breaking belts, parasitics and side loading of the crank are reasons I'd stay away from a supercharger.
superchargers need to be spooled up to make max power, just like turbos, only a superchargers spool up time is dependant upon the time it takes the engine to rev.
A superchargers power delivery is more linear than a turbo chargers, but, understand that means it makes increasinly more power as rpm riases, where a turbo can spool... now... and make more of it's power sooner. That means a turbocharger has a better chance of making more average power than a supercharger... even tho it might 'hit' with it's delivery.
The 'hit' however is dependant more on the design of the individual system than it is to blanket statement. Good comparison is the current silky smooth Volvo turbo making max tq at 1800rpm, or, any of the diesel trucks on the market making max tq dang near off idle. You'll not get that with a centrifical supercharger.

Add to all that, a turbo does not need to rob engine power, and you've got a clear winner for making more power with a turbo.

The bad on a hair dryer is cost and custom fabrication... where most huffers are a weekend bolt on for half the cost.
Either setup is going to involve fuel and ignition considerations.

edit: no expert, just things I've learned having been around both setups in the mustang crowd

 

I saw an epicode of 2 Guys Garage where they installed a turbocharger on a Camero. The neat part is that it was located at the very back of the car behind the rear end. They just took the muffler off and put the turbo in it's place...then ran a long pipe up to the engine air intake. Mind you this was a fuel injected car... I don't think you can just ram pressurize air into your carb.

I imagine the long intake runner would act as a sort of intercooler. Also this way the heat from the turbo is not in the engine compartment.

They gained about 150 HP.

 

Yeah, A good twin turbo setup on a V-8 is hard to beat. Power comes on pretty quick, but a Roots style blower comes on quicker. Almost from idle, and can peak at a low rpm. Perfect for a truck. I'm not sure how much tow weight a Lightning is rated for, but I used to tow a boat with my 99 L. The load weighed well over 7000 lbs, with the boat, trailer, gas, and beer. The trailer is set up so I have at least 1000 lbs sitting on the ball of the hitch. If I nailed the gas with the boat on the back, that Eaton blower would start singing, and the back tires would just boil. You can imagine what it was like with NO boat being towed. People just couldn't believe it had that much torque. Would a turbo do that from a dead stop? I haven't seen one that could duplicate that powerband yet, but they could be out there. Sure a roots blower peaks at a lower rpm then a turbo, but my truck would run at 140 mph on cruise control, with the A/C and the tunes cranked. And that was bone stock.

 

haha, I agree.... that show is just craptastic, but they are very smart, and do the jobs they do correctly. the acting is a bit.....cheezey.

I can see some bennifits of this turbo in the back thing, but tell you the truth, if they put it closer to the intake, with the proper size front mount intercooler, they could have gained power simply by means of having less pressurised intake piping. not to mention the likely hood of blowing your exhaust pipes out due to exessive back pressure.

 

Steve,
Those lightenings are wicked trucks.
If I had the $$$ I'd be in one.
Guy at our track had slicks and a smaller pulley, and was running 12.7's... :shock:.
roots blowers make great tq.

 

ok,thx all,ok,would it be posssibal to run the turbos directly off the exhaust manifolds??i mean like bolt them directly off the studs in the manifold?and would ya'll suggest a inter cooler and where does this go,cuz i already have the tranny cooler and the radiator,hell idk,but i mean and wut ya'll mean by ignition and fuel set up,and is it possibal to make ur own bonnet?

 

opinions anybody?

 

yeah,if you connect the air supply coming from the turbo to an intercooler you cool the air and it becomes a lot more dense.when it goes into the cylinder in addtiton to the fuel it helps to make a bigger bang.some adjustments will be neccessary to maintain effecency,i.e.:fueling system,ignition,exhaust system,ect.

 

You wouldn't have enough room to just bolt the turbo to the stock exhaust mannifold. You could have a really nice set of turbo headers built for your needs, just visit your local speed/performance shop, they have lots of ideas as to how to giterdun. I bet if you did a search on turbo manifolds for your motor on google you'll find SOMETHING. I have made lots of thoughts of doing this, and keep telling myself to make it safe before you make it fast. so big power is still quite a ways away for me.

check out the book "Maximum Boost" by Corky Bell, really, by the time you are done reading it you'll completely understand how everything works, and you will either get turbofever, or totally give up on the idea all together. your local library should have a copy, if not then ask if they could get a copy so you don't have to pay for it.

 

Hey you old Guys are pretty smart! Wait a minute Old is relative to your basis for comparison. Turbo/Super, they both make more power right. Lets all get along now. Everyone has something to learn or they wouldn't be here!
Cheers.

 

yeah,i agree with ranger240.you will need to change the headers.it's what i was meaning when i was descriding the upgrades for your engine.i should have said it when i wrote my last entry and it's got me looking like an idiot.as for you 68 mercury,you could read a good manual on charger systems.turbo's get more power applied with less maintanance work involved.when it's in-it's in.almost no work or reworking is involved in the upkeep of this system.anyways my truck has completed a rework job.i put it in to remove a supercharger and to replace it with a singular turbo system.anyways,a guy who lives nearby had a lincoln mark 7.his has a 390 c.i. like my truck.he was to get a twin turbo setup put in.anyhow he wrecked his car.talk about an idiot wrecking a awesome piece of machinery.i ended up geting the twin turbo setup that was to go to him.i'll be taking the truck and be putting it through it's paces soon.

 

A 390 in a 84-92 Mark VII? He must of had fun getting it in there.

I'd like to see a pic of the supercharged 390 that you have in your truck.

Patrick

 

Almost no upkeep or maintanance? Hmmmm. I don't agree. When is the last time you've seen a turbo outlast a roots supercharger (for performance use). A turbo uses the engines oil supply, and you have to keep that oil changed. Then the bearings start to get loose, and your engine's oil gets sucked through the turbo, making the engine smoke like crazy. An Eaton supercharger has it's own oil supply. If you change it every 25,000 miles or so, the bearings will last as long as your engine. My SuperCoupe had well over 100,000 miles on it when I pulled the engine, because of bad head gaskets. Even the original blower belt was in great shape still. How would a turbo require less upkeep? I agree they make more maximum power, but a turbo on a gasoline engine lives in a very hostile enviroment, spinning at impossible sounding rpm's. Much faster then a Roots blower spins at. Now a centrifugal blower is a completly different story, but I don't see any upkeep nightmares. As far as a 390 in a Mark VII? I would need to see it to believe it. The front suspension would have to be all custom, as well as the engine mounts. Then to get all the cars electric accessories (speedo, cruise) to work without the computer would be next to impossible. I've been trying to work out the bugs for a year with my carbed 347 in a T-Bird SC (same basic platform as a Mark VII). Then there's the problem of getting the factory self adjusting shocks and suspension to work with the extra weight on the front, and without the computer. I don't think the independent rear suspension half shafts could take the abuse of that kind of power. An old style 9" would need to be swapped in. The 390 is taller and wider then any engine ever offered in a Mark VII. I'm not saying it couldn't be done, but would anybody go through all that. Except for maybe to have a strictly race only vehicle. Please show a photo.

 

Lets See Pics!!!!!!!!!

 

Turn your exhaust manifolds to face forward (swap them right side to left side), then create some kind of adaptor plate to mount the turbo's to them. Then all you gotta do is make some kind of pressure box for the carb, and route the air flow into it. Sounds like it would be a hoot to drive.