etherhuffer

March 2002 Motor Trend- the new Ford GT-40 was to have a "5.4L supercharged and intercooled v-8" Also, heated air is less dense than cool air. That is why you lose the pump rate. Sterling, whatever sort of monster you create, I want one just like it!

Sterling

mar3
"Yes, but the reason you don't hit a peak psi and hold it as revs climbs goes back to the efficiencies...even at 80%, you're letting 20% air escape compression at max psi when sealing is optimal because of sheer rotor speed...at lower rotor speeds your losing more... "

====How come the graph illustrated on the Eaton site demonstrates a straight line?
I'm not disputing that Roots blowers have inefficiencies; I'm just contesting the amount of inefficiency you seem to think they all have.
You also seem to believe that the useable output band on a Roots blower is very very small before it drops off dramatically towards sheer uselessness.

"Damn your eyes!! Now I'll have to get 150 HP jets of NNNAAAAAAWWWSSSSSSSS for my streetport!! Course, it might help if I just got it running again.... "

Yeah. Why don't you start by giving it a friggin bath! I've seen the pics!


etherhuffer

"Also, heated air is less dense than cool air. That is why you lose the pump rate. "

Said that. Just took me about fifty times as many words.

"Sterling, whatever sort of monster you create, I want one just like it! "

I'm taking detailed photos and notes on everything I do. Every part I make will be drawn in detail accompanied by notes.
I'll be machining all my parts with what I call the "What if?" in mind - That is, I'll be planning out the parts thinking, "What if this does'nt fit/work/needs to be changed?".
In this mannor, I'll be leaving alot of extra meat on pieces (aluminum) just in case I gotta make changes.

When all is finally working perfectly, I will draw up blueprints with that "extra meat" removed, and a list of necessary parts.
I won't know if I'll want to make and sell "Eaton M-62 TO 12A" engine manifolds until I make one.
But the whole idea is to use junkyard Eaton blowers, do some fab work, use any carb you want (I'll design an "all-carb" size box), and go from a stock 12A rex to a virtually bulletproof 225 HP machine for LESS THAN $1000!!!

Shell out another grand for a rebuild kit and port the bastard. Who the hell knows what the HP #s would be like on a home made ten psi bridgey 12A?!

Look, I paid $400 for my rebuilt Eaton blower.
I have to make the plenum, the carb box, the idler arm and pulleys, and carb linkages. I will use an OEM junk yard IC from a stout car...what? 25 bucks? fifty? A little elbow grease and creativity, and it'll all look like something flashy I bought fer a ****** Civic!

I still believe that anyone can do this. You just have to use yer noggin, ask lots of questions, and use yer imagination.
Don't be afraid to experiment.
(Just don't be lookin at my ***!)
But seriously...There's nothing wrong with adapting junkyard parts to our needs. When I look at the prices of "ready to bolt on" blower packages, the ole junkyard gets even more inviting!

...Plus you get to brag that you did the whole thing yerself.
(They don't have to know that everybody on the forum helped!)

etherhuffer

Sterling, you're a hot rodder at heart, you just don't know it! this is a way fun idea. I agree, why pay 3K for an Atkins if you can fab it. Question, where are all the Eaton blowers laying around? Are these off bigger equipment, trucks and so forth? I am interested in the machining as a friend has a mill and lathe. Another question, how do you think this compares to the 12A turbo j spec that you see over at the Hitman site?

kf4yas

Where can you find the blowers from GM, Ford, and others? I have a flyer here from a place that deals in rebuilt ones.

Turbo Air, Inc.
5249 ZMAX Blvd
Harrisburg, NC 28075

(800) 438-1060
Fax (704) 454-5018

Ask them for a flyer. They seem to deal with dealerships and repair shops more than individuals. They also deal with blowers for tractors, semis, excavators, and boats.

As for the pop-off valve on a blower, the old 6-71 and other GMC blowers (they came on the old GMC trucks and later everybody copied them) they have a valve on the rear to protect the engine in case of a problem.

The reason that ProCharger had such a higher claim in HP increases is that they offered an intercooler kit. Now that Paxton and VorTech offer them, they are all about equal.

