What are the actual benefits (and detrimental effects) gained/lost from installing an Induction kit and a Dump Valve?

I've heard that the Induction is a loud system, true?

Also as the engine area does tend to get and remain fairly hot, does the induction kit actually help all that much?

Does the Dump Valve help to alleviate Turbo Lag?

Oh, if it helps, the car's a 99T reg, standard UK edition with no modifications.

Zak

hi zak this i woul dlike to know myself, same car same mods :) if you find out post it back on :)

Zak,

from my personnal experience I would say that an induction kit is beneficial.

My car used to run out of steam at about 5000rpm, once I had changed to the HKS kit it pulls all the way to the red line.

Zak.

Crudely speaking, an induction kit helps your car breathe better by removing restrictions in the air intake path. You'll also hear your existing dump valve as you're removing a shedload of plastic that tries to deaden the sound...

A replacement dump value does nothing unless your current one as failed. If you have to replace it, use a recirculating design one otherwise you could experience troubles with overfuelling...

Quick little story for ya!

Had my UK 96 tested with Magnex full sys incl DP, with a dump valve (Forge atmos) and K&N panel. Came out at 232 bhp.

I liked the noise of the DV but it was drinking the fuel and once or twice cut out at idle.

Took the DV off and put the original back on.... and replaced the panel with an induction kit. 260 bhp :eek:

I didn't feel the DV gave any benefit really, but the filter is definately worth the money! It sounds similar to a DV but not as scary to the public and you get used to it!

MB

Unless you want your car to overfuel and pop and bang with a hot exhaust Nick :D :D On my MY00 UK car I have run various filter / induction systems: standard filter, standard filter with no inner wing piping (resonator), K&N panel, full HKS and (currently) Scoobysport ITG panel filter.

Of all of them, I would say that the HKS produces the most notable improvement - certainly much louder and the car does pull more strongly at the top of the rev range. There have been reports of people suffering MAF failures using these types of filters - but I think this has as much to do with the quality of the fitting as the actual induction kit itself (that said, I ran mine for 6 months with no side effects whatsoever).

As regards dump valves - these are a very personal thing. I have run a Bailey DV (vent-to-atmos) with my full Scoobysport exhaust system - it sounded great and would overfuel causing the exhaust to pop and bang :D :D. If you still have the cats in your exhaust, then I'm not sure this would be such a good idea.

On the downside, I know that Pete Croney at Scoobysport tends to advise against vent-to-atmos DVs because the sudden drop in pressure caused by dumping the air out of the system is not good for the blades of the turbo(I'm sure Pete can give you a more technical description). The other thing I found was that the car developed a hesitation around 3000 RPM - this was very annoying and I also felt the car wasn't pulling as hard either (this was confirmed by a neighbour who also has an MY99 UK Scoob after a drive in mine).

So now I run a full SS exhaust with an ITG panel filter and the standard recirculating DV and the car runs very sweet and pulls like a train (especially on cold mornings, like today :D :D)

In terms of tuning, the biggest improvement you can make to the car (other than serious chipping or major internal engine mods) is to sort out the exhaust. A full decat system will make a huge difference. By all means fit an induction kit, just don't expect massive improvements.

Cheers
Chris

Cheers Chris, and everyone else too!

Had a little change of heart actually. I'm ditching the MY99 UK standard (!) Turbo and going for an STi V!

Zak