Questions about roots Blowers positive displacement

[Dominic Torreto]

So, I am planning on getting an 871 blower for my mopar. It has 8 to 1 compression pistons and I am buying an aluminum head for it. So this car could hold up to boost at 5k or 5500k. I was just wondering do these forms of aspiration have oil return lines? From the Dick Landy books I have read they dont. The rotors just need to be greased. I also was wondering if The dyer kits include the fuel lines for the Carbeurator. I also was wondering if an 850cfm carbeurator would be a good choice for an 871 at 5k or 5500 rpm limit or should I use to 850cfm carbs? Last but not least would I need a new fuel pump or could I get by on a stocker fuel pump at the rpms mentioned?

 

[HEMI-ITIS]

Need more info on your engine to make an educated reccomendation:dink:

 

[RustyRatRod]

An 8/71? What are you buildin? Even the most radical 440 can get by with a 6/71.

 

[Hemi Rebel]

True, a 671 would/could make plenty of power, but there is an idea behind using a bigger blower. They dont have to work as hard, thus generating less heat. This in turn makes more power. Either way, this stuff is expensive. Unless you have a half a clue, an amazing job, sell drugs or have a trust fund in your name, most kids in their early 20's would be hard pressed to have a charger with a 440 ,much less an extra 10 grand on top of the 440. Stock fuel pump? Really? You gonna run bulk 3/8ths rubber line too?

 

[RustyRatRod]

I think this is gonna go about as smoothly as the chick thread.

 

[Hemi Rebel]

I think this is gonna go about as smoothly as the chick thread.

you ain't kiddin'. :sSig_lol3:

 

[67 coronet]

to answer your questions.
1)would take about 1035 cfm minimum to run a 440 with an 871 huffer to 5500 rpm in street trim.
2)those blower designs use oil in the end cases,no feed lines.
3)fuel line hook up and delivery(yes a custom pump is required)will be completely custom to your application.
as said above,this is by no meens a minor modification and will require a great deal of cash and knowledge to put together.

 

[Dominic Torreto]

I am not going to go with high boost gentlemen. I should be fine. ALuminum heads and 8:1 pistons.

- - - Updated - - -

thats only 5-7 psi of boost.

 

[RustyRatRod]

You seem to be in the know, so go for it.

 

[Meep-Meep]

This guy I knew in the 80's put one on a pretty stock 383 and from what I know the conversion and end result wasn't bad. The car wasn't exactly our flagship of power but it looked sort of cool and that's all the guy wanted anyway. But with 2.76 gears (later moved up to 3.55 when the tubs went in) he drove it everywhere except the track! We used to give him so much crap it's unbelievable but he took it in stride. However the clamp on wheelie bars (over the brake line) and the wired on chrome rear end cover was just too much to stomach. I think he should have been a Chevy guy but somehow ended up with a MoPar. So with that said I'm sure you can pull it off if you stay on the safe side.

 

[99ss]

8:1 on boost.. what octane you using?

 

[rev.ronnie]

Gear oil in the drive housing. I like Synergen Syngear 2.

 

[RustyRatRod]

With an 8/71, it won't be the manifold pressure to worry about, but the volume. With 8:1 compression, you're going to need race fuel unless you severely under drive the blower. Then, what's the point other than looks alone? Seems like expensive eye candy to me. Why not put a 6/71 on it and under drive it around 3-5% and you can run pump swill all day long with a good boost timing retard. You might not even need it.

 

[HEMI-ITIS]

Bigger blower,spin it slower as the saying goes.:headbang:I have a 1071 stage 3 on a 540 inch hemi.10% ud gives me 5lbs of boost which equals a little under 800 HP.I can't wait to feel 10 lbs of boost!!!:blob1:

 

[RustyRatRod]

Show off. lol

 

[HEMI-ITIS]

Yea well:icon_hang: 5 lbs is still on pump junk:naka:

 

[RustyRatRod]

Yea well:icon_hang: 5 lbs is still on pump junk:naka:

Well your car is total awesomeness. I wish I could see it in person. I'd be showin it off, too.

 

[67Satty]

There was this guy back in the '80s in the Minneapolis area who used to swap a 6/71 blower on top of whatever beater he was driving at the time. One week at the strip (Rock Falls) he would show up with it on a rusty '69 AMX he had, the next time he'd show up and it would be on a rusty '69 Dart with a 440. The Dart also had quarter windows made out of cardboard and yes it would pass tech and they'd let him run.

There was also another guy that had a beater '73 Challenger. He was a bus mechanic for the MTC (city bus). He took a blower from a bus and put it on his Challenger. He even figured out a way to use the clutch from an A/C compressor to make it turn off and on with a switch ala Mad Max.

All this stuff sounds like tall tales and made up BS even to me as I type this but this is the kind of stuff people did back then. There's other people who were there that can back up my stories.

 

[Hemi Rebel]

I dont believe the clutch operated drive gear. All the air going in the motor has to go through the blower. Unless its really really loose and will freewheel, or the clearance between the gears and the case is so great the air can get around them. But then it wouldn't be able to make boost. Or not until like 8 grand.

 

[67 coronet]

I dont believe the clutch operated drive gear. All the air going in the motor has to go through the blower. Unless its really really loose and will freewheel, or the clearance between the gears and the case is so great the air can get around them. But then it wouldn't be able to make boost. Or not until like 8 grand.

i know a big time car junky here in town that made it work on a small block mustang.ya,the free wheel was a super loose blower.was able to spin with just the air flow of the eng running.he did it just to see if he could.blower was driven by an electric motor off to the side of the block.if you looked at it from the front,the drive belt was off at a 30 degree angle.rode it the car once and turning on the blower didnt do much at all,was all about the"if he could do it"thing.