Amazon: What fuel ? do you use ?

[volvogv]

This all sounds like good advice. That's what makes this forum so great...the collective expertise of the members and no matter what the problem, somebody has already worked it out.

I've been using ethanol for years in other cars so I know what it can and cannot do. As an experiment I added a small amount to the regular fuel and confirmed the SU's are too lean to run alcohol. Alcohol requires a richer mixture. I pulled the choke (which really isn't a choke but a fuel enrichment device). With the richer mixture and high octane, the car really came to life! Since I'm headed back to college in a few days I don't have time for experiments so I've going back to 100% petrol. I have a couple of observations from this experiment:

- If the fuel system could be "hardened", it's possible to run ethanol fuel successfully if the engine is retuned properly. But as one poster mentioned, it can't go back and forth between fuels without retuning. Modern cars trim the fuel mixture automatically.

- Our state mandated 10% ethanol/petrol blend is causing my engine to run lean, which confirms what you guys have suggested. Get this...when I drive home at night, the air temp drops from 70F to 40F and I have an elevation gain of 2,500 feet. No wonder it runs so poorly after dark!

This weekend I'm going to follow your advice and retune the engine.

[tdz840]

Have you considered going to a different profile needle, or experimenting with yours?
You could have needles for 'normal' fuel and needles for ethanol enriched.
That is if the two conditions are so different they cannot be contained using normal tuning methods.
If you google Burlen Fuel Systems they can provide different profile needles for about £15 delivered (ea)
Russ

[Volvo Canadian]

A late-comer. I was going to say that the fuel you are running will affect your timing, so which ever one you choose, stick with it, having tuned your ignition system accordingly. I ran mine on premium, but have since decided it is not worth the extra cost and followed the above....

YES you can mix leaded and unleaded. I was told many years ago 3 parts unleaded to 1 part leaded will provide enough cushion for the valves, in case you want to go that way.

[volvogv]

I never intended to hijack this thead so i apologize for that. I will say that I made carb adjustments this morning and now the cars runs really nice.

[ranjit200]

Originally Posted by Volvo Canadian

A late-comer. I was going to say that the fuel you are running will affect your timing, so which ever one you choose, stick with it, having tuned your ignition system accordingly. I ran mine on premium, but have since decided it is not worth the extra cost and followed the above....

YES you can mix leaded and unleaded. I was told many years ago 3 parts unleaded to 1 part leaded will provide enough cushion for the valves, in case you want to go that way.

After changing fuel to V-power nitro+ I felt uncomforted in driving and had to re-tune the carb over and over and didn't wanted adjust timing , felt uneasy so now I am back on sainsburys super unleaded and feels good to drive without having to deal with timing and re tuning.
What I mean to say that it is what you have mentioned that :

Originally Posted by Volvo Canadian

the fuel you are running will affect your timing, so which ever one you choose, stick with it, having tuned your ignition system accordingly.

Thanks
regards...ranjit