LAT

I have 1997 C4 Cab with the Aerokit I spoilers that I am making some minor changes to and I am trying to decide between the "intake trumpet aka IT" part #993.110.360.51 and the Fabspeed open airbox lid. I have both but I cannot tell the difference by seat of the pants. There is an experiment in p-car.com where the writer finds 6 deg cooler air with the IT versus a standard box. I emailed and he had not tested the IT vs the open airbox.
The basic argument here may be as simple as air temperature vs air volume.
Anyone else compare these two, your thoughts.
Thanks<a href="http://p-car.com/diy/intake/" target="_blank">Intake Air Temperature Experiment</a>

993RS

That is a tough one. I have the intake trumpet. I read the experiment, and since the intake trumpet is so inexpensive, I got one. I was considering a drilled airbox, but the increase in hot engine air deterred me. What I wonder is why Porsche has neither intake trumpet nor an open airbox/drilled airbox on its Cup cars... Maybe because it does not really make much of a difference?

LAT

[quote] why Porsche has neither intake trumpet nor an open airbox/drilled airbox on its Cup cars... <hr></blockquote>

I thought Porsche had the open airbox on its Cup cars..ie. the Carrera Cup hi-performance cover..at least that is what the open cover ads claim..javascript: x()

I have just ordered a G-Tech to do my own experiments and look forward to comparing the three versions, the open the drilled and the intake trumpet.

I can say that the trumpet is the most pleasant to drive with, as in quiet.

I am suprised at the lack of responses to this fairly important topic. Intake covers are one of the first things people make changes to. <img src="confused.gif" border="0">

993RS

With the minimal differences, do you really think the G-Tech can detect these? Aren't they within the margin of error of repetitive runs?

Macca

Good question raised here:

The ad claims these were used on supercup cars. They were as far as I can determine used on supercup 964 cars!

As we all know the key hp difference between 3.6 964 and 3.6 993 has been largely contributed to "exhaust and breathing" improvements in the 993.

My thoughts here are that the 8hp that was expected as an increase using the open airbox cover on a 964 is not an 8hp increase on a 993!! The 964s benefit to a greater extent from such modifications as they are a bit more restricted in the first place.....

If you read through the *ab*peed* site more closely you will see the 8hp referenced to the early 90s cup cars...

Cheers

Macca the Kiwi

LAT

[quote]Originally posted by 993RS:
<strong>With the minimal differences, do you really think the G-Tech can detect these? Aren't they within the margin of error of repetitive runs?</strong><hr></blockquote>

993RS, good point, I agree it will probably be within the margin of error but I can't seem to find any real dyno data, ie. dynojet or mustang on the 993 mods, only hearsay. I am also going to try the Andial 2 deg block.
I have done and continue to do a lot of modifications on Harley Davidson engines and the final step in tuning is always setting timing and jetting using a dynojet dyno. I have seen over 5% imporvement in this area alone. I imagine if the 993 can take the extra advance and the ODB II can correct the fuel needs then we should get some benefit. I will post the results.

tom_993

If you are interested in the open airbox lid, try this. It’s virtually free and easily reversible. You can see if you like the sound and/or alleged power improvement.

Brett - 1996 C4

Tom:

Are you using the Mahle paper filters with the airbox lid off? I'm thinking about what happens if it rains.

Brett

tom_993

[quote]Originally posted by Brett-1996 C4:
<strong>Tom:

Are you using the Mahle paper filters with the airbox lid off? I'm thinking about what happens if it rains.

Brett</strong><hr></blockquote>

It’s a stock filter, whoever makes those. If it rains, put the cover back on. It only takes a minute or two. I don’t think any water will get in anyways, but if you are concerned about it, I’m sure you could “invent” a rain cover fairly easily.

Georges Rebeiz

Guyzs

can you install the trumpet and perforate stock box at the same time?

Thx
Georges

LAT

Yes, I have the Motorsound airbox with the air trumpet.

chris walrod

anyone have pics of this trumpet? I would like to have a look at it. I work with the engine builders of the Toyota Atlantic series. They are constantly playing with trumpet designs. Maybe I could have one of them take a look at a picture of this?

RT7

I had the trumpet but I went and replaced it with the *ab*peed open air-box that I bought from you (LAT). I didn't noticed any performance difference but the sound did improved. <img border="0" alt="[byebye]" title="" src="graemlins/wave.gif" />

LAT

If you look at pictures gallery attached you will see the air trumpet installed in my car.

<a href="http://gallery.rennlist.com/gallery/albun72" target="_blank">http://gallery.rennlist.com/gallery/albun72</a>

viperbob

Levino,

Do you know what the problem is with adding a new part to your car? It makes all the other parts look dirty. You either have to remove your air box and clean it, or dirty your new airhorn prior to installation.

Just kidding, it looks nice.