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Monday 9am - 5pm Tuesday 9am - 5pm Wednesday 9am - 5pm Thursday 9am - 5pm Friday 9am - 5pm Saturday 10am - 2pm

SMG Speed Shop

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United States
Justin, TX
SMG Speed Shop

Old skool speed shop, new skool vibe. Come in talk cars, get expert advice on your build

09/01/2026

🔥 ONE-WHEEL OPEN-BOX STEAL: $149

Forgestar CF5 • 19x9.5 • +29 • Satin Black
Fits listed 2005–2026 Mustang front applications.

Regular price: $485
Open-box price: $149
You save $336 — 69%

One wheel only. It has localized cosmetic rash on the outside lip from transit damage; review every condition photo and verify fitment before ordering. Final sale.

Shop the exact wheel: https://smgspeed.com/products/open-box-deal-forgestar-cf5-19x9-5-29-satin-black-wheel-for-2005-2026-mustang-f21299565p29?utm_source=social&utm_medium=organic&utm_campaign=open_box_rotation&utm_content=forgestar_cf5_149

09/01/2026

HP Tuners has opened direct OBD-II tuning support for the 815-hp Mustang GTD—with no controller upgrade required.

Here’s what the new access means for reading, writing, licensing, supported hardware, and the realities of calibrating Ford’s most extreme road-going Mustang.

Read the full guide: https://smgspeed.com/blogs/news/hp-tuners-mustang-gtd-direct-obd2-tuning-no-controller-upgrade

08/31/2026

A driveshaft can carry 1,200 horsepower and still be wrong for a 150-mph pull. Critical speed depends on length, diameter, material, wall thickness, and RPM—not just the power rating.

Learn how to choose the right aluminum or carbon-fiber driveshaft: https://smgspeed.com/blogs/news/driveshaft-critical-speed-horsepower-rating-aluminum-carbon-fiber-guide

08/30/2026

Boost starts strong, then falls off at high RPM? The cause may be belt slip, heat soak, throttle closure—or more than one at the same time. Here’s how to read the clues and diagnose the real problem before changing parts.

Read the full guide: https://smgspeed.com/blogs/news/supercharger-boost-drops-high-rpm-belt-slip-heat-soak-throttle-closure-guide

08/29/2026

Why do supercharged Coyotes need colder spark plugs—and how tight should the gap be? This guide explains heat range, boost pressure, ignition energy, fuel choice, and the warning signs that tell you the setup needs attention.

Read the full guide: https://smgspeed.com/blogs/news/ford-supercharged-coyote-cold-spark-plugs-heat-range-gap-guide

08/29/2026

671.2 HP on 93 octane. 🔥

Evan’s supercharged 2019 Mustang GT went to North Texas High Performance for headers and a custom tune on the NTHP Mainline Dyno. Final result: 671.2 hp and 585.5 lb-ft.

Built and tuned by North Texas High Performance—give NTHP a follow and message them when you’re ready to turn your Mustang up.

08/28/2026

California lawmakers passed SB 1069, a SEMA-backed bill that could create a conditional sales pathway for qualifying emissions-related aftermarket parts while CARB completes Executive Order review. It does not make unapproved parts street-legal today. Here’s what could change, what would not, and why enthusiasts nationwide should pay attention.

Read the full guide: https://smgspeed.com/blogs/news/california-sb-1069-carb-conditional-sales-performance-parts

08/27/2026

RHS’s new aluminum LS race block is engineered for up to a 4.600-inch stroke, priority-main oiling, and serious Gen III/IV LS combinations. Here’s when a factory LS block stops being the right foundation—and what to plan before ordering one.

Read the full guide: https://smgspeed.com/blogs/news/rhs-ls-aluminum-race-block-4-600-stroke-factory-block-limit-guide

08/27/2026

The C8 Z06 shares about 80% of its engine components with the Corvette Z06 GT3.R. Here’s what that racing DNA means for LT6 intake, exhaust, tuning, and supporting mods.

Read the full guide: https://smgspeed.com/blogs/news/c8-z06-lt6-gt3r-80-percent-engine-performance-mod-guide

08/23/2026

C7 CORVETTE OPEN BOX DEAL 🔥 CORSA 14762 Xtreme valve-back — $1,349 (normally $1,999.99). Save $650.99 / 32.5%. Minor dent; missing clamps and printed instructions. Fits listed 2014–19 C7 applications; verify factory valve compatibility. FINAL SALE. Actual condition photo shown.

https://smgspeed.com/products/open-box-deal-corsa-14762-xtreme-valve-back-2014-2019-c7-corvette

Address

17521 Matany Road Suite 2300
Justin, TX
76247

Opening Hours

Monday	9am - 5pm
Tuesday	9am - 5pm
Wednesday	9am - 5pm
Thursday	9am - 5pm
Friday	9am - 5pm
Saturday	10am - 2pm

Telephone

+19406489812

Website

http://smgspeed.com/

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