Hi everyone,

I figure this might be useful for someone out who's curious. I've been doing a series of ignition upgrades in the interest of achieving better performance out of the 1275 metro turbo motor. So far I've installed a Mallory Hyfire 6EZL unit, and this past weekend I have also installed a MSD BTM (boost timing master). Nothing has caught on fire just yet. It is a bit of a rats nest:

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The Mallory unit is basically fires each spark plug multiple times and amplifies the overall spark voltage allowing me to run larger plug gaps without breaking up (running at .042" gap right now). I installed the BTM in order to better manage off boost and boost transition timing. The BTM lets me retard the timing x degrees per pound of boost (I run about 8psi). Currently running 20 degrees at idle, 32 degrees total timing when not boosting and 28 degrees (as standard) at full boost. The timing map, as you would imagine, is a bit complicated.

Without access to a dyno (and a lot of tuning time) it is difficult to see the real world gains, but in theory (yes, could easily get me in trouble), the car off boost and up to transition should produce more power due to the advanced timing (improved around town driveability), and should create the same power when boosting. I also have the added benefit of having an in-cabin boost timing retard **** which adjusts the degrees/psi ratio on the fly (if I run race gas tomorrow, I can run less retard for more power, or if I only have access to 87 octane, I can run more retard to prevent detonation).

The tuning process can be considered complicated, involving an adjustable timing light, spare boost gauge, bicycle pump and an assistant. Everything is based on the magical number of 28 degrees BTDC at full boost (known to be safe). The very abridged version of the process (I did a lot more back and forth, fact finding, check and rechecking):
1) Attach bicycle pump to BTM unit (it has a boost sensing port)
2) Tee in the spare boost gauge between pump and BTM
3) Detach vacuum advance from distributor
4) Rev engine up to 4000 RPM to engage full distributor advance (28 degrees)
5) Assistant pumps and holds 8psi
6) Set boost retard **** to retard 1degree/psi. At 4000 RPM and 8psi, the timing light should now read 20 degrees
7) At 4000 RPM and 8psi, Advance timing to 28 degrees by turning the distributor.
8) Take a break
9) Go back to check the work. Run the motor to 4000RPM, Pump 8psi, make sure the timing shows 28 degrees.
10) Shakedown, listen for detonation, do a plug chop.

The car feels peppier, the plug chop looked clean.

Today while driving, I decided to turn up the fun **** just a LITTLE bit without a timing light on hand. The car was a little bit more responsive, no audible detonation, however, checking the plugs revealed a small amount of detonation. The boost retard **** will now be returned back to the original setting.

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I can see more gains by advancing the base timing even more, then changing the boost retard to take 1.5 degrees out per psi, but will likely need a dyno to verify this. Thoughts, questions, concerns always welcome