OFT Review (Vishnu Tuning Tablet first impressions)

[steve99]

Originally Posted by Fresh86

Hey I have a question? I just purchased mine a few days ago and Here where I live we don't have 93 octane ... we have 91 or 94...could i use 94 on the 93 tune and be fine?

for a tune designed for 93 octane obviously 93 would be fine

94 would be best as it has more knock resistance hence ECU will run full timing advance and produce best power, won't produce any more power as tune will produce this on 93 (assuming no knock encounter on 93, IAM should be =1 on 93 or 94.

91 will work but ECU will likely detect knock, reduce timing advance (IAM less than 1) thus reducing power. Won't damage anything but you will not get the maximum benefit from the tune.


even the factory tune is designed for 93 for max power, will run on 91 but at reduced power due knock retard IAM less than 1 in most cases.

IAM = Ignition advance multiplier can be monitored on OFT or other logging device if its less than 1 indicates knock encounted and ignition timing has been retarded by ECU (ie advance reduced) to compensate for lower octane fuel.

[bfrank1972]

Originally Posted by steve99

for a tune designed for 93 octane obviously 93 would be fine

94 would be best as it has more knock resistance hence ECU will run full timing advance and produce best power, won't produce any more power as tune will produce this on 93 (assuming no knock encounter on 93, IAM should be =1 on 93 or 94.

91 will work but ECU will likely detect knock, reduce timing advance (IAM less than 1) thus reducing power. Won't damage anything but you will not get the maximum benefit from the tune.


even the factory tune is designed for 93 for max power, will run on 91 but at reduced power due knock retard IAM less than 1 in most cases.

IAM = Ignition advance multiplier can be monitored on OFT or other logging device if its less than 1 indicates knock encounted and ignition timing has been retarded by ECU (ie advance reduced) to compensate for lower octane fuel.

I was under the impression the OTS stage 1 tune was actually optimized for 91, not 93. Might actually be able to squeeze a little more out of 94 fuel.

Also regarding the OTS E85 tune, is there room for more timing advance for true E85? @shiv@vishnu says anything greater than E60 is fine, just wondering if he built in a large safety margin or if its that you just can't benefit from any further timing advance.

Sent from my QMV7A using Tapatalk

[JdelFrs]

My only concern about open tune & OFT is in the long terms! We dont have much review of car using the tune for more than 10k miles :o. i am waiting for those review :o before making my choice!

[Sniper2606]

Originally Posted by JdelFrs

My only concern about open tune & OFT is in the long terms! We dont have much review of car using the tune for more than 10k miles :o. i am waiting for those review :o before making my choice!

I been running my Vortech SC kit with a very aggressive tune on 91 gas for 8k miles everything runs perfect, no oil cooler either, this FA20 motor seems to handle w/e u can throw at it. Just ask the Crawford performance.

[Shiv@Openflash]

Originally Posted by bfrank1972

I was under the impression the OTS stage 1 tune was actually optimized for 91, not 93. Might actually be able to squeeze a little more out of 94 fuel.

Also regarding the OTS E85 tune, is there room for more timing advance for true E85? @shiv@vishnu says anything greater than E60 is fine, just wondering if he built in a large safety margin or if its that you just can't benefit from any further timing advance.

Sent from my QMV7A using Tapatalk

Our OTS maps have been calibrated for 91-93oct. We leave a little bit on the table for 93oct folks. 91oct folks (such as myself) also operate conservatively but may see some KR from time to time in very warm conditions. But Adv Multiplier should stay at 1 (or close to it) most of the time.

With E85, you will achieve all the knock resistance you can need with just E60. At that E% you have enough octane to run max timing for best torque. No sense in running more advance because you will actually start to lose power (even without the presence of knock). So going to E85 is, in many ways, overkill. It's just more convenient since you can just fill 'er up instead of mixing fuel carefully.

Cheers,
Shiv

[bfrank1972]

Originally Posted by shiv@vishnu

Our OTS maps have been calibrated for 91-93oct. We leave a little bit on the table for 93oct folks. 91oct folks (such as myself) also operate conservatively but may see some KR from time to time in very warm conditions. But Adv Multiplier should stay at 1 (or close to it) most of the time.

With E85, you will achieve all the knock resistance you can need with just E60. At that E% you have enough octane to run max timing for best torque. No sense in running more advance because you will actually start to lose power (even without the presence of knock). So going to E85 is, in many ways, overkill. It's just more convenient since you can just fill 'er up instead of mixing fuel carefully.

Cheers,
Shiv

Thanks Shiv for clarifying that!

