Harmonic Balancer Question

[Ben99GT]

Is that true with 4.10's or is it more applicable to the stock 3.27's? I personally never noticed where the RPMs drop to when I shift from 1st to second, I'm usually concentrating on the road ahead of me and just being mindful of the RPMs in corner of my eye. That's one of the reasons I got a Raptor shift light. When you are on the autocross grid or road course its a bit more difficult to make sure you are shifting at exactly the optimal RPM since you are trying to coordinate an process so much. I'm sure it gets easier with seat time, but for my experience level it is still a demanding task.

It's still true with 4.10s. The high rpm shift is most critical on the 1-2 shift because of the 3.37 to 1.99 gear drop, that creates a big RPM drop. The 1-2 needs a good 6800-6900 rpm shift.

The 2-3 and especially the 3-4 don't need to be quite as high because the gear spacing is closer. You still need to shift well past peak power though.

 

[cobraetti]

The reason I keep citing the 6500 rpm number is that unless you have a ported/worked intake, head work or non-stock cams and valve springs there is no reason to spin the motor any higher. Every single dyno sheet I have seen from people that make in the 300 whp area with bolt-ons the power peaks around 6200 rpm and is clearly dropping off at 6500 rpm. If that is indeed the case why would you continue to rev past that point? There is no benefit to be had by doing so, you are just tempting fate no matter what damper you are running.

Now answer honestly, do you have a problem with the March 1158 damper (which is smaller and has less rotational mass than the new Steeda part)? Or do you only get all nasty on this subject because Steeda used re-branded ASP pulleys over 5 years ago that may have contributed to some of these failures. Be honest and tell me if you can provide a link or anything else that specifically links Steeda's new design to these failures. And no, I will not accept some quote from 8 years ago that only uses the generic term "small diameter damper".

whats the opinion on the march 1158(fluid damper)?

 

[na svt]

whats the opinion on the march 1158(fluid damper)?

a damn good piece

 

[Tarball]

whats the opinion on the march 1158(fluid damper)?

Thats what I run.

 

[tmhutch]

whats the opinion on the march 1158(fluid damper)?

Never heard of any problems with it.

 

[tmhutch]

Now answer honestly, do you have a problem with the March 1158 damper (which is smaller and has less rotational mass than the new Steeda part)? Or do you only get all nasty on this subject because Steeda used re-branded ASP pulleys over 5 years ago that may have contributed to some of these failures. Be honest and tell me if you can provide a link or anything else that specifically links Steeda's new design to these failures. And no, I will not accept some quote from 8 years ago that only uses the generic term "small diameter damper".

You're just not getting it. Whether yesterday or yesteryear, good information doesn’t suddenly turn bad. There is no "may have contributed" about it. Steedas are uniquely responsible for several engine failures. You seem willing to learn but you’re very stubborn.

I’ve spent the last 8+ years reading every thread ever posted on the subject but I’m not going to waste my time conducting searches you are too lazy to do yourself. It should be obvious that there is plenty of information provided in this thread alone for anybody to make an intelligent decision.

I’ve not heard of any failures with the March unit. It’s fairly new and somewhat untried but NA SVT has been running the hell out of one for awhile and seems to like it. The concept is that the fluid compensates for the lost harmonics inherent in its smaller size. The only bad thing about fluid filled dampers that I know of is that after a number of years the fluid starts to solidify, and that creates a serious problem. Maybe the new ones wont do that. I don’t know.

As for the piggyback units, they’re not ideal because there is the potential for balance issues. However, they retain the proper mass and diameter to control harmonics and that’s the important part. Improper balance can rob horsepower and wear out bearings a little faster but it’s a completely different issue from harmonics which can be thought of as a vibration issue as opposed to a balance issue. Harmonics, not balance issues, kill oil pump gears.

I will give a little perspective why you don’t see a lot of blown oil pump posts. The issue with the dampers started coming to light early 2001. Stangnet was the big forum back then and there were a lot of posts once people started connecting the dots. By 2003 most people knew better and very few small dampers were being installed on DOHC cars. The few people who were installing them knew of the controversy. Occasionally some would come clean if their pumps shattered but most were busy popping off like you two and would take their blown engine secret to the grave rather than humiliate themselves on a public forum. If you look at the join dates for the people who generally argue about dampers you’ll see they are fairly recent. They’re usually quite young or people who have been driving 5.0’s and SOHC’s for years and just recently purchased their first DOHC car. They weren’t around when all this went down and after a couple years on the boards and not seeing a bunch of failed damper threads they think they’re smarter than everyone else.

DOHC cars account for less than 3% of the Mustangs sold each year. Most guys arent out there modifying and driving the crap out of them like we are. The people on these boards account for a very, VERY small minority of Cobra and Mach 1 owners. Of this very small percentage, an even tinier group of people have been foolish enough to bolt Steedas on their DOHC’s. I guarantee you “1000’s” of steeda’s aren’t being run on Cobras. When one of these do fail, it’s not like we’re going to hear about it. As far as the ones that don’t fail, maybe they feel the same way you do. That theres no reason to shift beyond 6500 RPM. We just can’t know the intimate driving details of every Cobra/Mach owner.

