What you've stated is correct, and here is the reason why: Screw and roots blowers are positive displacement blowers, meaning that at idle, they are huffing air. The centrifigal blowers do absolutely nothing at idle, other than act has a shiny cork in the air intake system. They require some RPMs before they start to pressurize the air. You can change this to some degree by using a smaller pulley, but you'd just kill your performance at redline because the centrifigal blower will have maxed out a little before that.

Keep in mind that any of these supercharger kits change and modify many, many components and systems in the vehicle, and those modified systems have to work together before and after you put the kit on.

Forced induction of any method is a complex thing to do, whether you buy a premade kit like the KB, or put it together yourself with steel plate and junkyard turbos.

As far as doing it yourself, thats a personal decision of course and no one will fault ya for wanting to have it done by a pro, right the first time.

But look at the fun hkiefus was having over a pinhole. A friggen pinhole! Do you think a "Pro Installer" would have found that any faster?

I'd say not. hkiefus's testing and diagnostic procedures were right on, and I'd bet he's a "regular guy" like you and me

 

hkiefus, Every time I think about you fighting this thing to the ground I have to laugh... have you had any more Problems? I hope things are running good for you.

 

Not a single problem. The KB kit is everything it is claimed to be. Now that I've had some experience I'm working to get it even closer to perfection. The KB programming is a bit conservative (more fuel and less ingnition lead than necessary).

I think I noted earlier that I ran it without a chip for a short bit, and while I did have mild ping at the top, it has a LOT more power.

Of course being the person I am, I have been getting my education before I act. I'm not afraid to spend the money, I just don't want to waste it. I'm not excited about the possibility of shipping a chip back and forth until I get it just right. I want to gather the data I need and burn only once or twice.

I gather that just about anybody can burn a chip for fuel curve based on a broad-band AF graph from the dyno, but I'm curious about how we go about determining spark advance. I've got an active post in the 'chips' form asking this very question. If my research is correct the knock sensor is present but not operational in my specific application. Without it if I get too agressive I will ping the ******* to death. On the other hand, if we can get it to work I can be more agressive with a 'safety valve' of sorts. The question is, do we keep advancing spark until we get ping and then back it off? And do this at every few hundred RPM in the operation band? Sounds like a waste of time or lack of effort, I would think there is a better way. Also, is it reasonable to assume I can get away with more ignition lead in cold weather than warm? So, do we program for max heat and just loose the extra performance in cold weather? I would think the programming would take into account IAT input but I understand that only fixed tables are used under WOT operation.

Do I have enough questions? Sure. Am I having a ball learning it all? You bet! I'd guess that I can be a reasonable asset to any board members who install a KB unit, especially if it is on a Navi.

 

This is one of the best threads I have ever read. (and thats alot)

 

All I can say is WOW!!! I gotta tell ya, this was one awesome thread that not only gave insight into the particular application but the way to go about eliminating possible issues to get to the root cause. Nicely done

 

I dug readin ur adventure, i am lookin into the kb myself what did it run u 4 the kit and do u know if kb installs there units at there shop??

 

You can get the kit for about $3,600 $3,800. I don't think that KB will do the install. The most famous KB installer is Kennedy's DynoTune http://www.kennedysdynotune.com. You should be able to find a competent installer in your area.

 

I'm interested in buying the KB kit for my 2000 Expy. But on their website, the kits are shown as 6psi, even for the 4V Navigator motors. How are you making 9psi? Did you special order a 9psi kit?

The other option I'm looking at is the new intercooled whipple kit which claims 8psi of intercooled boost which theoretically should make a lot more than the non-intercooled KB, but they're projecting the kit to come in around $5500 and they're still not out yet.

 

A slightly smaller pulley on the S/C is how I get the extra 3psi. If I had the option of an I/C I would have taken it. Although, I must say that I'm only increasing my IAT by 57 degrees. I'm not trying to get every last ounce of power out of this thing, rather just very stable 'enhanced' operation. For example, I did about a 50 mile run tonight at 90-95 with a group of sports cars. Without the S/C the Navi is quite laggy at that speed. Even at 9psi on a 90 degree day I don't have any problems. I have 30K on the motor now and have not had a problem.

 

Here's something interesting. The KB kit for the 2V Expedition/truck comes with 8 upgrade injectors, whereas the 4V Navigator kit makes you reuse the stock injectors and gives and FMU instead.

I think I'll go KB. The kit's been out for years and their chips are most likely dead on. The first group of whipple kit buyers are going to be the guniea pigs for tuning.

Here's something even funnier. Whipple can't crack the GM computers. They offer a piggy-back computer with 2 additional injectors in a throttle body plate like a wet nitrous system. Well KB started selling just the reprogrammed ecm and injectors to whipple owners who wanted to get rid of the crap fuel system on the whipple kit.

http://www.kennebell.net/accessories.../Piggyback.htm

 

Hello to another supercharged 4V owner

Just read your thread hkiefus, you have done some impressive diagnostic work there...

You should be able to set it up to run it with a more aggressive spark advance when it is colder (mine is set up that way).
If you can do it really well, you can have a threshold ping %. Mine is set up at 0.15% on both heads.
Anything over that and it starts retarding the spark, and increasing fuel.
I also have it set up for when it starts getting a little hot (as in the vehicle is going to overheat) to alternate elimination of the spark in each cylinder.
Saves the engine that way!!!

BTW mine is intercooled, and on a 100F day, intake temp is about 150F.

 

People are reverse engineering those already.... maybe KB should visit diy-efi.org... LMAO

 

Hey big F350, I sure wish I could get an Intercooler for mine, was your's custom fabricated? Also, I wish I could find a tuner that would take as much effort as to tune of different IAT, they just seem to want to put a few degrees in take a few degress out across the whole band. I'm envious if you can't tell. Green with envy in fact.

 

No, mine wasn't custom fabricated.
Check this site out...
http://www.capa.com.au/kits_ford.htm

 

Ah, you have a centrifugal SC. You are able to do the plumbing. Mine sits on top of the engine and there is no manufacturer that allows me to place an A-W IC in mine.

By the way, any idea of what the octane rating of Shell V-Power is down under? Also, is it non lead, low lead, or leaded?