kc5zom

I think he's trying to tell you that it is a waste in money to get a port and polish on a stock engine (which it is). Why not invest that money elsewhere. And enjoy getting your bottom end done. The slightest threat of getting my bottom end done adds 30-40hp (at the wheels). Ok. Smartass time is over.

Hate to say it but I'm torn between supercharging and turbocharging. They each have their charms. I say go turbo if you are going to pursue lots of power. Go super if you just want some easy and reliable extra power

Traveler

You're thinking of a centrifigal supercharger. A positive displacement blower (roots or screw type) is capable of producing full boost from a very low RPM. They are driven off the crank but don't take that much to drive. Yes, it's possible to have one that needs 400 HP to run. But that's on a 3500+ HP drag engine.

A small Eaton would work well on our engines. They only need 7-9 HP at full load to run. At highway speed they only use a few tenths of a HP since they aren't compressing anything and they have fantastic bearings. They will use more HP for higher boost, but you can only realistically run 8-9 psi on a street engine anyway without intercooling. It's very hard to package any kind of cooling between the blower and the intake manifold.

I've heard various things about them on a 2.0L. It looks like 5 psi would make about 145-150 wheel HP, and they'll do slightly over 200 at 9. By the time you get to 9 however, you better have good fuel management as you DO NOT want any pinging.

The best thing about them is that you have all of your boost by approx 2200-2300 RPM. The engine basically drives like a much larger engine. The major downside is that once you have one, the only way to make more power would be to port the head, larger throttle body, larger exhaust and then you're done. Can't keep upping the boost levels.

The best thing about them is reliability. The ones that Eaton sell are good for way over 100,000 miles. That's why so many automakers use them as original equipment.

Traveler

Went junk yarding yesterday looking for used speed parts. I was looking for used turbos to see what might fit in the space we have and have close to the correct trim for our engines. Volvo has some pretty decent stuff and they don't have weird exhaust housings like so many of the other manufacturers do. I looked at ones from Volvo 740's and 850's. Small enough turbine that it should spool quickly, but has a large enough compressor so that it will move enough air to have fun with. Cost is approx $500 for a used turbo. i'm not sure if I would buy a used turbo though as I'd worry about it coming apart. Never know how the car was treated. Eclipse turbos are rare in these parts. They go out the door as soon as they come in.

The really interesting find was all the used superchargers out there. Eaton made a TON of superchargers for GM and Ford. I found 8 blowers from the GM stuff (3.8L Buick/Olds/Pontiac). It is basically an M62 eaton with an internal bypass so that it takes very little power to run when cruising. They are about $700 used from a wrecking yard and you'd have to make a manifold. The M62 will work on engines from 2.0-4.0L according to Eaton. The M45 is slightly smaller and works on engines 1.5-2.5L. The M62 will definately move more air though. I'm going to call Magnuson today and see what they charge for a rebuilt and new Eaton M45 and M62. They are the only authorized rebuilder for Eaton in the U.S.

chdesign

There are many things you can do to up the power of a turbo car without upping the boost. Experiment with different intake piping Diameters, Different intercoolers and different turbos will make different HP numbers at the same PSI. I agree reliable power is a eaton roots blower but eaton can suck my *** as they fired me so NEVER buy anything from them put the bastards out of business....sorry my little vent part....but roots blowers are a good alternative to turbos awesome low end but the top end is good but not as good as with a turbo.

Traveler

I'm honestly beginning to think about putting a used/rebuilt Eaton on my car. Magnuson says they'll make pulleys to my specification, and I can pick up a used M62 from a 1st gen Buick/Olds/Pontiac for $300-400 off ebay. From several people I've talked to, the stock Eatons need almost nothing if they even need anything at all. The bearings are the only thing they may need. Talked to one place that works on them and they said that for 150 superchargers that they've done, only one was damaged enough not to be used and that had a piece of metal stuck in a rotor from a motor grenading. The case was still good. I can make a sheet metal intake and make a bracket to lower the alternator. Shoot, I might be able to put it all together with an extra injector and an FMU for under 2 grand! Neat thing about those superchargers is they already have a bypass valve. Don't need to buy an external one or fabricate brackets for it.

GNO

I don't know about the older GMs with a supercharged 3.8L, but the current ones use an M90 not the M62, and they blow directly into the manifold (no IC). If the older ones did use the M62, they probably are mounted the same way and are also without and IC. However, the Ford Thunderbird Supercoupes used the M62 in earlier models and then moved to the M90. Since the output comes out the top and then goes to an air/air intercooler, the supercoupe may be a better choice as a donor vehicle since less fabrication would be required.

If anyone is interested in picking up an M90, a few Grand Prix owners will be upgrading to M112s and Blowzillas (Kenne Bell). I have a feeling that there will be a lot more M90s on eBay in the next couple of months.

Traveler

The 1st gen 3.8 (93-95) used the M62 and they were built with an internal bypass. That makes them a good candidate as they can just be adapted to a manifold. They are the right size for the motor, and the physically are smaller than the later M90's. They are a good match for the 2.0 is you want it to stay efficient and not lose much power to heat. The M45 would work also. Wouldn't be a good choice for trying to up the boost though.

The output on the Supercoupes is still on the bottom. The supercharger has no internal bypass and that's what the extra external plumbing is for. That's the reason this is not as good a candidate as the GM as there would be a lot more fabrication involved.