Review: Motordyne M370 Manifold w/ Comparisons

Motordyne

Longer runners, but the only thing that really makes it better than the stock manifold is the dyno results.

NYBladeZ

OP, 5th gear is 1:1 for the m6. I don't know guys, I'm still not sold. In the OP's case you're looking at the cost of the part, the install, and the retune. I'd estimated you're looking at anywhere between $800-$1000 and you're actually losing a few ponies. Granted the loss is up top but it still seems like a a lot for ~12lbs/tq in a limited window of the powerband...

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2009 Carbon Fiber/Red 370z aka Trish: Sports Package, Meisterschaft full catback, Fast Intentions Longtube Headers, Injen Long Tube Intakes, UpRev Tune: Sold
2008 Lotus Exige S Club Racer aka Bella, always leaves me smiling

TypeOne

^^^
I'm kinda with you on this one... seems like for something an intake manifold to be worth that much you should gain significant power throughout the entire band. For that price you shouldn't lose anything, anywhere.


I'm not bashing Motordyne at all, I tip my hat to this, it's really interesting that it works like it does, but you'd think it would be a little more significant for the price.

Has anyone cut open the stock intake manifold? I'm sure there has to be some room for improvement over the VQ37 one... instead of reverting back.

Staples

5th gear loses power on the dyno, so no 4th gear is closer 1:1

Automatic guys run 5th gear in DS mode which is 1:1.

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'08 Infiniti G37s - Forced Induction Fed

NYBladeZ

I still think you're wrong, I did my first dyno run in 4th and it was the lowest reading. All subsequent runs were done in 5th, the only thing that people would want to look out for is to keep from having power cut once the car hits 155mph on the dyno, other then that, 5th gear is a 1:1 ratio.

Gear Ratios (Manual)
1st 3.794
2nd 2.324
3rd 1.624
4th 1.271
5th 1.000
6th 0.794
Reverse 3.446
Final Drive 3.692

You should have to worry about hitting the limiter unless they failed to remove it during the UPRev tune.

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2009 Carbon Fiber/Red 370z aka Trish: Sports Package, Meisterschaft full catback, Fast Intentions Longtube Headers, Injen Long Tube Intakes, UpRev Tune: Sold
2008 Lotus Exige S Club Racer aka Bella, always leaves me smiling

daisuke149

He has a g37. maybe its diff in that car.

Staples

No, you're right IT IS 1:1 in 5th gear. What I should have said was, I made more power in 4th gear then 5th. For some reason, every dyno I have been to I made 15-20 more whp in 4th gear then 5th.

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'08 Infiniti G37s - Forced Induction Fed

Motordyne

You're right about hitting the speed limiter in 5th.

Now that I'm dong the analysis, I noticed what looks like a slight RPM calibration issue on the dyno. The car is run to redline but the plots show only 7300~7400 RPM.

...fairly typical dynajet RPM calibration behavior. Maybe the tire size wasn't entered in exactly correct?
The pre/post results are measured the same way so its all good.

Endgame

I think this is a mod for some, but not for all depending on what your driving style is. If you want to fattened up your mid-range, this is the mod for you. If you plan on spending your life at the red line, maybe this is not the mod for you.

Many of the track/autoX guys may want more of that midrange power as that is where they spend their life more so on the track.

TypeOne

Who doesn't want more mid range?

Why can't it make power everywhere...?



I would like to have my cake and eat it too...

Endgame

You greedy bastard!!

Motordyne

This is actually not the case. See the plot below. This is Staples dyno plot with indicators placed at the redline shifting gear RPM ranges. 6MT for all gears driven to their theoretical speed limit.

The car is faster on the street, 1/4 mile track and the road course with the M370. No matter how the car is driven or how it is shifted.

If we assume this plot is representative of performance and analyze a worst case scenario where it is shifted exactly at redline every time, the average power in each gear is higher.



What this plot shows is the usable RPM range of each gear assuming a shift at redline. When racing, it is not possible to keep the engine at redline all the time. Shifting is required to accommodate the up & down changing of speed. Speeding up and slowing down. RPM continuously sweeps through all the gears.

If you look at the area under the curve of each gear, there is clearly more area under the M370 curves. If shifting occurs at anything less than redline, the delta gain of the M370 increases even more.

On the Street:
Redline shifting doesn't happen all that often but in any case the increased torque is nice to have for daily driving. Higher power is unavoidable in this case too.

On the Drag Strip:
In the case of 1/4 mile racing its easy to see the delta results above. The last stretch of the race is with 9 more HP with the M370. Plus all the added area under the curve of gears 1 through 3.

On the Road Course:
In the case of road course racing we need to consider that the two most used gears are 3rd and 4th gear with a greater bias towards 4th. 2nd and 5th are also used but much less so.

Basically the last 2/3rd's of 3rd gear are the majority of 3rd gear use.
The first 2/3rd's of 4th gear is used most heavily in road course racing. All of the bottom. All of the midrange and much of the top of 4th. (If shifting occurs at anything less than redline the delta gain with M370 only increases.)
5th gear gets used too but it doesn't get used until the velocity is very high @ 123+MPH. And that is assuming perfect shifting at redline every time. 5th gets used but most of the course time is spent in the curves ...where 3rd and 4th dominate.

A typical time weighted average road course race velocity is about 60 MPH - 110 MPH so we can roughly bound the gears and RPM's used within that velocity range.

So it comes down to this. Acceleration rates are determined by area under the curve of each gear. (Not by peak numbers.)
No matter how the 370Z is driven or how it is shifted, it is faster with M370.



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christian370z

I hope someone makes a lower intake manifold that has been ported since my understanding is that is a big limiting factor in the intake system on the VQ37 engine.

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-320whp / 259wftlbs-
SP Rays -- RE-11s -- SpecialtyZ Tune -- Swift Springs -- Stillen 25R Oil Cooler -- Stillen G3 Intakes -- Berk HFCs -- F.I. 12" CBE -- Stillen Sway Bars -- Es14 Spring -- INGS+1 lip -- CF Spoiler -- GTR Start Button -- VLED Parking Lights -- PWJDM V2 shift knob

Megan370z

from what I did during my DIY on the 350hr intake swap is that the lower intake manifold on the 37vhr is quite smooth to begin with and porting it wouldnt give a big difference.

im not an expert but where did you heard about this ?

Motordyne

Hi Guys,

I'm looking for some information on the gearing that will help me do some more detailed analysis on the power curves.

Assuming you shift at redline in a 1/4 mile race what is the entry RPM of each gear as you shift through all the gears?

Example:
When you are in 1st gear and punch it all the way to redline and then shift into 2nd gear, what is the new RPM as you enter into 2nd gear?
What is the entry RPM for each successive gear assuming a shift at redline each time?

Is there a table posted in this forum?

Thank you,
Tony