Will my GT Steeda Underdrives fit a Mach 1

Mattstang04

15 Year Member
Sep 15, 2006
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St. Louis, MO
I'm gettin rid of my Steeda's for a blower. My buddies got a 03 Mach 1. Can anyone tell me if my GT pulleys will work on the Mach. I know the Machs dont use the alternator pulley. Are the waterpump and crank the same for both vehicles. Thanks.
 
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I saw that too. I wonder if they created a new part number just to sell a kit without an alternator pulley? Not cool. I cant see why they would be different. 4.6L crank should be the same diameter in a 2v or 4v. Bet they use the same balancer bolt too.
 
There are a some differences I believe but the biggest factor is that there have been major issues attributed to running UDPs on the Mach engine.

As copied from this thread on the Mach1Registry Forum: Under Drive Pulleys..and the problems they cause. - 2003-04 Mach 1 Registry Owners Club


Re: Under Drive Pulleys..and the problems they cause.
I'm re-posting this at the end of the thread so people wont miss it.

To put things into perspective, I've been following this topic since 2001. I can plainly state that there has been oil pump failures related to Steeda and other small diameter dampers that are too numerous to count.

First, a brief explanation of what a damper does. The number one priority of the damper is to limit crankshaft deflection, or twist. Each time combustion takes place in the chamber it slams against the top of the piston with the force of a sledgehammer which than slams against the crank throw. This causes the crank to twist or flex a little bit. The further the piston is from the point of resistance (transmission input shaft), the more twist it will impart on the crank. So the front most piston in the engine will twist the crank more than any of the others. The weight of the damper provides resistance against this twisting force and is what prevents the crank from being twisted in two.

The secondary purpose of the damper and the focus of this post is "harmonics". Harmonics is what occurs after the first twist. When the crank twists against the force of the combustion, it then rebounds back the other direction, and then back the other way and so on until the back and forth motion slowly fades away. This creates destructive harmonics that resemble the vibration of a tuning fork.

Let's talk about why these harmonics are more destructive with Cobra’s and Machs and not SOHC Mustang GT’s, 5.0’s, Camaro’s and everything else that is not a high revving DOHC Ford (DOHC BMW's and Imports have also experienced pump failure with small dampers).

1. First are the fragile, powdered metal oil pump gears. They simply cannot take a lot of abuse.
2. Second is the fact that 4 camshafts and all the chains required to run them create a lot of harmonics in the crankshaft. That’s a problem.
3. Third is the steel crankshaft made by Kellog. It’s the kind of crank hot rodders dream of but it’s super rigid and does not absorb harmonics like a cast crank will (automatic Mach 1's have cast cranks).
4. Fourth is the internally balanced short block that is more susceptible to engine harmonics than an externally balanced setup.
5. Fifth is the manual transmission. Gear banging and no fluid filled torque converter.
6. Finally, the death blow for the powdered metal gears: High RPM. The DOHC in stock form performs best when shifted at the factory designated red line, 6800 RPM. Those are some pretty serious revolutions and there are a lot of harmonics created.




All these things combine to make the Ford DOHC oil pump gears uniquely susceptible to failure. As such, the oil pump gears can fail under a variety of conditions that increase crankshaft harmonics. Over revving, forced induction and yes, inferior dampers that do not adequately control harmonics.

Here is a who’s who of the nation’s top modular engine builders that recommend avoiding small size dampers like Steeda on DOHC Ford engines:

Boss 330 Racing. Al Pappito

Modular Performance. John and Mike Tymenski

Accufab Racing. John Mihovetz. NHRA AA/AT World Record Holder

Livernois Motorsports

Pauls High Performance

Sean Hyland Motorsports

VT Engines




Here is small sample of the things they’ve had to say about small diameter dampers:



Quote:
"Do you rev your engine over 6500 rpm? If you do you should worry...The next time you blast through the gears might be your last"
Al Pappito

Quote:
"We do not install small dampers on any DOHC engine builds. All our engines get Innovators West full size dampers"
Livernoise Motorsports

Quote:
"There is alot of harmonic vibration on the front of mod. cranks. The small dia. dampers do not adequately control the vibration"
Al Pappito

Quote:
"The net of all this information is to use the (stock) '96-'01 Cobra balancer (F6ZZ-6312-AB) on all manual transmission, forged crank applications"
Sean Hyland

Quote:
"It appears that if you want your engine to live a happy life keep your stock vibration damper/pulleys"
Al Pappito

Quote:
"Cheapo balancers just do not work with powdered metal gears"
J. Mihovetz

Quote:
"Food for thought..I just rebuilt a '98 cobra it has spent the last five years as a road race car. The bone stock engine had never had a wrench on it, including the rusty stock damper sitting right where it was bolted in 1998. 20,000 mi at full throttle. This thing was totally worn out .guess what....The flats on the crank and the stock pump looked great.
In contrast...A slightly famous Factory stock cobra after a mid season NMRA teardown showed a problem. After 500 street miles and about 35 quarter mile passes the rotors had beat depressions about .040.'' deep into the drive flats where the pump contacts the crank. That engine was wearing a small dia. underdrive damper"
Al Pappito

