Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Performance and Technical Chat

Post Reply
LinkBack Thread Tools Display Modes
Old 04-28-2023, 01:31 PM   #1
01 Seal Gray 986 S
bg305's Avatar
Join Date: Sep 2019
Posts: 161
E85 stock / no flex sensor / tune.. ??

I am not advocating anyone do this, nor have I ever tried it myself.. I am just curious to see what others who know more on the subject then I do think..

This video:

Claims if I am understanding correctly that they run E85 in a 987.1 Cayman (without cats but claim it would not matter) with no issues relating to running lean.

Everything else I have encountered regarding E85 in general says usually stock tunes will not alter the air fuel mixture to compensate for ethanol's lower power density which ideally should be something like 9.8 to 1 where E10 / regular gasoline is 14.7 / 1. To make it more complicated E85 can actually vary quite widely on Ethanol content anywhere from ~50% to ~%85 which will alter the optimum A/F ratio which is why flex fuel vehicles have a sensor to alter the A/F ration on the fly.

So, can this guy be accurate? is there something here I am missing? Do Porsche ECUs compensate? He mentions that the car ran rich to begin with.. but ~10 or 11 to 1? seems unlikely. I will admit my 986 (with Fabspeed 200 cell cats) has its own unique rich smell to it.. But just pumping E85 in and all is well???

bg305 is offline   Reply With Quote
Old 04-28-2023, 01:37 PM   #2
01 Seal Gray 986 S
bg305's Avatar
Join Date: Sep 2019
Posts: 161
Listening again, I did notice he mentioned having spacers on the O2 sensors with the open exhaust (not sure why that is needed? perhaps to compensate of the lack of cats cleaning the exhaust?) and that causes it to run rich? (hence why it running well on E85)

bg305 is offline   Reply With Quote
Post Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -8. The time now is 10:14 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2023, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2023 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page