This Mustang Parts Installation Guide Works For
Installation Time: 2 Hours
Professional Products offers two lines of Harmonic Dampers; POWERFORCE for high performance street applications, and POWERFORCE+PLUS, the SFI-spec line for extreme performance and racing use. The first section of these instructions contains information that applies to all dampers for all types of engines. The basic installation of a Professional Products damper is essentially the same for every vehicle. If the general removal and installation instructions do not apply to any specific application, it will be so noted. Following this opening section, which applies to all installations, there are individual sections which apply to specific types of engines. Each one of these is noted by the vehicle application. Some damper models have unique features that only apply to a specific engine or group of engines. Please carefully read all of the instructions paying particular attention to the sections that apply specifically to your vehicle or engine type. Taking extra time before you start could save you a lot of possible problems later. Some dampers, such as the LT-1, LS-1 GMs, and AMC, have supplemental instruction sheets that apply specifically only to those applications.
Note on Externally Balanced Dampers:Our externally balanced dampers have bolt-in counterweights. The counterweight can be removed allowing the damper to be used on an internally balanced engine. (Except #80001 and #90001. Do not use these dampers without counterweight.) Counterweights are also sold separately and maybe added to use an internal style damper on an externally balanced engine.
Externally balanced engines, such as the SB Chevy 400, SB Fords, BB Chevy 454, Olds, AMC, Chryslers and some BB Fords, have additional weight added to the damper and the flexplate or flywheel to offset the imbalance in the assembly. Some engine builders convert externally balanced cranks to internal balance by adding Mallory metal to the crankshaft. In these instances you would use a neutral balance damper (one without a counterweight) and flexplate or flywheel. Note: Small block Chevy engines have used three different timing pointer locations. Pre '69 engines have the TDC mark 2° to the left of the keyway centerline. The '69 and later dampers have the TDC mark10° to the left of the keyway centerline. All of our SB Chevy dampers, as well as all other aftermarket dampers, use the later TDC position. If you have a pre '69 vehicle you can use one of the aftermarket bolt-on timing pointers to align correctly with the timing marks on our dampers. Use GM bolt-on pointer 3991435 (plain) or 12342000 (chrome) for our6" and 6-3/4" dampers, and GM pointer 3991436 (plain) or 12342011(chrome) with our 8" dampers. Big block Chevys with our 8" damper can use bolt-on GM pointer 3992073 (plain) or 12342001 (chrome).
Other aftermarket companies also make special timing pointers suitable for use with our dampers. The third timing pointer location is on1984 -'95 engines and is at the 12 o'clock position on the damper. Our#80000 and #90000 6-3/4" dampers have a mark for this position.
Small Block Chevy - 60 lb. ft. LT-1 & LS-1 Chevy - 74 lb. ft.
Big Block Chevy - 80 lb. ft.
Small Block & Big Block Ford - 70 - 90 lb. ft.
Mopar - 135 lb. ft.
Oldsmobile - 1964 -'67 Models - 100 lb. ft. '68 & later - 160 lb. ft.
Pontiac - 160 lb. ft.
AMC - 390/401 - 70-90 lb. ft. 304/343/360 - 53-58 lb. ft.
Counterweight Attachment Bolts:
SB & BB 8" Chevy - 18 lb.-ft.
SB Ford - 18 lb. ft.
SB & BB Chrysler - 9 lb. ft.
Olds - 9 lb. ft.
AMC - 9 lb. ft.
All Professional Products PowerForce Dampers (this is all dampers in the #80000 series except the #80010) are made of tough nodular cast iron. Nodular iron is roughly 30% stronger than gray iron which is usually used for all production harmonic dampers and many aftermarket dampers. The PowerForce dampers can safely be revved to higher rpms than a stock damper. However, with safety in mind, please adhere to the listed safe rev limits. The 90000 Series PowerForce+Pus and the 80010 are made of tough 1045 steel and can safely be revved to 10,000 rpm. As part of the SFI testing procedure, our 90000 Series dampers are revved to 12,500 rpm for one hour. However, a static test such as this does not duplicate the loads that are put on the damper in racing applications.
SAFE REV LIMITS
#90000 Series Dampers = 10,000 rpm
#80010 Damper = 10,000 rpm
All other #80000 Series Dampers = 6,500 rpm
Note: These are safe rev limits for the listed dampers. Your engine may not be capable of safely revving to these limits due to other considerations.
