Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 13 - Jul 18
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Borla 400371 - XR-1 Multicore MufflerDesigned for rotary engine equipped vehicles, but can be used on other applications. Compact size is perfect for applications with limited space. Reversible design for installation flexibility. Patented Multicore design for maximum power. Recommend for high horsepower applications. T 304 Stainless steel will never rust. 100% welded construction for strength. High temperature continuous filament fiber (CRF) accoustic material for sounds control. There
Designed for rotary engine equipped vehicles, but can be used on other applications. Compact size is perfect for applications with limited space. Reversible design for installation flexibility. Patented Multicore design for maximum power. Recommend for high horsepower applications. T-304 Stainless steel will never rust. 100% welded construction for strength. High-temperature continuous-filament fiber (CRF) accoustic material for sounds control. There is no logo embossment on this part. Best of all, it's made in the USA. Just what you?d expect from the world?s most experienced (and most winning) exhaust brand.
Specifications:
| Description_ASM | XR-1? Multi-Core Racing Muffler For Rotary Engine Equipped Vehicles - 3" Center Inlet/ 3" Center Outlet 4.25" x 7.88" Oval x 16" Long Body 21" Overall Length. Universal Part. Reversible Design. |
| Description_DEF | Exhaust Muffler |
| Description_DES | XR-1 Multicore Muffler |
| Description_EXT | XR-1? Multi-Core Racing Muffler For Rotary Engine Equipped Vehicles - 3" Center Inlet/ 3" Center Outlet 4.25" x 7.88" Oval x 16" Long Body 21" Overall Length. Universal Part. Reversible Design. |
| Description_INV | BorlaXR-1 Multi-Core Muffler |
| Description_MKT | Designed for rotary engine equipped vehicles, but can be used on other applications. Compact size is perfect for applications with limited space. Reversible design for installation flexibility. Patented Multicore design for maximum power. Recommend for high horsepower applications. T-304 Stainless steel will never rust. 100% welded construction for strength. High-temperature continuous-filament fiber (CRF) accoustic material for sounds control. There is no logo embossment on this part. Best of all, it's made in the USA. Just what you?d expect from the world?s most experienced (and most winning) exhaust brand. |
| Description_SHO | XR-1 Multi-Core |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.2 ★★★★★
Based on 1345 reviews
Sort
Product Reviews
★★★★★ 5
Great fit
Color: Crisp White, Size: Small
Shirt is great. Nice fabric.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 22, 2026
★★★★★ 5
Good quality
Color: Crisp White, Size: Medium
Fit is great, feels like a durable material. Generally a very nice shirt! Bought this for a 5’ 10” male who is 150lbs. Medium was just right, with a little bit of breathing room.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 14, 2026
★★★★★ 3
Good for an emergency only
Color: Crisp White, Size: X-Large
Shirts are good overall, but the material is too light ... if you are hairy or have dark skin, you need an undershirt; otherwise, it looks like the shirt is dirty.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 14, 2026
★★★★★ 5
Great shirt for Price
Color: White, Size: Large
Seem to fit true to size and long enough. I cannot stand dress shirts that are too short on the sides and become untucked. I am also getting these embroidered with a company logo to turn into work shirts. I like the oxford feel, buttons are tight fit, arm length is hair long for me (5'11") - but for the fit they fine. I purchased four of these, all were consistent with one another, no surprises.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 1, 2026
★★★★★ 5
Might buy a couple more.
Color: Demin Blue, Size: Large
In the process of losing weight and needed a nice looking shirt for work without spending a lot of money on something that will only fit for a few months. This did the trick! Fits well, looks nice, and at a great price.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026