Installation instructions

Parts that need instructions ship with them in the box. If yours is missing, or you want to read it before you buy, send us the part number and we will email the guide.

Before you start

Check the part number on the box against your order.
Read the fitment notes on the product page and compare them with your engine.
Have a torque wrench and the correct thread sealant or gasket maker ready.
Use the compression calculator when changing heads, pistons or gaskets.

After you finish

Re-check torque after the first heat cycle, and look for leaks before driving. If something does not fit as it should, stop and contact us before modifying the part, as modified parts cannot be returned.

Performance and aftermarket parts

Performance parts, shipped today.

0 parts for Chevy, Ford, GM LS and Mopar builds, from gaskets to crate engines. Free shipping on orders over $150.

Today's deals Popular: Intake manifolds Cylinder heads Ignition kits Superchargers

Free shipping over $150Same-day dispatch before 3 pmTrack every order onlineMilitary & first-responder pricing

Today's deals

Special pricing, while stock lasts.

See all deals

Shop by department

Everything between the bumpers.

Eight departments, with fitment notes on every part and a part number you can reorder by.

Quick links

Intake manifolds Downdraft manifolds Complete cylinder heads Ignition kits Roller rockers Install instructions

The store

On the shelf right now.

Best sellers, special pricing, clearance and outlet stock. Everything marked in stock ships today.

Full catalog

Browse every department.

0 parts across eight departments. Pick a category, filter by engine, sort by price, and open any part for a closer look.

Matched on our bench. Ready to fit.

Crate engines, top end kits, supercharger kits and ignition systems assembled and checked before they ship, so every component arrives already working together.

Fig. 1 · 6-71 roots blower9.5 psi at 6,000 rpm

More ways to save

Outlet, offers and discounts.

Outlet store

−40% up to

144 refurbished and clearance parts

Open-box returns and end-of-line stock, inspected and covered by the same warranty.

Shop the outlet Special pricing

0parts reduced

Special pricing

Reduced prices across every department while stock lasts.

See the offers Military & emergency services

10% every order

Thank-you pricing

Verified service members, police, fire and ambulance crews save on every order, on top of rewards points.

Verify once

Merchandise

Gear for the shop floor.

Motor Base apparel, drinkware, signage and gifts, in the same black, red and gold as the store.

Rewards

Every dollar builds your status.

One point per dollar, double and triple on selected parts, across seven tiers from Red to Black. Once you reach a tier it holds for a full year, and Gold and above get a dedicated account manager.

Spend this year

$3,400

3,400Points

$2,600To next tier

Your tier

Yellow

Test drive game

Pick a car. Drive the city.

Take a supercharged muscle coupe, a big-block classic, a V8 pickup, a turbo rally sedan or our concept car for a spin around a 3D city. Every car has its own engine sound, gearing and grip, and you shift with a real clutch.

Optional and free. The game only loads when you press play. Open it full screen.

Complete automobiles, built to order

Tools & resources

Measure twice. Order once.

Install guides, catalogs and engine calculators. The calculators are pre-filled with a typical 350 small block.

Installation instructionsSearch a part number, or ask us to email its install guide. CatalogsBrowse every department online, or ask for a printed copy. CalculatorsCompression ratio and trap-speed horsepower, below.

Cart