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-   -   my n/a supercharging project complete (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/my-n-supercharging-project-complete-289791/)

neptuneRX 04-04-04 11:59 PM


Originally posted by rotarygod
I don't think it would be too hard for him to get that supercharger back out if he needed under it for any reason.

My biggest concern about the way he did everything is the inlet and outlet pipes. He is losing so much efficiency by doing it the way he did with the small pipes and blunt transitions. Now that it is working he needs to go back and refine it alot. He'd get so much more power out of it with the same boost level if these issues were taken care of.

It is still a nice upgrade, especially for the money or lack of it. A little work could make it kick ass!

I think he explained that because the SC is from a Thuderbird he can't use bigger pipes.

Disclaimer ---> IMO, I don't think a intercooler is needed for this setup. He's just looking to put a little kick in his NA, he's not build NA to run as hard as the TIIs. But on the other hand a intercooler might help extend the life of engine and sc.


Originally posted by vectorminds
well, atkins is running 8 - 9 psi on the turbo block without intercooling... and thats with their horribly inneficient roots blower... with a centrifugal, whipple, or twisted roots you should be able to boost at least 7 psi on the n/a block without a problem....

yes adding a intercooler would increase power by bringing down intake temps, but i dont think its nessasary for safety... i have a feeling mazda incorperated it into the factory turbo design more for increased performance rather than solely to prevent detonation

also, the nelson/paxton blower made in the past did not use an intercooler and i dont think there were detontation issues with it (just overspinning the s/c and the bracket breaking :p )

just wondering why you're calling akins blowers horribly inneficient. I'm probably going to end up getting one so if you have some data to back that I'd like to see it. No hostilities... just want to avoid buying something that isn't going to work well.

jacobcartmill 04-05-04 12:33 AM

what is this supercharged NA guy (the guy who started the thread) doing about fuel? is he running stock injectors?

FC3S-NovaStyle 04-05-04 01:00 AM

i bet he's problaly doin the write up right now and getting some pix and more info..

rotarygod 04-05-04 01:27 AM


Originally posted by neptuneRX
I think he explained that because the SC is from a Thuderbird he can't use bigger pipes.

Disclaimer ---> IMO, I don't think a intercooler is needed for this setup. He's just looking to put a little kick in his NA, he's not build NA to run as hard as the TIIs. But on the other hand a intercooler might help extend the life of engine and sc.



just wondering why you're calling akins blowers horribly inneficient. I'm probably going to end up getting one so if you have some data to back that I'd like to see it. No hostilities... just want to avoid buying something that isn't going to work well.

The inlet on the back of the supercharger is an oval. He has a round pipe that has no transition going into it. He can make a custom pipe that has smoother airflow and less losses from turbulence. The outlet of the supercharger is a triangular shape. Again, he just has a small round pipe with no smooth transition. This can definitely be fixed. Airflow through a supercharger is just like airflow through an engine. If there are losses through the supercharger from turbulence, there will be more charge heating and a loss of potential power. By changing these so they flow better, he will pick up power without changing pulleys. The fact that it is from a T-bird has nothing to do with it.

An intercooler isn't needed as long as detonation isn't present. It doesn't mean that there can't be more power made with the use of one. For a small increase and simplicity sake I will agree.

The Camden Supercharger is the least efficient supercharger out there. It uses a 2 lobe straight rotor which is the oldest design out there. Eaton took the roots style blower, added a 3rd lobe to each rotor, and then twisted them. This gives more area to catch air, it heats the air less, and it makes the supercharger quieter. Look up supercharger differences online. There are tons of websites with all you ever wanted to know about supercharger differences. You can also try the book "Supercharged" by Corky Bell.

88 vert 04-05-04 08:28 AM

All this talk about S/C,has me wanting to keep my S/C setup.I have the nelson setup from back in the day,i have had no problems with the bracket although i have had a extra one built from steel just in case.The pulley has been changed to prevent overspinning.The setup is sweet and clean,i have had no problems from my NA drivetrain i have RB exhaust from header to mufflers,K&N air filter,S-AFC,550 inj,cartech RRFPR,walboro fuel pump,and a steetported motor.This is the 2nd motor i have lost from the S/C the first one was just for fun and it detonated bad and blew,but before it did it was hella fun.The second motor lasted about 4,000 miles,it was broke in before it got S/C'ed,and then bolted the S/C on it.It was one hella ride,had power from start to finish.I never got to dyno it,i was just cruising about 65,no boost,no dogging it,just cruising with cruise control on,and it blew a rear apex seal.I have since bought a 3rd gen and just want my vert back so this system is for sale if anyone is interested.Im not trying to jack this thread,but since theres so much interest id figure id throw it out there for anyone wanting a cleaner install and bolt on.
But yes im glad to see people wanting to S/C intstead of turbo,i thnk theres a lot of potential from the S/C and lots of fun.

