LTx Intake Manifold

LTx Intake Manifold — Sheet Metal Body, Printed Bellmouth Runners

Built to order for LT1 / LT4. A hybrid manifold that takes the best of every process: a hand-welded sheet metal plenum for volume and shape, 3D printed aluminum runners with a full bellmouth entry that no welded tube can reproduce, and billet 6061 head flanges that will not warp, move, or leak.

Why Builders Pick This One

• It beat a named competitor on somebody else's dyno. Same car, same day, back to back — 643.0 HP against the MSD Airforce's 636.4 and 625.9 stock. Numbers below.
• It won twice, on two engine families. The same runner architecture on a Coyote beat a ported CJ manifold running a ported CJ throttle body — with an off-the-shelf 80mm throttle body on ours.
• Billet 6061 head flanges — machined, not cast, not printed. The sealing surface is the part that decides whether it holds at boost after a hundred heat cycles. It is also the part most fabricators cheapen.
• The price is on the page, and the hardware is in it. Every other shop building one-off sheet metal at this level makes you call for a number, then bills the flanges on top. Head flange set, throttle body flange, vacuum plate and velocity stacks are included here.
• Built by the man who drew it. One at a time. The person who designed the runner welds your manifold and answers your call.

How It's Built

• Sheet metal plenum body — hand-formed, fully TIG welded
• 3D printed aluminum runners — full radiused bellmouth entries, flowing straight out of the plenum floor
• Billet 6061 head flanges — machined solid, LT1 / LT4 bolt pattern
• Printed aluminum throttle body flange
• Printed aluminum vacuum plate — reference and boost ports integrated
• Port injection ready — injector bosses in place, ready for your rail
• 125mm tapered velocity stacks — the geometry this whole family is built on

Proven On The Dyno

This design lineage was tested at Power Fab Autosports (Spring, TX) on a supercharged 2014 Corvette — Mainline DynoLog chassis dyno, SAE J1995 corrected, same car, back-to-back against the competition:

+17.1 HP over stock. +6.6 HP over the MSD Airforce — and still climbing where the others had already quit. The trade is a few pound-feet down low for power all the way to the top. This plenum is designed to pull to 8,000 rpm; it is only starting to wake up where a stock combination is done. More cam, more boost, more cubic inch, more rpm, and it pulls further ahead.

Second independent test. The same 125mm tapered-stack runner architecture, built as a 5-inch runner Coyote manifold, was run by Cantu Racing against a ported CJ manifold on a ported CJ throttle body. Ours ran an off-the-shelf 80mm throttle body — gave up a little torque low, and made horsepower all the way to the top of the pull.

One more detail that showed up in the datalog: the MAP pickup sits beside the intake port instead of shrouded in the middle of the plenum, so it reads what the engine actually sees — not a low-pressure pocket.

What's In The Price

• Hand-welded sheet metal plenum
• Printed aluminum bellmouth runners with 125mm tapered velocity stacks
• Billet 6061 head flange set
• Throttle body flange
• Vacuum plate with reference and boost ports
• Port-injection bosses

No quote form. No "call for pricing." No line item for the flanges after you have already committed.

Add Fuel Rails — $300

-8 AN anodized aluminum rail set, cut and drilled for this manifold and ready to bolt to the port-injection bosses. Add it at checkout and the manifold arrives complete — no sourcing rails, no guessing at centers, no fitting them yourself. Skip it if you are already running your own.

Choose Your Top

• Sheet Metal Lid — faceted welded top. Lightest, classic race look, fully sealed.
• CNC Billet Lid — machined billet crown carrying the G1Pro script.

Specified At Order

Throttle body size and angle, plenum height, runner length, and injector configuration are all set to your combination. Tell us the build and the RPM band you are chasing — the manifold is designed around it, not adapted to it.

Lead Time

Built to order, one at a time, in sequence. Current lead time is confirmed with your order.

Combination not listed? Message before ordering and we will spec it together.