PROMO VTT/Fab Factory Manifold(CFD) Flow Testing

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800HP Club (N54)
Platinum Vendor
Oct 24, 2016
1,074
Scottsdale, AZ


We had the opportunity to perform some CFD on the Fab Factory intake manifold (our favorite) and see if the simulation would back our positive experiences and excitement about this beauty.

1.jpg

Figure 1: VTT/FF Manifold in all its beautiful glory.

One consistent thing you’ll find us doing is capturing a lot of data to facilitate better understanding of how push limits and help lay out our next steps in innovating new products. Using instrumentation data provided directly from the shop car, we were able to input real world flow data into the model. For comparison purposes, we picked a moderate (23 psi) and a higher (32 psi) boost level to illustrate the flow profiles. We then compared these results to a 5 psi baseline. This comparison helps show not only how the manifold performs, but the expected flow changes as boost targets and load change. We were excited to see the measurements back our results, check it out:

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Figure 2: 23 psi vs. 5 psi

Stream line view can be useful to help you “see” what’s going on:


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Figure 3: 23 psi vs. 5 psi (streamline)

23 psi is fun and all (especially on an N54 that can breathe properly), but let's have some real fun and turn boost up to 32 psi and see how she does:

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Figure 4: 32 psi vs. 5 psi

As expected, excellent distribution. Once more, the streamline view:

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Figure 5: 32 psi vs. 5 psi (streamline)

The flow data confirms what we’re seeing on the dyno and at the track; the FF manifold does more than just look good (although it’s pretty damn good at that too), doing a great job at keeping cylinder to cylinder variation minimized, even at higher boost levels; this baby is definitely an important part of a top-tier N54 build. Want one? Use coupon code VTTFFMANI for 10% off through New Year’s Day.

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Figure 6: VTT/FF mani in combo with the billet valve cover is a visually stunning high performance combo.



Coupon code: VTTFFMANI for 10% off through New Year’s Day.



Cheers,
Chris
 
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The Convert

Captain
Jun 4, 2017
1,270
Those graphics look pretty good. Not surprising that 3 and 4 get a slightly higher charge velocity, but very interesting to see 1 gets a little bump over 2,5, and 6.

have you guys been using egts in each cylinder to look at how each cylinder varies by difference in air volume? If so, are you using the pi to trim each cylinder to put out the same power? What Tony has done with all the sensors is what I’ve always wanted to do, but just not had the extra time, money, motivation to get after it.
 

[email protected]

800HP Club (N54)
Platinum Vendor
Oct 24, 2016
1,074
Scottsdale, AZ
That's one of the things we use the heavy instrumentation setup for. Tony has sensors all over the car. You learn a lot, especially when things go wonky, and you can "see" how the DME controls things. You can also see when a misfire occurs and compare it to where the ECU thinks it is. To answer your question, most of our fueling -by far- is accomplished with direct injection, minimizing the need for trimming via PI. It could be done, certainly, but we obviously try to start from a place where things are within acceptable tolerances just from quality hardware selection (like this manifold). Also there is value in reducing complexity (when appropriate).

Keep in mind high response sensors aren't long for this world, so it's not like installing a boost gauge and you pretty much expect it to last the life of the car. This level of instrumentation is beyond the average user -by far- but we're consistently surprised so few other vendors instrument like us and use that real-world data.

Chris
 
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gmagnus7

Corporal
Dec 3, 2018
123
Has anyone done this sort of testing with the stock front TB design and compare it to the side TB design (plaz/doc race)? I would imagine the side entry would have better distribution between cylinders but I've never seen any modelling (like this) done for comparison. Maybe I'll take a look at other platforms and see if I can find any.
 

The Convert

Captain
Jun 4, 2017
1,270
Has anyone done this sort of testing with the stock front TB design and compare it to the side TB design (plaz/doc race)? I would imagine the side entry would have better distribution between cylinders but I've never seen any modelling (like this) done for comparison. Maybe I'll take a look at other platforms and see if I can find any.
Data for the stock setup would be interesting to see. I would think 3 and 4 would get a ton of the air charge on the stock design, but the sharp turn into the throttle body and big area change entering the plenum would do a LOT to slow that air down and create some turbulence to allow it to spread out. So, yeah. Would definitely be interesting to see as well. The fab factory manifold is definitely impressive.
 
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[email protected]

800HP Club (N54)
Platinum Vendor
Oct 24, 2016
1,074
Scottsdale, AZ
We did manifold dyno testing way back when, there has to still be a post kicking around, but as far as the level of effort required to see CFD on a stock manifold.... I agree it'd be interesting info and I'm on board right up to the point we have to spend time & money to do so. Might be a cool project for a casual modeler to mess around with maybe? Remember, CFD is cool stuff but usually you'd use it to help the design phase of a product. This case is different in that we brought back the FF manifold after they closed their doors, and we just ran it to see if it backed our dyno and track results. Remember, actual test results always trump analytical results, but still we thought it was a cool validation option.

Chris
 

The Convert

Captain
Jun 4, 2017
1,270
We did manifold dyno testing way back when, there has to still be a post kicking around, but as far as the level of effort required to see CFD on a stock manifold.... I agree it'd be interesting info and I'm on board right up to the point we have to spend time & money to do so. Might be a cool project for a casual modeler to mess around with maybe? Remember, CFD is cool stuff but usually you'd use it to help the design phase of a product. This case is different in that we brought back the FF manifold after they closed their doors, and we just ran it to see if it backed our dyno and track results. Remember, actual test results always trump analytical results, but still we thought it was a cool validation option.

Chris
True story. Every cfd model is wrong, it’s just a matter of how wrong.
 
