pfregeolle

iTrader: (15)

I still think you'd run into velocity issues, as that part mates up to the lower runs which are roughly the same diameter and have a flow to them. The lower runners feed directly into the heads, so I don't think you want to chance messing with turbulence of airflow directly before the heads unless you've really done some research. Seems like you're just messing around just to find out what will happen when you do A, B, or C. I'd say try it, if you don't mind tossing the whole lower plenum away after a dyno session which proves you may have lost power. Just my thoughts.

I'd say just do what everyone else has proven to work, which is lower the two front runners on the lower plenum, and then maybe go so far as port matching the lower plenum to the runners so you get a nice even flow between the two and the gasket in between them.

In the runners on my lower plenum, I just remove the casting marks throughout and polished them up a bit. I'll link photos of mine back in this post in a second.

jellofuel

I'm not sure if a 3 year old thread counts as resurrecting a dead thread, so feel free to delete this post if it's against the rules.

I have a cammed DE, and was disappointed with the power dropping off so sharp after 6200 rpm. To resolve, I added a velocity stack to intake, then swapped in the revup lower plenum. I have the Z1 angled plenum spacer, but my research shows the spacer doesn't do anything on the revup LP, since the issue the plenum spacer addresses was resolved with the revup LP.

My thinking is if I grind down all six runners (and not the front 2 like on non-revup), would this result in any meaningful gains? Is this something anyone's attempted?

Note: I'm happy with the revup LP, and am convinced this is the way to go since the mid-range torque loss is hardly noticeable, and the high-rpm acceleration is a lot of fun.

Tran251

ZZZ-033

Are you still on this forum @jellofuel ? Did you do this work to your engine in the end? Did it make much of a difference?

jellofuel

Yep, I'm active! It took a while to sort out intake and exhaust leaks, as I kept switching parts up, lol. My z spun Z1's rollers to 310 whp, and 272 wtq. The retune was for revup lower plenum with 3/8" plenum spacer, and I replaced the ART pipes and Motordyne resonated XYZ with Z1 test pipes, and Z1 y-pipe. Here's the video;

ZZZ-033

Holy hell that sounds glorious. I was reading about the Motordyne pipes, they seem really good. Why did you switch them for Z1 test pipes instead?

jellofuel

Thanks! A friend showed me this link here. It turns out that you make more power with test pipes when you're running aftermarket headers. I was also able to sell the art pipes for 450, so this ended up being a near zero-cost retune.

https://my350z.com/forum/intake-exha...l#post10217266