And you keep referring to Steeda’s redesign. Since you seem to be impressed with steeda’s claim that “Our underdrive pulleys are the only pulleys engineered through our unique partnership in Ford's technology transfer program to have the proper torsional vibration dampening characteristics for your 4.6L engine.” I’ll explain to you what that means. Fords “technology transfer program” is available to any manufacturer needing engineering and design parameters to properly produce an aftermarket product. It means that Steeda finally pulled their head out there a$$ and asked Ford how to build a damper that doesn’t blow up engines because they couldnt figure it out themselves. It means very little. It doesn’t guarantee their production tolerances have been improved. It doesn’t mean the damper is properly designed. And there still is NO accountability from steeda on this part. But I’ve already addressed this ad nausea. No company that knowingly blows up engines for 8 years will get my business.

Guinea pig their new, almost properly designed, experimental wiz bang damper if you want. Just be honest with yourself. What are you really getting from it? 3 horsepower, improved appearance on a part rarely seen? At some point some of this will have to sink in. Don’t let this turn into an argument your ego has to win.

 

[na svt]

This topic comes up about once a week and can be debated for the next 20 years. Todd, Ben, Mark and I have seen this same question come up numerous times the past few weeks and rarely have any opinions been changed. All I can say is due some searching for yourself and make a decision based upon what you've found.

So fellas, how about a discussion on throttle bodies or 3.73 gears?

 

[Tarball]

How much oil does the 4.6 take?

 

[OzzDOA]

To be honest I got a 9 hp and 11 trq increase at the wheels from the Steeda pulleys, did a baseline run before and after the install. Being an engineer by trade I took a really good look at the Steeda damper before install. To be honest I was concerned about them and wanted to be 100% sure I was comfortable with installing the part. Externally it appears to be constructed in the same manner as the stock Ford damper. An inner pulley component, layered with a rubber harmonic damping ring (which is 50% thicker than the stock piece, I measured) and finally an outer ring which provides the vast majority of the rotational mass and inertia. While I have no idea of the actual manufacturing process or tollerances it appears to my eyes to be an adequately engineered product which uses the design of the stock part as a basis for improvement. Now I have my engineering/physics education, several weeks of searching the forums and reading on this exact subject and the opinions of tuners and builders that I trust which contributed to my decision. What do you have? 8 years of reading the interwebs?

In response to my other question, I did a little experiment last night and this morning and really payed attention to the drop in RPMs produced during the 1-2 shift. After a sample of 40 shifts (my typical street granny shifts to boot) the average RPM drop on the 1-2 upshift was 1500 RPM. So looking at my latest dyno sheet, I can extrapolate that by shifting at 6500 RPMs (really its more like 6600-6700 by the time I actually shift) it would place me in the 4000 to 4200 RPM range. This RPM range is within 7% deviation from my peak torque and 29% deviation from peak horsepower. A couple hundred more revs is maybe worth a 3 or 4% increase in power and torque in relation to peak numbers. I'm sure it makes more of a difference on more built/powerful engines but for me the advantage of shifting later (past 6500) in the RPM band is effectively minimal to none.

 

[Ben99GT]

What are you really getting from it? 3 horsepower, improved appearance on a part rarely seen?

I cleaned up my stock damper and threw a coat a flat black on it, now it looks about as good as the Steeda damper. :burnout:

 

[Ben99GT]

I did a little experiment last night and this morning and really payed attention to the drop in RPMs produced during the 1-2 shift. After a sample of 40 shifts (my typical street granny shifts to boot) the average RPM drop on the 1-2 upshift was 1500 RPM. So looking at my latest dyno sheet, I can extrapolate that by shifting at 6500 RPMs (really its more like 6600-6700 by the time I actually shift) it would place me in the 4000 to 4200 RPM range. This RPM range is within 7% deviation from my peak torque and 29% deviation from peak horsepower. A couple hundred more revs is maybe worth a 3 or 4% increase in power and torque in relation to peak numbers. I'm sure it makes more of a difference on more built/powerful engines but for me the advantage of shifting later (past 6500) in the RPM band is effectively minimal to none.

The RPM drop on the 1-2 up-shift is more than 1500 rpm. You have to factor out tire spin.

http://www.bgsoflex.com/cgi-bin/shi...=6500.&hp8=270.&rpm8=7000.&hp9=220.&rpm9=7500.

 

[OzzDOA]

Well here is what I got when I plugged into that calculator:

Click Here

Even though it says the 1-2 shift drop is more than what I came up with but it does support my over-all conclusion.

 

[Ben99GT]

You don't have sufficient RPM range entered in to properly calculate shift points.

