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*Pre-Order Round 2* Mustang S550 / S650 / GT350 / GT500

*Pre-Order Round 2* Mustang S550 / S650 / GT350 / GT500

$500.00 USD
$500.00 USD
Sale Sold out

This is strictly to save your spot for PRE-ORDER #2

Full amount will go to your order. This is FULLY REFUNDABLE at anytime. 

We had originally planned to deliver in February, but we decided to make several improvements listed below. This is easily the most intricate production header system ever offered.

Pre-order #1 - Completed - Fulfilled April/May 2026

Pre-order #2 fulfillment target is August/Sept 

1) The flat 4-1 collector, while cool and different it is not optimal for sound. The quick split into two separate pipes doesn't allow a thorough mixing of both banks. 

2) The extra long midpipe had too much volume which resulted in low exhaust velocity and dulled some of the sound. We tested it with a single larger diameter pipe and there was a noticeable improvement.

3) The O2 sensors were previously only taking readings from one secondary (two banks). The updated design gets O2 readings from all 4 cylinders per bank now. 

4) A catted version will now be available using four cats. 

5) We made the headers modular. The headers can be converted to equal length tri-ys for a different sound ( this will be later in the year )

6) GT500 kit will be  plug and play. No more oil pan trimming


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DESIGNED WITH SOUND IN MIND

Concept841 uses equal lengths and a single collector to create a uniform exhaust pulse that produces the distinct sound of an even-firing engine. The collector recieves an exhaust pulse every 90 degrees creating continuous scavenging, further amplified by a smaller collector volume.

Simply Put: Its Al About Balance.