Because everybody seems to have an opinion about this throttle body that I've offered for sale....
I thought that I would post this, from the SVT Performance website's discussion on the AccuFab twin 60mm throttle body being used on the Mach 1 Mustang.
(the same throttle body and the same engine as a Marauder)
George Klass's (from AccuFab) comments:
Let's talk about the 99-01 Cobra TB (also fit's the Mach 1). As many of you probably know, most of our TB's are single blade units. Unfortunately, a single blade unit won't work on the 99-01 Cobra because (as was pointed out above) the IAC port is in the way, and the center "bridge" would have needed to be removed, the car would have idled at about 4000 RPM, not a good idea. Removing the bridge on the 96-98 Cobra intake is not a problem as the IAC port is not disrupted.
Anyway, we learned alot while developing this dual-blade unit (took almost a year and 8 different versions, all tested on our flow bench).
We found out that "the size of the hole", usually measured in MM) is not as important as the area IN FRONT of the blades.
As someone above mentioned, it's not the size of the blades on the OEM TB that is the problem.
The problem in airflow is the air seperation that takes place on the OEM unit, in front of the blades.
This is what restricts the CFM, not the size of the blades.
I'm not going to bore you with these details, especially not on a Monday, so you will just need to trust me a little in this area.
I can just say that we flow test EVERBODY's throttle bodies, not just ours. We also dyno test them all, on Westech's engine or chassis dyno.
If we can't show more HP than stock, we won't offer it (which is why we do not sell TB's for the 94-95 Mustangs).
The new TB for the 99-01 Cobra has just been dyno tested, back to back with the OEM unit, and is worth about 9-10 more HP on a dead stock engine.
Slightly more if you have increased initial airflow with a cold air kit, better filter, etc.
This test will be in an upcoming MM&FF magazine since it was done by Richard Holdner.
As most of you know, Accufab is down the street from Westech and we are on the dyno 3 to 4 days a week testing some damn thing or other.
If you have questions you can email me anytime at accufab1@aol.com or call me at Accufab, (909) 930-1751. Cheers.
There is alot more to building a throttle body than just making the blades (and hole) larger.
Airflow is everything. Bigger holes are nothing.
We were just lucky before with our Mustang 5.0 TB's. With those units, bigger holes meant increased airflow. We go up to 105MM TB's for the 5.0.
The 105MM TB flows 1550 CFM.
Just to keep everything relative, the 03-04 Accufab TB's (same for the Lightnings and the "big" units for the 96-98) flow 1696 CFM.
The 99-01 Accufab TB's will flow about 1284 CFM. OEM is about 1089 CFM.
Like I said, the dual blade units for the 99-01 will not make a big increase but you will feel it in the seat of the pants.