FRS / BRZ Intake Manifold - Development Thread - FT-86SpeedFactory by Velox

[hmong337]

too good not to sub. subbed!

[Sypher]

Originally Posted by djliquidsteele

So with FI in mind, specifically supercharged, in theory, will something like this allow the engine to keep making power past 7000 rpm. Stock seems to die off and it seems no matter how much air you try to shove in there, it still dies off toward redline.

My stupid, uneducated guess is that the problem is the stock heads. I've see the intake runners and the look like they could use a lot of improvement.

[dem00n]

This i like...

[eric6]

Originally Posted by djliquidsteele

So with FI in mind, specifically supercharged, in theory, will something like this allow the engine to keep making power past 7000 rpm. Stock seems to die off and it seems no matter how much air you try to shove in there, it still dies off toward redline.

See below...

Originally Posted by Calum

Without testing it's impossible to tell. The choke point could be the intake manifold or the head, or both.

Great response. It's difficult to know.

[zooki]

Originally Posted by cdrazic93

I was about to ask (I think this has already been answered) since both intake runners seem to feed two cylinders at once, wouldn't the piston firing order cause a difference in pressure in the manifold? or is that what the intermediate hose is for?

I would have to think that the large runners that connect the two plenums would do more to balance it out than the small hose at the bottom. Just guessing by looking at the design, on a NA build this intake would kill what little low end these motors have due to the extremely short runner length between the plenums and the cylinders, with those rather large plenums above them that will slow down the air. Should be a great forced induction setup though. I could be totally wrong though...

[Captain Snooze]

Originally Posted by Calum

The choke point could be the intake manifold or the head or the wallet.

Fixed.

[Captain Snooze]

Originally Posted by zooki

would kill what little low end these motors have

*protest*
I think the low end torque is quite adequate. Between approximately 2500-3300 rpm is very close to max torque on a standard engine.

[Captain Snooze]

Originally Posted by eric6

From previous knowledge it points to be a top end, FI geared, intake manifold.

Noob hypothesis coming up. Please be gentle.
I would have thought that with forced induction imperfections in the manifold design would be hidden. That is, air is forced in (and out) so it hides poor design. (I am not suggesting the FA20 is poorly designed.) I would have thought that the biggest gain, percentage wise, would have been for normally aspirated and even then, given the standard rev limit, it would not be a huge gain. Significant but not huge.

[eric6]

Originally Posted by zooki

I would have to think that the large runners that connect the two plenums would do more to balance it out than the small hose at the bottom. Just guessing by looking at the design, on a NA build this intake would kill what little low end these motors have due to the extremely short runner length between the plenums and the cylinders, with those rather large plenums above them that will slow down the air. Should be a great forced induction setup though. I could be totally wrong though...

Time will tell... this is what prototypes are for . We can make educated guesses but until it's been strapped on a dyno for a good day to figure out how it behaves, your guess is as good as mine. I'm looking forward to seeing how it behaves as well.

Originally Posted by Captain Snooze

Noob hypothesis coming up. Please be gentle.
I would have thought that with forced induction imperfections in the manifold design would be hidden. That is, air is forced in (and out) so it hides poor design. (I am not suggesting the FA20 is poorly designed.) I would have thought that the biggest gain, percentage wise, would have been for normally aspirated and even then, given the standard rev limit, it would not be a huge gain. Significant but not huge.

No idea to be honest. FI tends to favor larger plenum volumes.

[OkieSnuffBox]

Originally Posted by Captain Snooze

Noob hypothesis coming up. Please be gentle.
I would have thought that with forced induction imperfections in the manifold design would be hidden. That is, air is forced in (and out) so it hides poor design. (I am not suggesting the FA20 is poorly designed.) I would have thought that the biggest gain, percentage wise, would have been for normally aspirated and even then, given the standard rev limit, it would not be a huge gain. Significant but not huge.

This works to a point, but cams/headwork/intake manifolds can really open big gains on FI depending on what the choke point is.

On some big power BMWs just a little port work/cams is netting ~15% HP/tq on boosted applications at lower psi, since the engine is flowing more air.

[*KID*]

I think imo its a pretty good design.

Extended runners will have similar results as crawford, but more top end cause of the 2 long tube design inlet. Shouldn't see any decrease in torque or decrease in hp.
That tube design to balance pressure is thumbs up.
This piece paired with a bigger tb and flywheel, ahhh this is going to keep me NA. I like it a lot

[s30series]

Originally Posted by *KID*

I think imo its a pretty good design.

Extended runners will have similar results as crawford, but more top end cause of the 2 long tube design inlet. Shouldn't see any decrease in torque or decrease in hp.
That tube design to balance pressure is thumbs up.
This piece paired with a bigger tb and flywheel, ahhh this is going to keep me NA. I like it a lot

Moreso the velocity stacks inside the plenum.....velocity stacks do wonders if the system is designed right...crawford merely extends runner length, and also puts the port injectors at an awkward angel (kinda sprays the intake walls)

[eric6]

Originally Posted by *KID*

I think imo its a pretty good design.

Extended runners will have similar results as crawford, but more top end cause of the 2 long tube design inlet. Shouldn't see any decrease in torque or decrease in hp.
That tube design to balance pressure is thumbs up.
This piece paired with a bigger tb and flywheel, ahhh this is going to keep me NA. I like it a lot

Thanks for the compliment .

Originally Posted by s30series

Moreso the velocity stacks inside the plenum.....velocity stacks do wonders if the system is designed right...crawford merely extends runner length, and also puts the port injectors at an awkward angel (kinda sprays the intake walls)

This was basically our thoughts behind the design. Although everything is conjecture until it's on the dyno.

If nothing else, we created the most divided theory manifold to date .

[Turdinator]

@eric6 any thoughts about including the ability to install the port injectors above the trumpets for people doing hardcore NA builds?