Intake manifolds testing - April 3

[JohnTSI]

Originally posted by Sleepr DSM
They weren't tuned for a reason.

Yeah and I understand that reason, but its just like strapping on a t25 a 16g a gt35r and a t88 and leaving all else the same at same boost levels, like 15 psi, its pointless to look at the dynographs. You would say the t25 was the best because it has the best spool up and hed the power to redline or perhaps the 16g. But the Gt35R and T88 are most certainly not turbos designed to be operated in that area. Same thing goes for these manifolds, thats why the stock manifold help up so well its working in its designed area. Like the people who setup the test said its not about the dyno numbers its about airflow with tuning any one of these could have outperformed the rest substantially. SOme designed for high air flow high rpm power others for low. You wouldnt see that in ths test by those dyno numbers. Just like in other tests where particular ones picked up 30-40hp over stock ones its all in the tuning. The information is there just not really in the dyno numbers.

And thanks again for the results.

 

[Wheels-a-turnin]

Originally posted by GRNDSM
What are you talking about?

If this test told us anything is that the old Venom intake outperformed just about anything else out there. Returning a NEW style Venom intake, based on this test makes no sense…
\

I'm saying those gains arent worth 500+shipping for me!

 

[MNGSX]

The test really did't surprise me...

Smallest plenum spooling first etc....

The Bjs and Magnus did'nt taper off up top like the others.

The magnus seems a little easier to install from what I have read on installs of both... Basically running the 1g for a while yet does'nt bother me untill I get the magnus or an FRH..... The FRH blows out gaskets as opposed to welds in the case of a NOS ooops... There are alot of attributes to consider. I'm more concerned with the general shape of each manifolds power curve as opposed to the others. Tuning is all on the tuner... One group could tune each mani with the same car and get different results than another.

 

[turbobrian]

i have never blow out a gasket on my frh manifold.

 

[tanner261]

Airflow is directly related to HP, HP is directly related to torque, torque is directly related to VE.

The graph of airflow vs. RPM is the best representation on how the manifold will perform. I was surprised to see just how much the aftermarket intakes lose torque compared to a stock 1G below 6k RPM. This all makes sense because all the same principles appy to a boosted application that apply to a N/A application. The turbo makes up for some of the losses down low, but the losses are still there.

Seems you will only see gains in 1/4 mile times if you shift above 7k RPM. I know most people who install an aftermarket manifold do, as they should. If I had a Magnus/Venom/etc manifold on my 16G car, I'd be shifting at 8k, and may see a 3 mph gain in the 1/4. Not worth it to me, as my car is used for daily driving and autox.

This makes me want to try out my Cyclone manifold even more. With some HKS cams there should be some nice gains in the midrange.

 

[Sleepr DSM]

Originally posted by tanner261
Airflow is directly related to HP, HP is directly related to torque, torque is directly related to VE.
The graph of airflow vs. RPM is the best representation on how the manifold will perform. I was surprised to see just how much the aftermarket intakes lose torque compared to a stock 1G below 6k RPM.

Personally I believe that if one wants to evaluate one manifold against a number of others, that Airflow vs. TIME is a more accurate way to see the real time differences between Intake Manifolds. Why do I say that?

(((Tanner, someone just let me know that you REALLY, REALLY, know what you are doing in regard to airflow. If I am making an ignoramus of myself, please make it painless when you shoot me. I'm Joe nobody using excel to display the numbers to give me the information in a manner that I understand more easily for the sole sake of comparison.)))

In an "airflow vs. RPM" comparison of six intake manifolds, TIME is ignored. Every manifold will be at a different RPM three seconds into the test. Manifold A is at 4000 rpm's 3 seconds into the test, while manifold B is at 3600 rpms 3 seconds into the test. Is it fair to compare Manifold A with Manifold B on an RPM scale, if Manifold A hits 4000 rpms a full second faster than Manifold B? The focus of this test should be Airflow vs. TIME. At 1 second into the test, which manifold flowed the most air? At 2 second, at 3 seconds, and so on?

Tanner, tell me what you think of the lower rpm performance of the after market manifolds in this graph that displays Airflow vs. TIME. - especially the graph at the bottom that shows the 1G manfold. Scroll to the bottom of the page in the link
http://www.paragon.bz/g/page7.html

According to the text data from the DSMlink, at time stamp 5311000 the 1G manifold is at 5499 rpms. The Venom is at 5716 rpms. (an example of why comparing the two at a given rpm would not be fair, IF you want to know which one is flowing more air over a given period of time) I am eager to hear differing opionions on the matter. I'm not afraid to look like fool. I'm trying to describe how, after looking at the data in the tests.. in my opinion the best way to pick your manifold is by using a air flow vs. time chart, not an airflow vs. rpm. The time it takes to reach a given rpm changes with every manifold!

