Made my own induction kit,

[johnjohnson]

i know many people say keep the factory box. but then others have fitted an induction kit. so i thought id at least give one a try.
instead of buying an expensive one i just bought a gineric one and bodged it, in a proffesional way of course.

however, the mistake a made was the pipe diameter, it is 2.5 inch, whereas stock is 3inch.

then i found a link about pipe diameter, and that if you use a too large diameter it confuses the ecu etc.

the car has always, in my mind, been a lil slugish below sat 2000rpm ish, both before and after the kit fitted

just wondering what peoples thoughts are. ill get a picture of the kit, and car as soon as i can

thanx

[Robin H]

Theres nothing wrong with diy parts as long as there done well and quality parts are used

The only way to tell if it's had a good or bad effect is on a dyno

and I never find myself driving my car under 2000rpm

[Moe]

I was using standard airbox with a HKS Hybrid panel filter. Then I removed the airbox and fitted an Apexi cone filter.
Low down torque was like a 1 litre fiesta, then after the VVTi it would go like a scalded cat.
Fuel consumption increased noticably aswell.
I now have re-fitted the standard airbox and HKS filter and altough the car is not as quick accelerating, the overall power delivery is much smoother and the fuel economy is improved.
If you like driving the balls off your car then fit a cone filter but if you drive (fairly) normally then stick with the airbox.

[ESXTEZZ]

Reducing the size of the intake pipework will loose you top end and mid range power but should help with low down torque to a point.
The best bet would be keeping the standard size intake pipe diameter, making it longer should increase low down torque whilst reducing the length should increase top end power. By increasing the intake air speed (longer pipe) better low down rpm, or reducing intake air speed but increasing flow (short pipe) alters your torque curve.
The standard airbox and intake pipe design flows really badly and is very easily improved.
By smoothing out the inside of the airbox (plastic ridges) and removing the flap mechanism in the lid and also smoothing that area aswell with a dremel will help a lot and increase flow and increase intake air speed, also seal up the hole in the side of the box which is fed from the inner wing as warm air will be pulled in through there.
Most of the aftermarket induction kits use a slightly bigger diameter pipe which the air flow meter fits into, this fools the ecu into thinking there is less air being sucked in by the engine at full throttle and lean the fuel mixture ( in theory improving power) as most cars run a bit rich top end.
I havnt tried it but i think the bmc cda would work well on an altezza if you can find space for it.

[lakers]

Reducing the size of the intake pipework will loose you top end and mid range power but should help with low down torque to a point.
The best bet would be keeping the standard size intake pipe diameter, making it longer should increase low down torque whilst reducing the length should increase top end power. By increasing the intake air speed (longer pipe) better low down rpm, or reducing intake air speed but increasing flow (short pipe) alters your torque curve.
The standard airbox and intake pipe design flows really badly and is very easily improved.
By smoothing out the inside of the airbox (plastic ridges) and removing the flap mechanism in the lid and also smoothing that area aswell with a dremel will help a lot and increase flow and increase intake air speed, also seal up the hole in the side of the box which is fed from the inner wing as warm air will be pulled in through there.
Most of the aftermarket induction kits use a slightly bigger diameter pipe which the air flow meter fits into, this fools the ecu into thinking there is less air being sucked in by the engine at full throttle and lean the fuel mixture ( in theory improving power) as most cars run a bit rich top end.
I havnt tried it but i think the bmc cda would work well on an altezza if you can find space for it.

BMC CDA??????

[ESXTEZZ]

Reducing the size of the intake pipework will loose you top end and mid range power but should help with low down torque to a point.
The best bet would be keeping the standard size intake pipe diameter, making it longer should increase low down torque whilst reducing the length should increase top end power. By increasing the intake air speed (longer pipe) better low down rpm, or reducing intake air speed but increasing flow (short pipe) alters your torque curve.
The standard airbox and intake pipe design flows really badly and is very easily improved.
By smoothing out the inside of the airbox (plastic ridges) and removing the flap mechanism in the lid and also smoothing that area aswell with a dremel will help a lot and increase flow and increase intake air speed, also seal up the hole in the side of the box which is fed from the inner wing as warm air will be pulled in through there.
Most of the aftermarket induction kits use a slightly bigger diameter pipe which the air flow meter fits into, this fools the ecu into thinking there is less air being sucked in by the engine at full throttle and lean the fuel mixture ( in theory improving power) as most cars run a bit rich top end.
I havnt tried it but i think the bmc cda would work well on an altezza if you can find space for it.

BMC CDA??????

http://www.bmcairfilters.com/carbon-dyn ... 3_4_1.aspx

[playtime]

Ive just spotted the bonkers prices of 'proper' induction kits for the lexus on ebay, with prices in around £240, for basically a long pipe with a small cone filter on the end, and a couple of jubliee clips. Now thats bonkers. Im going to have a go with the smoothing the inside of the standard box, and see if it makes any noticeable difference with my stainless exhaust fitted, but Im also thinking of making up my own pipework, and sticking on my trusty k&n from the old s14 warrier. But Im thinking of making my pipe at the filter end bigger say 90mm wide diameter, and having it shrink cone style down to the 75mm diameter of the throttle body. Im thinking this will speed up the airflow as it leaves the filter down towards the throttle body. Just curious if anyone has tried this, and did it work, or is my head up my ass as usual?