SCREAMIN' EAGLE PRO TC PERFORMANCE CYLINDER HEADS

J039632006-07-27

GENERAL

Kit Number

16952-06 (Black) and 16953-06 (Silver)

Models

These kits fit 1999 and later Twin Cam equipped models.

When installed on the following Twin Cam engines the compression ratios are as follows:

Table 1. Engine and Compression Ratio

Engine	Compression Ratio
TC 1450 (with stock bore and stock pistons)	9.5:1
TC 1584 (with stock bore and stock pistons)	10.3:1

These heads are not compatible with Screamin' Eagle Twin Cam High Compression (10.0:1 or 10.25:1) cast pistons.

Additional Parts Required

WARNING

Rider and passenger safety depend upon the correct installation of this kit. Use the appropriate service manual procedures. If the procedure is not within your capabilities or you do not have the correct tools, have a Harley-Davidson dealer perform the installation. Improper installation of this kit could result in death or serious injury. (00333b)

NOTE

This instruction sheet references Service Manual information. A Service Manual for your model motorcycle is required for this installation and is available from a Harley-Davidson dealer.

Table 2. Additional Parts Required

Models	Description
1999-2005 Models	Intake Seal Flange (2) 26993-06
All Models	Top End Overhaul Gasket Kit (17052-99B) and Adjustable or Perfect Fit Pushrods (See Screamin' Eagle Pro catalog)
EFI Models	EFI Race Tuner Kit (See Screamin' Eagle Pro catalog)

Each head requires one 12 mm spark plug.

With Stock pistons, use Screamin' Eagle^® Performance Spark Plugs (32320-91).
With High Compression pistons, use Screamin' Eagle Performance Spark Plugs (32321-91).

All of the above items must be purchased separately and are available from a Harley-Davidson dealer.

Kit Contents

See Figure 2 and Table 3.

INSTALLATION

Cylinder Head Replacement

NOTE

These kits are intended for High Performance or Racing applications only. These engine related performance parts are not legal for sale or use on pollution controlled motor vehicles. This kit may reduce or void the limited vehicle warranty. Engine related performance parts are intended for the experienced rider only.

Due to the increased compression ratio, gasoline with a rating of at least 91 Octane must be used. The Octane Rating is usually displayed on the gas pump.

NOTICE

Do not exceed the maximum safe RPM specified below under any conditions. Exceeding the maximum safe engine RPM can result in equipment damage. (00248a)

NOTE

The valve springs in these cylinder head assemblies work with cams with up to 0.580 in. (14.73 mm) lift, and up to 6500 rpm.

Remove the existing cylinder head assemblies. Refer to the ENGINE section of the Service Manual for all removal and disassembly procedures.

NOTE

It is important to check valve-to-piston clearance as described in the following steps. We recommend that this inspection be performed by a Harley-Davidson dealer.

Valves must be properly adjusted to zero valve lash when claying pistons.

Apply a 1/8 in. (3.2 mm) thick layer of clay to the crowns of both pistons (in the areas where the valves meet the pistons).

Install the new cylinder heads from this kit per the Service Manual procedures, using the new gaskets from the Top End Overhaul Gasket Kit (purchased separately). Assemble the heads and valve train, and tighten the internal-threaded cylinder screws to the torque specifications listed in the Service Manual.

Turn the engine (by hand) through two complete revolutions.

Remove the heads and measure the clay at its thinnest point.

NOTE

Clay must measure 0.080 in. (2.03 mm) at the thinnest point. If this measurement does not meet the minimum thickness, the depth of the valve notches must be increased; however, the depth of the notches must not exceed 0.135 in. (3.43 mm).
Since oversized valves are used, radial clearance should also be checked. Radial clearance of 0.050 in. (1.27 mm) is recommended.

NOTE

The valve springs on these cylinder heads have an installed spring height of 1.820 in. (46.23 mm), which equals 170 lbs (77.1 kg) of seat pressure.