BTW I had a service last weekend, so I put it back to the stock map. Man, you can really feel the difference - the stock tune is just crap compared to the OFT stage 1 map. Power wise there certainly is a noticeable difference... but as everyone else has mentioned, the important difference that no dyno will illustrate is the *big* improvement in responsiveness and driveability! Idles smooth as silk. In traffic there is no more jerkiness when rolling with clutch out, even in 1st. Throttle response is much more eager, reminds me of my old MFI 911. Torque dip really isn't noticeable anymore, or at least not the pest it once was. Just improves the driving experience in many ways - and it is really apparent when you have yo revert to the stock map. It is like the car is running on bad gas. Anyway I'm impressed.

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[Shiv@Openflash]

Originally Posted by bfrank1972

Thanks Shiv for clarifying that!

BTW I had a service last weekend, so I put it back to the stock map. Man, you can really feel the difference - the stock tune is just crap compared to the OFT stage 1 map. Power wise there certainly is a noticeable difference... but as everyone else has mentioned, the important difference that no dyno will illustrate is the *big* improvement in responsiveness and driveability! Idles smooth as silk. In traffic there is no more jerkiness when rolling with clutch out, even in 1st. Throttle response is much more eager, reminds me of my old MFI 911. Torque dip really isn't noticeable anymore, or at least not the pest it once was. Just improves the driving experience in many ways - and it is really apparent when you have yo revert to the stock map. It is like the car is running on bad gas. Anyway I'm impressed.

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That's what we like to hear!

[uncivilised]

I assume there are a few guys in australia using shiv's e85 tune. You guys using united 85 or other e85 sources?

[steve99]

Originally Posted by bfrank1972

I was under the impression the OTS stage 1 tune was actually optimized for 91, not 93. Might actually be able to squeeze a little more out of 94 fuel.

Also regarding the OTS E85 tune, is there room for more timing advance for true E85? @shiv@vishnu says anything greater than E60 is fine, just wondering if he built in a large safety margin or if its that you just can't benefit from any further timing advance.

Sent from my QMV7A using Tapatalk

Hi,

If you have a look at the release notes for the tunes its says petrol tunes optimized for 93 AKI (american) fuel so the tune will run its maximum advance on 93, hence running 94 or higher octane will not get you any more power.

Octane is a rating of the fuel's resistance to knock/detonation not a measure of the energy content of the fuel.

E85 has a greater octane rating than straight petrol but actually less energy value per liter due the ethanol content hence you have to use more to produce the same energy at petrol. so fuel economy is less. aprox 25-30%

However you can run much more ignition advance due to the higher octane rating and I believe it burns cooler than petrol.

Shiv said somewhere that even E60 has enough octane rating to run the full advance with no knock and that that was about as much octane as a N/A motor with 12.5/1 compression needed. different if its boosted as effective compression ratio increases under boost and better octane rating needed. So for N/A it would appear it already running close to the max timing possible for this motor and nothing much left to improve.

His tunes adjust fueling using ltft to account for the different fuel density's between the range of E60 to E90 but the timing remains the same. ( (@jamesm blood pressure rising already)

Although with a true flex fuel kit (sensors wired into ECU) you could probably reduce safety margins and get better fueling compensation so I would imagine you could squeeze a bit more out of it.

Note I am not a tuner just done a bit of reading

anyhow shiv beat me :-)

[steve99]

Originally Posted by uncivilised

I assume there are a few guys in australia using shiv's e85 tune. You guys using united 85 or other e85 sources?

Hi,

Yes used united aparantly is pretty consistent at E85- E90 where as the Caltex E-flex stuff varies in alcohol content E65-E85. Probably not a drama for N/A guys but the boosted guys prefer the higher and more consistent United fuel

[Captain Insano]

Took a log today after a couple hundred miles of learning on stg1 with 93 octane fuel... This is on v1.42 still, seems like logs are OK. Car feels absolutely beastly - very badass at just stg1. Thinking about switching to v1.55b tomorrow.
http://www.datazap.me/u/captain-insa...&data=1-8-9-12

[Shiv@Openflash]

Originally Posted by Captain Insano

Took a log today after a couple hundred miles of learning on stg1 with 93 octane fuel... This is on v1.42 still, seems like logs are OK. Car feels absolutely beastly - very badass at just stg1. Thinking about switching to v1.55b tomorrow.
http://www.datazap.me/u/captain-insa...&data=1-8-9-12

You will like the new maps a whole lot more.

[Captain Insano]

Cool... uploaded v1.55b to my OFT tonight so I am ready to flash stg1 in the morning before work.

[Sirsimon]

Ordered my OFT today. Very, very excited. Thanks Shiv for all the work you've put into this car. :-)