Corky Bell's book on supercharging has an excellent discussion of this. Anyone thinking of porting or otherwise modding their s/c from stock would do well to read his book. Could save a lot of money and headaches.

 

Actually the teflon coating on the Ford blowers and the APC on the GM ones are two different animals. Please see my thread on peeling rotors, where BC describes the two and how they are different.

 

Just got off the phone with my tuner. He just tuned a lightning with a throttle body, cat-back, six pound lower, and stage 4 port. After icing the intake the best the truck could pull was 398 hp and 460 tq.

Good job stieg, got a real winner of a port job there.

 

Wonder how the "Revised" ports will perform. I do have to agree with whoever said that there are gains to be had with a port, but not with the Stage 4, lol. Hell, there's guys with Stage 3's complaining now. Maybe that's a question Brian can answer. How much material can be removed before losses take place?

 

Seems as though the stage 1 and 2 were sucesses, although I have a feeling I know of a couple that aren't. I will be testing the revised stage 4 port from this gentlemens truck. We'll see how they fix it. I also had him take pictures of the blower before he sent it out. I just want to make sure that stieg isn't replacing cases ( if he even has any) even though he says he can fix it by " re-clocking".

 

I'm kind of at a loss with this whole thread. My thought would be that the tighter the tolerences, the greater the efficiency. When using any tpe of mechanical pump, and I mean any, My experience has shown that the looser the fit i.e., rotor clearance, you end up with "blow by" making each pass of the rotor displace a smaller amount of air then it would with a smaller clearance. Just my thought. So the question of "how much material can be removed before losses take place?" I would say any at all.

The only thing I think to truly be gained, would be maybe, and I stress maybe, with that with a greater clearance, you may free up some air to surface friction allowing the rotors to spin a little faster with greater ease. This would free up some heat, allowing some additional timing to be thrown at it, but the amount of energy expended to create equal power negates the port. For the same dime you could lower IAT's with a less restrictive inlet or larger throttle body.

Again, this is just my $.02, nothing more nothing less.

 

Seems that there has been a few poeple that got the "fix" done and did not see any gains. I have asked Steig for an explenation of what he was doing to "re-clock" the blower, and never got a response.

There has been some track results that have been less than steller also....too bad the truth has come out, although it saves some people money.

 

I personally think it's great that some light has been shed on the subject. I don't like to see people waste hard earned cash, seeing as I know how hard some of that cash was to earn, lol.

 

just doing my part......Funny, I have been accused of not knowing what the hell I am talking about when it comes to these blowers.....I know alot of people here and on NLOC.org have been questioning my knowledge on "porting" the blower. The information that has come to the surface only backs up what I have been saying for years......It does not work.

I hope Bird sees the light now

 

You can say that again. Heres my original from over at the NLOC.

This is depressing. To start, I have a 03' Lightning with 30k on the clock. I ran last year with just an intake and FTVB, everything else was stock down to the F1s. I ran a best of a 13.6@102 with a 2.19 60' with the other runs in the range of 13.7-14.0, with the 14.0 being the slowest with a crap *** 2.3 60' and it about 78 degree weather.

Over the winter i added this; E-fan, TR6's, Lakewoods, new fuel filter, LS oil seperator after full IC cleaning, 555Rs and most importantly a Stieg stage 4 port/rotor strip, and on top of all this, i removed the front sway bar and dropped the spare tire, which i didnt do last year.

These times say it all...
LAST YEARS BEST:
2.19 60'
13.62
102.84

LAST YEARS WORST:
2.23
14.04
100.01 (In 80* weather with terrible launch on F1s)

THE BEST TONIGHT:
2.08 60'
14.004 1/4
99.07

THE WORST TONIGHT:
2.14 60'
14.056
98.64

Now, i made 7 runs here guys, so that gives you an idea on how consistent i was running. Disturbing, to say the least.

It was 50* out, 44% humidity and clear and crisp out, even with a real slight tail wind.

Yes, the 60's are a issue by itself, with the 555R, i get them warm and experimented from anywhere from a launch from idle to taking it to like 1500 and stabbing it. At no point did i roll the throttle or spin, i stabbed it and left, i see no room for improvement there, and even still, a 1.9 60' wouldnt get me better than a 13.9.

Now, im sure im going to get alot of guys saying "put the 6# on and go from there, thats when it will work out". I dont believe that and thats malarky in my opinion. Ill throw the 6# on and be so impressed with the increase in power that ill assume the port helped, when in reality i might run faster without the port and the 6#. This has brought me to a major crossroad.

I had issues with the port from the beginning, as most of you know based on my initial post. I had installed/removed it 7 times within a month and I dont see more than 8psi of boost. Then i order my Xcal2, MAFia and 6#er from a vendor here (not Stieg related) finally after 2.5 weeks get the MAFia and Xcal2 with no pulley. The pulley has yet to show up after almost 3 weeks AND to boot the Xcal2 didnt even come with the tunes that i apparently waited 2 weeks for! I am highly concerned with the way this is all panning out, and im on the verge of selling anything i can to return to stock and leave it at that. Im not trying to throw anyone under the bus, im not mentioning the Vendor and im not bashing Stieg. Their customer service was great, but i think maybe i just got a bad one, all i know is i do 100% regret the 640$ i put into this blower, just to get negative results. Everyone says "dont jump to conclusions, take it to the track for real results", well, i did, and im not satisfied.

Sorry for the ran this took. Its just after spending over 1500$ i expect some type of results.

Let me know any input you guys have, i also have all the rest of the meteoroligical facts about the night also, in case someone wants to blame the weather.