Motordyne spacer's
 

So here's the delema. I'm thinking of getting a motordyne spacer, but I don't know what to get. 5/16" or 1/2"..? So besides the fact that by installing a 1/2" spacer you can't run a strut bar what are the other pros and cons. As far as HP and TQ what's the difference?. BTW my g is a 04 m/t with a stillen z-tube and k&n drop in, on the 04 oem airbox. I also seen the intake runners spacer anyone have good turn out with that?

5/16" will offer better midrange power while the 1/2" will benefit more at higher RPM's.

Well put. Also the debate on throttle body spacers always generates drama. Some swear they work, and some laugh at the thought. Hard to know who to believe, but they are hard to find which tells me they aren't super productive or more companies would promote and sell them. I think Tony at MD dyno tested them and they showed no gains, but I couldn't find the thread to confirm that.

You should be able to have the GT Spec strut bar... but no plenum cover. Though I have 5/16" in my 04 coupe with an MREV2 lower plenum, there is enough in the adjustment to accomodate the extra height.

The difference between the spacers as mentioned above is not that different unless you plan serious NA mods and a tune. If so, go with the 1/2". Tune is good regardless.

Good. I want the mid range power and do plan on a NA build. So I guess I should go with the 1/2" and get a tune. So what's ur guys opinion on the most gains na build ? HFC's, headers, MD spacer, port and polish? What am I missing? Yea I also did some research on the runners spacer I'm gonna skip on that.

Comon man you have been here long enough and are even premier!! This has been covered many times before!

And you state you want midrange power yet say you want the 1/2"??? Most people choose the 5/16" for the more usable power range.

the mods people seem to praise the most for NA builds are the 5/16 spacer and HFC's. those mods give the biggest numbers and are the most noticeable throughout midrange rpm's

Haha I ment 5/16" obviously. I already purchased it. Now I'm looking into the berk HFC's

I tink the 5/16 shows good average gains but I bet the 1/2 will show better gains with a good tune.

"better gains" is a very arbitrary method of judgement. It is very well known that the 1/2" spacer will provide more TOTAL TOP END power, so if you just want maximum power for dyno or if you are always racing around in the very top of your powerband that might be a good option. But 5/16" provides much more usable,mid range power which for 99%+ of people on this forum would be used/noticed more often.

that is also for a "stock" motor

I'm saying that with a TUNE it changes the gains and the powerband. Stock tune then what you are saying is mostly correct - but considering they are not much different in "useable" HP and TQ the high end is worth the trade off.

Pretty sure you are thinking about the tests on HR engines, DE's do show gains afaik.

The TB spacer is a highly debated discussion (Design Chaos) - this is a highly debated discussion. I had one for a long time. I was still on the fence about it.

doh, missed the shift in discussion too the TB spacer...

Where is any type of documentation or even theory on why the tune would cause the 5/16's gains to not be as considerable any longer while the 1/2's would skyrocket? You do realize how a standard tune works right? We aren't talking about a super indepth tune that would take hundreds of hours and many thousands of dollars here, if even then there was a difference then.