Regular vs. Super unleaded petrol.....

[Woodsy99]

My 16K mile 2007 LS2 engined Vette (manual box) has Kooks long tube ceramic headers, sports cats and Borla Attak mufflers plus an Airaid performance intake.
Due to these upgrades the check engine light comes on and I'm booked in the have this dealt with at the same time as having the engine performance optimised by a company called Wortec, who can get into the ECU using HP software
These engines normally run on regular unleaded - has anyone got experience of benefits when switching to super unleaded e.g. improved MPG or performance?
Any views/input would be welcome
Thanks, Nick

 

[Chevrolet]

TBH - In your case, think that's a question best answered by Wortec isn't it?

 

[Woodsy99]

I just wanted to see if anyone had previously gone through this exercise and had any views on the subject

 

[craigyboy]

Wortec should tune the engine to the fuel you are going to daily use. Are Wortec putting the car on a rolling road and doing a tune that way?

 

[Woodsy99]

Wortec have done the ECU tuning and the result was 452 bhp & 467 lb ft torque. The tuning was done with a full tank of super unleaded which I will be only using in future.
Watch out for the article in the August Vette new.........

 

[craigyboy]

Interesting figures they gave you. They have remapped a 2005 bog standard C6 and Wortec said 465 BHP. You have more stuff done and have less BHP. Something not right there

 

[Custom exotics]

Prob wheel hp not engine so allowing at least 10% if this is case but worth asking that question

 

[craigyboy]

you would expect Wortec who tuned both cars would tell the customer the HP in the same way

 

[Custom exotics]

And a stock c6 ls2 powered vette is only 400hp from factory so marked improvement I would say

 

[Daytona Vette]

Regardless of component degradation and fuel Temp, the percentage of ethanol in the Fuel mix may well be an important factor

 

[teamzr1]

If your country as here in the USA where the gas used has E10 or E15 percent of Ethanol
Ethanol is lousy, as it reduces fuel mileage and causes the AFR (fuel trims) to be lean from 7-10%
That then causes more engine ping/knock so the PCM yanks out timing which reduces torque/HP
The engine then has to recover from that so overall performance is lost

Here in the USA as my business I have been doing custom performance tuning since 1995
I have seen countless GM vehicles with ill performance due to use of Ethanol and lower octane gas

Most here in the USA with like Corvettes, Caddy, Camaro, etc are willing to pay more at the pumps for gas that
has no Ethanol at all

This allows then since there will be chance of ping via a PCM tune to dial in more timing and gain in performance
Or at the least tuning the PCM in use of E10 or E15 to command the fuel injectors so that the AFR is richer and
adjust timing tables to reduce that ping.

Once tuned then try and stay with that octane of gas or if using less with that tune expect the PCM to react to ping and yanking timing out

I assume when using BHP you mean Brake HP, but that is engine alone with nothing attached to it (like on an engine dyno)
If that is what you're using to gauge performance number then what you listed would be lower than GM uses when engine is in vehicle

Find out how the shop got those numbers either using a load or non bearing dyno reports rearwheel HP/Tq
or using a OBD-II scanner obtained what the PCM calculates as it has a built in dyno used for torque management which is at flywheel