Product • Support • Tuning
Last updated: August 22, 2026
These Terms of Service ("Terms") govern your use of theefistore.com (the "Site") and any purchase of products or services from Horsepower Connections LLC, doing business as The EFI Store ("we," "us," "our"). By using the Site or placing an order, you agree to these Terms. If you do not agree, please do not use the Site.
We work hard to keep product descriptions, pricing, and availability accurate. Even so, errors happen — a price may be listed incorrectly, or an item may be out of stock by the time you order. If that happens, we'll contact you before charging your card or shipping anything, and you can choose to proceed at the corrected price, substitute a different item, or cancel for a full refund.
Prices are subject to change without notice. We reserve the right to limit quantities, refuse service, or cancel an order at our discretion — for example, in cases of suspected fraud, pricing errors, or a product being discontinued by the manufacturer.
When you place an order, you're making an offer to buy the item(s) in your cart at the listed price. We accept the order once payment is processed and we confirm it — an order confirmation email doesn't guarantee availability. Payment is due in full at checkout.
Shipping timelines, methods, and costs are outlined at checkout. Returns and exchanges are handled through our RMA Request process — see our Refund Policy for full details on restocking fees, timelines, and what is and isn't eligible for return.
In addition to parts sales, we offer EFI tuning, dyno testing, remote/travel tuning, and related services. Performance modifications to your vehicle carry inherent risk. By booking a service, you acknowledge that:
Tools on this Site — including TheEFIBrain chat and the Injector Sizing Calculator — use automated calculations or AI-generated responses to help you plan a build. These are planning aids, not a substitute for a real tune or a licensed tuner's judgment. Always verify safety-critical decisions (fuel system sizing, timing, boost levels, etc.) with a qualified tuner before relying on them — we offer that service ourselves and are happy to help.
You agree not to misuse the Site — including attempting unauthorized access to our systems, scraping content or pricing data, interfering with the Site's normal operation, or using the Site for any unlawful purpose.
All content on this Site — text, graphics, logos, and images — is owned by Horsepower Connections LLC or used with permission, and is protected by applicable intellectual property law. Product images and brand names belonging to the manufacturers we sell remain the property of those manufacturers.
The Site and its content are provided "as is" without warranties of any kind, express or implied, except as required by law. To the fullest extent permitted by law, Horsepower Connections LLC is not liable for indirect, incidental, or consequential damages arising from your use of the Site or our products and services, including damage to a vehicle or engine resulting from modifications, tuning, or installation — whether performed by us or by you.
These Terms are governed by the laws of the State of Arizona, without regard to conflict-of-law principles. Any dispute arising from these Terms or your use of the Site will be handled in the courts of Mohave County, Arizona.
We may update these Terms from time to time. The "Last updated" date at the top of this page reflects the most recent revision. Continued use of the Site after changes are posted means you accept the updated Terms.
Questions about these Terms? Reach us at horsepowerconnection@gmail.com, 928-706-6112, or through our Contact page.
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