installed single runner intake manifold on my mp5!

[jamesk]

THEMAN- what are you arguing about man? your saying this intake manifold gives you a high end. its understood by everyone in this thread. that is why i bought the fidanza flywheel, to make up for the lost of the low end. but after i installed my manifold, i feel like i didnt loose anything.

the point of me talking was to say that the fidanza flywheel and this manifold is a sick combo, and the car pulls through out the entire rpm range.

but, what your saying about the vics system is true, but its dead technology and pretty much useless. we do not need this vics system. we already have short rod ratio's (gsr motors do not), i think these engines already have a good low end because of that. these motors were design based off torque (for trucks unfortunatly), so idk why mazda put this vics in there in the first place. the problem is the high end, and that is what i am trying to improve.

after i get this afc installed, im going to try to find a dyno, show everyone the chart, and try to figure out what the best thing to do in working on my horsepower rating.

thanks for the help though, i appreciate all the input your trying to give everyone.

 

[TheMAN]

gsrs also have short rod ratios (not as much as the FS but in the big picture it still is)... many factory motors have that because it's easier to make it run clean and produces better low end torque

 

[Ham*Sammich!]

WOW. very informative

 

[Ham*Sammich!]

WOW. very informative thanks for the info guys

 

[LordWorm]

you're right in that OEM dual runner intake systems give a flatter powerband... IMO more useful for the street... far from ideal as far as maximum hp standpoint.... 99% of our cars are street driven, and I really think that this is more practical than to have the more "max power" intake

if you check out the integra GSR's B18C1 intake manifold, it is dual runner... but the B18C5 in the Type-R gets rid of that and have a single runner.... the differences? the GSR has a flatter powerband, whereas the Type-R is more peaky

as I said before, a single runner system can only be designed for a certain rpm range.... in the case of the 626 one, I believe it is more for midrange response... a compromise... the protege's VICS intake is a compromise for a flatter powerband, not designed for something peaky but it does give better top end IMO over the 626 one

oh and the JDM intake cam has the same lift, it just has more duration and provides more overlap

The issue is with NA tuning, you have to compromise. Normally that involves pushing the peak up and sacrificing low end response. broad flat powercurves are a compromise. They work, but they are not the best of both worlds.... you end up with average torque, and average top end power.

Thats all well and good, until you decide to push the envelope, then the standard manifold becomes a massive restriction to making power. An economical stop gap is the 626 manifold - although it is also far from ideal. HOWEVER, the 626 manifold will, given its design, support a higher redline, flow more air and make more power through the midrange, at a cost of torque..

The point is, its a valid upgrade - if you don't mind losing some response, which most NA tuners don't mind sacrificing... you lose some torque, but you make it up with interest in the upper mid range and top end...

 

[TheMAN]

if losing low end and gaining all top end power is what some of you guys want, then go for it... your gas mileage will probably suffer too, something that's important to many people as gas prices are expensive anywhere these days

like I said... 99% of us drive our proteges on the street, I still think a usable flat powerband is more practical (and efficient for gas mileage) than anything for a street motor..... but if max power is what you are looking for, then ditch all the stock s***, A/C, and power steering too you'll be sweating your ass off for a few more hp while I putt around town in the comfort of A/C during summer

since there's those of you who are dead set on getting rid of the VICS intake and using the 626 ones, and those like me who are just happy with what VICS offers, I'm really surprised everyone has quickly forgotten about the japanese/european 626 intake manifolds (which should restore some low end and some power at redline) that I mentioned a while ago in that huge "SU" thread

it's like the 626 s*** we got but it adds a small helmholtz resonator to boost response.... I guess everyone forgot about them because 1) the USDM s*** is easy/cheap to get, 2) no one cares, or 3) everyone are just a flock of sheep who gets what everyone else gets and don't try something different to discover new things

I do think it was cool jamesk got this USDM 626 intake manifold to try though, but I still think there's no findings or discoveries until I see the dynos

 

[MakeMeGoFast]

I take it you like being right?......lol

 

[dwpeek]

Both points are well placed, but in the end we all want numbers. Once again, I live in the Show-Me state. I want to see numbers. PROOF, is what we need to see.

Because both points are valid, I think both doubt and hope have been placed in our minds. That's all I'm saying.

I think JAMESK is right. Taking away from the lowend, he had to make up for it with a lighter flywheel to make it rev faster. I thougt of this concept before hearing about it. I'll bet it runs great. Do you have a car that you have raced prior that you can now beat? I am very interested.

