Photo’s of Our Work:

Not only can we port and modify your current TB&PL,
we also carry the full line of Dragon® throttle bodies and plenums.

Throttle body and plenum modifications should not be taken lightly. Air flow restriction in this area will limit HP potential. Stiegemeier offers port-matching to fully welded and enlarged plenums to deliver all the CFM your throttle body has to offer.

**Please Note: OEM throttle bodies have the best driveability! After-market single-blade types will almost always improve HP and TQ but usually demand attention from an experienced tuner.



03′ & 04′ Cobra porting bench flow data

* All bench flow data was measured on a Super Flow SF 600.
Bench flow data was measured @ 10″ of pressure, final numbers were converted to 28″ data via pressure conversion constant of 1.67.
Example of converting 10″ data into 28″ data: (593.5 cfm x 1.67) = 991 cfm

CFM Flow,                        Demonstrated Power Gain               Description of Work

878,                                                        Stock,                                                           All Stock

                                           976,                                                       +10HP,                                 Stock Throttle Body with Welded and Ported Plenum

                                                                     991,                                                        +12HP,                                   Ported and Welded Throttle Body & Plenum