Is the 5/16th spacer necessary with MREV2 to get the gains as advertised (19+ trq and 15+ hp)? I just ordered the MREV2 today, no spacer. Do I need the spacer too?

No you don't need the spacer.

Good, I was going to be annoyed if I needed the spacer to work as advertised. I have room in the budget for $450, but another $300 would have been pushing it.

Do you have the revup? If so u want the spacer.

Yes I have the REVUP. So I do need the spacer...

You don't NEED it, but if you have the rev up you WANT it.

Ya, I went ahead and ordered the spacer too. If I'm going to do it, I might as well do it right. I wish the website was a little more clear about that. There should be a package deal setup for that option too. So people like me won't make that mistake in the future.

Oh well, you gotta pay to play. I can't wait to receive my new toys. Now the waiting game... tick... tock... tick... tock... Is everyone else as impatient as I am when it comes to waiting for stuff like this...

So for the Revup engine, the MREV2 and 5/16 spacer are best when working together? When combined (as a pair) with a Z-tube and K&N, roughly what gains can be expected?

I have a 05' 6MT and I just installed the 5/16" spacer alone without the mrev. Will the spacer alone do anything for the revup engine?

On the RevUp engine a spacer alone will afford little. The MREV was originally designed with the RevUp engine in mind. The original MREV was composed of the spacer and the non revup engine's lower collector.

So the best combo for a Revup engine now is still a 5/16'' spacer + MREV2 lower plenum?

MREV2 plus 5/16 spacer is the best bang for the buck mod out there for the Rev-up (13-15 hp for $700...OK maybe test pipes are as cheap.....but THEN you have to get engine management...lol). From now on, you will be paying at least 1K for every extra 10 hp you acquire. For example, good exhaust...1.2-5 K=8-9 hp...TT 80-120 hp 10plus K, etc...

That's why my performance mods will stop at Ztube/K&N, 5/16, and MREV2.
If I keep the car longer than 12 months, I might do HFC and exhaust, but that's all... Damn NA power...

Thanks for the answers!

why buy a car and only keep it 12 months?

No kidding, if he bought it new talk about taking a financial loss...