GenXTM Street/Strip Cylinder Heads for GM LT1

Thank you for purchasing Trick Flow GenX Street/Strip aluminum cylinder heads for GM LT1. Please follow the stepsoutlined in this instruction manual to ensure that the installationof your new cylinder heads is done correctly and that they per-form according to design.

Please read all of the enclosed information before beginningany work. If you have any questions regarding installation or thewritten materials supplied with your new heads, contact theTrick Flow Technical Department at 1-330-630-1555 for assis-tance, Monday through Friday from 9:00 am to 5:00 pm ET.

PROJECT OVERVIEW

Use this checklist to organize the installation of your new cylinder heads.

Review all paperwork included in the installation packet

Inspect the condition of all components

Verify the quantities of each pr oduct received (see Parts Checklist section)

Mail the warranty card to Trick Flow

Locate recommended tools

Purchase any additional par ts needed (See the Additional Parts Required section—do not pur chase push rods until the pr oper length is d etermined)

Remove existing cylinder heads

Clean and inspect engine block

Check header �tment to cylinder head on workbench

Verify that the temperature sending unit �ts; locate an adapter if needed

Check valve clearance and pushrod length

Purchase the proper length pushrods (see Pushrod Data T able technical bulletin)

Install new cylinder heads on engine

Adjust valvetrain

Make tuning adjustments, perform proper break-in

Test drive and enjoy!

PARTS CHECKLIST

You should have received the parts listed here. Please verifythe part numbers and quantities of each component received.

Two assembled cylinder headsOne instruction packetTwo packs of 5/16" guideplates, four per packTwo packs of 3/8" rocker arms studs, eight per packOne pack of washers , 17 per pack(for use with self-aligning rocker arms)

If you are missing an item or a part was received in error,please contact Trick Flow at 1-330-630-1555, Monday throughFriday from 9:00 am to 5:00 pm ET.

RECOMMENDED TOOLS

Shop manual for your vehicle

Basic mechanics tool set with SAE and metric size sockets and combination wr enches

0-100 ft.-lbs. torque wr ench

Timing light, vacuum gauge, and spark plug gapper

7/16"-14 tap and tap handle

Straightedge

Feeler gauge

Modeling clay

Adjustable pushrod (Comp Cams 7702-1 for hydraulic roller applications, 7703-1 for �at tappet applications)

Solid mock up lifter

Torque angle meter

ADDITIONAL PARTS REQUIRED

These components are required to complete the installation ofyour new cylinder heads. Please refer to the RecommendedComponents chart on the Technical Speci�cations sheet for speci�c part numbers.

Head gaskets Intake gaskets Exhaust gaskets

Head bolts Intake bolts Exhaust bolts

Moly lube Spark plugs RTV sealer

Pushrods Rocker arms Thread sealer

Temperature sending unit adapter (if necessary)

1/2" pipe plug for blocking unused temperature sender hole

Thread locker

Crossover tube washers

Instruction Manual

Installation Instructions

1) PUSHROD AND ROCKER ARM RECOMMENDATIONS

H igh-quality, hardened pushrods must be used in all appli-cations. Trick Flow strongly recommends that you verify thevalve tip wear pattern. Please refer to the Pushrod Data Tabletechnical bulletin for recommendations.

2) CYLINDER HEAD REMOVAL

Consult your shop manual for the proper cylinder head removal procedure for your vehicle. Taking notes, pictures, andeven making a video of the disassembly will help you greatly when reinstalling bracketry and routing vacuum lines.

NOTE: Be sure cylinder #1 is at TDC on the compression stroke.

3) PREPPING THE BLOCK

W ith the old cylinder heads removed, inspect the cylinderbores for scratches, ridges, and cracks. If everything appears tobe OK, put some paper towels in the cylinders to catch loosedebris as the old head gaskets are scraped o� the engineblock’s deck surface. Remove all traces of the gaskets and anyoil or grease that may be present by wiping the surface withbrake cleaner.

Check the deck surfaces for �atness by laying a straightedgeacross the deck lengthwise and sticking a .004" feeler gaugeunder it. If the feeler gauge �ts anywhere under the straight-edge, the block will need to be decked or head gasket failurewill result.

Once the block decks have been cleaned and checked, use a 7/16"-14 tap to chase the threads in the head bolt holes. Thiswill clean out old sealer and debris, which is extremely impor-tant for preventing leaks and torquing the heads down evenlyon the block.

After cleaning the head bolt hole threads, carefully removethe paper towels from the cylinders and discard. Using newpaper towels, clean the cylinders and coat the cylinder wallswith a thin �lm of engine oil to protect them from corrosion.

