check out my thread about the 1/4" spacer install help.

https://my350z.com/forum/intake-exhaust/120574-motordyne-plenum-spacer-install-help-and-review-read-this-if-you-need-help.html

Harv

 

In regards to the yellow Z gaining 15 HP, it goes to show how important it is to do all the runs at the same engine temperature. I don't think we got that on that dyno day (I was the 2nd one on the dyno).

I know that Church Automotive will do every run at the same temperature. That's what we did when we compared a 1/4" spacer + stock plenum vs. Crawford V5 in one of my previous post. We ran the car with the same tank of gas, same coolant temp, same dyno operator. We didn't even take the car off the dyno, the install was done while it was still hooked up.

Anyway, with that comparison, I got pretty close to the same results that you did.

Edit: we also did ECU resets with my runs at Church with both setups, and it didn't make any difference on my car. Maybe because the ECU was already running in the most aggressive mode.

 

I actually saw it already. I'm gonna use it to install my spacer. Thanks.

 

after a 2hours rest is not the same

I gained 5rwhp by resting my car 15 minutes

 

that's another very good question ravi, and i don't know enough to give you an answer. that's why i posted everything, to try to get some answers from someone who knows. i would like the other guy who dyno'd two times with a rest in btwn to post his dynos on this thread, too, to add more info. specifically, i want to see if he got so much more "under the curve" improvement like i did, or if it was just up top.
i've read about that...the ecu supposedly allowing more power after each wot, but my previous pulls were done on a dynojet, too, and i am a wot junkie. i can't tell you how embarrasing it was to get lower numbers than guys with just a poopcharger on 3/26.
ps: another thing i don't understand is people say in order to get good dyno numbers, the oil temp, etc, has to be up. well, my temp was certainly up when i pulled with the crawford cuz i had just recently arrived after driving 1.5 hrs from san diego

 

well there you go. if you eliminated all the variables i didn't and STILL got the same kind of improvement, that's pretty compelling evidence to support the claim that the shape of the stock plenum is NOT a poor design that starves the engine, and is NOT just to accomodate the strut bar, that there was a performance reason the nissan engineers designed it that way. imo.

 

Here was my graph from the Church automotive dynapack. I plotted 3 runs with each setup.




Again, the dynapack reads higher. At powertrain dynamics' dynojet on 3/26 with you guys, I got 248 SAE and 259 uncorrected, running the Crawford V5 and 1/4" spacer at the same time (5AT G35 coupe).

 

The reason why after each run you yield more power is not b/c the ECU is changing, it is becuase of the oil temp. For these cars to see its best numbers it takes a few runs before the oil gets to the right temp. If you keep making runs without a rest the numbers will start to drop.

 

amazing. there it is again...area under the curve. and crawford claims they originally designed a spacer, and it didn't make any gains...i'm callin bs.

 

so they made 15whp on a yellow 35th ann?that pretty impressive but hasent nissan revised the new 300hp engine plenum?so even whit that revised plenum they shoed 15whp?mmm hard to beleive

 

i don't believe the yellow 05 was the 35th anniv edition.

 

Next time someone does a comparison dyno, could they do it A, then B, then A again?
This would make it a bit easier to see if the comparison is valid.

 

I just installed my motordyne 1/4" spacer and jwt popcharger. Sounds great! So much more beautiful tunes coming from the engine. When installing the jwt popcharger, I noticed it didn't line up all that well, nor did the heat shield. Also, didn't seem like any oil was on the filter, so my friend sprayed some more k&n oil on it. so now it's rainbow blue and red.

 

cool, turtle. don't go too heavy on the oil. less is best. ya, the popcharger sound is great.

 

matt I think I told you this, but I honestly think your gains were from the cool down period.. You gained 5whp with the spacer swap and 2 hours of cooling, and sheldon/FLZ_boy gained 15whp just from cooling!!!

you should have kept ur kinetix plenum But I'm glad you didn't I just love how it always stays so nice and cool!!!!!!!

 

and it sounds good, too. for me, the spacer is best overall cuz it doesn't rub on my hoodie like both the other two did.
ps: do you know how long sheldon waited btwn the first and second set of runs? 4 HOURS!!! first set around 1045, second set 1445.

 

I just installed the spacer as well and I was wondering if it was necessary to reset the ECU. The CEL didn't come on after my install so I didn't bother reseting it.
On a side note: Currently I only had the pop charger before this and after driving it and noticing what little bit of HP that I got, I'm definately hooked. I think all other mods will have to take a back seat now and just do perf mods.

 

oh shzit, you've got it too, the dreaded mod bug. welcome to the club!
ps: don't need to reset ecu.

 

ry, don't you think if the crawfrd plenum was superior to the spacer, it would have still come out ahead or at least had the same numbers as the spacer did after a rest period? Or to put it another way, if the spacer was inferior to the plenum, wouldn't it have performed more poorly than it did, even with the rest period?

 

Cool thanks.
The bad thing is that I'm getting married in less than two months. So basically all MODS have to stop for now. I wasn't even suppose to get the spacer but I couldn't pass up the GB