New SBR Intake Manifold....How well does it perform?

[Elvenhome21]

I wasn't trying to say that it IS the best, just from a physics stand point it should be better but there is 2 different concepts being followed, the tapered intake should be better then the non tapered when the engine is in a boost state. Because it should in theory make the #1 cyl runner seem shorter and be a closer total length to #4 cyl, even though its not. Its a cc thing, If its crucial for exhaust runners to be the same length, in theory so should the intake. Also another example is the fuel log with pressure drop.

You must be logged in to view this image or video.

IN theory if you reduced the diameter of the fuel log after each injector, #1 injector will have the same pressure as #4

 

[Street Surgeon]

90mm... it's a bigun'!

For accuracy's sake it tapers down to about 80mm at the bore. As for the taper there are quite a few manifolds that are tapered. Just because mitsu didn't incorporate it into their stock designs means nothing. You're talking about the manufacturer that incorporated balance shafts and several other "less than performance oriented" designs into many of their products.

You must be logged in to view this image or video.

 

[Slow99x]

I wasn't trying to argue the point. I was actually asking why this is the only design for DSMs and Evos that use it. I know a few Ebay ones that are cast like the Supra or Skyline one in the post above but why are all others not taperd? I don't think Mitsu or any other manufacturer would want one of the cylinders to run lean. I'm not sure about the theory because the vehicle takes air 1 cylinder at a time and not all 4. It would be cool to see a cutaway of the different manifold styles or at least a computer model to see what really happens.

 

[Elvenhome21]

I wasn't trying to argue the point. I was actually asking why this is the only design for DSMs and Evos that use it. I know a few Ebay ones that are cast like the Supra or Skyline one in the post above but why are all others not taperd? I don't think Mitsu or any other manufacturer would want one of the cylinders to run lean. I'm not sure about the theory because the vehicle takes air 1 cylinder at a time and not all 4. It would be cool to see a cutaway of the different manifold styles or at least a computer model to see what really happens.

the engine does takes air 1 cylinder at a time and not all 4, is true but if you want a smooth running engine you want the pulses to be equalized for lack of a better word, you don't want an engine drawing air in from intake ports that are right next to each other if at all possible, a way to describe it better is with a N/T exhaust manifold a true race designed one.

If the firing order is 1-3-4-2, and you run a tri-y exhaust cyl 1 and 4 and hooked together and 3 and 2 and hooked together. It allows the exhaust more time to breathe out as much of that cylinders exhaust before the other linked cylinder exhausts. Versus if you had 1 and 3 hooked together it would create a lot more backpressure and also make the engine run rougher and zap HP.

This is why more cylinders generally can make better horsepower in the same CI, they are smoother. But a lot of times the added recipricating weight and just engine weight is the downfall.

 

[Slow99x]

I understand that you are applying the inverse of this exhaust pulse to an intake but you must remember that it is pressurized. Granted, it isn't pressurized all the time but it is pressurized none the less. Your theory is interesting and you may be right but I would like to see a working model of these different SMIM designs before I am convinced that a taper design has any effect possitive or negative on a boosted application.

 

[definitiveno]

Ours aren't tapered in general due to space restraints, that requires you to shoot off the plenium which is directly over the cylinders, and there is already enough trouble hooking your radius upper intercooler pipe without getting a smaller battery or relocating it to the trunk.

 

[Elvenhome21]

As far as when its pressurized I don't know how differently it acts but the fuel log was as close to the pressure side as I could get, but until they are dyno tested. Its whatever Intake is best in your mind and price range.

 

[Slow99x]

There should be a right and wrong answer but I don't think we are going to be able to see it without very complicated testing equipment. As far as the tapered and cast design, there is a SMIM I found on Ebay from Japan for early Evos that gets around the battery and is cast and tapered. Looks alot like the Trust surge tank for the Supra and Skyline. I still wouldn't buy from a company I didn't know.

 

[definitiveno]

There should be a right and wrong answer but I don't think we are going to be able to see it without very complicated testing equipment. As far as the tapered and cast design, there is a SMIM I found on Ebay from Japan for early Evos that gets around the battery and is cast and tapered. Looks alot like the Trust surge tank for the Supra and Skyline. I still wouldn't buy from a company I didn't know.

Do you have a picture? The plenium is either A. off center of the intake ports or B. very small possibly C. a little bit of both.

 

[Street Surgeon]

The picture I posted was of the tapered / cast "Veilside" intake manifold for the Supra. This piece is about $2600 bucks and comes with the throttlebody and fuel rail. Not just some ebay cheapo!

 

[Slow99x]

Here you go

 

[Street Surgeon]

Uh, yes I know that there are ebay intake manifolds available, but as I mentioned previously, this is a 2600+ buck intake manifold (with tapered design) that has HUGE gains, also the Greddy SR20DET manifold is tapered as well.

RB20/25 DET IM:

You must be logged in to view this image or video.

SR20DET IM:

You must be logged in to view this image or video.

JM Fabrications SMIM:

You must be logged in to view this image or video.

 

[GVR4592]

I understand that you are applying the inverse of this exhaust pulse to an intake but you must remember that it is pressurized. Granted, it isn't pressurized all the time but it is pressurized none the less. Your theory is interesting and you may be right but I would like to see a working model of these different SMIM designs before I am convinced that a taper design has any effect possitive or negative on a boosted application.

http://amsperformance.com/pdfs/intakemani.pdf

I haven't read this in a while, but I think they tested a couple different runner designs.

