Jump to content
The mkiv Supra Owners Club

Supra minimum octane requirements


Samurai 20V

Recommended Posts

Hi Guys...

 

I am a potential Supra owner, I will be going to Japan for work & am looking to buy a TT Supra to import back to South Africa.

 

My main concern is the min octane rating that the 2JZGTE can accept. In SA we only have 95 unleaded on the pumps. Race fuel is 98 octane but very expensive & not freely available..

 

I was looking at getting a Supra with BPU at the minimum, so running around 1.2bar boost. Will it be safe to run such a Supra on 95 fuel? I understand that the Stock ECU can detect detonation via the knock sensors & compensate by dropping timing....

 

I saw one Supra for sale on the web with a Mines CPU, will this operate similar to the stock wrt detonation?

 

Following on from that is it safe to use octace boosters such as NF & NOS?

 

Sorry for many questions, i'm a bit inexperienced wrt boosted cars.

 

Thanks...

Link to comment
Share on other sites

With the MINES ecu running a more aggressive fuel and ignition map I would have thought it would be even less likely to run on 95 without det but in either case I wouldn't want to run a JDM Supra at 1.2bar on 95 octane even on stock ecu.

 

All that hot air from those turbos running past their efficiency range plus the ambient air temp is SA probably being very warm already sounds like a recipe for det on stock ecu & BPU.

 

I suspect if you use 95 you'll be restricted to stock boost levels unless you have the car mapped specially for a lower grade of fuel though I'm still learning so someone more experienced I'm sure can confirm for you.

Link to comment
Share on other sites

Is the 95 octane the same as our 95 octane or is it more like the US 93 octane?

 

I don't know enough about about the fuels to comment but I understand that the quoted octane figure is not the most important when it comes to det.

Link to comment
Share on other sites

Do you know if the 95 octane unleaded in South Africa is in RON, MON etc?

 

I think UK 98 Octane is in RON which is ~90 MON therefore 95 MON I would have thought would be over 100 RON Octane in UK?

 

See if you can find out what system is used to measure the octane number in South Africa!

Link to comment
Share on other sites

@Caseys - Importing cars into SA is basically not allowed, its only in cases such as mine were a returning resident can bring in a car, so I pretty much have to bring the JDM spec.

 

@ Scott M & leebuk - the 95 unleaded is 95 RON...:(

 

So is it safe using the octane boosters like NF & NOS continously on a 2JZGTE?

 

We have a locally produced octane booster called DF20, which has caused lots of damage on my mates 4AGE 20V engine, so I'm a bit sceptical...

Link to comment
Share on other sites

Thanks for all the responses guys...

 

I think maybe I will consider running on stock boost for normal use with 95 pump fuel & throw in an octane booster or race fuel (98 RON) on track days & crank the boost up!

 

I think that an Air/fuel Ratio gauge might be a good idea to keep an eye on the mixture to ensure its not running lean...

 

Japan are so fortunate to have 100RON at the pumps!!:(

Link to comment
Share on other sites

Be careful with the octane boosters. I remember reading that a lot of them are fake and do absolutely nothing to the true RON of the fuel.

 

There are some that do do the trick though :)

 

 

So which are the ones to use & the ones to stay away from?

 

Down here NF seems to get good reviews. There are some local ones that I will definitely stay away from.

 

Should I just use toluene? Its fairly cheap down here & easy to purchase, no requirement as to what its being used for. Will it affect the engine in any way?

Link to comment
Share on other sites

I had my supra in Ireland which has the same fuel issues ran 1.1bar for 6 months and the engine blew! New engine in and 0.9bar was all i could run on 95 even with octane boosters i was using millers oils cvl turbo octane booster which is pretty expensive 1 bottle only treats 20litres of fuel. I think it will be costly to try run bpu with 95. In the end i had to move back to the uk to save the car. If its only a jdm supra you can get in keep it stock mate.

Link to comment
Share on other sites

  • 10 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.