I have searched many posts and read manufacturer's website on the PLENUM SPACER. But have a few un-answer questions and/or want YOUR opinion:


"This stealth modification adds 11HP-13HP and is the simplest to install. The 5/16" plenum spacer is fully compatible with all stock and aftermarket strut bars. The engine cover easily fits and never needs to be cut. With the engine cover and strut bar in place the engine bay looks completely stock."
-http://www.motordyneengineering.com/g35.asp

1) I'm interested in the 5/16 due to still getting a significant HP increase AND still getting to use engine cover.
MY MAIN CONCERN IS WITH WARRANTY/DEALERSHIP. WITH THIS "STEALTH" UPGRADE CAN THE DEALER EASILY NOTICE IT? Has anyone had an issue with these and the dealer? For those who have it, is it REALLY stealth?

2) It seems that "11HP-13HP" is a realistic average based on other posts, those that have it would agree?

3) Is 11HP-13HP a notable difference when driving daily?

4) Is gas mileage directly affected by this upgrade? Good/Bad if any?

5) Easy to install w/ standards tools that I may have?


Thanks for your guys help.

 

1. Depends what you're going in for.. if its an oil change + basic X,XXX milage maintenance.. then NOPE.. but if you're going in for warranty work due to engine vibrations or something then yep.. its stealth to service writers, service managers etc.. but the techs that work on the car will notice as soon as he takes off the engine cover. BUT most of them wont care.. but other then that yep its completely stealth unless you're looking for it

2. you may dyno differently from the sheets on motordyne's website due to: 1. different weather condition 2. different car 3. different dyno 4. rim/tire size, etc.. to get a better understanding of how much you'll gain search in the Mod & tech section for dynos.. theres plenty and the mod has proven itself over and over again to be the best bang for the buck$. Since you're getting the spacer.. I'd also suggest looking into their ISO thermal kit

4. Gas milage is uneffected.. BUT you may feel the need to accelerate more at WOT once you get this MOD

5. you'll need:
- Any type of pilars (perfer needle)
- Flat head screw driver
- Standard screw driver
- 10mm socket w/rachet (prefer 3/8)
- torque wrench with the ability to torque 10ft lb
- Some motor oil or WD-40
- Scissors if your installing the CCV valve (ISO KIT)
- A set of hex tools for installing the copper throttle body plate (ISO KIT)
- i'd add speed handle to make things go faster or a long extension

 

Better off using an in/lb torque wrench.....

 

Anybody dyno their G35 before and after the install to see true HP/Torque gains?

Which is the best size for the 2004MY?