 

[LordWorm]

if losing low end and gaining all top end power is what some of you guys want, then go for it... your gas mileage will probably suffer too, something that's important to many people as gas prices are expensive anywhere these days

like I said... 99% of us drive our proteges on the street, I still think a usable flat powerband is more practical (and efficient for gas mileage) than anything for a street motor..... but if max power is what you are looking for, then ditch all the stock s***, A/C, and power steering too you'll be sweating your ass off for a few more hp while I putt around town in the comfort of A/C during summer

since there's those of you who are dead set on getting rid of the VICS intake and using the 626 ones, and those like me who are just happy with what VICS offers, I'm really surprised everyone has quickly forgotten about the japanese/european 626 intake manifolds (which should restore some low end and some power at redline) that I mentioned a while ago in that huge "SU" thread

it's like the 626 s*** we got but it adds a small helmholtz resonator to boost response.... I guess everyone forgot about them because 1) the USDM s*** is easy/cheap to get, 2) no one cares, or 3) everyone are just a flock of sheep who gets what everyone else gets and don't try something different to discover new things

I do think it was cool jamesk got this USDM 626 intake manifold to try though, but I still think there's no findings or discoveries until I see the dynos

the small "helmholtz" resonator is on the aussie 626 manis as well (just pulled one apart at andrew's place)...

Helmholtz can be used for 1 of 2 things. You can tune helmholtz for power, or tune helmholtz to cancel noise. Obvioulsy if by some insane fluke, the point at which power is improved is the same frequency as the noise cancelling, you get both gains.

But this resonator does nothing for power (it infact, would make it go backwards, because in effect it is increasing plenum volume, which will reduce intake velocities and harm low end more).

The mathematics i've given you are part of the equation for working out a resonance tuned intake manifold. The rest of it is in plennum design, and the ram tunnel - essentially making the ENTIRE MANIFOLD AND INTAKE TRACT a resonator. Thats how you make power. Slapping a 750mL plastic chamber on the side of a manifold wont do diddly squat for power.... you're clutching at straws.

The 626 manifold reduces low end response, yes. But it wont reduce it to the point that its detrimental to drivability of fuel economy. Infact, in the midrange, where 90% of your driving is done on the street, it would be highly effecient because of reduced pumping losses and increased volumetric effeciency. This isn't even taking into account other fuel economy improvements gained by other modifications which are usually done to our cars - header (reduces pumping loss, improves VE), exhaust (reduces pumping loss, improves VE), light weight flywheel (reduces rotating mass, improves fuel economy) and so forth....all modifications which mean the engine needs to work less to achieve the same result and thus saves money at the pump. Add management into the mix and even with the 626 manifold you are going to have probably at least a 50% improvement in fuel economy over stock.

EXTREME tuned manifolds (such as the one i'm designing) will hammer the low end and midrange bad, and your argument will be 100% valid on the manifold i'm designing, but economy isn't the goal with my manifold.

No matter what argument you are going to come up with, the SLIGHT improvements in the breadth of the power curve vs the 626 manifold are not enough to counteract the benefits of going to the 626 manifold. The car should have had single runner from the get go. VICS gets the "EPIC FAIL" award... and if you opened your eyes and looked at the numbers that come out of the flow bench, the results of the mathematic calculations, and so forth, you'll see that it is sub par.....

I'm happy to run through all the calculations and theory with you if you wish... not in this thread though, as it isn't an effective way of having a conversation. Perhaps we could tee up an MSN session at some stage, have a discussion, and i'll copy and paste the results of the conversation into this thread for all to read.... you can ask any questions you need to ask, and i can answer them for you, rather then having this conversation draw out over 20 odd pages (which is how it will go if we keep this up!).

I'm more than happy to discuss with you, pm me if interested.
Ta.

 

[AusOrion]

....looked at the numbers that come out of the flow bench....

The 505 intake manifold in design / testing at the moment will hopefully get put on a flow bench against the stock P5 and 626 intake manifolds. This might give us a better idea of the relative differences...

Cheers.

 

[LordWorm]

The 808 intake manifold in design / testing at the moment will hopefully get put on a flow bench against the stock P5 and 626 intake manifolds. This might give us a better idea of the relative differences...

Cheers.

