New air cleaner, new power!

[TulsaSpider]

Hi all! I just got my new lunch box air cleaner installed. I used a separate cone filter for the separator hose and I plugged the vacuum line for now. I adjusted the mixture out a little and went for a test drive. The change in power is very noticeable! I was happily surprised to say the least. It also has a better growl and look of course. So should I leave it like this or should I plumb the vacuum line in to the new seperator hose filter??
Wohoo!
Clark

[mbouse]

well, at least it sounds REAL GOOD, 'eh?

gotta love it.

[rlux4]

MORE POWER! ar, ar, ar!
Ron

[mbouse]

this is a feeling reserved for us carbureted guys. no offense, ron, but you fancy smancy F.I. dudes don't understand the sheer pleasure these minor changes in performance and perception our modifications can bring. i bet it will take a month to wipe the smile off Tulsa Spider's face .. dang, i love that feeling.

What's next Tulsa Spider? a new muffler, a new exhaust manifold? R R R

[manoa matt]

Tulsa,

You think you like the sound now....wait till you get on the highway and open up the secondary venturi. Smiling from ear to ear.

[rlux4]

Hey Mike, I'm older than you, I remember driving cars that had carburetors. It was sometime in the last century though.
Kidding aside; you have to keep in mind, my first Spider was a 79. A California 79! THE most gutless Spider ever made, and I'm in a state where you can't change it. So I'll take the FI, thank you.
Ron

[TulsaSpider]

New exhaust, yes is definitely needed. So should I leave the vacuum line plugged? Can I use this one for the Fiat E I system I am planning to install sometime?

[So Cal Mark]

I'd suggest you figure out a connection for the vacuum hose to the breather. This is a calibrated source that increases as the throttle opens and it's important to help vent the crankcase. A poorly vented crankcase can lead to oil leaks and sludge buildup. I know there are lots of members here that have just hung their vent hose down towards the ground like the old road draft tubes of the 40s and 50s. That's a poor way to vent the crankcase, and if you're old enough to remember those cars they suffered from drastic sludge buildup and worn engines at fairly low mileage.
In recent years Audi, Toyota and several other brands have had sludge problems all attributed to inadequate crankcase venting.

[mbouse]

Hey Mike, I'm older than you, I remember driving cars that had carburetors. It was sometime in the last century though.
Kidding aside; you have to keep in mind, my first Spider was a 79. A California 79! THE most gutless Spider ever made, and I'm in a state where you can't change it. So I'll take the FI, thank you.
Ron

i am happy to take you on a trip down memory lane.

tulsa has started down the fun and exciting journey of modifiations for the sake of fun and enjoyment... it's now a never ending quest to grab mo' power!!

[Kevin1]

Carb people have all the fun!
The best thing I can say about the Bosch FI is that it works. Not very tuneable, though.

[alexGS]

I can see both sides to the carburettor/FI argument

I think Bosch L-Jetronic FI is at its best when there's a turbocharger fitted, as in my Uno Turbo

I once saw a news heading, "Are carbs really bad?" Why yes, I thought, usually by the time they're made emissions-compliant, they're such a mass of pipes and solenoids that it's simpler to have FI. But then I found the news article was something related to the Atkins diet.

Anyway, I have a similar but different problem. I have twin Dellortos and Pipercross foam air filters. The noise is both awesome - and ridiculous. Never before has there been such a roar for so little power! I'm thinking of making some sort of box to enclose the foam filters. Maybe even a plastic box? What size should the air intake hole/trunking be? I was going to aim for something similar to that fitted on my 164, as if 50-odd mm is large enough for 2959cc, it must be large enough for 1995cc.

The Bosch Automotive Handbook reminds us of the principles of Helmholtz resonators (for tuning frequency response by chamber size, venturi length, etc) but that always seems like too much mathematics. Should I put some calculation into this, or just make it a bit bigger than the foam filters?

Cheers,

[sptcoupe]

Mark is correct abou the breather hose, so you should find a way to plumb that and get some vacuum on it. After 35 years of messing around with IDFs, I found the solution to keeping the noise down (but not smothering that great dual carb wail), while letting them breath fully. I have some photos of the intake sytem on my coupe somewhere, and on another forum as well. WIll try to post them when I get a chance.