You dont tune at Stoich.
You want 12.1 max really , and mid 11s min
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I didn’t for one moment say that was the case. Perhaps if you had come on here and not immediately started lecturing you might get more help.
I never lectured. I pointed out that unfortunately the AFR and power lines had been confused by someone else and that tuning at stoich isnt the way to do things.
I am unsure quite on how else I could have said things?
My apologies as offence was never intended.
The graph you posted with AFR also has a power curve, which is the same as the power curve on the other two graphs. The latter is the one that rises and the AFR is the flattish one that runs between about 12.5 and 13.7.
That was as Trackrod pointed out.
Improvements in lean burn, materials and the ability to model combustion accurately now allow running much closer to stoichiometric than was the accepted norm. Much of that work has been driven by the need to lower emissions from hydrocarbon fuel.
I assume you have already checked the more obvious causes of low power? Looking back briefly, the rough increase for the base Katana kit seems around 20-25% so around 225-235 (based on 190 normally aspirated) rather than 255…
Factor in, too, dyno variability, air temperature, density, etc. and frankly I don’t see yours is doing anything massively wrong.
Sorry if I caused some confusion. Typically the values above 14.7 are considered as lean and below as rich running.
As you were talking of ‘Scary Mary lean’ and ‘way too lean’ and I could only find values between 12.5 and 14 I thought you might have taken the power curve for the AFR curve.
As this was not the case everything is fine.
I am with you on the lean burn etc, however I also have the injector duty cycle that is high and they are wide open.
I based the 255 on figures that were quoted by the orginal owner.
My seat of the pants dyno was withing 6bhp of the dyno dymanics run.
Ill carry on the quest for more reliable , safe power increases.
All good, friend 
2zz seems to produce best power in the mid 12,s …
Going much richer drops power off a cliff.
Lotus engineers have aimed for 13.5 ish , presumably to help with emissions.
I did a huge,amount of testing about 5 years ago .
In the end I ran 550 injectors with a 2.8 pulley around 330 bhp but it proved too loud for UK tracks and I sold the car
Mid 12s are good, I can cope with that. Mine was just 13 upwards when the power really came in.
Did you run OEM Ecu @jfk?
Totally stock Lotus 260 ecu …
It does learn and trims settings to maintain safe running despite what some say …
As long as things like injectors can flow the necessary amounts of fuel
Interesting.
Mine is a T4 ECU , I assume yours was a E variant as you would have had FBW throttle.
So is it really a case of just geting myself some bigger Lotus injectors ( suggestions please? I was going to use either Siemens Deka 66IB or some Astra VXR ones for the aftermarket ECU ) fit my chargecooler, smaller pulley ( I have a 74mm one ) and a cheeky 260 flash map by lotus?
I used these
Cool, thanks for the info.
Ill try and find out if my T4 can accept a 260 map.
I should have all the parts to make the car a “lotus” setup other than the snout on the supercharger with me by early next week
I will then have the chargecooler fitted, a suitable ECU ( SCS is favourite at the mo ) injectors ( probably astra VXR ones, or Seimens Deka 66ib 630s ), smaller pulley , new fuel pump and take some advice on the oil cooling situation.
Random failure this evening. The nearside wing mirror has ceased to be in its designed location.
Ordered and new one , and some rattle can paint …
Last part from the US arrived today. NLA in UK so had to import one from there at twice the cost of the part in the UK …
Another puzzle - I have a FED ecu …
I wonder whats going on here?
Either way , waiting for the ECU loom and then its off to get fitted / mapped
Sorry Andy… only just saw this thread… I had a Katana as well… pretty much same issue… loads less power than it supposed to have and not a good map - I tried to get Sinclairs/Essex Autosport to sort it out with no luck - I also learnt that non intercooled was a ticking bomb… in the end I went for a Hangar 111 280s kit and went charge cooled and a proper map and now have a car that makes the power it is supposed to…
Hi buddy, thanks for the input.
Today I dropped my car off at RSTuning to have the chargecooler fitted and all the parts.
I have also got a new ECU and loom being fitted , as well as aircon condenser.
Hopefully get some progress towards the back end of the week. No rush from my side …
cool - interested to see how it goes… I think the manual throttle cars like ours are a bit more challenging to get right - what ECU did you go for ?
Jon