Since a rotary engine is really an air pump, I think it would be cool to build a 13b with a mini rotary (motorcycle, or other) as the blower. Rotaries helping rotaries and if it blew a seal, you could rebuild it with knowledge you already have.

And from personal experience, people have a look of shock when they see a naked 13b with a blower hanging on the side topped by a holley.

Now if I could only figure out the ignition problems, I might get to enjoy my ride.

V8kilr

personally i have never seen a carbed engine supercharged in a blow-trough configuration,

i have seen a blower with the carb mounted on top of the blower but not a belt driven super blowing through the carb,

i know a guy on ebay that sells the mounting kits to mount up a common paxton and vortech super to a 13b,
but thats fuel injection

and regardless of what anyone says all superchargers do not push equal psi throughout the rpm band,
they have to build up presssure just like a turbo,they just do it faster.


here is an aritcle i have learned alot from and the people at scc archived it,
i actually have the magazine this article is in and am suprised i found it on the net,

this is the article that tells how the rotary was first conceived as a supercharger,and it concentrates on the pro/cons of a centrifugal super

Supercharger Overview

Sterling

etherhuffer

"Sterling, you're a hot rodder at heart, you just don't know it! this is a way fun idea."

====I'm 33. I just know that in 20 years, when I'm wiser and fifty, I'm gonna have something damn cool in my garage that will always be "Almost finished!"

"I agree, why pay 3K for an Atkins if you can fab it. Question, where are all the Eaton blowers laying around? Are these off bigger equipment, trucks and so forth? I am interested in the machining as a friend has a mill and lathe."

====Atkins' Camden blower is a damn rip-off. Now I dunno 'bout Atkins' other products or business habits (I.E., If they are ripper-offers in general), but the Camden kit is a TERRIBLE deal! I say that with the uttmost confidence never even having seen one!...And here's why I say so:
For 2300 smackers, you get a VERY old-school blower. It's a two lobe, straight lobe, suck through design. It's terribly unversatile in that it can only be used in this mannor. The installer also needs to tap into the engines circulating oil supply to keep the unit from blowing bearing guts. There are no by-pass or POVs to my knowledge. The two lobe design lends itself to pulsation (in any roots), and consequently will have a harmonic vibratory effect regarding ideal intake efficiency (it will be minutely inconsistant).
I've heard that there are problems with the gear shims, which means timing issues with the blowers. (You only need a "timing issue" for a very short time to wreck a blower.)
I've talked via these sites to a handful of people that have/had one. All...ALL were very satisfied with the end result, and the performance that the blower gave.
It's hard to bring yourself to say you're unhappy with a $2300 purchase, I do realize, But I believe that these people really were happy with the product.
MY beef is with the outrageous cost for a piece that is the absolute bare-bones minimum in tech advance in roots style blowers. I would not have an issue with the Camden kit if were appropriately priced at about a grand less. Hell, I almost bought one for 2300!
But for $400, I purchased a rebuilt (by a guy certified to rebuild stuff) Eaton M-62 blower from a Pontiac Bonneville.
This is an OEM part using the lastest technology in air flow design, guaranteed by both the manufacturer (Eaton) and the auto manufacturer that uses it(GM) for ONE HUNDRED THOUSAND MILES!!!!!

People, You Cannot Beat That With A Stick!!!!

Know where I got the damn thing?...
EBAY.
Now if it cost me $450 for the blower plus shipping, lunch and beer, That leaves $550 for any other components you need, like an intercooler, POV, hoses, sheet aluminum for the carb box, what ever. Now you're up to $1000.
Now I know I don't have to tell etherhuffer this, but everyone else...Get **** from the yard. Not like all them moving parts in an IC are gonna wear out! Plus, an IC from a beefy production car, like a Starion (what I've read here) will be more than adequate, and much less expensive than some shiney new thing.
The hardest part is to get the manifold, idler arm, pulleys and some linkages made. (the alternator has to be relocated to where the AC was). For some that's a ridiculously difficult challenge, I do realize, as not everyone has a milling machine kicking 'round their shop.
But draw up blueprints (or just wait for mine), and present it to a machinest. (which I have not done yet.)
I'd be shocked to hell if it's anywhere's near the remaining $1300!
Even if it is, then you've spent 2300 on a system that FAR SURPASSES anything you could expect from the Camden.
If you can fab everything yourself, you can do this for less than a grand. I'm sure of it.
"Bolt on" kits are for little rich kids, kids that work too hard to get one, kids that think the sticker that came with the kit really adds 5 HP, the mechanically challenged (I know you can't help it...just don't put the damn sticker on your car!)and sissys!

