By Borla

Borla Boomer Muffler Thumper Oval 2-1/4in In 4in Side Rount Out

Regular price $513.95
Regular price Sale price $513.95
Shipping calculated at checkout.
Availability: In stock
SKU: BOR40057
Regular price $513.95
Regular price Sale price $513.95
Borla(r) Boomers are full-blown, high-tech, dyno and race-proven mufflers for the street or track. These eye-popping, fully polished, T-304 stainless steel mufflers feature integrated polished tips, and utilize Borla(r)'s patented race-winning technology for improved exhaust flow. In addition to adding head-turning sound, they also add a modest boost in horsepower. They utilize 100% welded construction for strength. High-temperature continuous-filament fiber (CFF) acoustic material for sound control. Natural mill finish can be brushed or polished prior to installation. Available in a variety of universal-fit styles, Borla(r) Boomers are made in the USA from aircraft-grade high-quality T-304 austenitic stainless steel and include a Million-Mile Warranty.

What clients say


  • Really fast and high quality customer support, my order got to me faster than the quoted time too. No complaints

  • The team took a mostly broken car after some work done elsewhere, and have systematically made it reliable and fast for a fair price. The staff are invested in the work they do which also makes a big difference.

  • Jeff was extremely helpful in assisting me with my exhaust. Always kept me updated and answered any queries in a timely manner. Will definitely be coming back for my future mods

  • Justin and his crew is amazing! Always ready to help and service with a smile. Trusty, friendly and reliable! Had my car sent in for repair twice and it’s fixed on time, at a reasonable price and with no issues. Highly recommended!

  • Easy to deal with and part was ordered quickly

Fitment & Compatibility


How do I know if this part fits my car?

We recommend checking your vehicle's make, model, year, and variant carefully. Most product listings include compatibility notes, but if you're unsure, contact us before purchasing.

Can you confirm fitment before I place my order?

Absolutely. Send us your VIN or Rego and we’ll confirm fitment for you.

Do you offer installation at your workshop?

Yes, we offer installations for most parts at our Ringwood workshop. Contact us to book or get a fitting quote.

Shipping & Handling


How long will it take for my order to arrive?

Most in-stock items ship within 1-2 business days. Delivery time depends on your location and shipping option chosen at checkout.

Do you ship internationally?

Currently, we only ship within Australia. For international enquiries, please contact us directly.

Can I pick up my order in person?

Yes, local pickup is available from our Ringwood workshop. Simply select ‘Local Pickup’ at checkout and we’ll notify you when your order is ready.

Please note: Some items are stored offsite and may need to be transferred from our warehouse, which can add a few business days before pickup is available.

Returns & Warranty


Can I return a product if it doesn’t fit?

Returns are accepted within 14 days if the item is unused and in original packaging. Please see our full Returns Policy for details.


What warranty comes with your products?

All products come with the manufacturer’s warranty. If you experience any issues, contact us and we’ll assist with the claim process.