to super or turbo???

A

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i was wondering what option would be the better way to go...supercharged or turbocharged???...this will hopefully be added to the stang after i do my other performance upgrades like the full package azcoupe is selling on his site...my car will then be pretty modified so would super or turbo be better...if so what would be the model to get...???...any help will be appreicated...my football season is over and now i have the time to spice up my car...gary
 
8) i would use a turbo. build low end and mid range torque, and let the turbo build the mid range and top end power.
 
The turbo gives you better low end than a belt driven supercharger. The supercharger relies on RPM to determine the boost pressure. The turbo relies on exhaust gas flow.....id go with a turbo....
 
Emerald 74 4X4":2gjbmkxm said:
The turbo gives you better low end than a belt driven supercharger. The supercharger relies on RPM to determine the boost pressure. The turbo relies on exhaust gas flow.....id go with a turbo....

8) sorry, but it is the other way around, a supercharger gives better low end response, because the turbo relies on exhaust flow.
 
Depends on the supercharger too. A roots type supercharger, like the common as dirt eaton m90, gives you practically instant boost and is ideal for low(er) revving engines like the 200. The centrifugal chargers, like the votec v series are more top end, they are essentially a turbo driven directly off the engine instead of from exhaust gas pressure. Centrifugal superchargers spin at up to 65,000+ rpms , and don't deliver much flow at lower rpms. There isn't any lag like a turbo but it takes high rpms to move a lot of air. Roots type blowers only spin at 1.5- 2 times the engine speed, but those big lobes move a lot of air at low rpms, so, instant boost.
Turbos have lag. Big turbos have a lot of lag, but make big boost at high rpm. Small turbos have less lag, and make a less boost, sooner. Two really small turbos cost twice as much as one, but don't have very much lag at all, and spin up to maximum boost quick.
You can run a draw-through carb set-up with turbos and centrifugal blowers and get the car to run well. Those tiny vanes' ultra high speed atomize any fuel even thinking about staying in liquid form. They do a good job of turning water mist into microscopic fog with water injection systems, too.
Roots blowers are not so good for draw through. Unless the fuel is really finely atomized coming out of the carb (so a Weber, not a Carter...) some of it gets picked up at low rpms by the slow moving lobes and pulled out of suspension. It then pools in low spots, until enough intake velocity picks it up, making the engine go rich suddenly, surge-bog. A blow through carb in a box is the way to go with the eatons.
My two cents.
Rick(wrench)
 
depends on the turbo :D..but yeah..it is the other way....in a sense..i was thinking of the centrifugal blower when i wrote that....forgot about the Roots type...still..id go turbo... :D..less engine drag...no more belts than needed...the exaust is free energy
 
I keep wondering if you set up a supercharger(like a vortech) to put out 10psi at 2000 rpm then why cant you put a spring loaded relief valve to keep boost from climbing any higher. Yes i do see that there will be a small loss in friction from turning the blower faster than nessasary at higher rpm.
My thinking on this is that you can have more boost faster at a lower rpm and still not over boost at higher revs.
Jim
 
80broncoman":1db1aezu said:
I keep wondering if you set up a supercharger(like a vortech) to put out 10psi at 2000 rpm then why cant you put a spring loaded relief valve to keep boost from climbing any higher. Jim

It's not about boost it's all about RPM. Centrifugal blowers need to turn revs to make boost. If you belted one to turn 65,000 RPM in order to give full boost at 2000 engine RPM, when you got to 6000 engine RPM it would be tuning 195,000 RPM... for about half a second. Turbos have a wastegate to limit RPM, belt driven centriugals do not. You could rig some sort of a boost operated clutch to disengage at a given boost level, but why bother? Use centrifugals on the sorts of engines for which they were designed and use positive displacement blowers where they are more appropriate. Turbos work everywhere but one size does not fit all.
 
8) you can however use a popoff valve like indy cars do with a blow through system. it goes between the turbo, or centrifugal blower and does limit boost. however like SR said there really is no reason to use a popoff valve on a centrifugal blower.
 
But a popoff does not protect against over revving the turbo, it merely limits boost. If (and this is a very, very big if) you are sure that you have sized the turbine stage correctly and that you cannot over rev the turbo then a popoff is preferrable since it maintains turbo RPM even as it dumps pressure. If you're not so sure about your turbine sizing, best to stick with a wastegate which slows the turbo down as well as dumping boost. Neither of these devices will protect a belt-driven centrifugal against over revving.
 
Personally, I would do a turbo.

As far as low end versus high end. If the turbo is sized right, you can get a nice flat torque curve starting at 2000 RPMs. My Volvo turbo gets 90% max torque at 2000 RPM. Can't beat that.

I also like the fact that a turbo is load oriented, not just RPM oriented. that way, if I am on the highway, with no major acceleration, I don't want boost.

Slade
 
plus it seems that moding a SC to fit up to our sixes is a P.I.T.A. and could cost a bit more.

load oriented is a big bonus for town drivability expecially with a stick.
 
can i incorporate both super and turbo? like say a small turbo and a super...sounds liek it can work...what do you guys suggest???...i want to make a tricked out six to get more people interested in our sixes and stray away from the v8's in my area...gary
 
that sounds like more hassle than it's gonna be worth. I'm going to throw my hat in for the 'turbo' option. they're just more versatile and efficient. If you want to go more trick than just turbo, there's intercoolers, water injection, or both. Any way you go, it's going to take quite a bit of research and fabrication to get it to work. but once it works it will be sweeter than molasses.
Ern
 
Detroit diesel did a gear drive blower and turbo setup on thier 2 stroke engine....of course..it wa s 2 stroke deisel..but still....more positive intake pressure than just the blower itself.

I have also heard of using two turbos, one compressor outlet feeding another compressor inlet..there was a little special name they called it, but i forget what it was called. I dont know if it would work well or not..cause once it hit the second turbo, your pressure would decrease due to the restriction, although it is pulling air in. wonder if the outlet of the final turbo would be more thatn the first or double?..there would be no point if it didnt put out more...
 
stick with one, if it was a V6 a twin would be cool but ease of everything for the basic same results (our engines will only flow sooo well). use either a t3 or t3/4 hybrid, or the really easy and just as affective way is use an IHI turbo off a turbo coupe thunderbird, xr4ti, or svo stang (same engines in all). all are just the right size and easy to come by. you are going to need an upgraded (boost referenced) fuel system and some forged pistons if you want to run more than 8 or 10 psi as well. some people say you dont need forged but i figure the cost of fine tuning and still not being sure if you are hurting things is still higher than running some forged plugs.
 
Hypereutectic pistons have more silicone content and handle heat better...Learned that on this forum :D
 
what is azcoupe's site address? and belt driven S/C's provide lower temperatures
 
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