NASCAR (3.4)

What SFI 3.4 Means — And Why It Matters for Custom Suits

Most racers shopping for a NASCAR-style suit run into SFI 3.4 and assume it is a higher protection rating than SFI 3.2A. It is not. SFI 3.4 and SFI 3.2A carry identical fire protection levels — the same TPP values, the same second-degree burn protection times, the same Nomex construction standards.

The difference is in how the suit is tested.

SFI 3.2A vs SFI 3.4 — The Real Distinction

SFI Foundation introduced the 3.4 specification specifically for suits manufactured using modern printing techniques — most importantly, dye-sublimation. When a suit is sublimated, the entire custom design is infused directly into the fire-resistant fabric using heat and pressure. The inks, the printing method, and the finished fabric all have to pass fire testing together — not just the base material alone.

Under SFI 3.2A certification, a manufacturer submits the base fabric for testing. Under SFI 3.4, the manufacturer submits the fabric with the printing process and inks already applied. This ensures the graphic design does not compromise the suit’s fire resistance — which matters enormously for a fully sublimated custom suit where ink coverage is 100%.

If your series rulebook specifies SFI 3.4, an SFI 3.2A suit — even one with custom graphics applied — may not pass technical inspection. The 3.4 certification confirms the complete finished suit, graphics included, meets the fire standard.

Who Needs an SFI 3.4 Suit

NASCAR Pinty’s Series Competitors

NASCAR Pinty’s Series is Canada’s premier touring stock car series. All drivers competing in the series are required to wear suits meeting NASCAR’s fire suit specifications, which include SFI 3.4 for fully printed and sublimated designs. If you are running the Pinty’s circuit, SFI 3.4 is the standard — confirm your specific class requirements in the current series rulebook.

Regional NASCAR-Affiliated Series in Canada

Multiple regional touring and oval series in Canada follow NASCAR rulebook standards or adopt SFI 3.4 as a mandatory requirement for custom printed suits. If your series requires a sublimated design and mandates SFI certification, confirm whether 3.4 is specified — it is increasingly common at the sanctioned regional level across Ontario and beyond.

Any Racer Running a Fully Sublimated Custom Suit in a Series That Requires SFI 3.4

If your sanctioning body or track has adopted SFI 3.4 as the minimum for custom-printed suits, an SFI 3.2A suit with applied graphics will not satisfy the requirement. The 3.4 spec is the only certification that tests the complete printed suit as it will actually be worn.

What’s Built Into Every EPIC Racewear SFI 3.4 NASCAR Suit

Every suit we produce is made to your measurements — not a stock cut adjusted after the fact, but a pattern built from your numbers from the start.

Certified Dye-Sublimation Print

Our sublimation process bonds your design permanently into the fire-resistant Nomex fabric. Colours do not sit on top of the material — they become part of it. This is what allows the suit to pass SFI 3.4 fire testing with the full graphic applied. Your sponsor logos, car number, team colours, and custom design are print-permanent and will not crack, peel, or fade through a full season of racing.

Two-Layer Nomex Construction

The NASCAR 3.4/5 suit uses the same two-layer Nomex base as our SFI 3.2A/5 Lightweight Nomex suit — TPP 19, approximately 10 seconds of second-degree burn protection. The 3.4 certification adds the guarantee that the printing process has not reduced that protection.

Full Custom Fit

• Made to your exact body measurements — chest, waist, inseam, sleeve length, and torso
• 360° arm gussets for full range of cockpit motion
• Stretch panels at high-movement points
• Fire-resistant SFI-rated zippers with FR tape backing
• Reinforced stitching at all stress points
• Cuffs designed to work with SFI 3.3/5 gloves and wrist protection

Complete Sponsor and Design Package

Send us your sponsor logos, car number, team colours, and any design references. We build a full-colour proof before anything goes to print. You approve the design, we produce. No surprises on delivery.

Built in Canada — Shipped to Canada and the USA

Every EPIC Racewear NASCAR SFI 3.4 suit ships from our Walkerton, Ontario workshop. For Canadian teams, that means no cross-border duty, no USD exchange rate, and no waiting on a US customs clearance before your next race weekend.

For US teams competing in NASCAR-affiliated series, we ship directly to your door from Ontario. We also offer a USD product listing for cross-border orders priced in US dollars.

Pair your suit with the rest of your team kit from EPIC Racewear:

• SFI 3.3/5 Racing Gloves — certified hand protection to match your suit
• SFI 3.3 Racing Shoes — fire-rated footwear built to your design
• SFI 3.3 Undergarments — base layer protection certified to SFI 3.3
• Custom Crew Shirts — match your pit crew to your driver for a professional paddock presence

How to Order

Step 1 — Place Your Order

Select your suit above and place your order with a 25% deposit. Our design team contacts you within one business day.

Step 2 — Submit Your Design and Measurements

Send your sponsor logos, team colours, car number, and design references. Download and complete our Suit Measurement Form or watch our measurement guide video first.

Step 3 — Approve Your Proof

We produce a full-colour digital proof showing exactly how your suit will look. You approve every detail before production begins.

Step 4 — We Produce and Ship

Production runs four to six weeks from proof approval. Working around a specific race date? Tell us your deadline and we will confirm whether it is achievable. Ships from Walkerton, Ontario to all Canadian provinces and the USA.

Frequently Asked Questions About SFI 3.4 NASCAR Suits

Is SFI 3.4 better protection than SFI 3.2A?

No. SFI 3.4/5 and SFI 3.2A/5 offer identical fire protection — both carry a TPP value of 19, providing approximately 10 seconds of protection before a second-degree burn. The difference is that SFI 3.4 certification tests the suit with the printing process and inks applied, ensuring the graphic design does not compromise fire resistance.

Does NASCAR Pinty’s Series require SFI 3.4?

NASCAR Pinty’s Series follows NASCAR fire suit specifications, which include SFI 3.4 certification for fully printed and sublimated suits. Confirm the current requirement in the series technical regulations before ordering.

Can I use an SFI 3.2A/5 suit with custom graphics for NASCAR racing?

If your series specifically requires SFI 3.4, an SFI 3.2A suit — even one with custom sublimated graphics — may not pass technical inspection. SFI 3.4 is the only certification that tests the complete printed suit as worn. When in doubt, confirm with your series technical director.

How long does a custom SFI 3.4 suit take to produce?

Four to six weeks from proof approval for most orders. If you have a specific race date, let us know at the time of ordering and we will advise on timeline.

Does EPIC Racewear ship NASCAR SFI 3.4 suits to the USA?

Yes. We ship from Walkerton, Ontario to all US states. See our USD product listing for cross-border orders priced in US dollars.

Can I see design options before ordering?

Yes. Visit our suit designs gallery for design inspiration, or contact us and we will build a custom concept for your review before you commit.