 

[Sleepr DSM]

I'm using the dsmlink text data to display the airflow of the manifolds in TIME rather than RPM. The test was xx seconds long. How much air was each manifold flowing from zero seconds to xxxxxx time stamp, regardless of engine rpm? That is what I am showing below using the data from the DSMlink, copied into an excel spreadsheet. This is all for sake of comparison. RMDSM.ORG rules the original data and I will remove it as per their request.
Links are in alphabetical order:

Extreme/Hogan vs. 1G

Magnus vs. 1G

Magnus, BJ's and 1G

Venom vs. 1G

Venom BJ's and 1G

Venom Dejon and 1G

Venom Extreme and 1G

Venom Magnus and 1G

 

[tanner261]

Airflow vs. RPM is time dependent, RPM ->revolutions per minute. The more airflow you have at a given RPM, the more torque generated, the faster the engine will accelerate. HP is work per unit time. I do not think that you can use time stamps from the datalog to compare this data. I do not see how the time at which the datalog was started could be exactly the same for every test.

Take your first graph for example, Hogan vs. 1G. Do you think it is possible for the 1G manifold to flow the same amount of air at the same rate as the Hogan towards the end of the dyno pull? Short runners will lose power in the lower RPMs, the longer 1G runners will have more power in the midrange (3k-6k) than a SMIM.

Also, remember that this data is taken from a dyno, it is not road load on a perfect surface. The only way to compare this data is airflow vs. RPM or HP vs. RPM.

I plotted the data using the Dynojet software and the HP numbers are scaled so that the actual HP is not shown. This could be that the owner of the car doesn't want everyone to know, 55 lb/min is a lot more than 250 HP at the wheels.

 

[Sleepr DSM]

Originally posted by tanner261
Airflow vs. RPM is time dependent, RPM ->revolutions per minute. The more airflow you have at a given RPM, the more torque generated, the faster the engine will accelerate.

Tanner, I appreciate your input. I understand what RPM means. I understand the value of looking at a single manifold's airflow characteristics at a given revolution per minute.
But, the rate at which the manifold runs through the rpm band is different for every manifold. That rate can only be measured in time. Time helps us to see how a manifolds air flow characteristics affected how fast it traveled through the RPM band relative to other manifolds. With a air flow vs. rpm test we can only see where this manifold was at this RPM. If I want to see how fast that airflow and rpm were hit in comparison to another manifold, I cannot see it using an airflow vs. rpm test only. Heck, I wish I knew how to make a chart showing all three! That would rule!

Given, the time stamps are not supremely accurate. All of the "Zero" time stamps or (samples per second) started at aproximately 3500rpms. Each manifold would have taken a slightly different amount of time to reach 3500 rpm's. That difference is lost to us. But, after 3500 rpms using airflow vs. time stamps, we can see aproximately which manifold flowed more air per second after 3500 rpm's. I am not saying that airflow vs. time is "the best way" to look at the data, but to my eyes it reveals the curves of air flow in a manner that is easier to interpret.

The manifold that is flowing the most air at timestamp xxxxx is what I look for. If Manifold A is 500 rpms ahead of Manifold B at the same point in time, how can it be fair to compare the airflow between the two manifolds at the same rpm point??
The timestamps from the DSM link data are actually very close from zero to the end of the data for all of the manifolds. So as not to waste my time, I studied them to verify that before making a graph using that data. At the very least, they are no worse in accuracy then the RPM samples.

To someone like yourself with years of studying airflow characteristics, it is probably far easier to use an air flow vs. rpm chart to see the value of six different manifolds. I'm just Joe Nobody playing around with numbers and asking questions. If my way of looking at the data is misleading in your opinion, then I should remove it?

You've given me a cool idea for some more charts...
- Gabe

 

[Got Grip]

Originally posted by tanner261
I plotted the data using the Dynojet software and the HP numbers are scaled so that the actual HP is not shown. This could be that the owner of the car doesn't want everyone to know, 55 lb/min is a lot more than 250 HP at the wheels.

You need to select "Total Horsepower". You are displaying the HP for just the front rollers...4wd dyno, so there are two rollers. That will make MUCH more sense once you do that.

I have to agree that there are too many variables in the airflow versus time theory. If you are interested in which manifold is accelerating through the RPM range quicker, look at horse power, or look at where in the RPM band the airflow begins to rise. This should tell you what you are looking for, but with less variables. That is my theory at least.

Thanks Hal and all who were involved in this test.

