[mustangboy99]

hey guys i drive daily on a 89 tune and track a 93 tune.. but honestly i feel no difference besides shift points and rev limiter..
but i have exhaust and CAI tune with pulleys.. and the high the tune the worse gas mileage i get

[walt1120]

Originally Posted by mustangboy99 hey guys i drive daily on a 89 tune and track a 93 tune.. but honestly i feel no difference besides shift points and rev limiter.. but i have exhaust and CAI tune with pulleys.. and the high the tune the worse gas mileage i get

well with bama tunes from AM, the higher the octane the more aggressive they make the tune. that's why the 87 octane is called the street tune and the 93 is the race tune. 89 is fine for daily driving.

[xn1919]

93=wiplash

[04mustang232]

I switch back and forth alot actually, ill usually go 4 tanks of 87 then a tank of 93...i can definately feel a difference, and my car actually sounds different. If i didn't feel a difference, id leave it on 87 to save $

[mcqueen]

Originally Posted by walt1120 well with bama tunes from AM, the higher the octane the more aggressive they make the tune. that's why the 87 octane is called the street tune and the 93 is the race tune. 89 is fine for daily driving.

I have an 87, 89, and 93 octane from Bama and didn't feel any difference or hear any difference in the exhaust when I switch back to the 87 after having run the 93 for most of the year. My car still pulls just as hard on the 87 tune as it did on the 93 tune. I might run this tank low and go back to the 93 just to see if I can get a difference, but I'm starting to think anything I felt originally was all in my head. I know the gains are there on paper, but I remember how awesome it felt when I got my 93 tune running well and when I recently dropped back to 87 it didn't feel any different than how the car has been running for months.

I'm at a half tank right now, I'll fill it up with 93 soon and give it another test. I might change the spark plugs as well. I'm getting some detonation at higher RPMs with my NGK's that only have 8k miles on them.

Originally Posted by xn1919 93=wiplash

Originally Posted by 04mustang232 I switch back and forth alot actually, ill usually go 4 tanks of 87 then a tank of 93...i can definately feel a difference, and my car actually sounds different. If i didn't feel a difference, id leave it on 87 to save $

Do you switch the tune each time? I had detonation so badly when I first switched to 93 (from the little bit of 89 left in the bottom of the tank) that I couldn't get the car up to 3k RPM. I ran the 93 tune for 8 months or so after that and didn't switch back because of that?

[Tang Stang]

I ran a Splitport 3.8L V6 from a '00 Mustang in my old daily driver (1994 Tbird LX) for years with an early Diablo switch chip. The difference between the 87 octane tune and the 93 octane tune (as tuned by me, on the same dyno, though on two different days) was 8 rwhp and 12 rwtq. The difference was barely noticeable on the street.

[walt1120]

Originally Posted by Tang Stang I ran a Splitport 3.8L V6 from a '00 Mustang in my old daily driver (1994 Tbird LX) for years with an early Diablo switch chip. The difference between the 87 octane tune and the 93 octane tune (as tuned by me, on the same dyno, though on two different days) was 8 rwhp and 12 rwtq. The difference was barely noticeable on the street.

thats good, seems to confirm what everyones saying with some real numbers.

on a different higher compression motor the results might be a lot more significant but on a 3.8, you just really dont need to waste your money on 93.

the AM bama tunes seem to make the shifts harder with the 93 tune just because its the "race tune", i set my shift firmness as high as i can on 87 and it shifts just as hard. no sense to waste money on 93 on a stock 3.8 IMO

[mcqueen]

Originally Posted by walt1120 the AM bama tunes seem to make the shifts harder with the 93 tune just because its the "race tune", i set my shift firmness as high as i can on 87 and it shifts just as hard. no sense to waste money on 93 on a stock 3.8 IMO

My shift firmness depends on how hard I think I can slam the shifter in the next gear without breaking it

[walt1120]

Originally Posted by mcqueen My shift firmness depends on how hard I think I can slam the shifter in the next gear without breaking it

im talking about the cool kids with autos here

yeah now i can definitely see how you wouldnt feel a difference between the 93 89 87.

[Codeman]

Every little bit adds up in my opinion. Is it worth it on a car that does not need it? No I would not waste my money on it. I would not even waste my own money on it, but I had one tune and plan on camming it so am going to stick with 91. But for most ppl I would not spend the extra money on the gas. I ran my car two years with an 87 octane tune and had basically gears, udp, cai, exhaust. Until you get into your engine don't waste the money on the premium gas. Unless your running at the track and want every bit of performance.

Also it is hard to get the exact timing to work with premium without a dyno. Some engines like a lot of timing, while others don't. If you wanted the absolute most like one guy said you would get the timing set on a dyno. Go until you have peak power add another degree and keep on until it drops. Then use the timing value that gives you the most RWHP and RWTQ.

This is just my opinion on it all.

EDIT: And 7 rwhp equates to under .05 added in 1/4 of a mile that is why you don't feel a difference. The only difference I feel is a snappy throttle. And that I don't really think changed at all just my head playing tricks on me.

[mcqueen]

Originally Posted by Codeman Every little bit adds up in my opinion. Is it worth it on a car that does not need it? No I would not waste my money on it. I would not even waste my own money on it, but I had one tune and plan on camming it so am going to stick with 91. But for most ppl I would not spend the extra money on the gas. I ran my car two years with an 87 octane tune and had basically gears, udp, cai, exhaust. Until you get into your engine don't waste the money on the premium gas. Unless your running at the track and want every bit of performance. Also it is hard to get the exact timing to work with premium without a dyno. Some engines like a lot of timing, while others don't. If you wanted the absolute most like one guy said you would get the timing set on a dyno. Go until you have peak power add another degree and keep on until it drops. Then use the timing value that gives you the most RWHP and RWTQ. This is just my opinion on it all. EDIT: And 7 rwhp equates to under .05 added in 1/4 of a mile that is why you don't feel a difference. The only difference I feel is a snappy throttle. And that I don't really think changed at all just my head playing tricks on me.

From the money standpoint between 89 and 93 octane, I'm about ready to switch back to 93 just for the mpg. On an average week I burned ~1/4 to 3/8 of a tank. Running 89 octane on the 87 octane tune I've burned over a half tank this week. When I run 93 I have to go to a place with high quality gas to get it, but with 87/89 I can get it anywhere. Part of the reason I switched back to the 87 tune was because the closest place with 93 octane is 15 minutes away, but I can drive 100 yards down the road and fill up with 89.

My car has nothing to justify a dyno tune, so it's just going to stick with the Bama tunes for now

[walt1120]

Originally Posted by mcqueen From the money standpoint between 89 and 93 octane, I'm about ready to switch back to 93 just for the mpg. On an average week I burned ~1/4 to 3/8 of a tank. Running 89 octane on the 87 octane tune I've burned over a half tank this week. When I run 93 I have to go to a place with high quality gas to get it, but with 87/89 I can get it anywhere. Part of the reason I switched back to the 87 tune was because the closest place with 93 octane is 15 minutes away, but I can drive 100 yards down the road and fill up with 89. My car has nothing to justify a dyno tune, so it's just going to stick with the Bama tunes for now

yeah but is the mpg your saving worth the price of 93?