"Another question, how do you think this compares to the 12A turbo j spec that you see over at the Hitman site? "

====I have'nt been paying attention. What is the Hitman site?


kf4yas

"Where can you find the blowers from GM, Ford, and others? I have a flyer here from a place that deals in rebuilt ones.

Turbo Air, Inc.
5249 ZMAX Blvd
Harrisburg, NC 28075

(800) 438-1060
Fax (704) 454-5018

Ask them for a flyer. They seem to deal with dealerships and repair shops more than individuals. They also deal with blowers for tractors, semis, excavators, and boats.

=====There's all kinds of blowers on Ebay. This whole project, as well as my approach, is designed to appeal to the enthusiasts with thin wallets (I think that's most of us.)
You're unlikely to get any warrantees with anything from Ebay, but there are rebuilts and new ones to be had. You take a chance...no denying that. But you can shop smart.


As for the pop-off valve on a blower, the old 6-71 and other GMC blowers (they came on the old GMC trucks and later everybody copied them) they have a valve on the rear to protect the engine in case of a problem.

The reason that ProCharger had such a higher claim in HP increases is that they offered an intercooler kit. Now that Paxton and VorTech offer them, they are all about equal.

====I read of an instance where the addition of an IC lowered the manifold temp 70* !!! I have no idea if this is typical, but it spells power to me!

Since a rotary engine is really an air pump, I think it would be cool to build a 13b with a mini rotary (motorcycle, or other) as the blower. Rotaries helping rotaries and if it blew a seal, you could rebuild it with knowledge you already have.

====I like the way you think!!!

And from personal experience, people have a look of shock when they see a naked 13b with a blower hanging on the side topped by a holley.

====What brand blower?

Now if I could only figure out the ignition problems, I might get to enjoy my ride.

====You will.

Sterling

V8kilr

"i know a guy on ebay that sells the mounting kits to mount up a common paxton and vortech super to a 13b,
but thats fuel injection

and regardless of what anyone says all superchargers do not push equal psi throughout the rpm band,
they have to build up presssure just like a turbo,they just do it faster.


here is an aritcle i have learned alot from and the people at scc archived it,
i actually have the magazine this article is in and am suprised i found it on the net,

this is the article that tells how the rotary was first conceived as a supercharger,and it concentrates on the pro/cons of a centrifugal super "

=====V8kilr-

I have not looked at your link yet, but I will. I do think I have read it before, but I'll see. The last thing I want to do is be someone who does'nt try to learn all he can, yet opt to dish out opinionated advice to others (as I have been accussed of such.)

However...I do believe (now I could be wrong particularly about the Paxton, I don't know) that the two blowers you mentioned that your friend makes brackets for...The Paxton and the Vortech; Are centrifugal blowers.

At the very least, the SSC Mag. artical you have a link to, you say "...concentrates on the pro/cons of a centrifugal super...".

The Eaton models M-45, M-62, M90, M-115 are all Roots blowers...That is, "Positive Displacement" blowers.

These are VERY VERY different than a centrifugal blower.

==============================================
Just read the artical. I'm very impressed, as usually I find SCC articals to be either biased, or missing some important facts and so not illustrating 100% off the pros and cons of the subject. (I.E., I usually am disappointed at their journalism.)

Anyway, I thought the artical was great. Did you get bored with it, and not read the whole thing? It clearly goes on to illustrate most all of the popular blowers, all of which are positive displacement types save one.
Granted that one type (the centrifugal) may be made by more companies, they are all basically the same.

Though the artical was too short to go far in depth on every type of supercharger it illustrated, it certainly does say enough to make the bottom portion of your statement, "...and regardless of what anyone says all superchargers do not push equal psi throughout the rpm band,
they have to build up presssure just like a turbo,they just do it faster. "
...false.

