Scott Injection: HUGE update

Post by **FalconGTHO** » Fri Nov 22, 2002 4:18 am

A Roots is the least efficient as far as power produced to heat generated. Centrifugals make more HP at the top end and have a HIGHER top end that positive displacements s/cs. Thats why they are used in drag racing. However, they trade off low end torque and immediate torque off idle, thats why I think they suck for the street. The best for the street is a screw compressor. They dont have the pressure pulses like a Roots and they heat the air less because the screws dont "beat" the air like the lobes in a Roots do. New Roots deisgns such as the Eaton used in the Cobra do a better job because than the 6/71 style because the lobes are twisted which reduces the beating effect plus the tolerances are machined MUCH closer.

Post by **FalconGTHO** » Fri Nov 22, 2002 4:24 am

Thanks Mitch. I havent looked at manifolds for Cleves since I dont have one nor a replica project in the works. When you buy a 6/71 (or ANY s/c) the manifold is included unless youre getting some ghetto garage sale/swap meet thing. Go new, go complete. BDS, B&M, etc. With that the proper manifold will come with the package for the price quoted.

Post by **PULSE** » Fri Nov 22, 2002 4:37 am

Thanks Falcon, That's pretty much where I was getting to... And besides if you've got it why would you ever want to shut it off...LOL But seriously would it really be much benefit in a street-able version to shutting on and off? I mean if the engine is built for a modest amount of boost what would you achieve by being able to shut it off, other than a thin wallet and a bunch more to go wrong....? Let it spin, let it spin, let it spin..[/font]

Post by **FalconGTHO** » Fri Nov 22, 2002 5:09 am

Well, switching it IS cool. Think of it this way. You have a strong, quick, hot engine. THEN you add in the power of an s/c on demand. Its like mechanical nitrous without the danger of destructive detonation.

The only problem is, the hotness of engine is limited due to the low compression needed to work with forced induction. So, yet another reason to NOT have a switched s/c.

Post by **Brianesff** » Fri Nov 22, 2002 6:53 am

I'm not going to get into a lengthy rebuttle at this time concerning FalconGTHO's ignorance. I have worked out all the problems mentioned on the board today and will answer any questions asked by those other than FalconGTHO.

Fuel pressure can be boosted by an electric pump or by introducing boost pressure to the diaphram of a mechanical fuel pump. Hollow brass floats need to be changed to Nitrofil type and a hydraulic throttle cable in needed to completely seal the air box around the carburator. FYI, the airbox is nothing new. It has been used on carburated engines with other type forced induction systems for years.

The heat generated by any type blower is a concern. I would like to run an intercooler, there's enough room for one but they are expensive. Fortunately, it's something that can be added later.

I've read all about the MR2 supercharger. See it here,

http://www.mr2.net/

It used a ROOTS style blower. Not centrifugal. The performance was not great and the whole system was overly complicated. An electric clutch engaged the blower but one like it wouldn't be powerful enough to turn a 6-71.

Post by **Mitch** » Fri Nov 22, 2002 2:43 pm

Brian,

Have you put a pricetag on the setup you have described? What about the reliability/ease of maintenence issues? (Honest questions, not digs.)

Obviously, I'm working towards having a functional blown 351C in the Falcon. I'm old school with the technology and a purist with the looks, but I can compromise if it means performance. I'd much rather have a functional, streetable non-authentic but close blower setup vs. a totally authentic non-functional mockup.

As far as the heightened tensions on this (and other) thread, my 2 cents is that we all have a common interest, but different opinions sometimes. Let's focus on what we enjoy together, and not make judgemental statements on other's ideas and statements. A more diplomatic method of interaction is in order, I think. I like to come here for the ideas, discussion and fun. I get enough bickering in the outside world, don't all of you? In the immortal words of Jim Carey, "Can't we all just get along...?" LOL!

Falcon, How close is the B&M setup lookswise to the Weiand Nostalgia 6-71? It's been awhile since I looked at their flyer, and I'm too lazy to go to their website. Besides, I want opinions!

