High Octane Fuel - Page 4 - Team-BHP

Shan2nu · 4th January 2005, 07:01

Quote:

I was told that Speed (regular) was 90 Octane & 93 was 93 (duh)!

Not sure about that, coz speed has additives and not necessarily octane boosters. I didn't find any diff in performance from Speed, but IOC Xtra Premium did wonders for my car. Now, the car pulls better from low rpms, car feels more torquey and smooth.

Shan2nu

Jaggu · 4th January 2005, 08:42

can we get some brew this weekend for the drag

speedsatya · 4th January 2005, 08:44

Speed /Power is the regular 87octane petrol with additives.
but IOC xtra Premium is 91 octane fuel.

gurdeep_s · 4th January 2005, 15:01

Octane rating of the fuel to be used in the vehicle is directly propotional to the Compression ratio. Some facts:
1. Fuel octane requirements for gasoline engines vary with the compression ratio of the engine
2. The higher an engine's compression ratio, the greater the amount of heat generated in the cylinder during the compression stroke.
3. The higher the octane rating on fuel the less volatile (evaporative qualities) and the slower the fuel burns.
4. Higher octane fuel contains more POTENTIAL energy but requires the higher heat generated by higher compression ratio engines to properly condition the fuel to RELEASE that higher potential energy.

High octane fuel does reduce knocking due to the delayed ingition. But engines with low compression ratio are not able to utilize the potential of the high octane fuel and actually the performance may reduce using high octance fuel.

Suggested Compression Ratios for Street Driven Engines
(Source: http://www.ford-trucks.com/article/i...ion_Ratio.html)
With cast iron heads, 9.0-9.3:1 is considered the maximum C/R for regular (87 octane) pump gasoline. 10.5:1 is about maximum for today’s premium (91-94 octane) pump gasoline with a cast iron head. And that’s assuming you keep the rpms up without lugging the engine, you’ve cleaned up the combustion chambers of sharp edges and rough spots to reduce the possibility of pre-ignition and use a zero deck clearance, or close to it, to enhance quench.

Aluminum heads will generally allow 11.5:1 C/R on premium pump gasoline, again assuming you have clean combustion chambers and a zero deck clearance.

If you run A/C, take .5 off the maximums.

speedsatya · 4th January 2005, 18:49

Quote:

Originally Posted by Domnic

go to the dealer and ask them to connect the OBD and interface and increase the octane type in the ecm. This will make a difference.

.

hey Dom,
now with 87 octane being replaced by 91,will it help if the octane type is changed.
can u list the cars in which this can be done.
wat abt the mpfi zen.

Domnic · 4th January 2005, 21:39

Yes,
mpfi cars will benifit from the higher octane. You can use 91 on all the indian cars, no problem whatsoever...

Cheers
Dom

speedsatya · 5th January 2005, 12:02

hey Dom ,i am talking abt changing the "octane type" in the ECM.
can u list the cars in which this setting can be changed.

anoops · 5th January 2005, 12:08

you need to check the comp ratio of your engine, any thing above 9 will work well with 91 octane gas...generally the car manual will tell you what octane rating works the best. but the fuel we get here is not the best...so 87 octane might not actually be 87....thats the only danger.

iceman91 · 10th January 2005, 12:44

well guys i used dom's mixture in my car and the response is almost immediate and the car burns better and is much more crisper...got an excellent mileage of 19.7 on the highway in my baleno...dom was sittin with me to prove it!!!

speedsatya · 10th January 2005, 13:36

wat mixture ?????????
are u talking abt the toluene.
wat was te ratio uused and with wat fuel.
how much did u get the toluene for?????????

satya

iceman91 · 10th January 2005, 13:46

dom did all for me...so u need to ask him and the mixture too is somethin he calculated according to the compression of my engine

lamborghini · 10th January 2005, 16:57

hey dom
will it be possible for you to send us some of it or like will we have to make it ourselves
anyone here sell toulene or get it ???
was thinking of using it on my palio or ikon
how much does it cost per litre ???

will there be anychange in performance of the carb if 91 octane is used .
i mean FE and performance wise
thanx

Domnic · 10th January 2005, 20:28

Hi,
No probs, let me know how much qty you guys want, or else let me know the car type, amount of mods done.... ill get it when i come to bombay.

Cheers
Dom

speedsatya · 10th January 2005, 20:53

hey lambo,
u can get it through a chemist.or u can search for one at Dava Bazaar near CST

lamborghini · 11th January 2005, 02:04

thanx for the offer dom
satya happy bday
will check it out after my exams

4th January 2005, 08:42	#47 (permalink)
Jaggu Team-BHP Moderator Join Date: May 2004 Location: Bangalore Posts: 3,633	can we get some brew this weekend for the drag __________________ The strength to change what I can, the inability to accept what I can't, and the incapacity to tell the difference. -Calvin

