so me and my friend both have 2005 g35 6mt. He had ordered the 1/2 basic plenum Spacer(not iso thermal). it came with all the parts including an iso thermal gasket that we DID NOT instal due to not ordering the iso thermal kit. we instaled the spacer everything ran great no leaks no problems and reset the throttle body. we then we out and tested it mine vs his and I beat him every time. both have stock motors and his only has 1/2 in. plenum. Anyone else have this type of problem of power loss as well? do we need to instal gasket to get the full 13 HP? what do you thinks wrong?

 

how does any of your scenario indicate power loss???

First of all, you didn't indicate anything about how the two cars matched up prior to the spacer install (did you beat him three times then too?)...

But more importantly the only way to know if you lost power is to do back to back dynos... racing a guy and beating him doesn't mean his car lost power.

And finally... any breather mods that actually DO lose power are more than likely working - the power loss is because of lean condition which makes the ECU pull timing... correctable by A/F adjustment.

Basically your evaluation is pointless and really doesn't determine anything so there isn't a "fix".

 

https://g35driver.com/forums/intake-...ml#post5076122

 

Plus 6MT = inconsistent based on driver.

 

....^....100% Correct! Two different cars and drivers, what's the point? Maybe he can't drive for **** or your reaction time is way quicker, who knows? Only correct way was like OCG35 posted, a before/after dyno runs with the same car under like conditions. Any air volume distribution increase in our plenums won't hurt performance other wise we wouldn't be using the spacers.
Gary

 

You guys do note he's adding a 1/2" spacer on a Rev up motor right?

 

This is coming from Tony himself.

 

I didnt even pay attention to the fact that it was RevUp...


Still - the method of testing was/is futile... he wasnt representing gains, he was determining loss ... and that cant be done properly by means that he used... I dont recall seeing that 1/2" spacer actually lost power on dyno...

 

Even if you ignore all the valid reasons posted above, the 1/2" does cause a loss of power on the low end but makes up for it on the top end. It's very conceivable you'd beat him under certain circumstances. In the end, there are far too many unknowns.

BTW, you should install the Aramid gasket if you got it. It helps keep the plenum isolated from the engine heat.