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oversized harmonic balancer

SgtMarshal

SgtMarshal

Active member
I'm thinking about changing my harmonic balancer to an oversized one and am curious what pulley on the supercharger will be equivalent, like is it comparable to 1 pulley size drop? if my idea to run a lightweight rotor pack, I will be able to run a pretty small pulley, probably smaller than a 2.6. I want to scare people with my car on halloween. that supercharger whine is going to be astounding.
 


well, maybe because no one has done it yet, and you aren't in the cool kids club like I am. I haven't actually received confirmation that they can do it yet, last I heard was that the guy who did the rotor lightening had quit doing it, but was going to start back up in the near future. I plan on following up with them again next week.

http://stiegemeier.com/services/lightweight-rotors/
 
Yeah, I was kicked out of the cool kids club when I supercharged an 01 Impala :( That's pretty frigging cool. I kinda already lightened my first set of rotors when I stripped all the coating unintentionally though.

Which oversized HB are you looking at? The zzp one is 5% and they say its like decreasing sc pulley by .1-.15".
 


Lightweight rotor packs do nothing, but relieve you of $... Might as well get a snout cooler too while you're at it. There are no hidden jewels awaiting to be discovered in an engine that had its run over two decades. The HP trials are over. If you want HP, it's there, and the road maps are in their 12th printing... just sayin... You'd be better spending that money towards stageIII or better heads or something that will give you proven results!

Unless of course you just want them to be able to say you do (have them)!
:D
 
coolone said:
Lightweight rotor packs do nothing, but relieve you of $... Might as well get a snout cooler too while you're at it. There are no hidden jewels awaiting to be discovered in an engine that had its run over two decades. The HP trials are over. If you want HP, it's there, and the road maps are in their 12th printing... just sayin... You'd be better spending that money towards stageIII or better heads or something that will give you proven results!

Unless of course you just want them to be able to say you do (have them)!
:D
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I would have to disagree with you since the Tbird SC is heavier (4200) and there are much faster Supercoupes out there than GP's I watched you guys from afar while I had my SC and at the time a 13 second SC was a pretty fast car. There are guys in the 10's on what you guys would call a Gen 3 blower. Granted it's been worked like no ones business but it's still a Gen 3. We had one guy with a modified blower with a home port job that picked up 70 Hp with a Magnum Powers blower matching inlet plenum and 85mm TB alone, with dyno sheets to prove it.

That car ended production in 94' and they are still coming up with stuff to go faster. Back when I got started you couldn't even buy a cam you had to send it in and have it reground, and we were damn glad to have it! Hell I checked in not to long ago and was surprised how many people are in the 11's now. There is a whole lot of nay-saying on this board and that's why the GP isn't where it should be. I even recall back in the day there was a shootout covered by MM&FF and there was also a SC vs GP shootout as well, do you remember those?

The biggest problem I have with what you said is that there is nothing else to do, BS there is always something else, you just haven't found it. It's like every time someone says something a bunch of people jump in and say No even though it hasn't been tried. I see a lot of parrots on the board and that isn't the way to be. Think outside the box.

By the way do you know what the weight of a rotor is? I do because I have taken them apart to that level and reassembled them. If you haven't done it then you don't know and if you haven't done it then at least be open to a discussion instead of "It's all been done before" or that won't work. Because it hasn't. It's amazing how the SC crowd has come up in HP but the GP crowd has just kinda fizzled into "Here do these bolt on's and that's all you can do."

I came on here and heard all this business about not being able to rebuild the bottom end and thought to myself that has to be one of the dumbest things I have ever heard. It can be done, if you know how to actually rebuild an engine and not take things apart put some new gaskets and bearings in it and call it a "rebuild".

Come on now lets make these things faster. Everyone should have a 13 second flat GP here by now. You guys are struggling to get into the 13's with an engine that already makes more than 1 hp/cu.in. I would think by now that there would be a list 2 pages deep of high 12 second cars.

Let the Sarge speak, as there was a hole (pun intended) discussion on drilled rotors over on the SC forum about 10 years ago, maybe longer.

Jeff
 
Cool one has been know to just jump in threads and piss in your cheerios. I think he's burnt out on the platform and feels everyone else should be too. I see a lot of his posts are just negative Nancy talk, for some reason trying to squash contemplative discussion. Perhaps he's a blue oval mole?

But anyways, the physics are there. You make the rotor pack lighter, it will take less to drive it resulting in more power to the ground. I've heard that the blower steals about 60 HP just spinning it. Basic physics says if you lower its mass it will take less crank HP to spin, which results in more usable HP. Right or wrong? Same reason people install other parts with less rotational mass, like flywheels and driveshafts.
 
the other benefit to light weight rotors is that because of reduced weight there will be less heat generated. I have a 2.6" pulley that I intend on installing after the rotor lightening and will be curious how much more boost will be produced.

