agreed! But in those situations, I know for my $125 I'm getting SHINY! : )Quote:
Originally Posted by bandook
and i I almost paid +200 for a spoiler I didn't need, but wanted...
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agreed! But in those situations, I know for my $125 I'm getting SHINY! : )Quote:
Originally Posted by bandook
and i I almost paid +200 for a spoiler I didn't need, but wanted...
OK, coolone, this info could actually benefit the thread. Instead of just nay-sayin, post links to this info. I've never seen it and would like to learn more.Quote:
There also information about he rotors being unbalanced afterwards, warping and more.
Andnthanks for the lesson in parasitic loss, but I never said less weight CREATES HP. I said it allows more usable power. Dunno why you spun it that way?
Smh
I've got to side with cool one on this. Rotating mass takes energy to accelerate - but not to maintain at speed. So lightweight parts (like flywheels etc.) will take less power to get up to speed, but that's not where the significant HP "draw" comes from on a supercharger, it comes from propelling & compressing the air. Now if you simultaneously change the geometry of the rotor (i.e. deeper root etc.) to create more boost, that will suck more HP (but you will gain HP from the increased airflow). The lower rotational inertia of any rotor mod's will be pretty insignificant.
If you want to Google "rotational moment of inertia", you might learn some interesting things. It's why taking 10# off your wheels will give you more acceleration benefit than taking 10# off of a non-rotating part (like removing a seat or something). Because not only do you have to get the wheel moving to 100MPH by the end of the 1/4 mile, you also have to get the mass of the wheel spinning to XXX RPM.
-Bob C.
And I personally find it ridiculous but I don't go around second guessing everyone's decisions to do so. Unless it actually hurt there performance and I had proof of it. Very interested in this proof you have of warped rotors etc from modding them. Seriously.Quote:
Originally Posted by coolone
The rotors can be rebalanced, like balancing a tie on a wheel. As far as less inertia goes, that is negated by running a smaller pulley, I read about a guy in Australia running a 2.2" pulley.
It seems the debate is going to continue because steigemeier isn't offering the service.
He doesn't have that information because he doesn't even know what was done, in the thread it mentions re-balancing after they are are drilled, that I believe should be common sense. It was several years later when I learned how to balance rotors.
It requires 60 HP on a Supercoupe early model supercharger to make 13psi. This has been proven before we had supercharger dyno information, and information from Eaton on the subject.
lightening the rotors was actually done on several occasions with success and failure. Not long after the thread I linked was done I did a lot of work on superchargers. I disassembled them all the way down to the bearings in the cartridge plate, I learned how to time them, because it's not as easy as you think. I weighed the rotors and all of the rotating components and had information on all of that.
Unfortunately when The SCCOA and the TBSCEC merged the information on the TBSCEC was transferred into the paying section of the SCCOA to keep out all the guys that just wanted to come and hang out and was dedicated to the technical side of SC's there is a wealth of information in there. Most of the guys there were fed up with the parrots and that's how the TBSCEC was formed. I cannot tell you how many of the guys were/are engineers with different backgrounds and the exchange of ideas is a lot of the reason why there are so many much faster SC's running M90's than there are GP's running M90's.
Another thing I see here is the piss poor porting jobs. I see ported supercahrger and look at what was done (or not done) and see a bunch of superchargers where people run a sanding roll across the inside surface of the blower housing and they call that "porting", hell that's not even polishing.
There are too many bolt on boys here that think because they bolt on a set of headers, an intake and pulley they think they know all there is to know about this platform and they are an expert. The fact is there is about maybe a handful of people on this site that know their stuff when it comes to these cars, then there are a ton of guys that barely know which end of the wrench to hold.
Then there's a guy talking about "rotational moment of inertia", but doesn't even know how much a rotor by itself weighs, how much material could be removed and it's weight, yet he's talking about light weight flywheels.
Where's that Jackie Chan frustration meme.
Jeff
it was one of my plans back in the day to do a heads, cam, non-intercooled, high boost setup with an overdrive balancer and as tiny as a pulley as i could get on the car with stock timing tables. it would be very cost effective and it'd probably move like nobodies business. toss some E85 at that kind of setup and you're going to run out of pulleys to use.
honestly, i think you're putting too much thought into this and you should try to dumb it down some more.
Nick,
I don't mean any disrespect with this, but I have been messing with the M90 since before you were out of high school, so I know a thing or two about making that pump move some air. I worked on it so long ago that I actually was able to talk to guys at Eaton and discussed at length about how to make more power with it. As you probably know the OEM of anything makes compromises to keep things in check, I was able to talk about the testing they did and what would make gains and what wouldn't. I was the guy that was told where to remove material and where not to, I was also told about the new upcoming Gen V blower and all about the abraidable coating about 5 years before the thing even came out. We even discussed lightening the rotors which they had also tried, in R&D and found to be effective, but was shot down by the bean counters. They even had carbon rotors that were super light weight and said upped the effeciency by almost 10% but cost at the time was more than 15 times the price of aluminum rotors. I also have a father in law that is a chemical engineer that has a solid foundation in fluid dynamics and was able to play with the FEA program and see how different porting methods made a huge impact. Some of which would drop your efficiency and flow through the floor like porting the middle area between the rotors.
