Cold Air Intake
Author
Discussion

Gelf

Original Poster:

713 posts

229 months

Monday 22nd January 2007
quotequote all
I was suprised to see that the CAI is positioned facing up into the gap where the bonnet closes down onto and not into the mouth of the grill, its opening is so small in relation to the pipe from the air filter and the AFM.

Apart from drilling holes in the air filter box which allows hot air from the engine bay to be drawn in, are there any other CAI modifications that draw air from a high pressure area in the grill?

well_fans

4,193 posts

246 months

Monday 22nd January 2007
quotequote all
I assume you are referring to an over the radiator cold air intake in the first section of your post, this actually has been shown to push far greater volumes of cold air into the engine than the standard airbox. As for the additional holes in a standard box they are drilled in such a location as to take more cold air from the outside and not to take hot air from the engine bay, at least assuming you put the shielding back in place.

kev10-30

83 posts

261 months

Monday 22nd January 2007
quotequote all
There were some after-market "wide mouth" OTR kits supplied by CAPA or SSV which were poorly designed and actually reduced the airflow. Several of the 2004 cars had these fitted as a CAI mod (mine was one). Best advice would be to remove it and return to the standard airbox while adding an extra hole.

Le Sarthe

462 posts

236 months

Monday 22nd January 2007
quotequote all
I have an OTRAI....

Made huge difference to my set up...

uk hsv

1,692 posts

275 months

Monday 22nd January 2007
quotequote all
Le Sarthe said:
I have an OTRAI....

Made huge difference to my set up...


You have a new CAI not one of the poorly designed units mentioned above...thumbup

jimb0

318 posts

251 months

Monday 22nd January 2007
quotequote all
uk hsv said:

You have a new CAI not one of the poorly designed units mentioned above...thumbup


I remember you mentioning these. Are they generally available now? Or still in development?

Le Sarthe

462 posts

236 months

Monday 22nd January 2007
quotequote all
Thought it must be different as it certainly works well yes

Instant difference - Most definately more air getting in as more power generated and better throttle response...

Finished my Wortec NA upgrade very nicely indeed.

Gelf VXR

Original Poster:

713 posts

229 months

Monday 22nd January 2007
quotequote all
Le Sarthe said:
I have an OTRAI....

Made huge difference to my set up...


Do you have a web link for further details or photo's of your installation? Please

ringram

14,701 posts

270 months

Monday 22nd January 2007
quotequote all
Pics Sean (Saw the exhaust at rogers. Looks good)

My otrcai was definitely worth it too. Much better than the stock arraignment's.

Mine is of the Oz PowerTorque style. Basically 1ft of intake to get to the throttle blade.

Gelf VXR

Original Poster:

713 posts

229 months

Wednesday 24th January 2007
quotequote all
jimb0 said:
uk hsv said:

You have a new CAI not one of the poorly designed units mentioned above...thumbup


I remember you mentioning these. Are they generally available now? Or still in development?


Any more feed back on this?

ringram

14,701 posts

270 months

Wednesday 24th January 2007
quotequote all
This is the PT style one I use.


Gelf VXR

Original Poster:

713 posts

229 months

Wednesday 24th January 2007
quotequote all
ringram said:
This is the PT style one I use.




Looks good, have you done away with the AFM? I had in mind ducting past the radiator into the mouth of the lower grill?

Whats happened to WRC technologies, its the only reference to 3rd party induction modifications I can find and the web sites down?

ringram

14,701 posts

270 months

Wednesday 24th January 2007
quotequote all
What AFM!? Yes it was removed about 2 days after I got my car. Mafless is the way to go.
Better throttle response and zero intake restriction.

ringram

14,701 posts

270 months

Wednesday 24th January 2007
quotequote all
Oh also you can get a G&D intake from Oz which fits tightly past the radiator and pics up air from in front of it. You need to mess about a bit. Mine sits over the radiator and pics up from the front of the bonnet. After a drive around if you open the bonnet the intake is cold to touch. While idling it heats up a bit.
I was going to put some reflective heat shield on the underneath. Also why I got it in white.
The K&N filter gets a bit dirty though.

You can check to see if you have an intake restriction by looking at your open throttle manifold pressure. If its less than atmospheric (ie slight vacuum) then you have a restriction. With the Fast90 the restriction was removed in mine and I gained around 4Kpa at WOT. Basically that adds straight to the power output.

Gelf VXR

Original Poster:

713 posts

229 months

Wednesday 24th January 2007
quotequote all
ringram said:
What AFM!? Yes it was removed about 2 days after I got my car. Mafless is the way to go.
Better throttle response and zero intake restriction.


Does removing the AFM require a remap?

Le Sarthe

462 posts

236 months

Wednesday 24th January 2007
quotequote all
Gelf VXR

My OTRAI is a black version not dissimilar to ringrams. Basically after head and cam job we needed more air to optimise the set up and this worked a treat. A Fast90 and bigger TB woudl push it further but may take the fuel use to an unacceptabel level for me with my mileage (it is fine just now)anyway I had decided if I was to go any further with teh power game it would be stroker time......500rwhp no probs!

Yes you will need a custom map for your set up if you go mafless although other options may be available - ask Roger at Monkfish.

Personally I have had veryy few issues with Mafless only on stupidly hot days did it seem to loose a bit of power but so do FI cars. On cold days yippeee!

Oh my idle is great, enough of a lope to sound a bit different from stock but nto too much so that the car windows shake out which is great as it is my daily driver (just booked in for 60k service!).

Runs on cruise, stops an didles fo rages in traffic jams and then on fast cruise - no issue at all.

ringram

14,701 posts

270 months

Wednesday 24th January 2007
quotequote all
Yes, unless you have an HSV GTS (UK GTS-R) in which case its already done.
It will still run, but will run off the low octane timing table. A quick fix is to copy the high to the low. (As per HSV GTS) But there is more to it than that (as expected). Once removed the car will run off the VE table with hundreds of cells instead of the maf table with 60 odd cells. Obviously much better resolution with the VE for better total driving experience, but it really means that the VE table needs to be tuned. From the factory its easier just to throw a maf at it and say you fix the fueling up instead of making the VE table accurate. If you run Speed density, its best to get the whole VE table zero'd in. The VE table is a map of engine efficiency as RPM x MAP. Each modification you make can alter the VE table.

ringram

14,701 posts

270 months

Wednesday 24th January 2007
quotequote all
Le Sarthe said:
A Fast90 and bigger TB woudl push it further but may take the fuel use to an unacceptabel level for me with my mileage (it is fine just now)anyway I had decided if I was to go any further with teh power game it would be stroker time......500rwhp no probs!


At the same speed the better breathing engine should use less fuel (less pumping losses)... unless you plant your foot then the better breathing engine will eat more fuel (and give more power).

Island boy hsv

726 posts

261 months

Wednesday 24th January 2007
quotequote all
I would recommend this style of OTR cold air intake. I ran the VT-VX version on my car for a wile. It allows you to run with or without a maf. These are some preproduction pictures the unit should be avalible soon.

The production one will be avalible in black.





well_fans

4,193 posts

246 months

Wednesday 24th January 2007
quotequote all
ok so who supplies it and what sort of money are we talking about? LSV have one similiar to ringrams in black in stock for a reasonable price which I was considering buying.