Still will need to do calculations for air speed at 0"hg though... from the (very little) i've read its being geared for FI applications so whilst it may flow its nuts off, it might be far TOO detrimental to low end response on a normally aspirated engine...

the formula for working out the diameter of a pipe for a desired velocity is

D = SQRT(CID x VE x RPM) / (v x 1130)

where CID is cubic inch displacement (for a runner on a 4 cylinder this will be engine displacement divided by 4), VE is volumetric efficiency, RPM is rpm, V is desired velocity, and 1130 is a constant used for the equation.

you need to move the diameter over to the other side of the equation to calculate velocity if you know Diameter but don't know the velocity...(formula as it stands is for calculating diameter when you know what your desired velocity is...)

a pressure drop calculation would probably also be prudent, both for FI and NA. I don't actually have one handy but googling will help.

using that formula, you can check a handful of RPM's and VE numbers and plot a curve, and get an idea of the velocity of air through the pipe over the rev range... obviously this calculation wont stand up if they are using a tapered runner, but it'd give you a fair idea.

with NA, you want the maximum velocity without compromising flow at your desired peak power RPM.

TheMAN correctly points out, that flow *isn't* everything - it is important, but so is velocity... once you have the flow numbers, you should do some calculations vs the stock and 626 manifolds to determine whether or not air velocities are idea.

incidentally, you can use that calculation to determine the correct throttle body and intake pipe diameter... air entering the plenum should never exceed 180ft/sec at your desired peak power RPM, otherwise the plenum won't do its job properly (the plenum is there to slow air down so you have a mass of cold slow moving air that the runners can feed off of).

 

[dwpeek]

Uh What!

 

[LordWorm]

Uh What!

did i miss something?

 

[dwpeek]

did i miss something?

I was trying to say that I didn't understand any of that equation that you explained in your last.

When that stuff is expllained to me, that is usually my response.

 

[i12drivemyMP5]

Long way to go to get to "Things are purpose built". The purpose of oem USDM s*** is NOT max flow & power. The purpose of the changes discussed here are not avg pwr, avg torque, clean emissions & max mpg. The morale of the story for this motor is...wait for it....wait for it....build it for a single purpose because there is no way to build it that covers every purpose. It's gonna suffer in one respect or another whatever you do...sanely, realistically & cost effectively that is. Pick one way & minimize your compromises, just like the threadstarter has done with the flywheel/626 IM combo. It's street, strip, or track....it cannot be all 3 at the same time, unless you spend 6 figures for it. Thanks for all the science tho. Had on my special glasses so I wasn't blinded by it. Bought them from Thomas Dolby. Go ahead, everybody all together now......WHO???

 

[AusOrion]

Still will need to do calculations for air speed at 0"hg though... from the (very little) i've read its being geared for FI applications so whilst it may flow its nuts off, it might be far TOO detrimental to low end response on a normally aspirated engine...

The current intake manifold is being designed for FI applications. Depending on sales of that one and expressed interest, there may be some scope for development of an NA design custom manifold...

I guess there will have to be some discussion on where exactly the peak flow for the manifold will be set, but I sure it will be done at the appropriate time...

 

[LordWorm]

The current intake manifold is being designed for FI applications. Depending on sales of that one and expressed interest, there may be some scope for development of an NA design custom manifold...

I guess there will have to be some discussion on where exactly the peak flow for the manifold will be set, but I sure it will be done at the appropriate time...

oh i thought you were just looking at getting the turbo manifold and going from there.

i'm not saying it wont work - just saying if you do go down that route, you can get a fair idea of whether it will work before handing over your cash....

 

[dwpeek]

I think it will work as long as you do it the way the guy who started this thread did. (along with the lighter flywheel) If the 626 mani takes away from the lowend then you compensate by making the car rev faster. It only makes sense: when you are lacking in one area, compensate. Right?

 

[LordWorm]

I think it will work as long as you do it the way the guy who started this thread did. (along with the lighter flywheel) If the 626 mani takes away from the lowend then you compensate by making the car rev faster. It only makes sense: when you are lacking in one area, compensate. Right?

right.
so long as you've only lost velocity at one point on the curve...

if the velocity is poor all the way up, it'll be lathargic all the way through the rev range. Hence why its a good idea to plot the projected velocities on a graph first

 

[505zoom]

lol I am having major deja vu reading this thread... was going through all the number crunching about a month ago on this. Good stuff LordWorm.