Brakes› Master Cylinders-Boosters and Components

Nismo

13/16-inch Bore Master Cylinder

$270.00

SKU: 30620-RSR40

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

It replaces the stock 3/4-inch cylinder with a larger 13/16-inch bore.
Show original supplier description
By increasing the internal cylinder diameter from the OEM 3/4 inch (19.055mm) to 13/16 inch (20.54mm), this unit reduces pedal pressure by 14% and improves half-clutch operating characteristics. It is specifically intended for use with pull-type clutch configurations, providing proper engagement positioning. Installation requires specific care to maintain performance. Because the cylinder stroke volume is reduced compared to the standard part, adjustments to the stroke are often necessary. Users must ensure that no air enters the system during installation; clamping the hose securely is required before removing the old cylinder. It is recommended to fill the cylinder with brake fluid and bleed it thoroughly before final connection. Vacuum pressure is suggested for complete air removal, particularly when using wide-diameter pipes such as the U-pipe; using a U-pipe eliminator adaptor is recommended for this purpose. A copper seal washer (Genuine Nissan part 46237-A4600) is required for installation.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandNismo
Part Number30620-RSR40
CategoryBrakes
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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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