i have never really figured out why people put superchargers on their N/A's but putting a Turbo on one is soooo dangerous. other than the obvious difference in the amount of work it would take, they are both doing basically the same thing.... compresing air.

other than having less boost what is the big prob here???

once i get some 3mm on an engine after the one i am about to put in, i may decide to put a SC on there with another big SP, but would it help if i got some TII rotors with lower compression??

lots of questions, plenty of time...... its funny i havnt even finished my current engine and i am already planning on one after that..

Justin

 

good question. i dont see why you cant turbo an n/a and keep the boost 3-5psi

 

with a supercharger you seldom have to worry about the turbine overspinning (as long as you have the right size pully) and boost creap as turbos can sometime have problems with.

Generally you also don't have to worry about oil cooling or the oil cokeing (like you do in a Turbo if you forget to idle down before shutting off).

A supercharger is just a little more idiot proof.

 

does a SC require oil lines????? how much do people generally see from a supercharger w/ say a S-AFC on an engine currently running 235 bhp

Justin

 

You would think that with as much interest as there seems to be in changing to forced induction; that a company like Mazdatrix or Racing Beat would produce either a SC kit or a Turbo kit.

 

Volume.

 

I sit here with a completely stock car, and if a supercharger was available for the same price you can get a domestic one for - like $1000-$1500 installed, I'd have done that, an exhaust, an intake, and the fuel mods almost instantly - I mean what's $2500 when you can get 50 - 75 hp. (and after it cooked by auto tranny and rearend, those would've been upgraded, too).

But the unknown cost of fabbing everything is keeping me out of it. I bet that the volume would come from just 'vert owners alone.

What burns me is the Nelson white paper indicates that guy had a supercharger on an rx-7 and running in a day or two. So it must be easy to do. Maybe I'll go talk to scathcart some more.

 

Boost is boost. Doesn't matter whether it is from an SC or a turbo. Adding a supercharger is easier than a turbo, but also more "low tech".

3-5 PSI? yeah, for wusses. I'll be running 8-10PSI on my turbo NA when everything is said and done...

 

Some superchargers require oil feed lines and oil drain lines, whereas some are self contained.
What exactly are you looking to do, power wise? What will the engine have when you want to put on a supercharger?

I think the main thing is that a Turbo will not easily bolt on, you have to plumb wastegates, it involves a huge exhaust change, and there is more to worry about.
A S/C is pretty simple and easy when you understand them, and as Icemark put it well, are much more "idiotproof".
Sean cathcart

 

Is there interest in a s/c kit? I could make one for around $3000 (not much profit for me). I'd have to see a decent amount of interest, about 5 people or so, with cash in ahnd.

Really, just tell me what you are looking for in your car. I am looking to supply a lot of the things that aren;t already available to use.
I don't wanna get into c/f for others, its been done.

However, I can do what others won't.
Interested in anodizing parts?
Powder coating? (I may be doing a group buy soon)
Lemme know what you guys all want.

Also, check this **** out, if you'd help me out.
https://www.rx7club.com/forum/showth...threadid=72260
Post what you want here.
Sean Cathcart

 

Check this out.. many have seen it before.. its still an awesome imstall..

www.houston-rx7.net/forsale - look for the pics of the Red FC.

 

1989 Mazda RX-7 GTUs

Nelson Supercharger (50 state legal) Paxton SN2000 HO Blower with B&M Racing Cooler
Mariah Motorsports Naca Duct Headlight Cover feeds a K&N filter in a Mariah Motorsports Cold Air Box
High Pressure Fuel Pump
Mazda RX-7 Turbo II Fuel Injectors
Corky Bell adjustable Fuel Pressure Regulator
Jacobs Spark Plug Wires
HPC coated Mind Train Header
A'PEXi GT Stainless Steel Exhaust
Kosei S5R Wheels - 17 x 8 Front, 17 x 9 Rear
MazdaSpeed adjustable coil-over shocks
Suspension Techniques Sway Bars with Racing Beat end links
Mazda Competition Adjustable Rear Camber Link
Hawk Brake Pads with Mazda Competition Stainless Steel Brake Lines
Mazda Competition Motor Mounts and Transmission Mounts
C's Short Shifter
Tri-Point Engineering Air/Fuel Ratio Meter
Optima Battery Relocated to passenger-side rear storage compartment
ProDyno tuned, 223 RWHP.

 

You're getting it confused...
No one said NOT to turbo an NA - most of us said it's not worth it; it's cheaper and easier to sell the NA and buy a Turbo II.



-Ted

 

fortunately for me i can fab just about anything so i wont be buying anything but a supercharger and raw materials...

the car will have a fully tuned single outlet exhaust, intake, VDI, S5 internals, BIG street port and otehr minor things, but those are the biggies.

Justin

 

Depends on where you live. TIIs are super rare around here, so it would mean going to the states to buy one...Also, it depends on how much you already have invested in your car...It wouldn't make any sense for me at all to go buy a TII...

However, it is significantly easier to just drop the TII engine into the NA than it is to turbocharge the NA engine...

 

granted, i know this..... if i wanted a turbo i would just get a TII, so why is it that people supercharge N/A's how cheap can it be done for and what kind of gians are possible??

JU

 

Really, from you mod lsit, it depends on how far you're looking to go. Expect to pay around $3000 for the installation of a kit.
With a Haltech or the likes, and some low comp. rotors, you could make BIG hp, depending on how you pulley your s/c and what s/c you get.
If you want me to set you up with a system and then you can make the necessary parts, first tell me your power goals.

Sean Cathcart

 

I am hoping to get 195 to 200 rwhp all motor, then with a supercharger i hope to run maybe 10 psi and i would absolutely love to hit 300. i can prolly get a TII fuel pump and some bigger injectors. i can make pretty much anything.

the numbers i am shooting out are from Adam's and my calculations so we will see. i should have my new engine together either by today or sunday

dont know when i will get it into the car......

Justin

 

Surprised no one said this already.

Heat!

Turbos and superchargers generate heat due to compression of air, but far worse in a turbo because the entire turbo assembly is subjected to the heat of the exhaust. That heats the intake charge a great deal more than a supercharger does, leading to detonation faster in a higher compression NA motor.

Just my .02$

PaulC

 

I agree here with Aaron!

 

OK,
this seems like a good time to ask...
what size pulleys are these supercharger kits using?
I have a paxton head unit,got most of the brackets
fabricated...but I would like to know pulley sizes
to go with.....thanks

 

also what about pop-off valve?
read were nelson kits didn't come with them?

 

I heard it's nor cheap.&nbsp The Nelson "kit" was priced over $4,000.&nbsp Dyno numbers ran up to about 23xHP to the wheels.&nbsp Not bad...but for the price, it's about the same as a FC turbo with full exhaust (this should put out about the same numbers).

There is also the Camden kit that Hayes or Atkins sells.&nbsp I'm not fond of carb conversions...



-Ted