I have seen multiple videos of people installing plenum spacers but I’m still hesitant to buy one. I want to buy one for my 06 DE and I heard in a video that it mostly helps in 03 and 04 models but there’s little to no gain on 05 and 06 model Z’s and he provided sheets to prove himself but I was wondering if anyone knew if that was known and is it worth it to buy one for my 06

 

Not worth it. The dollar-per-gain ratio is just too low.

That dollar-to-gain ratio doesn't just include the spacer, it includes a QUALITY spacer and a tune (can't forget about that).

Welcome to the forum, btw.

 

Appreciate it I just didn’t want to go and spend 200 or less to gain a small amount, and thanks this forum is helpful so far^

 

Just remember that an opinion given is always subjective and should never be the final say. That being said I will say that some swear by the spacer, most commonly the ones manufactured by Motordyne or Z1. I know in the '03 to '05 models the shape of the upper plenum tapered down over the front two cylinders effectively cutting off airflow just slightly. The spacer worked to allow more air to reach those cylinders (and the others as a result). I can't remember if the plenum was changed in anyway for '06, but I am sure others will chime in.

I have friends who have placed the spacers on their Z ('04 and '05). Both said the powerband did feel smoother, but only one said it was worth the money to him. If you have the money then go for it. A little extra airflow is never a bad thing. I'd recommend the 5/16" if you do since anything larger will require removing or altering (spacers) the strut bar to clear the plenum with the spacer installed.

Just remember to search. You have 16 years of information at your fingertips. Pretty much anything you need to know can be found on this site.

 

Before today I didn’t even know they were tapered but on my 06 it seems like it has the same plenum? I’m not 100% sure, but yeah I was looking into the MD spacer because it looked like the most praised upon and most trust worthy. I am looking around the forums, honestly great community and great discussions.

 

If you have the 06 rev up, you'll need to get the mrev2 lower plenum it you're getting an upper plenum spacer.

More info about plenum spacers here from motordyne's website: https://motordyneengineering.com/vq35-de/

 

If you have a 2006 DE (and not a 2006 Rev-up) than the spacer 'should' help. The Rev-Up engine has a different lower manifold than the DE that takes advantage of the higher red-line but sacrificed torque. If you have a rev-up engine with the rev-up lower manifold than putting a DE lower (or the motordyne's MREV2 lower) and the spacer AND a tune you will get torque back and you should see 'some' hp gains compared to an OEM rev-up engine - but dont expect more than 15hp gain ... the OEM manifolds are pretty efficient.

Doubled check which engine you have and which lower plenum you have before you purchase. Upload some pictures of your engine bay / front engine / timing chain case and we can help. You will likely have to take off the upper plenum to see the inside of the lower plenum (for pictures) if you want us to help determine which lower you have.