09-25-11, 09:42 PM
The air filter element is quite small on our N* and the intake tube to the air cleaner box seems small for an engine this size. So I am looking to open it up. The K&N filter that fits into the OEM system is also small, but Volant offers a completely new system. Not sure if it uses a cone filter element (which would be an improvement) and if the tube to the manifold is actually bigger and better than stock. Anyone have any experience with making the intake system breath better? I believe there is some opportunity for improvement here.
Members report modifications to the Volant kit are necessary and performance isn't much better. The jury is out on K&N filters, too. If the airflow really is better, it may not filter as well as an OEM paper filter. Cadillac engineers didn't miss much when designing our cars.
09-25-11, 10:11 PM
I know that the Caddy engineers look at everything, so I question spending anything expecting to get a performance gain. Case in point: I knew the ex mfgrg mgr at a local supplier of Corvette front suspension components. When the Caddy engineers came in to evaluate components for the XLR they saw problems with the Vette design and insisted on changes.
But, that paper element is very small, particularly for a V8. I think I will call Volant and see if they use a larger element in their system. If not, it is probably not a wise investment.
Another point: My company buys John Deere diesel engines fitted for driving fire pumps that we build. These systems are all about performance, reliability, and fault tolerance. They use K&N filters.
09-26-11, 04:06 PM
Volant and Corsa on my 1SG 05 STS4. Sounds cool, does nothing via seat of pants period. MAYBE 5-10 hp on a dyno but its completely unmeasureable to the average person.
09-26-11, 04:34 PM
there's not need to 'open up' the air/intake system on a N* engine ... no need at all...
the paper filter in there will flow just fine (even at WOT)
there is not restriction in these engine's air/intake system
09-26-11, 04:58 PM
I'd have to agree with the waste of money deal.......... Have done nothing to the STS but on a Corvette added lots of bolts ons with nothing noticeable until a set of headers and a custom tune. Unbelievable.
09-26-11, 11:29 PM
Think I'll simply get a new paper filter. Sure seems small and restrictive, but the reports here are unanimous. I (finally) checked previous posts too with similar remarks. BTW, K&N did an impressive study on whether their filiment oil damages the MAF sensor. Their facts disprove any link of course.
09-27-11, 09:38 AM
I haven't dug into it, but I'd wager, like most cars built in the last 30 years, the STS has a CAI, OEM.
High underhood temps mess with emissions, so it's not for power, though it doesn't hurt.
Look underneath for a tube going to the bottom of the air box, then follow it the other direction. Probably comes out behind the bumper, somewhere.
09-27-11, 10:26 AM
since 1993 the transverse mounted N* have had a CAI from the factory ... i would assume 12 years later when they brought out the longitudinally mounted N* that they would continue with a similar design (I'm not 100% sure but i'd probably put money on it)
09-27-11, 01:31 PM
If you pull the drivers side wheel as to look at the brakes,
and the inside wheel cover, you will find the
PCM and the beginning of the CAI.
Have Fun ! Good Luck !