Black Friday - Holiday Sale Now Through December 25th, 2022!

Receive 5% off on all Kits! - Applied at Checkout

Order your Kit Today!

Order Today! - *Due to demand & material supply, Lead-times may vary.*

Proudly Designed and Produced in the U.S.A.! Business Hours are: M-Th 8:00-4:00pm CST & F 8:00-Noon CST

Introducing PORTER MUFFLER'S to our Family of Brands!

Shop Porter Mufflers to own that Steel-Pac Sound that has been Made in the U.S.A. Since 1931!

Shop Porter Muffler's!

We are here for any Questions and Technical Support on your Project!

Please give us a call at: (763) 767-4480 -or- (608) 299-7427 or via email to: sales@transmissionadatpers.com

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WILCAP Transmission Adapters

Speed Gems is The New Home of WILCAP - Early Hemi Adapters!

Shop Wilcap - Please Call for Order Details and Lead-times!

Reverse Engineering Capabilities and Design Available for your Project! - 3D Scanning and Printing for Custom Parts!

Please give us a Call to discuss your Project! - *All Products are Intellectual Property of Speed Gems*

In-house Machining Capabilities Available

Visit www.savannahprecisionmachining.com for Custom Machining Quotes!

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