All Professional Products dampers are machined to original equipment dimensions and tolerances. If your crank is the correct diameter, your Professional Products damper should fit on the crank with the proper amount of press fit. Unfortunately, some aftermarket cranks and some rebuilt cranks are not made to original equipment specifications. If your crank is too small, the damper will not have the correct amount of press fit. If your crank is too large, it may be difficult to press the damper onto the crankshaft, and in extreme cases, it is possible to split the hub on the damper if the crank is too large. Another problem that may occur at times, is a crankshaft that does not have a deep enough keyway, or a key that is too tall. If the key sits too high in the crank, this can cause serious problems....again the possibility of splitting the hub can occur, which can be an expensive problem. Because our dampers are made to the highest standards, it is highly unlikely for the bore or the keyways on our dampers to be out of tolerance. We have not found this to be a problem, but anything is possible, so we are providing you with the factory specifications for crank diameters and damper bore diameters along with the maximum recommended installed key height. It is always good idea to check all these dimensions before attempting installation. Or, if you run into problems of the damper fit being too looser too tight, these dimensions will let you know where the problems. If the installed key height is too high*, you can grind the top surface of the key down. Some aftermarket cranks may not have the keyway machined deep enough.
This is where you measure the damper keyway depth and bore.
This is where you measure the installed key height and crank snout diameter.
Note: Measure the SB and BB Chevy snout diameters halfway back from end of crank.
|LS1 GM||SB Chevy||BB Chevy||SB Ford||BB Ford||Mopar||Pontiac||Olds||AMC|
|Damper Bore Dia.||1.480/1.481||1.2441/1.2449||1.598/1.599||1.374/1.375||1.374/1.375||1.530/1.531||1.373/1.374||1.498/1.4988||1.3598/1.360|
|Max Installed Key Height||1.654||1.351||1.706||1.462||1.511||1.640||1.469||1.577||1.465|
|Damper Keyway Depth||1.659/1.600||1.356/1.361||1.711/1.715||1.467/1.477||1.516/1.526||1.645/1.655||1.470/1.474||1.582/1.621||1.470/1.480|
Note: All above dimensions are in inches.
IMPORTANT NOTE- If you measure the inside diameter of the damper bore, be sure you get far enough inside the bore to get an accurate measurement.
Several dampers have a larger diameter bore for the first part to make it easier to start the damper onto the crank. Small block Fords have a particularly long lead bore so make sure you are measuring the actual bore that press fits onto the crank. Typically you will not be able to measure this with calipers and will need a telescoping inside micrometer. Our dampers do have lead bores that are the same as the factory specifications with the exception of the small block Ford. These dampers have slightly less than the factory spec in order to provide more contact area between the damper and the crank for high performance applications.
Chevy Crank Snouts: The factory dimensions for both SB and BB Chevy crank snouts specify a slight taper with the nose being smaller than the back part of the snout. The dimensions given above in the chart should be measured at the halfway point of the snout. Applies to O.E. cranks only.
Big Block Ford 429/460 Damper - This damper has two keyways and as a result, there is no practical way to measure the two keyway depths in the damper relative to the bore of the damper. As a result, the dimensions given above for the B/B Ford, while correct for the 429/460 Ford 1/4-inch keyway, cannot be measured with a caliper like the other dimensions that are provided.
Crankshaft Diameters - The dimensions given are, in most instances, original OE factory specs. However, the Pontiac and Olds dimensions were developed through engine specialists who work only with these engines and are accurate to the best of our knowledge.
How to Determine Which Timing Marks to Use - Ford has used more than one TDC (Top Dead Center) timing location. Our small block Ford dampers have three sets of timing marks on them, and one set should align with your pointer. To check this, rotate the crank until the keyway is straight up in the 12 o'clock position. Align the damper keyway with the key in the crank and observe which set of timing marks on the damper lines up with your pointer. (For alternate method, see note 5 on this page.) Once you have determined which marks suit your engine, highlight the degree mark for your initial timing setting (or full advance setting if you power time your engine)with paint or grease pencil. White or yellow will show up best.
|Engine Type||Damper Length||Model Year||Use Spacer||3- or 4-Bolt Pulley|
|289/302/351W||3.050"||1963-'69||No Spacer Req'd||3-Bolt|
|351 HO (351W)||3.875"||1991 & later||#81008 (.875")||4-bolt|
|351W/302||3.875"||1980 & later||#81008 (.875")||4-bolt|
|351W||3.950"||1980-'96||#81007 (.950) or||4-bolt|
|#91007||Steel for blown engines.|
SB Ford Spacer Information - Our SB Ford Dampers are all made to the 1963-'69 length. This allows the use of both early and late style dampers in early chassis. All of our SB Ford dampers also have three and four bolt pulley patterns. They also have three sets of timing marks to suit all SB engines. If your damper is longer than three inches, we make up the difference with a spacer. To determine which spacer you need, measure the length of your damper (see drawing above) and refer to the chart to see which spacer you need. Our standards pacers are made of aluminum and are very inexpensive. If you have a 5.0L engine running a belt driven blower, we recommend that you use our 81009 Steel Spacer.