4) CHECKING HEADER CLEARANCE

Place one of the new cylinder heads on a suitable workstand and install the recommended spark plugs (refer to therecommended Components chart on the TechnicalSpeci�cations sheet for speci�c part numbers). Bolt the head-ers to the cylinder head and check for any interference. Repeatthis procedure on the other cylinder head.

Trick Flow recommends using spark plug wires with 90-degree spark plug boots on header-equipped small blockChevy engines.

4) CHECKING HEADER CLEARANCE (CONT.)

Now is also the time to make sure the vehicle’s temperature sending unit will work with the 1/2"-14 NPT threaded hole inthe cylinder heads. If the vehicle’s sender doesn’t �t, locate asuitable replacement or use an adapter bushing to make thesending unit work (refer to the Recommended Componentschart on the Technical Speci�cations sheet for speci�c partnumbers).

5) CHECKING PISTON-TO-VALVE CLEARANCE AND VALVETRAIN GEOMETRY

If you choose to use the stock camshaft in your engine, andit has not been moved from its factory position, you do nothave to check piston-to-valve clearance. If you have an after-market camshaft or are reinstalling a camshaft (especially witha multi-keyway timing set), you must follow this procedure toassure safe operating clearances between your pistons andvalves:

A) Rotate the crankshaft until the engine is on the compres-sion stroke of the #1 cylinder. Place a solid mock up lifterin the lifter bore of the valve that you will be measuring.Be sure that the mock up lifter is the same height as thelifters that will be installed in the engine later.

B) Coat the top of the piston with a very thin layer of oil,then place a few 1/4" thick strips of modeling clay acrossthe upper half of the piston. Place the head gasket youwill be using on the block and bolt the head on with �veor six head bolts.

C) Install the rocker arm studs, guideplate, and the rockerarm for the valve you are checking (intake or exhaust).Next, set the adjustable pushrod tool to the proper lengthfor your combination (refer to the technical bulletin“How to Optimize Pushrod Length for BetterPerformance” for speci�c instructions). Tighten the rock-er to zero lash, rotate the crank shaft at least twice,remove the cylinder head, and gently remove the clay.

D) Car efully cut the clay into slices and look for the thinnestsection of the valve impression. This impression is a 3Drepresentation of the clearance between the piston andvalve. Carefully measure the thickness of the clay with amachinist’s scale or calipers. The intake valve side of theclay should have .080" or more of clearance, and theexhaust should have .100" or more of clearance. Repeatthe procedure for the other valve.

E) When you are done measuring the second valve, reinstallthe cylinder head in the same manner as before so youcan verify proper pushrod length and valvetrain geometry.The procedure can be found in the technical bulletin“How to Optimize Pushrod Length for BetterPerformance.”

6) INSTALLING THE NEW CYLINDER HEADS

Once the procedures outlined above have been completed,rotate the crankshaft until the #1 piston is at TDC on theexhaust stroke.

NOTE: Reference the maximum recommended valve lift for the valve springs in theTechnical Speci�cations sheet before purchasing an aftermarket camshaft.

With the block deck surfaces and cylinders clean and all checks completed, position the head gaskets on the block per the manufacturer’s markings.

NOTE: Some head gaskets will have “UP” imprinted on one side, while others mayhave “FRONT” imprinted on them.

Don’t be alarmed if some of the holes in the block arerestricted by a smaller hole in the gasket. This is done inten-tionally to regulate coolant �ow. Position each cylinder headevenly on the block’s dowel pins so each head lies �at againstthe gasket.

Next, place head bolt washers over each bolt hole. Oncethey are in place, put a small amount of ARP moly lube on thetops of all washers. Coat all threads with Permatex 3HAviation Form-a-Gasket (follow Permatex’s directions for set-up time), then place the bolts in their proper locations. Torquethe bolts in the three stages shown, following the sequence inFigure 1:

Stage One: Tighten all bolts to 22 ft.-lbs. using a torquewrench

Stage Two: T ighten the long and medium length bolts anadditional 80 degrees using a torque angle meter

Stage T hree: T ighten the short length bolts an additional 67degrees using a torque angle meter

Head bolt retorquing won’t be necessary after initial break-in, but can be done if desired.

NOTE: For head stud installation, follow the head stud manufacturer’s instructions.

7) INSTALLING AND ADJUSTING THE VALVETRAIN

Place the proper length, hardened pushrods into thepushrod holes. Use Permatex 3H Aviation Form-a-Gasket tocoat the base threads of the rocker studs, then put the guide-plates on.

7) INSTALLING AND ADJUSTING THE VALVETRAIN (CONT.)

NOTE: Self-aligning rocker arms do not require guideplates. Instead, use the wash-ers that were included with your GenX cylinder heads in place of guideplates to maintain proper rocker arm stud height.

With everything installed, torque the rocker arm studs to55 ft.-lbs. Place the rocker arms on the studs, and verify thatthey are centered side-to-side. See Figure 2.

