Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

What octane to run

dsnow
 Share

Recommended Posts

dsnow Member

dsnow

Posted
Posted

2002 C4S coupe manual (only mod on engine is PSE)

I know in the manual it says to run a minimum of 93 octane gasoline. Here in the western US most premium is only 91 octane. I have a place that is going to be putting in a pump site with 100 octane unleaded race fuel legal for the street. My question is should I blend the 91 with the 100 to make 93 or would I be just better off using the 100 octane straight. If your car is not built with the compression to take full advantage of the octane you are just throwing your money down the drain. Any help here would be great. I asked the dealer about 91 and he said it would be ok just a little loss in performance would not hurt the engine.

Also, alot of race fuel gets the higher octane by using MMT in their blends. In the manual it says not to use gasoline with MMT in it. MMT supposedly damages the catalytic converter. Any advice on this also.

Thanks for you help in advance

SOUTAHC4S

wross996TT Member

wross996TT

Posted
Posted

What brand is the 100 Octane...if it is VP...good to go. Yes you can mix it to get your 93 min. As the dealer said it won't actually hurt to run 91, just ECU will retard timing to prevent knock. Probably a waste to run straight 100 (although that is what I run all the time).

dsnow Member

dsnow

Posted
  • Author
Posted

This is regarding MMT in gasoline. The owners manual says not to run gas with MMT. Even though it says not to is it OK? I beleive it damages the catalytic converter? Does anyone know if VP has MMT in it?

Thanks

soutahc4s

dsnow Member

dsnow

Posted
  • Author
Posted

MMT is not a leaded based product. It is just a way that refiners use to get Octane. Queston is do you know if VP contains MMT?

Thanks

Once again it depends on the type. The 100 octane VP has no lead. See here:

VP

dsnow Member

dsnow

Posted
  • Author
Posted

Thanks for all of your help on this wross996TT. You have been very helpful.

soutahc4s

oh you mean this:

Methylcyclopentadienyl manganese tricarbonyl (MMT) It is sold under the tradenames HiTec 3000 and AK-33X.

here are the VP spec sheets:

VP spec sheets

VP PDF

I see no mention of MMT.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing
×
×
  • 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.