Adapter Ring- You will find that your damper comes with an Adapter Ring which fits into the front pocket of the damper. This Adapter Ring must be used any time you are using any of the 81000 series Spacers. It also must be used on some of the early three bolt pulleys which require a male pilot sticking out of the front of the damper to locate the pulley. Most early three bolt pulleys fit into a female pocket on the front of the damper. If you are using this type of pulley, you will not need to use the Adapter Ring. It can be easily removed by prying it out with a screwdriver or possibly just pull it out.
Tech Help- For technical assistance, call 323-779-2020 and ask for the technical department.
Big Block Ford - All 429/460 V8s and all 352/390/406/410/427/428 FE V8s
429-460 V8- These engines have used a number of different timing pointer locations. Most engines have the pointer at the "10 o'clock" position looking at the front of the engine. The Professional Products damper has two keyways, a 1/4" and a 3/16"keyway. Using the 1/4" keyway will correctly position the damper on a production crank (or custom crank machined to factory production specifications) allowing the "10 o'clock" pointer to line up with the 0° top dead center mark on the damper. Use the 3/16" keyway with Ford Racing M6303-A600 and B600 crankshafts or on a M-6011-A600 orB600 short block kit. The "10 o'clock" pointer should align with the 0° top dead center mark on the damper.
Note: When using this damper with a Ford M-6303-A600/B600 crank, use a Ford Racing spacer M-6359-C460 over the crank snout before installing the damper. This spacer is used with internally balanced engines only. The stock spacer is Ford part number M-6359-D460 which is used with stock cranks. This damper has the stock four bolt pulley pattern and also the BB Chevy three bolt pattern which allows use of most crank trigger ignition systems or other aftermarket pulley combinations designed for BB Chevy.Adjust pulley alignment by machining the crank spacer as required.
FE V8- These dampers are all neutral balance (no counterweight) although the 428 does use a counterweight on the flexplate, so technically that engine is an externally balanced model. Our FE damper is a duplicate of the stock 427 high performance damper. It is 7.5" in diameter while all other FE dampers are 7" in diameter. Our 7.5" diameter damper can be used on all FE engines. We supply a new timing pointer for the larger diameter. Our timing pointer will fit both early and late FE engines. If your engine uses one v-belt pulley this damper can be used as is. If your engine uses more than one v-belt pulley, unbolt the supplied pulley, and using our supplied aluminum adapter spacer, bolt your stock pulleys in place using the stock bolts. These dampers have both early and late pulley bolt patterns tapped in them so all the stock pulleys will fit.
Small Block Chrysler V8 Engines - All 273, 318, 340 and 360 cid V8s including Magnum.
How to Determine Which Counterweight to use:
Installing the Counterweight - Included with your damper is a small tube of thread sealant. Coat the threads of the two supplied socket head capscrews and attach the counterweight to the back side of the damper into the two appropriate tapped holes. With bolts still loose, push counterweight to the outside of the damper so that the outer radius of the counterweight is touching the inside diameter of the damper. This is important. Tighten the two bolts to 8-9 lb. ft. of torque.
Neutral Balance Engines- Neutral balance means the same as internally balanced. An externally balanced engine has a counterweight on the harmonic damper and a matching weight on the flywheel or flexplate. Internally balanced engines have no offset weight on the damper or flywheel/flexplate.
Some engine builders convert externally balanced engines to internally balanced by adding Mallory metal to the crank counterweights which eliminates the need for the counterweights on the damper or flexplate/flywheel. If you want to do this with your engine, simply use our balancer without any of the bolt-in weights.
Big Block Chrysler V8 Engines - All 351, 361, 383, 400, 413, 426, 440 including 426 Hemi. (Will not fit early Hemi)
How to Determine Which Counterweight to use:
Installing the Counterweight- Included with your damper is a small tube of thread sealant. Coat the threads of the two supplied socket head attach the counterweight to the back side of the damper into the two appropriate tapped holes. With bolts still loose, push counterweight to the outside of the damper so that the outer radius of the counterweight is touching the inside diameter of the damper. This is important. Tighten the two bolts to 8-9 lb. ft. of torque.