Mitch

Post by **5.7 Interceptor** » Fri Nov 22, 2002 8:58 pm

Heya Mitch, the B&M blower housing is very different and what you actually want is just a plain GMC housing which is what was used in the movie. The only thing from weiand is the drive (front cover)

Like Brian said earlier, Terry James at madmaxcars.com has heaps of them last June and I'm sure he could supply a very usable core for you to get rebuilt. Most blower manufacturers have their own castings these days but you should try calling them to see if they have any 'plain GMC' housing still around... I'm sure they do.

Doug

Post by **Mitch** » Fri Nov 22, 2002 11:45 pm

Doug,

Thanks for the info. Since I bought the Falcon fron Terry, I'm sure he'll give me a HUGE discount on the blower casing (wink-wink).

Installing a functional blower opens up a whole can of worms. You can't put out that kind of horespower without beefing up the tranny, u-joints, driveshaft and rear axle to handle it. The weak link will give out at the most inopportune moment, leading to potential catastrophe. Can't impress the chix when your C-4 is spitting shrapnel... And then you have to stop the damn car. Rear disc brakes, or an upgrade at the very least.

Still, and no reflection on any of the fine Interceptor replicas, I have to have a car that will live up to the reputation.

Mitch

Post by **Brianesff** » Sat Nov 23, 2002 6:50 am

The price tag is going to be high for a functional blower no matter what you do. The Weiand supercharger kit that came with the car is about $3000 new.

Like Doug, I'm also a purist about the look. The most recognized feature about the car is the blower set up. The first time I saw the movie I thought it looked ridiculous sticking that far out of the hood. The look has grown on me since then.

My Weiand was the new style with a different front cover and drive. It really doesn't matter what brand you start with, to be correct you need to locate the old style Weiand front cover and drive. I found mine on Ebay. Doug's website has the best pics available for these parts.

A functional blower will be hard because the Scott injection was designed for drag racing. It's really not a streetable set up. I've thought about converting the Scott set up into a throttle body and adding fuel injectors to the manifold ports like many EFI designs. No matter what you do, fuel injection is going to run into thousands of dollars.

One of the other problems with the Scott is that there is no easy way to filter the air. Dirt, water, bugs and low flying birds will be sucked in. A screen is used to keep out the big stuff but everything else that goes through will shorten engine life. Some type of filter should be used after the blower.

I don't think reliability is a concern, even with a full time blower. Maintenance will be similar to any engine but realistically, how many miles per year do you think you will drive one of these? What are your specific concerns?

If you are not a Scott purist, there was a rare carb made by Ford in the late 60's that I considered. It was called an inline 4V Autolite, made in 875CFM and 1425CFM versions. They pop up on Ebay occasionally.

They are expensive because of how rare they are, but would be infinitely easier than making a streetable Scott Injection. The Inline carb is the same overall shape as the scott hat. Very cool if you have never seen one. A pair of Weber carbs inline is another option.

It's impossible to have an exact Scott/Weiand like the movie car. It had no throttle cable, fuel line, or bearing plates on the blower.

"I'm working towards having a functional blown 351C in the Falcon. I'm old school with the technology and a purist with the looks, but I can compromise if it means performance. I'd much rather have a functional, streetable non-authentic but close blower setup vs. a totally authentic nonfunctional mockup."

Ditto.

How much money is in your budget at this time?

"Installing a functional blower opens up a whole can of worms."

You better believe it.

Post by **FalconGTHO** » Sat Nov 23, 2002 9:09 am

Ignorance? Sorry to say but p i ss off mate. Im a prior ASE Master Recertified technician with an Associate of Applied Science in automotive tech so dont smart off.

Be sure to post full details and pics of your switched blower and fully function vehicle powered by it upon its completion. Really, if this coudlve been done, it already would have. Theres no need or reason for it and that adds to why it hasnt been done yet as well.