 

[Slow99x]

Oh I know. The Ebay manifold is only cast at the top unlike the Trust manifold is 1 complete unit. The runners are also so short you may have no low to midrange power at all. Its funny that Trust made an SR20DET manifold and not a 4G63. To get an SR20 to spin above 7000 you need all kinds of other parts like rocker arm stoppers. I don't know why Japan is so in love with that motor where ours is clearly the supirior of the 2litres. Then there is the EJ20 junk...

 

[ChvyKc]

I don't know why Japan is so in love with that motor where ours is clearly the supirior of the 2litres. Then there is the EJ20 junk...

I completely agree with that statement. I definately do not see the hype either. It's like all those guys that go crazy about the 1JZ motor in the MKIII supras when the 7MGTE is a very capable motor. I guess it's just a matter of opinion.

I still would like to see how these manifold match up. To bad SBR can't do another test like they did for the turbos a couple of months ago. I am sure that other companies would supply a test manifold to see how they stack up.

 

[definitiveno]

Because it's a better initial attempt at a "sports car". Turbo charge, rwd, lsd, hicus........it all adds up at first, but pound for pound we know which car is better (see autocross, drag and rally history for references).

Point is there very into rwd, and with the drift craze, sylvia is the logical choice for them.

 

[definitiveno]

http://amsperformance.com/pdfs/intakemani.pdf

I haven't read this in a while, but I think they tested a couple different runner designs.

As for tapers GVR we weren't talking about runners but the throat of the plenium where the throttle body connects.

 

[Street Surgeon]

Oh I know. The Ebay manifold is only cast at the top unlike the Trust manifold is 1 complete unit. The runners are also so short you may have no low to midrange power at all. Its funny that Trust made an SR20DET manifold and not a 4G63. To get an SR20 to spin above 7000 you need all kinds of other parts like rocker arm stoppers. I don't know why Japan is so in love with that motor where ours is clearly the supirior of the 2litres. Then there is the EJ20 junk...

My brother ran his up to 8400ish all day long. To do so all he bought was a set of 70 buck Tomei rocker arm stoppers. Don't believe all the hype (or in this case negative hype) SR's are very competent motors. In stock form they can handle right up in the upper 500s hp wise, and my brothers car ran a 13 flat with in intake filter, fmic, 3" turboback, drag radials and boost controller. Not bad for just a set of boltons and no tuning whatsoever on the stock T25!

 

[definitiveno]

My brother ran his up to 8400ish all day long. To do so all he bought was a set of 70 buck Tomei rocker arm stoppers. Don't believe all the hype (or in this case negative hype) SR's are very competent motors. In stock form they can handle right up in the upper 500s hp wise, and my brothers car ran a 13 flat with in intake filter, fmic, 3" turboback, drag radials and boost controller. Not bad for just a set of boltons and no tuning whatsoever on the stock T25!

An online buddy ran a 12.2 with bolt on's and t25, his car was setup very similar to your brothers too. He was ###### on race gas though....very quick.

 

[Slow99x]

Never met a Nissan that I couldn't walk all over in every sense. Straight line, top end, corners. My friend even has a Skyline GT-S and he is terrified of my car. I know they are out there but I haven't met anyand I've ran accross quite a few.

 

[Boosted98gsx]

Allow me to show you what the worlds fastest 4g63 runs:

You must be logged in to view this image or video.

Yes, that is an old buschur intake manifold.

For large quantities of airflow, a non-tapered plenum is the best way to go. In a pressurized system, air is going to the path of least resistance reguardless. Putting a taper on a plenum is just putting something in the way. Same goes for raised velocity stacks. The ones in the magnus, being as tall as they are, will do nothing but create turblance in the air as it tries to reach the runners further away.

From an engineers perspective, a uniform plenum, with parabolic, non-raised velocity stacks (where the top of them does not raise from the base of the plenum) is ideal for maximum airflow.

 

[definitiveno]

Never met a Nissan that I couldn't walk all over in every sense. Straight line, top end, corners. My friend even has a Skyline GT-S and he is terrified of my car. I know they are out there but I haven't met anyand I've ran accross quite a few.

Are you in japan?

 

[Syndicate]

I think people will post what they think is good depending on the design of their aftermarket manifold , brent rau does use one that is not tapered . he also has 1000+ whp heh.

Unless someone actually does benchmarks and full flow tests we wont know for sure who has the better manifold ( for the price )

Im not ever going to go past 600 horse power so whatever manifold I have is what works for me because its where i spent my money. Id be more concerned about the strength of the welds then I would be about the intake manifold being tapered or not . the magnus and ams both have velocity stacks . Ive never seen the inside of the old BR mani so i dunno ( alough since its cast im guessing no? )


I think its pointless to bicker since none of us have enough knowledge todo so .


My mom also put gummy bears in my lunch today so I am fairly happy , their ears are somewhat tapered.

 

[Elvenhome21]

I think its pointless to bicker since none of us have enough knowledge todo so .

We aren't bickering, we are just bench racing without a dyno

 

[Syndicate]

aahahahahaha , ya I hear ya . I really wish someone had answers .. always seems its up to people that get creative and the mindset to look into things and get us real answers .

Alough most of us are just lemmings trying to follow what others have done , because we dont want to waste the money on a "chance" .


People seem to forget you could make a intake manifold out of wood that would perform decent . I can picture a hallowed out trunk and some think hallowed branches as runners .
I think a black cherry stain finish would be nice personally.

With that said , even though I have limited knowledge of dsm's, Certain manifolds will work better for your application . I would almost bet 4 dollars and 23 cents that given on the type of engine mods , turbo , psi/bar that a manifold might out perform one and vice versa in certain applications.

I bought my magnus and 90mm throttle body for the reasoning of this . "people with fast cars had them and they looked neat" , and as for the throttle body - its bigger so why not . I lost any low end power I had years ago .