Right now my plan is to do a weight reduction on the car by taking the rear seat and a lot of other stuff out that isn't really necessary and make it a drag car. my one requirement is that I want to be able to drive it to the drag strip. to do so I plan on dropping the gas tank out and installing 2 fuel cells. one fuel cell for regular gas and the other for high octane. I know I probably won't be saving weight by installing two tanks but the convenience of being able to switch back and forth is pretty substantial. I may even run some methanol. I'm curious how close to a 12 sec 1/4 without nitrous. at some point I'll probably take the front seats out and replace them with lightweight racing seats.
 


Too long didn't read. At least that's what the kids say or something like that. Maybe a colon at the end or something.
 
TL;DR

i would personally not really want to pay for the lightened rotor pack for the unknown/minimal gains you may or may not see, but that's just me being a fiscally responsible adult.

have you thought of doing the overdrive balancer along with the rest of the setup (heads and cam?) and think about dropping a little meth or spray on top.
 
methanol, spray, and the overdrive balancer are all in the works. I just need to start working again to fund all the projects, and my new job starts on September 1. I'd like to have some good consistent before and after track runs to see what the benefits are of the light weight rotors.
 
hey man, if you feel like paying for it more power to you. i just wouldn't want to take that leap myself. i know there are more efficient ways to make power. like ditching the blower and going with a turbo, heh.
 


Removing the balance shaft removes rotating mass too. My new motor will not have one ;) But I will also have ported \ reworked heads and a cam.
 
At this point I wouldn't buy those supercharger parts new. Look for used. Can't find them used, usually means no one bought them in the first place. Not saying it's a waste of time but possibly of a waste of money.
 
bandook said:
Cool one has been know to just jump in threads and piss in your cheerios. I think he's burnt out on the platform and feels everyone else should be too. I see a lot of his posts are just negative Nancy talk, for some reason trying to squash contemplative discussion. Perhaps he's a blue oval mole?
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Cetainly a misrepresentation of my character! I don't piss on anyone's cherios, I love the things, why would I do that? I love the 3800 platform and GP's is why I have 3 of them. That said, trying to impart practical no nonsense suggestions to pend your $ while modding on proven things that will effect the desired results you're looking for is certainly not negative nancy talk. Your response reminds me of a child who drops to the floor kicking and screaming when they don't get what they want or are told something they can't respind to. I didn't attack anyone personally, I respinded to the attempt at wasting $$$.

But anyways, the physics are there. You make the rotor pack lighter, it will take less to drive it resulting in more power to the ground. I've heard that the blower steals about 60 HP just spinning it. Basic physics says if you lower its mass it will take less crank HP to spin, which results in more usable HP. Right or wrong? Same reason people install other parts with less rotational mass, like flywheels and driveshafts.
Click to expand...

You heard it takes 60hp to spin it? Lol, I didn't know my right arm was <60HP because it spins pretty freely when I have it on a bench. :D

Yes, in theory, a lighter rotating mass will cost less energy to move it and thereby supposedly save the necessary power doing so. There's a problem with this train of though. Number one is the lighter rotating mass does not CREATE any more power, but eliminates a parasitic draw of power. Freeing power doesn't make you faster, just makes the engine work less. If this attempt at freeing power by removing a few grams of rotating mass from the rotors was such work around for free HP, it would have taken off like crazy. The fact it never did, tells all. There is information out there about gains, sure... There also information about he rotors being unbalanced afterwards, warping and more. Go ahead, have them drilled out, let us know how it worked out for you. Flywheels lighter because made with a different material that is both lighter and STONGER. The lighter effect was a side benefit. Cranks is same story. You could make these out of even lighter material but they wouldn't stand to the forces being applied to them.

But like I said, and always say, you have to think about what you want, make a plan, research and execute. Not just do this or that, and then expecting a different result than what has already been achieved. The cost for saving a few HP with these items is not as cost effecting as say StageIII heads IMO where the gains are much higher per $ spent. But if you were going all out, trying to eek the last HP out of your build, shave the last 1/10 sec. off your slips, or for the car shows you just wanted to be the only one with that particular rare hard to find, maybe one of a kind things... Go for it.

but facts are facts... The fastest 3800's didn't get there with hollowed out rotor packs, or oversized flywheels... Just sayin!

: )

negative nancy... Lol
 
It looks like it might be 4-6 hundred bucks. How many of the guys here have dropped 200 bones for basically worthless intakes, or 600 for a shiny catback, or 125 for pretty dogbones, and another 100 for aluminum angle braces etc etc. Lots of useless parts bought all the time on this site lol.
 
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