LS3 Medium Bore | Factory Mast | CNC Ported | Cylinder Head - Pair

LS3 Medium Bore | Factory Mast | CNC Ported | Cylinder Head - Pair

Marsoni

M251S

$1572.50

Get it in 3 business days with 1 day shipping. Friday, May 29

LS3 Medium Bore | Factory Mast | CNC Ported | Cylinder Head - PairWe took the Factory Mast LS3 and CNC ported it for even more improvement. Our Factory Mast Cylinder Head starts out with our "as cast" port which we now offer a CNC port for more airflow. This allows for an additional option and price point over our As Cast Port version and our Premium Black Label LS3. ***Download your Cylinder Head Technical Sheet here*** We launched our Factory Mast product line to deliver an economical product line for our

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Exchange/Return Notes

We offer a 30-day return/exchange service after receiving.
Final sale items are not eligible for returns or exchanges.
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The starter was an almost an exact fit. The only difference was the rubber cover for the ground screw. The original started has a slight different design. Easy fix was the remove the old one and replaced it on the new starter. The fit was perfect. Used youtube video on starter replacement for my Sienna which was clear and east to follow. Took 2 hours to replace the starter. Waited a few weeks to see ensure the starter was working before I posted a review. The starter sound strong as the engine kicks over. Looks to be working fine. The dealers would have wanted $600 to replace the started. Some online poster says these Amazon knockoff are cheap and won't work. It started and time will tell how long it last. Its a 25 year old car. If I get another year or two use out of it, I'm good.

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Reviewed in the United States on August 31, 2024

Verified Purchase

Rolondo Jefferson

Belleville, US

★★★★★ 1

Be careful.

Starter arrived broken.

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Reviewed in the United States on April 14, 2026

Verified Purchase

William Russell

Charlottesville, US

★★★★★ 4

Almost a perfect fit for 2002 Avalon

The only difference from the old starter to this one is the old hardware had notches for the electrical connection and the old starter had a longer terminal post so I couldn’t swap the hardware successfully. Instead of returning it because I don’t want to walk to work again I decided to grind a notch on the new starter. Lucky for me it worked and I don’t show up with my uniform sweaty in a retail job anymore

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Reviewed in the United States on August 12, 2025

Verified Purchase

Miguel angel

Charlottesville, US

★★★★★ 5

Motor de arranque

Funciona genial

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Reviewed in the United States on September 20, 2025