Borla Exhaust FAQ: Scion tC Axle-Backs, Multicore Race Mufflers, and Real Shop Questions

If you landed here because a search engine sent you mid-project, let me save you the scrolling.

I work in product support at Borla. When a dealer calls needing a Borla Scion tC axle-back S-Type exhaust system before a weekend event, or a shop is underneath a 1.9 TDI with a downpipe half out and the wrong socket set beside the jack, I'm one of the people who answers.

The questions below come up again and again. Some are product questions. Some are basic what-do-I-do-now questions. Both are fair when the clock is running.

What's the difference between Borla Touring, S-Type, and ATAK exhausts?

Quick version from calm to loud:

• Touring is the refined one. It deepens the note without turning the highway into a conversation problem.
• S-Type sits in the middle. More aggressive than Touring, but still daily-driver friendly.
• ATAK is the most aggressive sound in the Borla street lineup.

But the difference isn't only volume. Each muffler uses a different internal layout, so the character changes too. ATAK has a raw bite at full throttle. S-Type sounds purposeful without shouting. Touring stays composed when you're cruising.

In my opinion, S-Type is the pick for someone who wants to hear the exhaust when they step on it and still be able to hold a conversation the rest of the time. ATAK is for owners who treat volume as a feature, not a side effect.

Which Borla Scion tC axle-back S-Type exhaust system should I buy?

When someone orders a Borla Scion tC axle-back S-Type exhaust system, the first thing I check is the model year. The tC had two generations with different rear sections, so don't trust a forum photo. Fitment is vehicle-specific.

The axle-back is designed to bolt to the factory mid-pipe and use the original hanger locations. In theory, no cutting or welding required. In practice, the factory clamp can be rusted tight and the rubber hangers can fight you for twenty minutes.

Plan for about an hour on a lift, maybe ninety minutes on jack stands. Penetrating oil helps. The right metric sockets help. Patience helps most.

S-Type is what I'd recommend for a tC that gets driven every day. It gives the car a proper note at full throttle without making you shout over it at highway speed.

Borla Multicore race mufflers: what are they, and are they streetable?

Borla Multicore race mufflers come from the track-focused side of the lineup. The name refers to the internal core design: multiple passages inside the muffler body instead of one straight shot. The goal is to manage the sound without turning the exhaust into a restriction.

I'll be straight with you: race is the keyword.

If someone wants Multicore race mufflers for a car that sits in stop-and-go traffic, we ask about noise rules and expectations. A track-oriented muffler is built for abuse and flow, not for quiet commutes. Streetable? Sometimes. Annoying your neighbors at 6 a.m.? Also sometimes.

For shops, that means asking what the car actually does on weekends before you write the order.

Installing a downpipe on a 1.9 TDI: what do I need to know?

Not every question in this FAQ is Borla-specific. This one comes from the 1.9 TDI crowd, and it shows up often enough that I'm answering it here.

Here's the thing: installing a downpipe on a 1.9 TDI is not the hard part. Removing the old one is. The bolts at the turbo outlet have spent years baking and getting salted in winter, so they tend to be stubborn. Soak them with penetrating oil the night before if you can, and use a six-point socket.

You'll also want new hardware and new gaskets on the bench before you start. Reusing the old crush gasket is false economy. And if the car has lived in the rust belt, mentally prepare for one stud to snap. That's not a disaster if you have a bolt extractor set and a few extra hours.

Metric vs. standard socket set: which do I need for exhaust work?

For a 1.9 TDI downpipe, or a Borla system on most Asian and European cars, the answer is metric. Sizes like 10mm, 13mm, 15mm, 17mm, and 19mm cover most of the job.

To be fair, standard sockets aren't worthless. Older American vehicles and some exhaust clamps use SAE sizes. If you can only buy one set today, make it metric. If you work on a mix of vehicles, buy both and keep them on separate rails. Mixing them mid-project is how bolts get rounded.

One warning from my own toolbox: avoid 12-point sockets on old exhaust bolts. Six-point sockets grip the flats. That matters when the bolt is already half rusted away. And yes, I've rounded a bolt with the wrong socket. It's a lesson you only learn once.

No car wash soap: what can I use?

This is a panic I understand. The car is dirty, the bucket is out, and the soap bottle is empty.

Dish soap will work in an emergency. Use a small amount, because dish soap is a degreaser. It will clean the paint, but it will also strip any wax or sealant on top. Nothing breaks. You'll just want to reapply protection afterward.

Don't reach for laundry detergent. It can contain abrasives and brighteners that don't belong on paint. Hand soap can leave a film. Household cleaner is right out.

No car wash soap? Rinse the car well first, use a clean mitt, and dry it before the water spots form. An emergency wash is better than letting bird droppings or tree sap sit while you wait for soap to arrive.

I need a Borla exhaust by the weekend. What are my options?

This is the question that makes my job fun. Someone has a deadline, the cart says estimated delivery, and nobody wants to find out on Monday that the estimate was optimistic.

If you have a hard date, call before you order. We can check what's physically in stock and talk through shipping options that match your timeline.

One June 2024 call stuck with me. A customer needed a Borla system for a truck that had to be ready for a Saturday meet. Standard ground shipping would have had it arriving Monday. One phone call and faster freight fixed the timeline. No drama.

Have the vehicle year and model, the part number if you have one, and the deadline in your head when you call. Earlier calls mean more options. The cart is fine for casual orders. It's not where I'd turn when the calendar is the whole point.