intake plenum size.....
intake plenum size.....
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Joined: Dec 2003
Posts: 4,534
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From: Vestal, NY
Hey;
The net result of most people fiddling around with what Porsche hath wrought is a car that runs like scheissen! Particularly in the NA ranks, they have already done 95% of what can be reasonably expected. In the technical sense, there is no one place that Porsche has left a lot on the table to be had. That is not to say that "improvements" cannot be made, but they are so infinitesimal compared to what it takes to render and quantify them (fabrication and dyno costs) that it is an utterly futile endeavor.
That, or it's so rediculously expensive... You can take a 2.5NA and go from 147 to 180-ish. I wager it works out to somewere North of $100 per Horse!
Not to say it might not be an interesting escapade, but... Myself, I would rather spend my time driving.
The net result of most people fiddling around with what Porsche hath wrought is a car that runs like scheissen! Particularly in the NA ranks, they have already done 95% of what can be reasonably expected. In the technical sense, there is no one place that Porsche has left a lot on the table to be had. That is not to say that "improvements" cannot be made, but they are so infinitesimal compared to what it takes to render and quantify them (fabrication and dyno costs) that it is an utterly futile endeavor.
That, or it's so rediculously expensive... You can take a 2.5NA and go from 147 to 180-ish. I wager it works out to somewere North of $100 per Horse!
Not to say it might not be an interesting escapade, but... Myself, I would rather spend my time driving.
Race Director
Joined: Oct 2001
Posts: 10,033
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From: Houston, TX USA
A short runner, large plenum intake should provide some gains, but I'd guess the biggest place to find gains on this car (and really open it up to gains from other mods) is the cams. I had a friend who is connected with a west coast header manufacturer ask for the cam specs. He said it's no wonder doesn't respond well to mods. That said, Jon Milledge is able to get 185bhp from an IT legal engine (very limited mods), so there are gains to be found. But as John H. said, it comes with a price tag. I'm really surprised no one has tried the JME cams.
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Instructor
Joined: Jan 2003
Posts: 131
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From: Winston Salem
I've got a spare N/A intake laying around as well as the stuff to fabricate a new one so expense there is not an issue. I also already have control over my fuel (MAF/piggyback) and ignition timing. My thinking was to remove the horse shoe bend (the stock rubber hose) and make the intake more of a straight shot into the plenum/cylinders. It's always been my understanding that an N/A engine in general is more sensitive to flow restrictions than a boosted one. A cam was also next on the list. I think once I've opened up the intake track to a smoother flow (my exhaust is already done) the cam and head would be last.
Another question. What is the maximum RPM this engine can safely take? Is the stock redline it or can it be twisted to 7000 with no problems?
Heck, tinkering is part of the fun!
Another question. What is the maximum RPM this engine can safely take? Is the stock redline it or can it be twisted to 7000 with no problems?
Heck, tinkering is part of the fun!
Race Director
Joined: Oct 2001
Posts: 10,033
Likes: 1
From: Houston, TX USA
I would guess (and admit it's purely a guess) that a cam would do more for NA performance than anything else. As I understand it, the valves need more overlap before any big gains can be made.
