Cyclone Exhaust Systems - Replacement Parts for Cyclone Exhaust

Cyclone "Shorty Headers"
Replacement Header For Gil Marine, Mercury Hi-Performance & Rex Power Torque Manifolds
Fully Polished Finish

Do your performance manifolds look like these but your stainless steel tailpipes still look like jewelry?  This is a common problem with a number of aftermarket high performance exhaust manifolds, the solution is to replace them with the Cyclone "Shorty"! An all 316L stainless steel header designed as a direct bolt-on replacement for your cast aluminum manifolds. 

By retaining your existing stainless steel tailpipe or riser, you can remove your existing manifolds and simply slide the new "Shorty Header" into place and connect your existing tailpipes.  These units are currently available to replace Mercury Hi-Performance, Gil Marine, and Rex Marine Power Torque manifolds.  Each header is manufactured to the highest quality standard using 100% 316L stainless steel construction, laser machined flanges for a perfect gasket seal, and exhaust tubes that are B.T.B. bent to exact tolerances every time.  A fully welded computer designed water inlet manifold assures equal water flow to each individual exhaust tube.  These headers are completely annealed to maximize durability while preventing corrosion.  CAD-5 technology was used to develop the staggered length exhaust tube runners which provide for broader low and mid range torque, while yielding incredible peak power. This kit comes complete with all necessary bolts and gaskets to attach to your engine. Riser gaskets are not included, and you may need up to 4 gaskets depending on application. See related parts.

Cyclone 525 Standard Dimension Tailpipe - Polished

This tailpipe is used on Cyclone manifolds that are adapted to MerCruiser® 525 engines. It's unique design requires additional hatch clearance in some applications. Consult for information regarding correct fit.

Additional Information:

• Standard Alpha/Bravo Exhaust Hole Locations
• Custom Measurement Instructions

Extreme Duty Hi-Performance D Port Exhaust Manifold Gaskets - 454/502/8.2L Chevy - Sold in Pairs - Replaces OEM Mercury #27-8M0065690

These gaskets are graphite impregnated and designed to withstand the highest of temperatures on high horsepower applications. For those of you looking to do the job only once, insist on Hardin Marine Extreme Duty gaskets. Quite possibly the last gasket you'll ever need. These gaskets are designed to be used in D port Exhaust applications. Replaces stock OEM Mercury #27-8M0065690

Sold in Pairs

• Fits Hardin, Hardin Marine, Power Torque and Mercury Hi-Performance
• Replace your worn out hoses, or have a spare on hand!
• 1" Inside Diameter
• 6-1/2" Center to Center

This kit contains the fittings and bolts to install a pair of manifolds on a big block Chevy Cyclone exhaust system.

This kit contains the fittings, gaskets and bolts to install a single riser on a big block Chevy Cyclone exhaust system.

Extreme Duty Hi-Performance Seaward / Cyclone Exhaust Manifold Gaskets - Stock Square Port 454/502/525 Chevy - Sold in Pairs

These gaskets are graphite impregnated and designed to withstand the highest of temperatures on high horsepower applications. Double drilled for both standard BBC and 525 applications. These gaskets are designed to be used with Hardin Marine's Seaward / Cyclone Exhaust Manifolds. Will work on other Big Block Chevy Manifolds as well. 

Sold in Pairs

We Offer the most complete line of custom fabricated stainless steel fittings available anywhere. All of these fittings are sure to simplify your plumbing job and add a tasteful finishing touch.

We Offer the most complete line of custom fabricated stainless steel fittings available anywhere. All of these fittings are sure to simplify your plumbing job and add a tasteful finishing touch.

316L Stainless Steel Fitting
3/4" NPT Pipe Plug

We Offer the most complete line of chrome plated brass and custom fabricated stainless steel fittings available anywhere. All of these fittings are sure to simplify your plumbing job and add a tasteful finishing touch.

4.0" Offshore Turbulator, Replaces Mercury OEM #816037

Turbulators are designed to keep any condensation or moisture from entering the manifold during the cool down process. This is one of the many unique Hardin features that are helping lead the way in exhaust system technologies. Replaces Mercury #816037. Used with Gil  Style Manifolds and risers.

Hardin Manifold to Riser Gasket, Replaces Mercury OEM# 27-848147

Fits: BBC, SBC and Ford manifolds as well. For Gil Replacement, Mercury HP500 and Cyclone Manifold applications.

Original quality Hardin gaskets are the finest anywhere Their graphite impregnated core assures long life. Depending on application up to 2 or 4 may be required on a single engine. When using a turbolator (See related parts) 4 are required.

These are NOT cheap automotive-style band clamps They are a 100% stainless steel band, clamp, and screw. These clamps are designed to give years of trouble-free service. Don't trust anything but the best for your boat.

• 100-720-6306, use with 3/8" fuel hose
• 100-720-6310, use with 5/8" fuel hose
• 100-720-6312, use with 3/4" water hose
• 100-720-6316, use with 1" water hose
• 100-720-6320, use with 1-1/4" and 1-1/2" Water hose
• 100-720-6328, use with 1-5/8" water hose
• 100-720-6336, use with 2" fuel hose
• 100-720-6352, use with 2-7/8" and 3" Exhaust hose
• 100-720-6372, use with 4" Exhaust hose
• 100-720-6396, use with 5" Exhaust hose