 

[Violater101]

Like Leon said, something definately looks odd in that the HP falls off after 7500. I would not expect that from a SM intake.

 

[pneumo]

Re: airflow/time.

In trying to plot airflow per time starting from the beginning of the dyno pull, you will end up with a summary of what's called "area under the curve". This can be usefull in determining how much power is made as the engine revs through each gear, but it's not very usefull outside of the useable powerband, as in, pre-spool. If you want to plot airflow/time, find your shift points including the max rpm (when you shift to the next gear) and min rpm ( where the rpm falls to after changing gears), then add the total airflow between those two points, or you could also subtract the time stamps to see how quickly each manifold went throught that rpm band. That would show something like a HP summary.

This is just speculation, but I wonder if power fell off in the higher rpms due to a restriction somewhere else? They did say they used a stock 1G throttle body. Maybe that limited the airflow enough to cause the power to drop at high rpm.

 

[MNGSX]

Originally posted by turbobrian
i have never blow out a gasket on my frh manifold.

What I am talking about is in the event of an N20 backfire the gaskets blow and the cast manifold tends to stay in one piece as does the cars hood.

Welded sheet metal manifolds are lighter but will go to pieces should the N20 system not work properly and fill the intake manifold.

 

[mitch83]

just looking at the airflow plots it looks to me that the venom came out on top.
mitch

 

[Sephroth57]

it seems every link in this thread that should lead to data is broken... so whats the results. was there a obvious "winner", what is the best for general street/drag

 

[STECARS]

it seems every link in this thread that should lead to data is broken... so whats the results. was there a obvious "winner", what is the best for general street/drag

For general street , IMO the 1g manifold.

 

[blue1]

Hate to be a stick in the mud but its a pity they didn't have time to run the JDM cyclone, i think their would have been a lot more suprises!! It was a great test it has opened a few eyes and shut a few mouths, good job guys!!!!

 

[Nautica985]

links dont work anymore

 

[DSMJim]

Just to add info into this thread about the Magnus unit, check out my before after results in the 1/4mile from the Magnus unit.

http://www.dsmtuners.com/forums/showthread.php?t=129494

The long and short of it was 12.55 @ 109 became 12.13 @ 113mph from the Magnus SMIM and 1st gen 60mm TB.

This info added just so additional info can be linked across for easier access for those searching.

 

[pneumo]

Thanks for the info, Jim. I think your post/thread tells more about the Magnus vs. stock manifolds than the IM shootout did. I remember one of the disclaimers the testers wrote, something like 'Don't compare the HP numbers because the manifolds were untuned.' Well what's the point of doing the test then? You obviously made more HP with it. Why didn't the test predict that? (hypothetical questions ^ )

When the test results came out one impression was that all the SMIM's showed improvements at high rpm, but a reduction in flow at low and mid rpm. So the real question is, was this your experience as well? Did you feel the top end increase and low end drop off? What were your shift points before and after? Thanks again for your input.

 

[nanokpsi]

Thanks for the info, Jim. I think your post/thread tells more about the Magnus vs. stock manifolds than the IM shootout did. I remember one of the disclaimers the testers wrote, something like 'Don't compare the HP numbers because the manifolds were untuned.' Well what's the point of doing the test then? You obviously made more HP with it. Why didn't the test predict that? (hypothetical questions ^ )

When the test results came out one impression was that all the SMIM's showed improvements at high rpm, but a reduction in flow at low and mid rpm. So the real question is, was this your experience as well? Did you feel the top end increase and low end drop off? What were your shift points before and after? Thanks again for your input.

HP numbers ahouldn't matter at all. The reason being is that airflow is potential horsepower, thius the manifold that flows the most has the potential to make the most power. Airflow is not really going to change with tuning. Leaving all the settings alone and asking not to take hp into consideration takes possible bias out of the equation.(from better tuning of a particualar manifold. This was a great test! Thanks a lot Hal and all of the other contributors!

 

[na90dsm]

umm....

 

[Sephroth57]

umm....

and without the results link... whats the point of this thread really without the results.. i looked on RMDSM.org theres no info on this testing at all

 

[pneumo]

Ok, I was PM'd to reopen the thread and here are the results.

nabr.jayntguru.com/shootout/

What do you mean, "the links don't work"? I just clicked on the link and the results came up just like they always do.

What link are you guys using?

 

[myblack98gst]

just to back up dsmjim... I spoke with a guy this weekend who used the dejon tool manifold. he said he gain 30 hp just from bolting it on and doing some minor tuning.. did not state any difference in spool up or peak power. he was running a 90 fwd with a pretty big turbo