SureTrack Users General Discussion

[Glide]

What is the vehicle? What was the customer complaint?
I agree about modifying diesels,it never turns out well and egr delete also deletes valuable data for diagnosis.

[greasybob]

08 F250 6.4. The vehicle was already somewhat disabled when I got but I did manage to do a relative cranking compression test. I put a new piston and rod in it, honed the cylinder and had the heads checked. It had already been studded, all seems good for now. Sorry my image resizing software not working.

[diesel71]

nice work bob, did you do an after repair relative com. test ?

[greasybob]

I finally got the vehicle back here to check over my work and took some relative cranking samples to compare. Note that the engine was warm and batteries fully charged so the scales may be different than before. Things look pretty good. Once and while I can find a slightly low cylinder that repeats every 8 spikes. No codes. It's sad that there isn't much for injector balance data on these. Still haven't found a new image resizing software.

[greasybob]

Question of the day. Does high octane fuel actually have more energy or does it just enable better conversion of energy by allowing higher compression and different timing management ? I suppose it would also depend on how you are obtaining the higher octane rating such as which additive you use. Also would using a lower octane fuel in an engine that recommends a higher octane fuel effect the fuel trims if no knock or misfire was detected and the ECM made no timing adjustments. To effect fuel trims the combustion process would have to consume more or less oxygen which could be an indicator of power produced ?

[Matt]

I was told that higher octane does not mean higher energy content (btu's). It just represents the fuels ability to resist preignition. The way I see it, if your engine doesn't require high octane fuel due to high compression, its not going to benefit you. Also, higher octane fuel tends to vapor-lock worse in old carbs too.