I tested my stock 87 Carrera before and after installing a nice pre-muffler. My results were 180 RWHP with the cat and 187 with the pre-muffler. I did not do a full power curve, just max HP, but wanted to at least chime in as one other person who has tested this. I also tested with the OEM muffler and with a performance muffler and actually lost a few HP at the top with the performance muffler.

There are a bunch of 3.2 owners in the UK who plan to do just that with the SW chips already purchased - its just a case of finding the time and organising the day. If you send me a PM I can give you more info.

Richard

The factory intentionally programs the air fuel ratios extra rich above 4500 rpm to prevent catalytic core meltdown under sustained high speed full thottle operation such as on the autobahn. The richer mixture creates a cooler exhaust flow which keep the cat cells cool, but this does nothing for power, and is not really a problem in the U.S. with our lower speed operation. Lean is not good either, such as 13.8:1 or leaner, but we are nowhere near that.

well, I hate to pee in cornflakes, but this is not a "controlled" experiment. You cannot change two variables. You cannot make a single run and declare much of anything. You need (at least) 3 points to make a straight line.

Interesting data points, but I'd be pretty hesitant to drawing a significant conclusion other than "it appears as though the second run has more hp/torque."

Wow, what remarkable restraint. No "Our SC's don't need no stinkin chips" comment... :)

:confused:
What confuses me is that Steve Wong makes these chips, and then relies on customers to get dyno results? If you are designing a chip for a car, and you are going to sell that chip, don't you put the chip in an example of that car and run it in on a dyno as a part of designing the thing in the first place!?!?! If Steve isn't designing these chips with the assistance of dyno testing, then what is he using? Divine Revelation? At the very least it seems to me that someone selling a go-fast part (especially one as easy to swap as a chip) would test the product on a dyno at their own cost for marketing purposes. Come on, three runs on any old carrera with a stock chip, swap'em out, and three more runs with the new chip. @ $150/hour for unlimited runs, how long could this take!?

I'm just baffled that this is even an issue, it seems like the dyno would have been used either for R&D or marketing.

Uh, not to pee in the cornflakes, but I believe 2 points make a straight line.

(Homer Simpson voice) Mmmmmmm... pee in the cornflakes....

There's stil no denying that when all two ( or three) things are done...as *most* owners will do...then the combined effect of those three changes produce the HP improvements shown on the dyno runs. Pretty good overall improvement for those simple three things....taken together.
I still think it's only an academic and thought-provoking issue taken in this context......
--Wil

I'm only a lurker in this chip dept.. so my remarks are only afaik. I'm replying 'cause nobody else has.

The A/F ratio constructs a flame that transfers energy to your piston. The larger the flame the more energy being transmited. Any max flame can be reduced by limiting the air or increasing the fuel. Auto engines operate rich of the desired max flame. There are many instances where a leaner mix will increase this flame from the previously constructed rich A/F, thus more HP. Another issue becomes the deviation between the max flame and the minimum flame among all 6 cyl. This may increase or decrease when adjusting theA/F mix in either direction.

The envelope is the CHT. A bigger flame is doable if the CHT remains within the desired envelope.

whatever. blast away

If you want a straight line with any hint of statistical information, you need at least 3 points.

Then again, in grad school I watched one of my colleagues draw a parabola using a single data point. And that point wasn't even the vertex. :eek:

And I believe that Homer prefers donuts to cornflakes :p

"What confuses me is that Steve Wong makes these chips, and then relies on customers to get dyno results? If you are designing a chip for a car, and you are going to sell that chip, don't you put the chip in an example of that car and run it in on a dyno as a part of designing the thing in the first place!?!?! If Steve isn't designing these chips with the assistance of dyno testing, then what is he using? Divine Revelation? At the very least it seems to me that someone selling a go-fast part (especially one as easy to swap as a chip) would test the product on a dyno at their own cost for marketing purposes. Come on, three runs on any old carrera with a stock chip, swap'em out, and three more runs with the new chip. @ $150/hour for unlimited runs, how long could this take!?

I'm just baffled that this is even an issue, it seems like the dyno would have been used either for R&D or marketing." - banjomike

Very well put! - a bit mickey mouse product development -

"well, I hate to pee in cornflakes, but this is not a "controlled" experiment. You cannot change two variables. You cannot make a single run and declare much of anything. You need (at least) 3 points to make a straight line." - nostatic

Another very valid & right-on post. I guess few have taken a data analysis or
statiistics class even in H.S.

not for nothing

I think it's disrespectful for any member to blast another for posting his insights. You don't have to buy into it, But what he sees thru his eyes are important imo.

[QUOTE]Originally posted by nostatic
[B]Then again, in grad school I watched one of my colleagues draw a parabola using a single data point. And that point wasn't even the vertex. :eek: [QUOTE]

You're making my brain hurt - how did he do that?

i agree with roninLB. the steve vs loren thing is getting a bit old. we're all entitled to our own opinion. both guys are way better at electronics than i am, and i appreciate hearing both their thoughts. i'm glad there's no one constantly countering me whenever i post. knock it off guys!

Well, regardless, what interests me is that the combo gives about 15 hp, which is consistent with what folks have been saying all along. I don't see much benefit in either as a stand alone, really. The motor is an air pump, after all.

well, he only got one decent data point out of the experiment, and he was trying to prove that his sytem exhibited "inverted region" electron transfer behavior. So he plotted the point, then drew a curve that "fit" the behavior he expected and went through the data point.

As my o-chem prof once wrote on an early lab report I turned in: "This is science, not science fiction."

Steve's a great guy who loves Porsches. I'd hate to say it, but selling chips isn't his main employment. For the prices he charges and the amount of custom work he does to tune cars, the price of his chips isn't going to make him rich. Having others report back dyno results isn't a problem for me. I think Autothority has there own dyno that they test on. I don't see too many users raving about their chips, at least not on this board.

You know, when all this first started I thought Steve Wong and Loren were the same person. Steve would post something, loren would refute it, then 30 satisfied Steve Wong customers would chime in and blast Loren. I thought it was the most unique marketing game on the planet...

Then I realized that all the happy customers were unique to each post.

I'll second that, but I can say I am trying to help him make chips his primary source of income, right Steve?

Personally, I would rather see independent dyno tests from a variety of sources than dyno tests done at a manufacturer's facility. I am firmly entrenched in this industry, I have seen plenty of products over the years make 5 horsepower in the ads and lose 5 horsepower on any dyno other than the manufacturer's own.

BTW Steve, I look forward to seeing you in a few weeks. The motor comes out Labor Day weekend and than the fun starts! You can fine tune my 3.5L twin-plug anytime on the road and dyno.

Ralph

I guess many dislike the constructive comments of Dickster, Nostatic, & Banjomike,
and as such ignore them and only focus on posts that support their views.
Remember, this is a forum where all views, either positive or negative, contribute
to enhanced knowledge for all.