Edelbrock 3.25in. part #15873 pulley allow you to fine tune the airflow and performance of your Edelbrock Supercharger System to your preference. Edelbrock pulley is a 8-rib design for use with any of our Professional Tuner systems. Edelbrock pulley feature a black anodized finish. 3.25in. 8-Rib Edelbrock's/C Pulley in Black Finish for - Pro Tuner System.
15873 is a 3.25” pulley.
The old TVS2300 (1558 - 1559) came with 3.50” supercharger pulley standard.
The new TVS2650 (15595) comes with 4.00” supercharger pulley standard.
Generally, for every .250” change in pulley size (down or up) would net 1.5 to 2.0 psi of boost and can vary depending on other items such as elevation, heads, cams, long tube headers, cat deletes, cold air intakes and so on. As with any pulley change it would require custom tuning and possible shorter belt. You should hook up a boost gauge to validate what the vehicle is making and consult with your tuner.
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