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RennTech HHT ECU upgrade graphic with the tuner module - RennTech HHT ECU Upgrade }
RennTech built its name in Florida tuning high-performance engines, and this HHT ECU Upgrade for the 2003-2006...
Vendor: RennTech
SKU: ECU:54.230.SL600o
Product Type: ECU Hand Held Tuner
Regular price
$1,891.50
Regular price
$1,950.00
Sale price
$1,891.50
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RennTech HHT ECU Upgrade 2003-2006 Mercedes-Benz CL / S / SL 600
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RennTech built its name in Florida tuning high-performance engines, and this HHT ECU Upgrade for the 2003-2006 CL / S / SL 600 is the result of in-house dyno development on the 5.5L M275 twin-turbo V12. Timing, throttle, air-fuel and boost tables are revised as one calibration, so the car pulls harder everywhere while staying a comfortable daily driver. RennTech rates the CL / S / SL 600 at up to 625 hp and 745 lb-ft with this upgrade, a gain of 133 hp and 155 lb-ft.

Watch it explained

Features

  • Loaded through the RennTech HHT hand-held tuner via the OBD2 port, no ECU removal
  • The HHT stores the tuned and the factory file, so you can switch back to stock any time
  • Revised ignition timing, throttle mapping, air-fuel ratios and boost control
  • Gains across the entire rev range, not just at peak
  • Developed on RennTech's own dyno and road tested
  • Keeps factory-like drivability and reliability for daily use
  • 93 octane or better recommended for the full calibration

What is included

  • RennTech calibration for your car
  • Delivery as listed by RennTech for this model (HHT tuner or ECU flash)

Specs

Part number 54.230.SL600O
Engine 5.5L M275 twin-turbo V12
RennTech rated output 625 hp / 745 lb-ft
Gain (RennTech) +133 hp / +155 lb-ft

Fitment notes

For the CL / S / SL 600, 2003-2006. Please include your VIN with the order so RennTech can confirm the exact application. The full calibration needs 93 octane or better fuel. Check the fitment table before ordering, and contact us if your car differs.

Fitment

Make Model Chassis Year Engine
Mercedes-Benz CL / S / SL 600 - 2003-2006 5.5L M275 twin-turbo V12

If you have any fitment questions, please feel free to reach out to our team via the contact methods below. If you are contacting us for any order status updates, please give us a call, or email us. We are a lean operation bringing you the best shopping experience possible. We are working on your orders as quickly as we can. We thank you for your patience.

Call:
Please reach out to us at (310) 231-0292 for sales inquiries if you are in the United States, Canada, Mexico.
Email:
For more in-depth product questions, fitment questions, product inquiries please email our performance specialists at online@autotalent.com.
All other inquiries:
Please direct your inquiries to the chat functionality on our website.

Returns Policy

If a product is ordered and not wanted, the UNUSED item can be returned for a 25% restocking fee unless otherwise specified. In some cases, we may offer the ability to return the item to us for a lesser restocking fee and then keep the balance as a store credit. To return an item, it must be in brand new condition with original packaging.

We cannot accept a return on special ordered or custom items.

Shipping is non refundable in either direction unless approved by AutoTalent. All items wanting to be return MUST be reported within 30 days of the original invoice date. No items will be returnable after 30 days. All products shipped from the AutoTalent facility are shipped via FedEx, USPS, or USPS. Some packages shipped from the manufacturer may or may not require signatures for package release.

Special Order Items

Some items may be special order specifically for the customer’s vehicle. These items generally require a deposit or paid in full. Once this deposit amount is notified to the customer and they agree to order the special order item, the deposit becomes non-refundable. These special order items cannot be returned or resold. Cancellations are not allowed on special order parts.

AutoTalent DOES NOT REFUND SHIPPING CHARGES. If you modify, install, or alter the item in any form, we cannot accept it as a return. We will not cover any expenses related to the product or installation, and you may be required to purchase a replacement.

** All cancellations that are requested that are NOT due to items not being in stock or delayed by the manufacturer are subject to a 5% processing fee. When you place an order with us we pay credit card fees that are NOT returned back to us. We will absorb these fees if we do not have the item in stock OR if you agree to the original ETA and that ETA is NOT met. If you decide to cancel for any other reason you will not receive this 5% fee back

Shipping

We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations.

When you place an order, we will estimate shipping and delivery dates for you based on the availability of your items and the shipping options you choose. Depending on the shipping provider you choose, shipping date estimates may appear on the shipping quotes page.

Please also note that the shipping rates for many items we sell are weight-based.

Fitment
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