MPS adjustments for a 2056cc w/Raby cam Options

[Bleyseng]

I finally have gotten the MPS for 2056 with the Raby 9550 cam adjusted right. Blair and I got a LM1 meter and tuned it using my laptop and driving around for load testing, then jumping out to minutely adjust the MPS to set the A/F. Took awhile but it is amazing to drive the car and change the A/F setting a tiny hair of a turn to go from 12.5 to 13.5 to 1. Wow, the MPS diapharam setting are that delicate but I was able to set the cruise, idle and WOT and the car runs super sweet now. Tons of power all thru the rpm range until 6200 where I stop. I haven't noticed the high rpm lean out others have reported as the WOT and cruise A/F stay stable until 6200 rpms right where I set them up.

Basically, a short cut would be to use a 037 MPS thats factory calibrated as that is very close to where I ended up, maybe a hair lean.

Using a Wavetek my baseline reading are for my tuned MPS:
15hg- .78
4hg-1.32
0hg- 1.58

Compared to my readings of a 037 OEM MPS:
.15hg-.75
4hg-1.27
0hg-1.53

I set my A/F ratios to 12.5 to 1 at WOT, 13.6 to 1 at cruise and idle.

Using the 9550 cam, HD valve springs, and the bigger exhaust valves (38mm) demand more fuel over a stock MPS. I have installed a NOS 043 MPS and it runs ok but the A/F reading are closer to 14 to 1 and hesitates instead of taking off smoothly. Dropping down to 13.6 to 1 on cruise really smooths the engine out and you have to set the WOT at 12.5 to 1 to get the power and smooth run up the rpms scale.

Blair and I will be playing with this more just to see what all more we can figure out or damage... I can see where the programmable EFI would really be fun. This is old school but it again proved that the Djet is fairly tuneable and adjustable to modified engines.

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