4th January 2005, 15:01	#49 (permalink)
gurdeep_s Newbie Join Date: Aug 2004 Location: Bangalore Posts: 9	Octane rating of the fuel to be used in the vehicle is directly propotional to the Compression ratio. Some facts: 1. Fuel octane requirements for gasoline engines vary with the compression ratio of the engine 2. The higher an engine's compression ratio, the greater the amount of heat generated in the cylinder during the compression stroke. 3. The higher the octane rating on fuel the less volatile (evaporative qualities) and the slower the fuel burns. 4. Higher octane fuel contains more POTENTIAL energy but requires the higher heat generated by higher compression ratio engines to properly condition the fuel to RELEASE that higher potential energy. High octane fuel does reduce knocking due to the delayed ingition. But engines with low compression ratio are not able to utilize the potential of the high octane fuel and actually the performance may reduce using high octance fuel. Suggested Compression Ratios for Street Driven Engines (Source: http://www.ford-trucks.com/article/i...ion_Ratio.html) With cast iron heads, 9.0-9.3:1 is considered the maximum C/R for regular (87 octane) pump gasoline. 10.5:1 is about maximum for today’s premium (91-94 octane) pump gasoline with a cast iron head. And that’s assuming you keep the rpms up without lugging the engine, you’ve cleaned up the combustion chambers of sharp edges and rough spots to reduce the possibility of pre-ignition and use a zero deck clearance, or close to it, to enhance quench. Aluminum heads will generally allow 11.5:1 C/R on premium pump gasoline, again assuming you have clean combustion chambers and a zero deck clearance. If you run A/C, take .5 off the maximums. __________________ Gurdeep

5th January 2005, 12:08	#53 (permalink)
anoops BHPian Join Date: Mar 2004 Location: bangalore Posts: 151	you need to check the comp ratio of your engine, any thing above 9 will work well with 91 octane gas...generally the car manual will tell you what octane rating works the best. but the fuel we get here is not the best...so 87 octane might not actually be 87....thats the only danger. __________________ AAKGC- Activist Against Killing a Good Car

10th January 2005, 12:44	#54 (permalink)
iceman91 Senior - BHPian Join Date: Nov 2004 Location: melbourne/bangalore Posts: 1,330 View My Garage	well guys i used dom's mixture in my car and the response is almost immediate and the car burns better and is much more crisper...got an excellent mileage of 19.7 on the highway in my baleno...dom was sittin with me to prove it!!! __________________ ...91 is back !!!!

10th January 2005, 13:46	#56 (permalink)
iceman91 Senior - BHPian Join Date: Nov 2004 Location: melbourne/bangalore Posts: 1,330 View My Garage	dom did all for me...so u need to ask him and the mixture too is somethin he calculated according to the compression of my engine __________________ ...91 is back !!!!

4th January 2005, 08:44	#48 (permalink)
speedsatya BANNED Join Date: May 2004 Location: bangalore Posts: 1,882 View My Garage	Speed /Power is the regular 87octane petrol with additives. but IOC xtra Premium is 91 octane fuel.

4th January 2005, 21:39	#51 (permalink)
Domnic Senior - BHPian Join Date: Mar 2004 Location: bangalore Posts: 374	Yes, mpfi cars will benifit from the higher octane. You can use 91 on all the indian cars, no problem whatsoever... Cheers Dom

5th January 2005, 12:02	#52 (permalink)
speedsatya BANNED Join Date: May 2004 Location: bangalore Posts: 1,882 View My Garage	hey Dom ,i am talking abt changing the "octane type" in the ECM. can u list the cars in which this setting can be changed.

10th January 2005, 13:36	#55 (permalink)
speedsatya BANNED Join Date: May 2004 Location: bangalore Posts: 1,882 View My Garage	wat mixture ????????? are u talking abt the toluene. wat was te ratio uused and with wat fuel. how much did u get the toluene for????????? satya

10th January 2005, 16:57	#57 (permalink)
lamborghini Senior - BHPian Join Date: Apr 2004 Location: South Mumbai/Smithfield, RI, USA Posts: 2,652 View My Garage	hey dom will it be possible for you to send us some of it or like will we have to make it ourselves anyone here sell toulene or get it ??? was thinking of using it on my palio or ikon how much does it cost per litre ??? will there be anychange in performance of the carb if 91 octane is used . i mean FE and performance wise thanx __________________ ¢нєєяѕ ℓαмвσ lamborghinirules@gmail.com

10th January 2005, 20:28	#58 (permalink)
Domnic Senior - BHPian Join Date: Mar 2004 Location: bangalore Posts: 374	Hi, No probs, let me know how much qty you guys want, or else let me know the car type, amount of mods done.... ill get it when i come to bombay. Cheers Dom

10th January 2005, 20:53	#59 (permalink)
speedsatya BANNED Join Date: May 2004 Location: bangalore Posts: 1,882 View My Garage	hey lambo, u can get it through a chemist.or u can search for one at Dava Bazaar near CST

11th January 2005, 02:04	#60 (permalink)
lamborghini Senior - BHPian Join Date: Apr 2004 Location: South Mumbai/Smithfield, RI, USA Posts: 2,652 View My Garage	thanx for the offer dom satya happy bday will check it out after my exams __________________ ¢нєєяѕ ℓαмвσ lamborghinirules@gmail.com

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