Neutral Balance Engines- Neutral balance means the same as internallly balanced. An externally balanced engine has a counterweight on the harmonic damper and a matching weight on the flywheel or flexplate. Internally balanced engines have no offset weight on the damper or flywheel/flexplate. If you, or your engine builder, want to convert an externally balanced engine to internal by adding weight to the crank, simply use our balancer without any of the bolt-in weights.
Special Note: To use this damper on a 426 Hemi requires our pulley spacer#80013 in order for the v-belts to line up correctly.
Pontiac V8 Engines - All 1961 - '79 engines - 326, 350, 389, 400, 421, 428, 455
Note that in order for this damper to fit '61 to '68 engines, you must use a '69or later model timing chain cover, water pump, pulleys and related components.
These parts are available from a wrecking yard or from Year One at800-932-7663. (www.yearone.com). Kauffman Racing Equipment (www.MR-1.com) makes a very nice '69 and later front aluminum timing cover that is very reasonably priced. A similar cover is available from Performance Years.(performanceyears.com) These dampers, unlike some competitive models, have the original Pontiac accessory pulley bolt pattern on them so that your original stock pulleys can be used if so desired. The Pontiac damper is a neutral balance model and essentially the same damper was used on all the various size Pontiac engines manufactured from 1961 through 1979. This damper also incorporates a big block Chevy accessory pulley bolt pattern as well as the stock Pontiac accessory pulley bolt pattern. Some modification tithe pulley or damper hub will be required to use BB Chevy pulleys.
Olds V8 Engines - 350, 400, 403, 425, 455
The Olds harmonic damper fits a wide range of Oldsmobile engines. It is an externally balanced damper with a bolt-in counterweight. As with all of our dampers, if you elect to convert your crank to an internally balanced engine, you can use this damper simply by removing the counterweight. Our Olds damper is dimensionally identical to the stock OEM model except it is made of superior material, has a bolt-in counterweight...which can be removed for a neutral balanced assembly...and also has the stock accessory pulley bolt patterns well as a big block Chevy bolt pattern. The Olds bolt pattern is four5/16-18 tapped holes while the big block Chevy bolt pattern is three 3/8-16tapped holes.
Chevrolet V8 Engines - Small Block and Big Block V8s (Except late LT-1, LS-1 and LS-6. See supplemental instructions)
Our Chevrolet dampers for both small and big block are available in internally and externally balanced models. The basic damper is the same, the difference is the addition of the bolt-in counterweight. If you have an internally balanced model and decide to put it on an externally balanced engine, you can bolt in the proper counterweight (which is also sold separately). Conversely, you can convert an externally balanced damper to internal by removing the weight. Our 6-3/4" S.B. Chevy 350 (#80000 and #90000) and 400 dampers(#80001 and #90001) are too small to incorporate a bolt-in counterweight so they cannot be modified in this manner. While the #80010 damper is suitable for racing applications, it is not an SFI spec damper.
Note:Small block Chevys have used three different TDC timing tab pointer locations. If yours doesn't line up, any of the aftermarket bolt-on timing tabs will provide the correct pointer positioning. See note on first page. We have made a running change in our 6-3/4" SB Chevy 350 dampers #80000 and#90000 by adding another TDC mark which is labeled "Vertical TDC." This is for those engines produced from 1984 to 1995 which have the TDC mark at the top of the balancer and are timed by looking down behind the water pump to view the timing pointer. Use an aftermarket timing tape if desired.
Notes on Balancing
We take pride in the quality and accuracy of the balancing of our dampers. Not only the overall balance, but the accuracy of both the weight and positioning of our counterweights on externally balanced models. We frequently get calls from engine builders and balance shops complimenting us on providing the most accurately balanced dampers they have seen. If you are building a new engine from scratch, and it is a neutral balanced engine (no counterweights on the damper or flywheel) your balance shop can balance your engine without the damper. If it is an externally balanced engine, the balance shop will need both the damper and the flexplate or flywheel to properly balance your engine. There is no need to rebalance a Professional Products balancer.
If you are installing the damper onto an existing engine. and the engine was correctly balanced, your engine will still be properly balanced.
Unfortunately, many of the aftermarket externally balanced dampers being sold today, do not have the counterweight properly positioned nor is the weight of it correct. If you have an existing engine that was balanced with one of these dampers, it is possible that switching to our damper, which is correct, could show up as a problem. Most balance shops will not balance an assembly with these sub-standard aftermarket dampers, so the chances of you having a balanced assembly with one of these dampers is slim. If you do install our damper and have shake or vibration, you will need to rebalance the engine.