As far as dumbing it down, that's the attitude that I fight against all the time. Everyone is so freaking lazy, they don't want to search, they don't want to learn they just want it handed to them on a platter.
When I first came here, I didn't see any meaningful dialogue about how can we make this platform faster. All I saw was a bunch of whiny kids that think their stuff don't stink and very little technical discussion. I have read just about any and every sticky and to be honest there isn't a lot here. I saw a few guys trying to help and a lot of guys just screwing around. I asked detailed questions giving the maximum amount of information so I could get help and all I got was a bunch of guys that couldn't troubleshoot their way out of a paper bag argue with me about stupid things. In fact, I believe it was you that said I was arguing with people that were "trying to help" unfortunately a couple were and the rest were just making trouble, I would expect more from a mod. It wasn't until Bill came in and shut that business down that I got someone to actually help troubleshoot and solve my problem.
I do not want to dumb it down and think it would be a disservice all the people that WANT to learn, and another way to keep the W-body platform down. Yes the transmission is weak we all know, but that shouldn't deter us from seeking more power should it?
Jeff
i was coming into this discussion with the assumption that it wasn't an all out, max effort build for record breaking horsepower. my thin wallet usually doesn't allow those types of situations because i'm not made of money, nor am i a machinist that can make/modify my own parts.
i'm all for going all out with this and seeing where it goes, but when you start talking about diminishing gains you really have to weigh out what is really important.
I was under the assumption after talking to Tom @ AnimuL back in the day that he had gone through the bench testing and said anything north of a 2.8" on a GenV, or 2.55" on a GenIII wouldn't be worth the gains, since it was taking so much more power away to drive it. People had gone about re-coating and re-timing the rotors, and even gone as far as drilling out the lobes, so make them lighter. I still think there is plenty of cool things that can be done, buttttt...
Inefficiency comes to mind to a certain degree.
Then again, I wanted a W140AX setup.
Sure, I can understand that, but in seeing Sgt's threads, he has been asking questions on making more HP, and at this point in his build I wouldn't even consider drilling rotors, there is too much porting and other work to do, that just tells me he is thinking ahead. This is something everyone should do in search of more power, we as a group shouldn't poopoo an idea, especially when we don't know for sure. You will not see me in a thread on tuning telling someone what to do or not to do, because I haven't made it that far with this platform yet. Matter of fact the last time I messed with a computer and a GM computer I had to take a CRT, keyboard, mouse and tower out to the garage to get close enough to make changes. and I only had about 5 options to choose from. Now the EEC-IV I had EEC tuner and that's a different story.
Jeff
i overbuild everything i make so we're on the same page mentally. i just don't like to push people's wallets when i'm not seeing that it'd make a fabulous seat of the pants 25whp difference at the end of the day.
I would just continue to save for a turbo kit
at this point, I plan on doing a 130 lb valve spring setup with a double roller and an over sized harmonic balancer. when I take the valve cover off I'm going to take some measurements to check for clearance so I may be able to do a 1.7 roller rocker. I'm not optimistic the valve guides have been milled for the additional clearance.
seeing as how steigemeier doesn't do the rotor drilling anymore, I'll probably at a methanol injection instead.
It makes since though I like the concept and would help alot as far as parasitic loss
There was a guy here from Austrailia that re-coated and drilled out the rotors.
Was like $500~ to do it though lol
my rotors have the gen 5 coating, so I would rather not get them recoated. I'll have to decide if I want to pay shipping from australia.
It ain't easy for sure, you have to time everything the gears, front of the shafts and gear. Just making a permanent mark in them on purpose where you want them is hard, I literally flattened a brand new center punch on the gear. Then after you have everything marked so you can put it back together you have to use about 20 tons of force IIRC (I was on a 50 ton press) to get them out which means supporting the rotor plate very well. Then doing the same for the other. Then you have to set it up in a machine and make a jig to hold it just right, which is pretty complicated in itself (don't want to mar the rotors surface). Then you have to have long drills (not hard to get) and be careful not to wander, then step it up to just before the final size. Then using a long endmill (finishing) bore the rest out and get a nice clean finished hole. After that you need to balance them. Balancing is not too bad, either get with a drive shaft balancer and ask what kind of precision they are capable of and they should be able to do +/- .5 gram or better. I actually designed a balancer using our scale electronics, an encoder, loadcell a PLC and mounting blocks with bearings and a chuck on one end and a motor to drive it for a different project, maybe I'll bring it back up. I have the code somewhere. Then there is pressing it back together. the first one is easy just start pressing the gear on and when you get close you can rotate the shaft to the final position. if you end up one knurl off you have to reset it. The second is a little more complicated as you have to have the gear in place and slide the rotor in then set everything up to press on the rear of the rotors (goes the same as the first) now since you have a 60* helix it gets a little tricky as you have to line the second one up and then press it while allowing the one that is already in rotate. You have to measure how much it is going to turn and offset it by about half then start pressing and checking then you finally get it in place make sure nothing rubs and it is as smooth as before.
Changing bearings is going to have to be another post.
I don't think I'll do it myself