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RennTech HHT ECU Upgrade for the 1997-2003 CLK 55: black HHT tuner front view

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RennTech HHT ECU upgrade graphic with the tuner module - RennTech HHT ECU Upgrade for the 1997-2003 CLK 55

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Black HHT suspension module from the plug end - RennTech HHT ECU Upgrade for the 1997-2003 CLK 55

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Black HHT suspension module, rear view with port - RennTech HHT ECU Upgrade for the 1997-2003 CLK 55

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RennTech HHT ECU Upgrade 1997-2003 Mercedes-Benz CLK 55 W208

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Brand: RennTechSKU / Part #: ECU:54.208.CLK55

Regular price: $1,435.60
Regular price: ~~$1,480.00~~
Sale price: $1,435.60
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Subtotal: $1,435.60

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RennTech HHT ECU Upgrade 1997-2003 Mercedes-Benz CLK 55 W208

Subtotal: $1,435.60

Not sure it fits? Text us your VINSee all fitment

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Overview

If you want more from the 1997-2003 CLK 55 without touching the hardware, this RennTech HHT ECU Upgrade is the cleanest way to get it. RennTech revises the factory calibration for this engine, raising power and torque through the full band and keeping the smooth manners the car left the factory with. RennTech rates the CLK 55 at up to 352 hp and 390 lb-ft with this upgrade, a gain of 10 hp and 14 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

What is included

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

Specs

Part number	54.208.CLK55
RennTech rated output	352 hp / 390 lb-ft
Gain (RennTech)	+10 hp / +14 lb-ft

Fitment notes

For the CLK 55 (W208), 1997-2003 as listed by RennTech. Please include your VIN with the order so RennTech can confirm the exact application. Check the fitment table before ordering, and contact us if your car differs.

Fitment

Make	Model	Chassis	Year	Engine
Mercedes-Benz	CLK 55	W208	1997-2003	-

Fitment

Year	Make	Model

Not sure? Text us your VIN and we’ll confirm.

Shipping & returns

Shipping: Orders ship via UPS, FedEx or USPS, from our facility near Los Angeles or directly from the manufacturer. Rates for many items are weight-based and shown at checkout. If you need it by a certain date, text us before you order.

Returns: Unused items in brand-new condition and original packaging can be returned within 30 days of the invoice date, with a 25% restocking fee unless otherwise specified. In some cases we can offer a lower fee with the balance as store credit. Shipping charges aren't refundable in either direction unless approved by AutoTalent.

Not returnable: special-order or custom items, and anything that has been installed, modified or altered.

Cancellations: free if the item is out of stock or we miss the ETA you agreed to. Other cancellations carry a 5% processing fee to cover card fees we can't recover. Special-order items can't be cancelled.

Damaged in transit? Report it to the carrier and to us within 48 hours, keep all packaging, and don't send anything back without our written approval.

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