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[email protected]

800HP Club (N54)
Platinum Vendor
Oct 24, 2016
1,074
Scottsdale, AZ
Yeah I love it, think it's a great and useful tool but no way in hell would I hang my hat on CFD. Aerospace wise, the data we capture in order to have input conditions correct is absolutely enormous, and we still use it as a guide. Awesome tool, just always take with grain of salt. Best pictures ever though, right?
 

SJ_1989

Sergeant
Aug 7, 2018
311
Illinoisssss
CFD is great. It's best used to show direction and a delta improvement/reduction in performance during design rather than the absolute values. It can be rather accurate though if set up correctly. Garbage in garbage out gives simulation a bad rep.

Do you have pressure contour plots? Do you see a bottleneck at the inlet at high boost (flow) conditions where you could benefit from making it larger?

I agree it'd be interesting info and I'm on board right up to the point we have to spend time & money to do so.
If someone has a 3D model of the OEM manifold I'd be willing to give it a whirl. I'm familiar with Ansys but been looking for a project to get my feet wet in SolidWorks CFD. Keep in mind it wouldn't be an apples to apples comparison since I wouldn't know the solver used, mesh properties, fluid properties, etc unless that info were to be shared.....but it'd be an interesting comparison nonetheless.
 

[email protected]

800HP Club (N54)
Platinum Vendor
Oct 24, 2016
1,074
Scottsdale, AZ
I have some old cfd flow analysis photos from back when they were still in business if you dont mind me sharing. one from prototype and one from current production comparing the two.
I have no idea as to the validity of it, I know they certainly weren't done with input data gleaned from our shop car but might be interesting to look at. Thing with CFD is, as mentioned above, garbage in garbage out. That's not to say it's junk, just I know they didn't use our boundary conditions.

Chris
 

[email protected]

800HP Club (N54)
Platinum Vendor
Oct 24, 2016
1,074
Scottsdale, AZ
CFD is great. It's best used to show direction and a delta improvement/reduction in performance during design rather than the absolute values. It can be rather accurate though if set up correctly. Garbage in garbage out gives simulation a bad rep.

Do you have pressure contour plots? Do you see a bottleneck at the inlet at high boost (flow) conditions where you could benefit from making it larger?

If someone has a 3D model of the OEM manifold I'd be willing to give it a whirl. I'm familiar with Ansys but been looking for a project to get my feet wet in SolidWorks CFD. Keep in mind it wouldn't be an apples to apples comparison since I wouldn't know the solver used, mesh properties, fluid properties, etc unless that info were to be shared.....but it'd be an interesting comparison nonetheless.
Yep, we have a full analysis, in the interest of keeping things reasonable we just posted the "take home" message here. In theory increasing throttle size could help, it's not a bottleneck yet but maybe someday. The cost involved would be enormous. Probably want to for the first 15-1600 whp N54 though, if that ever becomes a thing. More likely they'll just use two existing throttles. Interesting to speculate. I don't have a 3D model of the oem mani, have fun drawing that up. The effort/reward ratio just isn't there IMO, but there may be some sick twisted individual that wants to spend time recreating *gasp* stock parts. :grin:

Chris
 
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[email protected]

700HP Club (N54)
Oct 19, 2016
522
NY & AZ
I have no idea as to the validity of it, I know they certainly weren't done with input data gleaned from our shop car but might be interesting to look at. Thing with CFD is, as mentioned above, garbage in garbage out. That's not to say it's junk, just I know they didn't use our boundary conditions.

Chris
its straight from shawn prior to me purchasing the intake from him
 

[email protected]

800HP Club (N54)
Platinum Vendor
Oct 24, 2016
1,074
Scottsdale, AZ
We had quite a few manifold sales over Black Friday, and since CFD results were released. Most ordered black but we did get a few clears. While usually, we love Black here at VTT. These Clear manifolds are things of beauty! The customers are going to be head over heels in love once they see these! :hearteyes:
 

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Panzerfaust

Lieutenant
Jul 3, 2018
620
Chicago
In theory increasing throttle size could help, it's not a bottleneck yet but maybe someday. The cost involved would be enormous. Probably want to for the first 15-1600 whp N54 though, if that ever becomes a thing. More likely they'll just use two existing throttles. . :grin:

Chris
Its funny to see this post (even if I'm a bit late) because while I was in Peru my only way to get part of my car-modding fix was looking at my emails, and I saw that ECS is offering a large-bore (84mm?) throttle body retrofit for the older V8s now and was curious if itd also be beneficial for people running high boost and upgraded turbos, if it was possible to have the DME control that TB. I dont imagine it'd be very hard to retrofit the physical part since you could either drill & tap threads or use a small plate adapter, and if needed port the IM inlet, but I have no idea on the software side of things what would need changed (if anything).

I was actually planning on emailing you or Tony about it to see if either of you have tried such a thing since you guys definitely have the most experimental shop car and Tony has no aversion to trying new things. I know throttle body upgrades generally arent the biggest HP gains you can get, but from my time in the LS world I also know that with a larger IM and TB they do allow for noticeable gains even while NA. I'm assuming since you're speculating on the different routes one could go that you guys havent tried such a thing, though?

Even if the stock TB isn't necessarily a restriction, surely there'd be some form of gain by increasing flow there on a FI application like ours. I mean we make 700-800whp with horrible exhaust ports so they aren't usually considered a major restriction either, but we've seen what larger exhaust ports can do too.
 

Chill

Lurker
Jan 28, 2019
11
Hey Chris, your manifold is really a piece of beauty ^^ but air intake manifolds are since BMW Motorsport in real Carbon due to intake sounds and weight....
So for me as a Timattack Driver, I do search every singel lb to get off... would be nice to see some light weight parts in general ^^
 
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