Twin screw-vs-Centrifugal superchargers. What are your thoughts?

[rocket 5979]

Ok here i am yet again posting another thread in my neverending attempt to gain more knowledge for modding my explorer for more horsepower. What i want to know is which supercharger you prefer or have had good or bad experiences with? This can either be from a manufacturer standpoint or from a design standpoint. I see that alot if not all the people on here that have superchargers have centrifugal superchargers. I am wondering why some of the people that have the four door automatics dont have the twin screw type s/c being that is makes its boost at a lower rpm(1500-2000 r.p.m. range) and also unlike the eaton (roots) type s/c it doesnt produce an excessive amount of heat. Also what is better in your opinion for 0-60 times and 1/4 mile times with an auto tranny? Any educated replies would be helpful to both me and to any other person out there having this same debate before investing well over $3000. Here is a good link to a great website for info on superchargers.

Dead Link Removed

Thanks.

 

[DLN1223]

Personally I love the low end power of a roots blower. Had my first taste of it in my dad's 00 Lightning. THen once they released the cobra with the same blower. I handed over the keys to my 00 GT and stepped into the SVT club. From the moment you hit the gas pedal a lil hard you hit the boost instantly, make the car a real last to drive. I know it's not quite the same as an explorer but I figured it'd be in the ball park.

 

[Alec]

I have an Eaton M62 roots unit on my truck and love it. You're right that the roots types do make more power (torque) down low. They're also in general more reliable and easier to maintain and live with. Centrifugal units in general are better for the top end and sometimes have a bit of lag. On the other hand, they're much easier to fit an intercooler to. But the key to centrifugals is to "tune" the type of unit you get to the motor and your needs. If you pick it well, it can be just or almost as good for low end power as a roots.

1/4 mile times will vary greatly with the type of blower you get and where they make their power. roots will probably be the most consistent and will get you off the line, but tend to have less at the top end than the centrifugals.

alright, I'm tired and don't feel like writing pages. Short story long, my blower is great for overall power, towing, racing, and offroading.

 

[rocket 5979]

What about the twin screw type superchargers? Does anhyone have any thoughts on those?

 

[Alec]

you mean the whipples? i hear they're similar to the eaton units, but tend to be more efficient.

 

[rocket 5979]

Hmmm the way it sounded when i went to superchargersonline.com was that the roots and the twin screw were similar in design but that they are different. both types produce low rpm boost but i keep hearing that since the twin screw is directly inputting into the intake versus roots which compresses then through the plumbing inputs that compressed air into the intake which by having to revac or recompress or something the air gets alot hotter in the roots units where as the twin screw does not.

 

[rocket 5979]

i also heard that with the twin screw you dont have to relocate so much stff in the compartment as you usually do with the roots blower. hey alec besides troll which i know has a centrifugal s/c do you know of anyone else on here and what type of s/c they got?

 

[Alec]

pur pony, 5.0 with a centrifugal. paul bredehoft had a vortech on his 4.0 but sold it.

 

[rocket 5979]

i would think being that alot of us have heavy automatic tranny driven suv/s would opt for a roots or twin screw but it seems like alot of people put the centri s/c instead. i wonder if the centri has better average 1/4 mile times than the twin screws? all in all i am going for 1/4 mile times. so whether it is centrifugal or twin screw i am still deciding. i have ruled out the 347 swap for the time being. but i am leaning towards a s/c and alum. heads, cam possible intake if s/c doesnt replace it, exhaust, mas, and maybe TB too.

 

[Magicfan25]

Ok, as per the twin screw and roots thing. They are both positive displacement blowers. They will both require the same basic type of rerouting of things, they both sit directly over the intake. The main difference in them is the type of "rotor" inside it. I'm not sure off hand, but I believe one has two rotors that each have fins on it resembling that of screw or a drill bit ( read curbed around the shaft) while the other has two rotors with rows of straight fins around the shaft of each rotor.

The twin screw is more efficient. It has lower intake temps and produces more boost than a roots type with the same size pulley

I'll have to read this again tomorrow and probably edit some stuff...too tired right now

 

[james t]

ummm, understand noone makes a twin-screw for your X. only charger we have now in kit form is the powerdyne. and before you start considering using a 5.0 stang 2screw on your X, find someone with a 88-93. there are alot of accessory differences between the two. as far as twin-screw vs. eaton debate, muscle mustang did a shootout a while back. basically, twinscrew spanked eaton/roots. the 2screw put out colder boost @ same poundage than the eaton, and the eaton HAD an intercooler under it. eaton's are great all around, but the autorotor design IS much more effecient, puts out much cooler intake charge. 6lbs @ 130 degrees is worth more than 6lbs @ 250 degrees...

 

[rocket 5979]

hey james no one makes a kit for it using the twin screw but are you also saying that there is no real easy way to modify a twin screw to fit an explorer. could you take a guess to say why thes companies have not made a kit for the explorer? i mean it is not like the X is a race car sure enough of that. but with the 5.0 i would think there would be more mods like that that could go both ways.

 

[Magicfan25]

its not that you cant make it work. You have to come up with an intake adapter. Usually the upper intake, and sometimes the lower intake as well have to be thrown away. Then you you have to re route your incoming air into wherever the inlet may be on the blower. Seems you usually have to relocate some things here and there, but nothing major. Also you have to have a "fake" pulley setup usually, which is a metal bracket with two pulleys on it so you can propery run the accessory belt to run the blower.

 

[james t]

rocket- i really dont know how hard it would be to adapt from 88-93 stang kit. all the accesories are in different spots on the X, and we have the DIS ignition instead of a regular distributer (thank you, Ford ), so you may need to relocate that. look at the no longer offered Eaton on www.explorerexpress.com and you will see what im talking about. as for why no one makes blowers for the 5.0X except powerdyne, i have a few guesses. 1-the dont sell anywere near as many units as other vehicles, and no one wants to research/develop a kit only to sell like 15 of them a year... twin screw would definatly kick major ass in an X, due to the massive cold boost at lower rpms.

 

[rocket 5979]

WOW LOOK AT THIS!!!

Hey i was looking online and i found something pretty interesting. i was wondering if anyone else has found this? take a look at the price differences at the kits! i dont think i missed anythign, so i dont think there is a difference in the kits. it is jus that one is from the powerdyne proficient performance store and one is straight from the proficient performance store. here they are take a look. proficient store page

powerdyne store page

 

[rocket 5979]

at first i thought it was the same page but they arent. i think it is pretty cool. i just kind of stumbled upon it.

 

[james t]

Ford racing performance parts has them for $2600...

 

[X-Box]

Hey James,

I looked on Ford Racing and couldn't find a supercharger for the Explorer, only the Mustang and Lightning.

I am very interested in the "Twin-Screw" charger for my X. Could it be that difficult to change the accessories to accomidate the charger? Dom

 

[rocket 5979]

me too

 

[james t]

if you do a part# search, it will be M-6066-E50 for the 96-97, E51 for the 98, and E52 for the 99-01's. as far as adapting a 2screw from the stang, i really have no idea how you could do it. plan on AT LEAST major machine shop time to build acc. brackets... the FMU should work, as those just run off of a vacuum line.