Name: T4 Twin Scroll Manifold & 3" Exhaust for BW EFR 6258/6758/7163 Turbo - Kraken Miata MX5 Performance
Availability: InStock

T4 Twin Scroll Manifold & 3″ Exhaust for BW EFR 6258/6758/7163 Turbo

Cast NiResist D5S Type 2 twin scroll turbo manifold with 3″ downpipe and full exhaust for MX5 and Miata. Designed for BorgWarner EFR T4 IWG turbos (6258, 6758, 7163). True 1-4 / 2-3 scroll pairing, 38mm ID runners, internally gated, AC compatible. Exhaust is hand-made from 304L stainless steel with Swedish-made Simons resonator and muffler.

Engine size

Chassis Type/Year

200 Cell Metallic Catalytic Converter

Clear

Guaranteed Safe Checkout

Description

This kit includes the twin scroll turbo manifold, 3″ downpipe and full 3″ exhaust.

Twin Scroll Turbo Manifold

Cast from NiResist D5S Type 2, a high-nickel austenitic cast iron that resists cracking under sustained heat and repeated thermal cycling far better than stainless fabrications or standard cast iron. This is not cheap material and it is not easy to cast, which is why these manifolds come with a 5 year unlimited warranty.

Runners are paired 1-4 / 2-3 to keep exhaust pulses separated between the two scrolls. This preserves pulse energy at the turbine wheel, improving spool and response right through the rev range. With 38mm ID runners, this manifold flows enough to support 600hp+. Internally gated through the EFR’s built-in wastegate, so no external gate to package. Fits with AC in place.

3″ Downpipe

3″ V-band connection to the turbo with a tight radius bend to clear the chassis. Made from 304L stainless steel elbows and pipe, TIG welded throughout. The tight radius bend is made from pie cuts and back purged. Space is limited and the downpipe sits close to the brake lines. You will need to bend/wrap the brake lines. This is the same for most turbo systems and doesn’t create any issues.

3″ Full Exhaust

Hand-made, straight-through design using 304L stainless steel throughout, TIG welded with V-band connections all the way. The muffler, resonator and 200 cell metallic cat are made in Sweden by Simons Exhaust Systems.

Simons part numbers:

Muffler: U327663R
Resonator: U457600R
200 Cell Metallic CAT: UK0376AR (optional)

The exhaust does not come with a cat as standard. You have the option to order a cat and decat pipe with the exhaust, otherwise it ships as decat with a straight pipe where the cat would sit. To add a cat afterwards the exhaust will need to be cut, so order the correct configuration from the start. The cat is sold at trade price.

What’s in the Kit