Heres a link to some info https://www.rx7club.com/showthread.p...hreadid=240270

wozzoom 04-05-04 10:23 AM

WHOA WHOA WHOA!

I hate to put a damper on this thread but nobody in 8 pages of posts has questioned once if the Thunder Bird supercharger is properlly sized for the 13B.

yeah the $300 SC sounds like a great idea but can we please get some emperical data here? For example: what CFM's is this thing putting out? What is the max impeller speed? How do these numbers match up with the stock turbo?

I'll admit that I have no clue when it comes to boost, but it seems silly to me just to bolt on a SC without having done some actual research on the topic.

Phu5ion 04-05-04 10:43 AM

I have wondered about that but never really got into it. Here is some information from Eaton's website about the M90.

Their website says it will flow over 500 CFM at redline. I did a quick calculation (anybody feel free to check me on this) and a S5 motor at 8000 RPM "should" move about 370 CFM.

For the lazy:
displacement - 1.5 L/rev
SC redline - 14000 RPM
inlet flow - 540 CFM

DragonRx7 04-05-04 10:43 AM

How come nobody's said "Make this a Sticky!!!" ?

Well, Make this a sticky!!! And good work on the SC.I think this will be my next project.

zbrown 04-05-04 11:53 AM

Well guys iam back, Sorry i only have access to the internet during school(it is sad i know, but at least i get to use a T-1 connection) I personally cant believe how many replies and views there have been. I bout shit when i logged on today. For some Questions:

Everybody wants a write up but i cant really do a step-by-step process. Like for the bracket, i held every piece in the engine bay one at a time and tack welded them in place so that i knew i had them just right. Once tack welded i took the bracket out and welded everything. After i had the bracket welded and put in i had my pulley machined.
I wanted to have the pulley before i welded the bolts that hold the s/c down to the bracket base. Once i had the pulley, i set the s/c on the bracket base and lined up the s/c pulley with the engine pulley, with a straightedge. Once i knew everthing was on the same plane and square, I tacked the bolts to the base, removed the s/c and welded the bolts solid with the bracket in the car.

The bracket is the only thing too it. Ill tell you all what , ill take my bracket out and take some really good pics of it and get some dimensions when i do my blow off valve.
The sad thing is i dont have much time, I am in track and have meets constantly to the end of May.

I am using the pulley that was used for the smog pump. Some of you are worried that the one A belt isnt enough and that was one of my concerns. I wanted to just change the rest of the car to serpentine, but there were no kits mad for it. I think that this is because the water pump would have to turn counter clockwise or the opposite of what it does now because the water pump pulley runs on the back of the serpentine belt, In most cases i think anyways. Am i right about that.

I took it for a 300mi trip this weekend and didnt have one problem, and get this when i got home i checked the temp of the of the alternator pulley and it was at least twice of what the s/c pulley was. I could hold my had on it.

U guys have me all worried about feul so i am going to get 550cc injectors and a boost porportional fpr. (even though i havnt had any probs with pinging)

any body have these they want to sell i use papal

I looked at the flow charts for the m90 before i bought it and i thought it would have plenty of flow, and it does
at 8000rpm the s/c is running around 11,000rpm, not even near the 14000rpm redline.

I gotta go class is over ill write more latter

vectorminds 04-05-04 02:16 PM

i called it horribly inneficient exactly for the reasons rotarygod pointed out... its the oldest and simplest design out there... also the most inneficient. The eaton with its twisted 3 lobe rotors is much better. Even better than that is the whipple which has specialy designed rotors that achieve internal compression making it a true compressor and not just a blower (again increasing efficiency).

If I were to pick a supercharger, whipple would be first, and then an eaton, id probably only put on a straight roots blower if it was free :P

I wouldnt even consider a centrifugal blower, because you may as well go turbo at that point, as it will have more "lag", and will only reach max boost at redline.

Turblown 04-05-04 03:36 PM


Originally posted by vectorminds
i called it horribly inneficient exactly for the reasons rotarygod pointed out... its the oldest and simplest design out there... also the most inneficient. The eaton with its twisted 3 lobe rotors is much better. Even better than that is the whipple which has specialy designed rotors that achieve internal compression making it a true compressor and not just a blower (again increasing efficiency).

If I were to pick a supercharger, whipple would be first, and then an eaton, id probably only put on a straight roots blower if it was free :P

I wouldnt even consider a centrifugal blower, because you may as well go turbo at that point, as it will have more "lag", and will only reach max boost at redline.