I'm not trying to pick on you! It's just that you walked into a conversation and showed yourself to be a perfect example of alot of intelligent car guys that tend to lump all superchargers together and seem to think they all behave the same way.
Some think, "positive displacement...constant boost available right off idle", whenever they hear 'Supercharger', discounting centrifugal SCs.
Others think "Built-up boost just like a turbo, only without the lag...", of course discounting all of the PD type blowers.

This is why I hate those "Turbo vs Super" arguements...Everybody goes in adding their two cents with what their idea of a "supercharger" is.

Centrifugal superchargers should either be catagorized along with turbos, or all by themselves. Centrifugal blowers are the same thing as turbos. As the RPMs double, the volume they pump is squared!. They are the only forced induction devices that behave this way.

But the artical you presented to us demonstrates that there seem to be many more flavors of supercharger than most know.

mar3

iTrader: (8)

I'm a big fan of SC's, don't get me wrong, sterling, I just think that in some applications, that's really not the way to go. In your case, with the $$$ being on the low side, it's damn hard to argue against it. Regarding boost and efficiencies...I'm not saying SC's are pathetically inefficient, it's just the leak down rates are part of why you don't build instantaneous full boost just off idle. Another though-o-gram-------> When I ran the dyno, I made 113 HP at the wheels...how much HP do I make at 2000 rpm? at 3500 rpm? at 5500 rpm? The answer is not 113 HP and the answer will also be you won't get 8 psi boost at 4000 rpm if your pulley is sized to spin your compressor for 8 psi max at engine rpm speed of 6500...it will build in a linear fashion from some number, let's say 2 psi arbitrarily, at just off idle to its max of 8psi at 6500 rpm...with the pulley selection, you determine where max boost will come in for your application, that's where the formula comes in handy that I sent you via PM earlier in the year...

Wankel Bug

Couple of items.One-I've seen quite a few cars with
turbos and superchargers using carbs.Mostly in HOT
ROD magazine on V-8's.Everyone who does this has some kind of box around the carb.Of course they used sealed fittings for gas lines and linkage.
Two -there is a intercooler designed and used on the big 6-71 style roots supercharger.Its like a sandwich
and fits between the supercharger and the engine.Uses
water to cool .Works so well NHRA banned it for drag
racing.

etherhuffer

Go to Eaton's page and they have graphs of output vs rpm etc. Worth a look. What is on the Millenia S Miller Cycle?

Sterling

Originally posted by mar3
I'm a big fan of SC's, don't get me wrong, sterling, I just think that in some applications, that's really not the way to go.
===Funny...I pegged you as one who would'nt be able to come up with an ideal application for a supercharger.
...Ever.

Regarding boost and efficiencies...I'm not saying SC's are pathetically inefficient-(yes you are)-, it's just the leak down rates are part of why you don't build instantaneous full boost just off idle. Another though-o-gram-------> When I ran the dyno, I made 113 HP at the wheels...how much HP do I make at 2000 rpm? at 3500 rpm? at 5500 rpm? The answer is not 113 HP and the answer will also be you won't get 8 psi boost at 4000 rpm if your pulley is sized to spin your compressor for 8 psi max at engine rpm speed of 6500...it will build in a linear fashion from some number, let's say 2 psi arbitrarily, at just off idle to its max of 8psi at 6500 rpm...with the pulley selection, you determine where max boost will come in for your application, that's where the formula comes in handy that I sent you via PM earlier in the year...

First of all, I just have to say this:
I don't give a **** if a turbo is better for my given application.

Secondly, you keep talking about positive displacement blowers as if they are all centrifugal blowers...that is, only producing boost when they get to a certain speed, and producing more boost as speed increases.

Positive displacement blowers ...As Is My Understanding...
Don't behave that way!
They are designed to pump a specific volume of air per revolution that does not change with speed. There are in fact changes, but they are due to heat and leaking between the rotors.
But the leaking is not as terrible as you make it seem, and is easily overcome by just a slight more overdrive. The heat issue is combated with intercooling.

It's that simple. You set it up for 8psi...It makes 8 psi @ 2K RPM and it makes 8 psi @ 6K RPM.
Any changes in boost are slight.