I know the general rule of thumb is that whatever the engine makes unboosted, it doubles at 14psi.

I was wondering if I were to boost the output of the motor by adding a mrev2 and a plenum spacer would I see noticeable power gains seeing as the NA guys are seeing huge power gains from those bolt-ons.

I figure if they are making gains NA i would see decent results boosted right?

 

For FI just get the Motordyne 5/16 Spacer.

On my car, it showed gains of just over 40whp the minute I bolted it on and did another dyno pull.

This topic has been gone over several times now including which plenums actually worked with FI as well.

 

what type of motor do you have though. the mrev2 has the biggest power gains on the revup which i have and the space compensated for the loss in upper rpm power.

I understand if you have a non revup how a spacer would show you those types of gains. I just want to know what I might be able to find?

 

not even close, in a perfect world with a perfect turbo mayby but here in the real world we deal with compressors that flow set amounts and generate heat from compressing no educated person will say you will double your NA power at 14 psi(especially since engines are rated at 14.6 psi absolute so 14 psi isnt even double atmospheric pressure. 14 psi from a gt30 turbo is going to be vastly different then 14 psi from a gt40 , pressure is only one part of an equation.

the engine dosnt matter de, hr, or rev up it has nothing to do with the engine its all in the fact the rev up has slightly bigger cams and the mrev is designed to flow more up high.

 

2006 G35 - RevUp

 

i well surpassed doubling my stock na power at 14psi. i'd think that most people can double their na power at 14psi with greddy TT kits or bigger.

most people make around 220-250ish stock, and can easily make 500 at 14psi, probably even with the smallest JWT kit.

 

question is str8 did you make that power because of the turbo, or because of cams revving the engine out higher? simply throwing a turbo kit on isnt going to double the power with everything else being the same which is what the op is hinting at because that would require 14.6 psi at sea level which most places are higher as well as a 100% efficient turbo or turbo/intercooler combo which dosnt exist

 

jerryd87 is correct on the psi not meaning much since there's so many other variables to consider including turbo size and efficiency.

Hell, my BP setup with PP6266 almost doubled my stock whp at 9.75psi on Dynojet.

 

Silly question, but to BS some...

238whp stock

605whp @ 13psi

656whp @ 15.5psi

 

i understand that different turbos have different efficiencies. that isnt my question. I know that a gt40 @10psi will make more power than a gt28 @10psi. I wanted to know if i will see a noticeable difference in power by adding the mrev2 and the spacer or is there a better place to build the motor? I dont really have high hp goals. I just want to leave the boost pressure the same and see gains by not increasing cylinder pressure.

 

again its questionable what cams are you running, its still just another piece of the puzzle rev up mayby slight gains, after market cams likely a decent gain there is no universal answer for anything period on a car

 

Who-ever told you that rule of thumb is a dumb-*** and you shouldn't listen to them anymore.

 

OP,

You haven't given us enough information about your FI setup or power goals to advise you whether it's worth it to add the MREV2 and plenum spacer. Depending on your setup and power goals, they may be completely unnecessary. But you would probably get the same or better gains by just increasing the boost by 1 or 2 PSI. As long as you aren't already pushing the limits of stock block power level or a safe pump gas tune, you should be fine if you increase the boost by only a couple PSI. If your power goals are modest (as you stated) on a capable kit, you might get better bang for your buck by just increasing the boost a tad.

If you are dead set against upping the boost and/or just want to optimize your setup anyway... then focus on intake and exhaust improvements to maximize your power on your FI setup at a given PSI. The cost of adding MREV2 and spacer would certainly be cheaper than installing aftermarket cams.

So help us help you by giving us some info about your setup.

• Which FI kit?
• Stock block or built motor?
• What cams?
• What exhaust setup?
• What EMS and what fuel is it tuned on?
• What are your current whp & PSI numbers?
• What are your whp goals on your setup?

 

any of those spacer or lower plenum kits won't add considerable power without a tune.

The reason people see such huge gains is the fact that the untuned 350z is a dog. Just by getting the stock car tuned you can pull an extra 20-30 hp out of it. Now add some higher air flow and a good tune you have 40hp easy. A lot of people neglect to mention the tuning part of installing those things.

 

You need to double the amount of air in cylinders for doubling the power. Simple as that. Now, will that be with 10, 14 or 20psi fully depends of your setup.

 

Took the words out of my mouth... The tune is going to be very important to allowing any of the parts your mentioning to work to their fullest potential. Just bolting on and going might help a little bit, but until you are tuned for your mods, your depriving yourself of easy additional power.