Seat pressure can be increased by placing shims 18224-98 (0.015 in.) or 18225-98 (0.030 in.) under the lower spring collars. Every 0.015 in. (0.38 mm) reduction in spring height equals 5 lbs (2.3 kg) more of seat pressure. Shim to the desired seat pressure by placing shims under the lower collar, but maintain a minimum of 0.70 in. (17.78 mm) travel to coil bind.
Seat pressure can be decreased by machining the surface of the cylinder heads in the area under the valve spring lower collar. Every 0.015 in. (0.38 mm) increase in spring height equals 5 lbs (2.3 kg) less of seat pressure. Machine to the desired seat pressure by machining the spring pockets in the cylinder heads, but maintain a minimum of 0.70 in. (17.78 mm) travel to coil bind.

For constant operation at extreme RPMs, all four valve springs should be checked for matched, installed heights.

1	Upper collar
2	Lower collar
3	1.820 in. (46.23 mm) installed spring height/170 lbs (77.1 kg) spring pressure.
4	Free travel should be at least 0.080 in. (2.03 mm) greater than maximum valve lift.

Figure 1. Valve Spring Travel

Change installed valve spring height (seat pressure) as follows:

a. Compress valve springs and remove valve collar retainers, upper collars, springs, valve seals, and lower collars on all four valves.

b. See Figure 1. Use shims or machine cylinder heads as required to obtain desired seat pressure (see notes above). Install lower valve spring collars (without valve guide seals), valve springs, upper collars, and collar keys. Check installed spring height.

c. If spring heights still do not match, repeat Steps 2a and 2b above as necessary to reach the desired installed spring height, again without installing valve guide seals.

d. When all spring heights match, remove valve collar retainers, collars, and springs. Install using new valve seals 18046-98, purchased separately. Assemble the cylinder head assemblies.

e. Because of the large diameter of the springs in this kit, there may be slight interference between the spring and the rocker box. If interference is detected, the clearance in the rocker box bolts may allow enough movement to gain clearance. If not, it may be necessary to remove a small amount of material from the rocker box.

Install new cylinder heads. Refer to the ENGINE section of the Service Manual for all assembly procedures.

Check assembled engine for proper installation and operation.

NOTE

The compression release plug can be removed for installation of a Screamin' Eagle Compression Release Kit (29298-02).

Recalibrate ECM

NOTICE

You must recalibrate the ECM when installing this kit. Failure to properly recalibrate the ECM can result in severe engine damage. (00399b)

Download the new ECM calibration using the Race Tuner Kit. See Screamin Eagle Pro catalog.

SERVICE PARTS

Figure 2. Service Parts: Screamin' Eagle Pro TC Performance Cylinder Heads

Table 3. Service Parts: Screamin' Eagle Pro TC Performance Cylinder Heads

Kit	Item	Description (Quantity)	Part Number
Kit 16952-06 Black	1	Cylinder head assembly, rear (includes Items 2 through 11)	16948-06
Kit 16952-06 Black		Cylinder head assembly, front (includes Items 2 through 11)	16947-06
Kit 16953-06 Silver		Cylinder head assembly, rear (includes Items 2 through 11)	16951-06
Kit 16953-06 Silver		Cylinder head assembly, front (includes Items 2 through 11)	16949-06
	2	Cylinder head (machined, with Items A, B, C and D installed)	Not Sold Separately
	3	Collar, valve spring, upper (4)	18269-00
	4	Collar, valve spring, lower (4)	18270-00
	5	Stud, exhaust port (4)	16715-83
	6	Intake valve (2)	18045-98
	7	Exhaust valve (2)	18044-98
	8	Seal, valve (4)	18046-98
	9	Valve spring unit (4)	18272-00
	10	Retainer, valve collar (8)	18271-00
	11	Plug, compression release (2)	32069-02
The following service items are available separately:
	A	Valve seat, intake	18049-98
	B	Valve seat, exhaust	18048-98
	C	Valve guide, intake (for service)
		(+ 0.003 in.)	18158-05
		(+ 0.002 in.)	18156-05
		(+ 0.001 in.)	18154-05
	D	Valve guide, exhaust (for service)
		(+ 0.003 in.)	18157-05
		(+ 0.002 in.)	18155-05
		(+ 0.001 in.)	18153-05