M-9989-A1 converts V6 TPS plug to 5.0 TB's!!!
1. Re-drill bolt pattern for V6 TB pattern
2. hack off MOST of the throttle arm (leaving the
return spring portion)
3. grind the remaining surface FLAT
4. weld on MOST of the 3.8 throttle arm (less the
return spring portion, just reuse the part the cable
hooks to)
5. making the crossover tube larger is a MUST and a
big job! 55mm at least... that matches the
flow rating of the 60mm TB (remember, no shaft to
block airflow)
6. Re-use your 3.8 IAC (idle bypass motor)
7. SPLICE in the 5.0 TPS to your 3.8 wiring harness.
The 3.8 TPS is "clocked" 90* off from the 5.0 TPS...
Other than that, it is a "simple bolt-on!"
60mm is also the practical limit for the 3.8 Upper,
the "choke point" can only flow about 550 CFM and the
5.0 TB is rated by FORD to flow 535-540 CFM. it is
very hard to port the choke point on a 3.8 Upper,
because it would intrude into the bolt bosses of the
upper to lower intake hold down bolts.
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5.0 TPS to 3.8 wiring harness wiring schematic:
5.0 TPS colors.................goes
to..................3.8 harness
Green/Green..............................................Gray/White
Black/White..............................................Gray/Red
Orange/White.............................................Brown/White
base color/tracer (stripe) color
**** Note! Not all 5.0 TB's have the tracer color, but
it is listed
for those that do.****
When cutting the 3.8 harness wires, leave enough wire
on the plug to reinstall it in the future
if the car is ever returned to stock condition. Use
butt splices and shrink wrap to connect wires.
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Gaston:
2 minor additions to RGR's info:
-There is a TPS part number for later
(towards '93) for 5spds and others for aode,
I ordered one of each and one is clocked 90*
and the other is not. I forget which is
which, they both work and cost the same so
this is useful info
-FMS sells a SN95 to "fox" TPS adapter. Its
not too expensive either, only like $10, if
you want to avoid the splicing.
This is something RGR posted on v6p a while back, it may help.
