First off, sepc of the engine:-

2.1 Pinto
10.7:1 CR
Piper OHC134 High torque cam
3 angled valves but std size/flowed head.
4-1 stainless manifold
45mm tapered throttle bodies
MS v3 ECU running MS Extra code

Now, I have a "conservative" spark map whilst I've been dialing in the fuel. I'm now happy with the fueling and I'm hitting the AFR target afr's I;ve set. Cruise econimcally at about 15:7:1 then ramps up to 12.6:1 at full throttle. No hesitation and starts and warms up excellently. So now it's time to move onto the spark map.

Now, I have no experience of tuning spark so the first thing I'm going to do is make some det cans but even if I do, I'm not sure I'd know how to use them. So, this is my current spark map:-



It aplha-n - i.e. TPS vs RPM.

Does anyone have any suggestions of any amendments to it BEFORE I get the det cans on it? I.e. are there any points where it's obviously way off? One thing I have noticed on the car is that the engine pulls really strongly at low rpms but then seems to tail off and seems rather flat at above 4500rpm, even though the afr's a bob on at that point.

All advice welcome and greatly appreciated - might even pop down to MSD at the weekend to see if they fancy taking the task on.