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Roots would produce more than the other types of SC, a quick google search yields LOTS of information.

MK

well it's not a typical roots. it's an eaton so it's got the spiraled rotors which makes it more effcient, so it wont produce as much heat as a normal roots. It'll still be hotter than other things but not as hot as a normal roots.

I thought I had hit submit on this reply earlier, obviously not.



Anyway, I have decided to put the MAF sensor pre-blower because i have to take into account the 4 blowby lines or whaterever they are called that currently go from the heads, and sensors and what not that go into the current NA intake. The exhuast that is recirculated into the system is filled with oil and crap, and that would go all over the MAF sensor insides. Not good.

Kelly - Air temperature is measured by the MAF sensor but it's only used in calculating overall mass flow. The only signal that leaves the sensor is a voltage quadratically related to mass flow. The ECU doesn't know anything about intake air temperature.

That's why changing turbos or installing an intercooler really should be accompanied with a change in engine management; the stock ECU is calibrated for the amount of heat the stock turbo with stock boost control and stock piping puts out.

Even if the ECU did get a temperature signal from the MAF sensor, it wouldn't be very useful, since the temperature can change hugely between the sensor and the intake valve, especially with forced induction.

Douglas - There's no exhaust gas recirculation on your engine, and the only sensor in the intake tract is the MAF sensor. But, yeah, the PCV issue is an important one. Forgot about that. I'm sure the sensor would be unhappy with a fine coating of oil.

I didnt mean exhaust exhaust, but the pvc stuff and the tubes that come out from the heads.


Well, I spent alot of time running around today. I did manage to get my intake and throttle body piping fabricated for about $175 total. This included having the modified aluminium intake welded ($30), the adaptor plate made out of steel ($60) and the exhaust shop made my intake piping for $75. Plus some parts from home depot $21.

Saturday will be the day!

SWEET.

I can't wait to hear how it runs.

Ok, I couldnt wait. I had to hook it up and "test" it and just see if it even came close to working correctly. IT DOES! Its unbelieveable. Even with it not having everything bolted tightly, and electrical tape as the hose connector between the intake and throttle body, it ran and idled (I did not drive it).

It did not idle well at all. But I suspect/know this was because of all the loose fittings and a single major vacumn leak. And the car will not idle period if the supercharger is turned off. It needs a supercharger bypass valve for when at idle or just off. It also NEEDS!!!!! a blow off valve because there is so much boost it is going to cause serious problems when you let off the gas. I do have a bosch blow off valve which is plastic and has some sort of electrical connection as well as a vacumn connection. I will need to figure out how it works!

However when you gave it some gas it just took off! I didn't ever even hit half throttle there was so much boost involved. I was hoping the boost guage I have hooked up to the throttle vacumn line would show boost but it did not so I have no idea how much boost is involved yet.

AND IT SOUNDS AWESOME! I was dissapointed when I was testing it in the last few days because you really couldnt hear it over the exhaust. However with all the parts hooked up, the exhaust and secondary noises quiet down and the supercharger sound increases.

Man , I can not wait! I give myself a 90% chance of having it up and running on Saturday.

F'n cool! I always liked the sound of a supercharged engine.

Steve

SWEET!

Oh, wow, that is just too cool.

I've never heard of a blowoff valve with electrical connections... The Bosch valves I've seen are functionally similar to stock Legacy Turbo ones; they use a vacuum signal to control when they open. Does the Bosch valve have ~7/8" connections? At right angles to each other? And a ~1/4" nipple on top?

That is the BOV. But it does have the wierd electrical connection. I tested it and it "clicks" when 12 volts are applied. This may be a secondary control of some sort.

Weird. Sounds like it's solenoid-operated too. Is this valve from a Porsche from maybe a decade or two ago?

No idea, bought off of ebay for $20?

Don't worry about a bypass valve at idle. Eaton blowers are designed to be, basically, off, when you aren't on the gas.

Look at the Ford Lightning and Mustang Cobra (03+). Good gas mileage because the blower disengages at idle and cruising. Basically it will spin enough to flow the proper amount of air required. Kind of like a clutch setup.

I don't know if yours acts this way because the pulley isn't stock, is it?

This is sounding awesome! I love the pics, the whole setup looks sweet. I'm with Phil, you shouldn't have to have a bypass around the supercharger. It should be designed to flow when not under boost. Could it be that since you currently have such a big vacuum leak that it's not drawing enough air through the unit to properly spin it at idle?

Hey Vikash, we should start working on Scott to supercharge his L!

An AWIC would be really sick on this, too if you could fit it. Since you wouldn't be on boost as often the water would always be cool and you could probably get away with a small tank.

Steve

Yeah, I'm with Steve!

I was thinking before about a way to make a cheap AWIC... If you're doing custom piping anyway it might fit in well.

Try to visualize this:

You get a large tin can.
Cut both the top and bottom off.
Now drill a bunch of holes in the top and bottom, matching them up so both have the same pattern.
Also, cut holes in the side of the can and attach water inlet and outlet fittings.
Then reattach the top and bottom to the can, lining them up so the holes match. Some type of soldering or brazing ought to work well.
Cut a bunch of lengths of thin-wall copper tubing.
The tubing's outer diameter should be equal to the diameter of the holes drilled, and the lengths should be equal to the length of the can.
Stick a length of tubing through each hole in the top and bottom.
Solder/braze them as they meet the ends of the can.
Attach a funnel to each end of the can to act as an end tank.
Cut each funnel at the appropriate place to achieve the desired O.D. and solder/braze a short piece of pipe as a place to attach a hose.

BAM!
vrg3 cooks up another fine dish!


...and perfectly describes how the head of my water cooled glassworking torch is put together.

That'd be one hell of a homemade piece. I like it. Then all you need is a place to mount the little radiator/trans cooler...

Bosco - Hah.... I'm a better cook than Emeril, too.

That's cool to know that someone actually uses a device like this in Real Life.

So anyone wanna take on the burden of prototyping the unit? I was thinking some high-temperature solder would make assembly really easy. I don't know where to get thin-wall copper tubing, though.

Here is another solution for an air/water cooler. This is how they cool beer without a fridge.


You simply encase the air intake inside another larger tube and run water through the bigger tube. Imagine running your intake through a muffler, but the muffler is welded tight to the intake and then plumbed for the water lines. Really simple. So simple I think I will try this!

That's essentially a degenerate case of what I described; just one copper tube.

It'll certainly flow extremely well. I'd be very interested in seeing if it cools ~200 cfm usefully.

You won't have the surface area of something more sophisticated, but you will have no additional restriction and where you're not running much boost or for long periods it might be all you'll need. It certainly wouldn't be hard or expensive to try.

Steve

The Bad news and the Good news.

Bad News.
Never Ever Ever stick a rag into the supercharger to protect it from crap, engage the electric clutch, then drive at high speed to Home Depot until the rag get blown out and sucked back in. Very depressing. Sad even, maybe a tear or two. No matter how hard you try, you cannot seem to budge the fucking charger backwards.


The good news.
If anyone ever wants to know how to disassemble a supercharger of the eaton variety, let me know. I tore it apart, pulled out the rotors, cleaned the rag shit off, reassembled it and as soon as I hit "submit" I will be putting it back in the car.


What a fucking idiot!