You are missing the point.

N/A owners are broke.
This is cheap power.
Sure its not the best way or most efficient, but then again if everyone had money no one would even consider doing this...

wozzoom 04-05-04 03:57 PM

Does anyone know if you can "clock" an Eaton SC 90 Degrees? Or do you have to have it lay flat?

rotarygod 04-05-04 05:14 PM

I am in agreement with vectorminds. As far as superchargers go, my first choice would be a Whipple (twin screw), then an Eaton, and on down the line. This assumes of course price is no object. vectorminds wasn't talking about how inefficient the Eaton setup here is. He was commenting on how inefficient the Camden (Atkin's) supercharger is.

For the amount of money he spent, it is easily the best bang for the buck. If I had an n/a, I would do it tomorrow.

You can turn an Eaton supercharger any direction you want. It's oiling system is self contained and not dependent on the way the supercharger is mounted.

If you want more potential from this supercharger, check these guys out. A modified M90 can flow enough air for 400+ horsepower. Skim through their site.

http://www.magnumpowers.com/index.html

patman 04-05-04 07:34 PM

why not just use the stock adapters from the tbird? i dont know what the inlet looks like, but the outlet would work just fine. who cares if it says 318 on it?

pat

poor_red_neck 04-05-04 07:47 PM

http://i13.ebayimg.com/03/i/01/94/db/40_1_b.JPG
http://i1.ebayimg.com/03/i/01/96/29/27_1.JPG

Looks like it would work pretty good. Just the fact that it exits at a slight angle...

fg0d 04-05-04 07:49 PM

If someone else understands what he's saying, you do the write up. This guy doesn't have enough time to do a step by step write up. But god damn this sounds great. If all I have to do is bolt on the sc and bam, than I'm going to buy myself a N/A.

Also, can you change the pulley size to increase hp?

poor_red_neck 04-05-04 07:51 PM

Wait....

The INLET is on top?

Never mind then... im a complete moron.

So INLET is on top, OUTLET is on bottom?

rotarygod 04-05-04 08:04 PM

Inlet is from the rear. Outlet is on top.

fg0d 04-05-04 08:07 PM

Where did he mount the s/c? I need a better explaination.

ViperDude152 04-05-04 09:26 PM


Wait....

The INLET is on top?

Never mind then... im a complete moron.

So INLET is on top, OUTLET is on bottom?
Just spin the SC the other direction :D:D then the inlet will be the bottom and the outlet will be the top :D


By the way. That is an EXCELLENT setup. I admire everyone who attemps SC or TC a Non turbo FC and the ways they fabricate everything. Great work to you and most everyone else out there that has done similar.

Justin

Mage 04-05-04 09:52 PM

what year tbird can I get it off of?



Mage

knightryder83 04-05-04 10:26 PM

zbrown please explain how you mounted the s/c with a better picture(possibly with the s/c off so we can get a better view of the bracket)

poor_red_neck 04-05-04 10:33 PM


Originally posted by Mage
what year tbird can I get it off of?



Mage

Early 90s

Ford thunderbird, and mercury cougar... same car basicly. Pretty sure they put it on a few other motors.

scathcart 04-06-04 12:53 AM

I don't understand why everyone is jumping all over this.

You can get a used stock turbo for $150, fab up similar piping adapters, and then have the same concerns with regard to fuel, intercooling and timing as exists here, and also get a more efficient compressor, and not gain any parasytic loss, AND have much easier upgardes.

Costs of the projects would be identical...

rotarygod 04-06-04 01:09 AM


Originally posted by scathcart
I don't understand why everyone is jumping all over this.

You can get a used stock turbo for $150, fab up similar piping adapters, and then have the same concerns with regard to fuel, intercooling and timing as exists here, and also get a more efficient compressor, and not gain any parasytic loss, AND have much easier upgardes.

Costs of the projects would be identical...

An Eaton supercharger does not need any water or oil lines plumbed into it. That in itself is much less work. The stock T-II exhaust housing is so pathetic from a flow standpoint that there is alot of loss through it when you could be getting a gain from a good set of headers instead. It takes a T-II a couple of psi of boost just to get back to equal power of no turbo. That sounds like parasitic loss to me.

Yes turbo upgrades are easier. I will concede to that. This is just far less work. A T-II turbo would also need a new downpipe made and a spacer to make it clear the lower intake manifold. No more emissions control or 6 port actuators either. I don't see any way that this isn't the best upgrade for the money. There was never any claim that it had the most potential of any mod.


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