V6 underdrive pulleys

[spindlecone]

Can now be had for the SOHC V6,Crank pully and damper complete, $285.00.
20% underdrive= 16 Dyno proven RWHP H.P on the 4.0 V6 Mustang.
Same engine as used in the Ex, same pulley.
www.aspracing.com.
May have more info in a couple days on a sporttrac install.

 

[jah81592]

Muscle Mustangs And Fast Fords had ASP in their advertisers new products in the Dec issue. I am waiting for someone else to come out with a complete set. Thanks for the info I failed to let you guys know. I get so wrapped up in Mustangs I assume you guys are aware of some of the new products coming down the pipeline for the 4.0L!

 

[aldive]

I shall be obtaining a set of these pulleys shortly to evaluate their effect on gas mileage,

 

[spindlecone]

I shall be obtaining a set of these pulleys shortly to evaluate their effect on gas mileage,

Complete set do's not exsist yet, just the crank pully and damper.
BTW the same pully also fits the V6 OHV engine according to the manufacturare

 

[ExplorerDMB]

Interesting...might be worth looking into

-Drew

 

[aldive]

On another web site, I found a post about install of underdrive pulley on a 4.0 SOHC ( on a Sport Trac ).

Take a look at http://www.mysporttrac.com/shared/msgboard9e.asp?BOARDNAME=MSG&VIEW=801701

 

[spindlecone]

On another web site, I found a post about install of underdrive pulley on a 4.0 SOHC ( on a Sport Trac ).

Take a look at http://www.mysporttrac.com/shared/msgboard9e.asp?BOARDNAME=MSG&VIEW=801701

Thats my Buddy Todd
Can't wait till he Dynos again with the Pully. The guy is making 228.5 RWHP pre pully (and yes I have seen his charts)

 

[spindlecone]

Al
He got the pully here:www.aspracing.com

 

[JDraper]

Do you happen to know if the oil pump gear on the 4.0 is made from powdered metal or a regular steel grade? Reason for asking is that the gear on the 4.6 DOHC motor is powdered metal, and there has been an extremely high failure rate in the gear with motors that have an underdrive pulley/aftermarket damper installed...

 

[aldive]

Do you happen to know if the oil pump gear on the 4.0 is made from powdered metal or a regular steel grade? Reason for asking is that the gear on the 4.6 DOHC motor is powdered metal, and there has been an extremely high failure rate in the gear with motors that have an underdrive pulley/aftermarket damper installed...

Interesting.

 

[JDraper]

The belief is that the underdrive pulley/balancer combo on the DOHC 4.6 alters the harmonics in the bottom end of the motor and this causes the gear to break. It hasn't happened in the Cobra motors which have the billet gear, or the SOHC 4.6 (I don't know what type of gear is installed in the SOHC), only in the DOHC Mach motors with the powdered metal gears. The failure rate has been extremely high (like 90%).

NOTE: I'm not saying this will happen with the underdrive setup listed above, just that it has occurred in at least one of Ford's OHC motors.

 

[aldive]

Jeff, are you running underdrive on your 'stang?

 

[aldive]

Further, Jeff, are they failing in high rev racing applications? or on the street?

 

[JDraper]

I am not running underdrive anything on my 'Stang.

The failures have happened on both the street and at the track. Again, I can't speak for the 4.0 and how it will respond to underdrive pullies/damper. It may work perfectly well and never have a problem.

The pullies alone are not the problem on the 4.6 motor. From what I have read/seen, it is more the damper than the pullies. I have not heard of any vehicles that have had failures with only underdrive pullies, it's only the ones with the aftermarket damper/pulley combo that have failed.

If you look on the site that Spindlecone provided, it shows underdrive equipment for just about every vehicle except the Mach, so it may only be Mach related.

I asked the original question about the sintered vs. machined gears because I (and others) believe that the problem lies with the gear, not the pullies. I think that the sintered gears are not as strong or durable as the machined gears, and the change in motor harmonics that the underdrive pully/damper combination cause just excaberates the problem. If the 4.0 SOHC has a machined oil pump gear, I would have no qualms about installing an underdrive system.

 

[spindlecone]

How can you tell a sintered gear from a machined gear, is there a visual diff?

 

[aldive]

The following is a good install article - http://underdog-performance.com/id97.html

 

[spindlecone]

Good Read

 

[JDraper]

How can you tell a sintered gear from a machined gear, is there a visual diff?

Usually a sintered part (when new) will appear slightly more granular, and you don't get a smooth machined surface like you would for a machined gear. It will also lack any machining marks, as they are formed through a molding process, not machined. It is also possible to see grain boundaries more often in sintered gears. Ultrasound is one of the most accurate ways to tell. Because of the granular structure, sound scatters very quickly in sintered metals whereas it transmits quite well through conventional steel.

I develop both Ultrasonic and Eddy Current (electromagnetic) test equipment for a living. We work extensively with the powdered metal industry in creating equipment and procedures to test powdered metals for flaws before they are installed. Powdered metal parts are very desirable to the manufacturers because it is much easier to create complex geometries in a cost effective way, and they are very durable when properly compacted and sintered. However, it is not always advantageous to use sintered metal components as their properties are slightly different than either cast or forged metals.

 

[spindlecone]

Thx D
Where on the 4.6 is this gear located? do not understand the relationship of the oilpump gear and the crank pully and damper

 

[JDraper]

IIRC, the gear is driven off the rear of the crankshaft. From what I understand, the aftermarket dampers cause a change in the crankshaft harmonics, which generates vibration in the gear, leading to failure. There have been several heated discussions on this over on the Mach boards, and the consensus is, stay away from underdrive pulley/damper combos on the Mach motor. As with anything, there are a couple people that swear by them and claim never to had a problem, but most that have gone to underdrive setups have eventually broken the gear.