Quote:
"There also seems to be increased instances of oil-pump failure when some brands of underdrive pulley kits are used. I believe this is due to inadequate damping with the reduced-diameter harmonic balancer"
Sean Hyland

Quote:
"After building truckloads of modular engines a pattern has emerged. Most all oil pump failures involve underdrive pulleys"
Al Pappito

Quote:
"If anyone will spend $5000+ to rebuild an engine, $400 for a damper should be one of the first things. I'm using an ATI"
VT Engines



So let’s review:

If you own a Ford DOHC engine built from 1996 forward, and you rev it over 6500 RPM, every major modular engine builder in the country agrees that it is foolish to run a small diameter damper.

In addition to improper design resulting in numerous engine failures, small diameter dampers have been shown on several occasions to be out of round showing excessive run out when measured with a dial indicator. This is not only poor design but poor manufacturing and quality control. This probably contributes to the vibration many have felt at higher RPM with aftermarket, under drive dampers.



Some guidelines established by the professionals who build these unique engines are as follows:

1. The stock damper with stock powdered metal gears is good to 7,000 RPM.
2. The stock damper with billet gears can operate to 7,400 RPM but is not advisable.
3. Anything over 7,200 RPM should be running billet gears and an ATI damper.
4. A small diameter damper shouldn’t be run in any combination over 6,500 RPM. Billet gears will hold up with a small damper but the harmonics beat up the crankshaft drive pretty good and eventually something will fail whether the pump, a camshaft gear or the crank trigger.





Finally, let’s address some of the arguments presented by under drive, small diameter damper proponents:



Argument 1: “Show me proof!”

Answer: Idiot.



Argument 2: “I’ve run a Steeda small damper aggressively for a long time and have had no problems”

Answer: That’s not impossible. Varying production tolerances will make some oil pump gears more durable than others. Most people don’t want to find out the hard way.



Argument 3: We risk engine damage any time we install an aftermarket performance part on our cars.

Answer: In some cases that may be true but for the most part it simply is not. H-beam rods, forged pistons, hardened oil pump gears, ATI damper, billet oil pump gears, intake and exhaust mods. The list goes on and on. Even things like nitrous and supercharging are relatively safe when applied properly. And the inherent risk in their use is a little more tempting when we’re talking 100+ horsepower gains VS 3 - 5 hp for an under drive damper.



Argument 4: I’ve seen oil pumps fail with stock dampers.

Answer: Sure, it happens. The oil pumps are a marginal design from the factory. Increasing RPM beyond the factory limited 6800 RPM or installing power adders (nitrous, blowers, turbo) are just a couple examples of things that can increase engine harmonics. That is not a reason to install an inferior product that further jeopardizes your engine.



Argument 5: Most oil pump failures can be traced to improper damper installation.

Answer: Not true. What that statement is basically saying is that all the professional engine builders listed above don’t know how to install a damper. I don’t have to point out how ridiculous that is. Besides, it’s one bolt (new) torqued properly. Not rocket science. As a side note TheBlkMach1 had his damper installed by Steeda at their facility. He experienced pump failure with no other contributing factors.



Argument 6: Oil pump failures only occur on race engines or engines that are “over revved”.

Answer: Depends on your definition of “over revved”. Al Pappito plainly states that a small damper engine should not be revved over 6500 RPM. That’s a LONG way from “over revving” a DOHC engine that the factory designed to run at 6800 RPM for hours on end.



Argument 7: Steedas website says they worked with Ford to achieve the proper dampening characteristics.

Answer: That is the standard damper statement they’ve always used. It is meaningless. Fords Technology Transfer Program is available to anyone wanting to build an aftermarket part for a Ford. It can be used to obtain dimensional information as well as many other parameters.



Argument 8: Steeda has a new damper that is as heavy as the stock unit.

Answer: Weight is only one of several factors involved in producing a properly designed damper. The way they’ve distributed a bunch of the weight way out in front does not instill confidence. It's pretty tough to throw caution to the wind and blindly trust this company just because they've covertly admitted to marketing an inferior piece by completely redesigning it and quietly offering it in place of the original unit. Try calling them to ask about it. They wont admit to a re-design. Liability. It only took them 10 years. They haven’t even bothered making any claims regarding improved ability to control harmonics, let alone admitting to a re-design. Guinea pig it for them? No thank you.



In the end it boils down to whether or not 5 hp is worth the risk. Especially when nearly equal performance gains can be had by installing Cobra R pulley’s on the alternator and power steering pump. Even more by adding an electric water pump.

Todd