Adjust the valvetrain accordingto the camshaft manufacturer’sspeci�cations. If you are using ahydraulic camshaft and no speci�-cations are available, turn the rock-er arm adjusting nuts 1/2 to 3/4 ofa turn past zero lash. For mechani-cal camshafts, you must use thecorrect lash speci�cation deter-mined by the camshaft manufac-turer.

Use the following adjustmentorder for all types of camshafts.This is the easiest method to use since it requires only oneturn of the crankshaft.

A) W ith the #1 piston at TD C on the exhaust stroke, adjustthe exhaust rockers of cylinders #1, #3, #4, and #8, thenthe intake rockers of cylinders #1, #2, #5, and #7.

B) Turn the crankshaft 360 degrees (one full turn) until the#1 piston is at TD C on the compression stroke. Adjustthe exhaust rockers of cylinders #2, #5, #6, and #7, thenthe intake rockers of cylinders #3, #4, #6, and #8.

C) Leave the #1 piston at TDC on the compression strokefor the rest of the reassembly.

8) REASSEMBLING THE REST OF THE ENGINE

Install as many items as you can without putting the valvecovers on. This will allow you to prelube the valvetrain, whichis explained in the Prelubing the Valvetrain section.

Intake Manifold Tips

Apply a 1/4" bead of Permatex Ultra Black RTV sealer tothe intake manifold end rail surfaces. Do not use a gasket onthe end rails, only the RTV sealer. Outline the water openingsat the ends of the head with the Ultra Black to help preventwater leaks. Apply a small amount of motor oil to the intakebolts and torque to factory specs.

Figure 1

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17 9 1 6 14

13 5 2 10

Figure 2

Trick Flow Specialties1248 Southeast Avenue • Tallmadge, Ohio 44278

Sales: (330) 630-1555 • Fax: (330) 630-5565Web: TrickFlow.com

Trick Flow Specialties ® , Trick Flow® , TFS® , and GenXTM are trademarks of Trick Flow Specialties, registered U.S. Pat. O�.

OCT08-032 INSTR SHTTFS-IN-7 Rev. 1

Trick Flow Specialties ® , Trick Flow® , TFS® , and GenXTM are trademarks of TrickFlow Specialties. No license to use or reproduce any of these trademarks orother trademarks is given or implied. All other brands and product names arethe trademarks of their respective owners.

Trick Flow GenXTM cylinder heads for small block Chevrolet are not a product ofChevrolet Motor Division, General Motors, nor are they endorsed by Chevrolet.Trick Flow Specialties is not a�liated with Chevrolet in any manner whatsoever.

8) REASSEMBLING THE REST OF THE ENGINE (CONT.)

Exhaust Manifold/Header Tips

Lay your straightedge across the mating �ange of theexhaust manifolds/headers to make sure they are �at. If theyare not, they will need to be milled �at. Put a small amount ofmotor oil on the exhaust bolts and tighten them down fromthe center out to the ends. This will permit the �ange to betightened evenly. After you run the engine a few times,retighten the exhaust bolts. If the bolts loosen up, the leakingexhaust gas will ruin the gasket.

NOTE: What may sound like a lifter tick is often an exhaust gas leak. Rule outexhaust leaks before tearing the intake o� to replace the lifters.

9) PRELUBING THE VALVETRAIN

The valvetrain is now ready to be prelubed. Start by lubricating the rocker arms, valve springs, and valve stems withabout 1/2 quart of oil per head. Use an oil squirt can to getinside the valve spring and lube the valve stem and seal area.

DO NOT START THE ENGINE IF THE TOP HALF OF THE ENGINEHAS NOT BEEN PRELUBED!

10) VALVE COVER INSTALLATION

The valve cover rails of the GenX c ylinder heads have beenraised approximately .300" to provide clearance for roller rock-er arm polylocks. Adjustments to accessories that mount on orcross over the valve covers may be necessary during reassembly.

If y ou are installing centerbolt-type covers with standard-type roller rocker arms, you will have to reduce the width ofthe oil control ba�es by squeezing them in the center untilthey clear.

11) CROSSOVER TUBE INSTALLATION

The external coolant crossover tube is now ready to bemounted to the rear of the cylinder heads. Using new crossovertube washers, place the crossover tube into position and torquethe mounting bolts to 30 ft.-lbs.

12) BREAK-IN AND TUNING

After the valve covers are installed, reassemble the remain-der of the engine.

To ensure long life and trouble-free use, allow 2-4 hours ofnormal driving time before running the engine hard. This willbreak the valvetrain in properly. If you installed a newcamshaft, change the oil after 30 minutes of operation. Thiswill help to remove small particles that are shorn o� duringthe break-in process. After a proper break-in has been com-pleted, you can use synthetic engine oil.