Gday

I have a 1990 TP with a dual throat weber. The air filter is about 6x8". When over 3000rpm the air rushing through the filter screams loudly...which is kinda cool. Neways my car has been tuned but it still running rich when reving over 3000 (I can smell it and there is a lot of black splashback from the exhaust even when warm), could a larger airfilter reduce the force needed to suck the air into the carby, making the car run more even (in concern to richness) through higher revs?

I have a bonnet scoop, is there much to be gained from directing the air flow to directly onto the carby instead of just into the engine bay?

off topic but.... BONNET SCOOP????? post pics


Tim

Yea id love to see a pick of a bonnet scoop on a TP! My bonnet has rust spots where some of the welds are and I could cut most of them out if I was gonna put a nice scoop in there.

i think u r on the right track, larger airfilter will lean it out a bit at higher revs, provided of course your exhaust is up to the extra flow. Venting/scooping air straight onto aircleaner is definitely the way to go. all older ferraris do that. A small lip in bonnet to catch water and not run it onto aircleaner when its raining is a good idea.

I'll post some pics when I find my digi camera. I think I'll spend a day modifying the scoop with a pipe to blow directly onto the filter. Its got a 2.5" exhaust with extractors so its up to a bit of extra flow.

Where the hell did I put that camera....

Ok I found the camera. Its raining down here so its a little dodge but U can get the idea of the scoop

Noooiiiiiiice!

It will be your carbs running rich, if you already have a hi-po airfilter on it then there is only like .002% to be gained (as apposed to the stock .003% to be gained from a pod) Its just something you'll have to deal with or have the jets changed to a mildly smaller one. If it is indeed running rich then your losing performance and ur engine will be running cold and unefficient aswell so rejetting cant hurt one bit and you'll save some petrol. Have you got any friends with a A/F meter? perhaps a worthy investment if u are trying to do the work yourself

As above Turbo Charade is 100% correct.

Get the thing tuned !

Cold air induction like a bonnet scoop is the best performance gain as it allows cooler air to enter the engine and when cruising a positive pressure onto the air filter.

Hence why CAI kits have been around for so long.

will you guys come with me to ask for my money back for my K&N then? :redface:

for .003% i dont think i got much bang for buck lol

ill say its worth 3 cents not 300 bucks :bowrofl:

first mod? POD! :nuts: :bowrofl: :bowrofl: :bowrofl:

Im going to get it tuned next week sometime, I'll post how it goes. Would it be worth getting injection put back on? If so, roughly how much would this cost?

for .003% i dont think i got much bang for buck lol

All NA flowing an engine can do is to try increase the VE (volumetric efficiency). This is generaly around 85% for a multi valve engine. The VE is a ratio of combustion chamber pressure at btdc and the atmospheric pressure. NA flowing can only really get it to about 90-93% at extreme cases where internal flowing has been done. A pod filter will not help it five tenths of fcuk all.

How does this effect an engines performance? the pressue inside an engine at btdc is directly linked to its power and torque. More pressure equals more air which therefor can be fueled at the ideal rate and more power can be made.

good post explaining VE as the main factor in increasing performance, but not really why the pod isnt effective. for me im not sure how much difference if any the pod makes. i think on its own without any otheengine work probably next to nil. thats why driving with no airfilter dosent increase performance :doubt: noticably.
BUT, factory airfilters are selected for the iar requirements of a stock motor, when u start to work the engine thereby increasing its VE, the air and fuel requirement is greater. this is why airfilters must be larger or better flowing. V8's have airfilters twice the size of 4 cyl's because they require twice as much air and fuel. when u start to increase power from a NA engine which is mainly achieved by increasing air flow, the airfilter is an important link in the chain and when air and fuel requirements are significantly increased the filters flow ability needs to be matched to keep up.
when someone farts u pull your tshirt over your nose so you can easily breath filtered air through it, wheras when you have a panic attack you grab a paper bag and breath into it so that air is very restrictedand wont pass easily through. that is the basic of why a cotton pod like Dragon or K&N claims to flow better than OE paper filter.

btw when a piston is at below top dead centre (btdc) the pressure has dropped from the combustion chamber but is spread in the cylinder, the pressure is really in the combustion chamber when the piston is at tdc :cool:

Found 5 c in my pocket...
Any improvement with the intake airflow would reduce the pressure difference between atmosphere and cyl head channels/cyl. But I think more relevant with pod is where does it "suck" the air. Is it real CAI or hot engine bay air? Why "suck"? Cos engine doesn't really suck, only provide negative pressure for the atmospheric pressure to do the rest of the filling.
Well, actually, if it is a 3.8 V6 Dunnodoor engine, it does suck. Big time. :bowrofl:

3.8 V6 Dunnodoor engine, it does suck. Big time. :bowrofl:

How do you's put your magna's above a commodore? they are both cheaply built family cars
:confused: im not a commodore lover or a magna lover, nor ford for that matter but i would rather drive a rwd car any day of the week, therefor ford gets my pick due to bulk torque and more power than any commodore of its year, and magna for that matter

with that siad i drive a charade :P and wouldn't buy any of the above 3 mentioned if i had the money.

Sorry Turbocharade, but the SOHC 12v 6G72 3.0l V6 ****s over the 3.8 commo motor whether you like it or not.

RWD/FWD is just a preference as they can both be set up to handle like slot cars, that's irrelevant.

Sorry Turbocharade, but the SOHC 12v 6G72 3.0l V6 ****s over the 3.8 commo motor whether you like it or not.

RWD/FWD is just a preference as they can both be set up to handle like slot cars, that's irrelevant.

And thats a fact :D

And Killer engines do suck air in. Yes they do provide negative pressure wich draws the outside positive pressure in, thats what sucking is, also known as vacuum :D

Bit like: "which one was first, the chook or the egg"
But - hmm, which one is greater force? The atm filling up a vacuum or the mass of air moving in the cylinder with speed of piston? Piston speed obviously relates to revs and size etc. Where as atm fills up a vacumm with speed of ~ 330 m/s.
Gosshhh - that gave me headache.
Could we rather talk about chicks or something easy? Oh, that would make me a sexist....
Shut up K! :redface:


And thats a fact :D
And Killer engines do suck air in. Yes they do provide negative pressure wich draws the outside positive pressure in, thats what sucking is, also known as vacuum :D

Bit like: "which one was first, the chook or the egg"
But - hmm, which one is greater force? The atm filling up a vacuum or the mass of air moving in the cylinder with speed of piston? Piston speed obviously relates to revs and size etc. Where as atm fills up a vacumm with speed of ~ 330 m/s.

It's the one force, the greater the vacuume the higher the speed of cylinder filling. The motion of the piston moving down creates the pressure difference (vacuume) witch sucks the outside air witch is at atmospheric pressure in. :P


Gosshhh - that gave me headache.
Could we rather talk about chicks or something easy? Oh, that would make me a sexist....
Shut up K! :redface:

Yes....chics are good lol

hey its just like the question of how te universe got started, answer is with THE BIG BANG from the spark plug lol

Air speed filling a vacuum is ~ 330 m/s
Piston speed is ~ 26 m/s on hi RPM (Ruffly, couldn't bovve calculating now).
There is some diff there. So, air is way much quicker. NA engine only, of course.


It's the one force, the greater the vacuume the higher the speed of cylinder filling. The motion of the piston moving down creates the pressure difference (vacuume) witch sucks the outside air witch is at atmospheric pressure in. :P
Yes....chics are good lol