"Using the Criterion for Maintaining the Same Horsepower Before and After Shift" is the one you need to pay attention to, it parallels the best real world results.

 

[Ben99GT]

http://www.bgsoflex.com/cgi-bin/shi...=6500.&hp8=230.&rpm8=7000.&hp9=190.&rpm9=7200.

 

[OzzDOA]

With a wider range (I don't have data past 6700 RPMs so I had to estimate the last two values and the results seem rather scewed) :

Linky

Very interesting results when compared against my little "practicle" experiment. But that calculator deals in pure numbers and doesn't really factor in clutch slip, driveline friction, rotational inertia provided by the flywheel etc. etc. It is assuming a 100% efficient system.

 

[98 N/A 4V]

Forget peak hp you need to shift at peak torque. Thats where all the acceleration is had.


















































:lol:

 

[Ben99GT]

With a wider range (I don't have data past 6700 RPMs so I had to estimate the last two values and the results seem rather scewed) :

Linky

Very interesting results when compared against my little "practicle" experiment. But that calculator deals in pure numbers and doesn't really factor in clutch slip, driveline friction, rotational inertia provided by the flywheel etc. etc. It is assuming a 100% efficient system.

I can tell you right now your car is not making 210 rwhp at 7500 rpm if you have a 306 rwhp basic bolt-on N/A car. See the last link I provided, those numbers should be relatively close.

And you can realistically knock a couple hundred rpm off of the 1-2 shift, but otherwise that calculator is fairly accurate.

 

[OzzDOA]

I know, like I said it was an "educated guess" on my part. I assumed a smoothe curve from the last data point I had and went with that.

FWIW I did the math on my own that that calculator does for you and the results of my experiment are fairly accurate for a little "quick and dirty" trial. The variance in calculated rpm numbers and my observed results is only 200 rpm or so. A margin of error of only 5%, which I would say is rather acceptable and can be easily explained by differences in shift times etc. I will give you the point that to maximize the HP after any given shift I would need to wind out the engine more than I do, but based on my observed and calculated results the difference between what is optimal and what I practice is minimal at a few percentage points.

I will say I have enjoyed at least this portion of this thread, the damper debate on the other hand had caused me quite a fair amount of aggrivation.

 

[Ben99GT]

So fellas, how about a discussion on throttle bodies or 3.73 gears?

How about shift points? :rockon:

 

[tmhutch]

To be honest I got a 9 hp and 11 trq increase at the wheels from the Steeda pulleys, did a baseline run before and after the install. Being an engineer by trade I took a really good look at the Steeda damper before install. To be honest I was concerned about them and wanted to be 100% sure I was comfortable with installing the part. Externally it appears to be constructed in the same manner as the stock Ford damper. An inner pulley component, layered with a rubber harmonic damping ring (which is 50% thicker than the stock piece, I measured) and finally an outer ring which provides the vast majority of the rotational mass and inertia. While I have no idea of the actual manufacturing process or tollerances it appears to my eyes to be an adequately engineered product which uses the design of the stock part as a basis for improvement. Now I have my engineering/physics education, several weeks of searching the forums and reading on this exact subject and the opinions of tuners and builders that I trust which contributed to my decision. What do you have? 8 years of reading the interwebs?

To recap:

To be honest I got a 9 hp and 11 trq increase at the wheels from the Steeda pulleys, did a baseline run before and after the install.

LOL, are you sure steeda isn’t paying you. That's not a typical result for under drives (not counting the fluid filled units) but it still illustrates my point that the damper itself is not worth much since much of the gains can be achieved from simply putting the larger pulleys on the accessories. No need for the small damper. If a person really wants to squeeze every last hp out of it, run an electric water pump in addition to the pulleys. The reality remains, small damper = very little benefit.

Being an engineer by trade I took a really good look at the Steeda damper before install. While I have no idea of the actual manufacturing process or tollerances it appears to my eyes to be an adequately engineered product which uses the design of the stock part as a basis for improvement.

That is good. You took more precaution than 99% of people. It was the right thing to do but unfortunately observing it wont tell you if it properly controls harmonics. That requires a very specific test that Steeda could make public if they actually conducted it. Looking at the damper also doesnt address steeda's history of issues with run out, or more simply put, being out of round. That would require an actual measurement with a dial caliper. That's simple enough. Maybe you got a good one, maybe you didnt. You wont know if you dont measure it.

In the end, you're still paying steeda $200 to field test their product for them. Which is fine because it's your choice. Nobody is trying to say you are not allowed to take that risk. The only thing I have a problem with is someone perpetuating an ongoing marketing campaign for a product they can only guess is safe because it looked OK.

Now I have my engineering/physics education, several weeks of searching the forums and reading on this exact subject and the opinions of tuners and builders that I trust which contributed to my decision. What do you have? 8 years of reading the interwebs?

LOL, in addition to an education I have common sense. You almost made it through an entire post without putting your foot in your mouth. I was really pulling for ya too. Keep trying.