[Supras] MSD spark retarder and piggybacks

[berniek at technicaldevelop.com]

Wade:

    The MSD retarder works by retarding timing only by one present 
amount (adjustable to 8 or 10 degrees maximum retard) once 12V is 
applied to it via a manifold pressure switch or other 12V switching 
device.  It is adjustable in 0.1 degree increments but only offers a 
fixed level of retard, in on-off fashion. 

    I'll be using 550cc injectors, Lexus AFM, Walbro pump and a 57 trim 
CT26, and have the objective of 15 PSI boost.   As stated  in  the post 
just submitted to Rocky and you, NJ emission limits are stringent, but I 
do have an 80mm HKS cat-back system.  If and when NJ removes chassis 
dynos, a freer exhaust will be a first move. 

    Looking for continuously changing retard and fuel takeout devices 
with front panel controls proved fruitless.  Apparently the only way to 
really do the job with purchased devices is to have the time to build 
your own fuel and spark advance maps with a laptop in the car.  I wish I 
had the time to install the various pieces, do the tuning, but do not.  
So, I'll let the knock sensors modify the spark retard ECU mapping under 
boost (must be built-in, to cover differences in fuels world-wide).  At 
first I'll live with the excessive top end richness.  I have a pump 
suitable for water injection, but will not have the time to install it 
first.  If anyone remembers the McMaster spray nozzle number for this, 
I'd appreciate knowing it. 

    Now for the crazy but seemingly logical part, based on simplicity:  
Later, I can use a simple ball and spring boost controller to bleed high 
boost from the vacuum line to atmosphere at the FPR to taper off the 
boost seen by the diaphragm of the FPR.  That will cut back fuel at WOT 
and high boost by lowering the diaphragm pressure slightly.  There will 
be enough friction loss in the hoses to and from VSV2 to act as a 
restriction for the "relief valve" to work.  I'm relocating both VSV2 
and the EGR VSV to above the intake manifold (freshened engine is now in 
car with 57 trim turbo, but with only the lower intake manifold.  Still 
need to install quite a few parts, so relocation is easy).  Tuning with 
higher than stock boost will be done with a wideband, stock O2 sensor 
with extended endpoint LED readout, or an EGT setup. 

    I'd be very curious if anyone has removed excessive boost fuel by 
slightly lowering fuel pressure as just described.  If nutzoid, there is 
a good sanitarium less than 10 miles away. 

       Bernie