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Old 01-09-2020, 08:57 AM   #451
xAv7
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any data from AMS one ?
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Old 01-09-2020, 09:40 AM   #452
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Default Who's the top dog right now?

What's the consensus right now on what manifold is the best for 500+ HP?

Which one if you are focused on good torque and still want 500 HP and 7,500-8,500 RPM's? Thinking road race application.
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Old 01-11-2020, 04:43 AM   #453
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process west
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Old 01-13-2020, 10:24 PM   #454
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Quote:
Originally Posted by Hyper View Post
process west
I'm going to disagree because Glynn does track work. He'll want a longer runner than what the PW has. He also won't want a gigantic plenum further hurting transient response.

Process West is currently everyone's best option for a straightline car OR a track car with big power and the ability to keep high revs, or a good ALS system.

Current bang for the buck is still the SOHC long runner, modified.
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Old 01-14-2020, 09:31 AM   #455
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Thanks Micah for the input. I have a new NA ready to go onto something...

However, I have been concerned by comments I've read about how the flatter angle of the injectors in an NA is inferior. I have managed to design my new intake where I don't need to have any phenolic spacers at all. That will lessen the supposed issue of the injectors spraying on the manifold wall and spacer rather than into the mainstream of the head passage. As I try to improve efficiencies this one issue eats at me!
I have made 467 on pump gas with Torco (effective 105 octane) @ 24 PSI.
This with stock bore/stroke 8.5 CR and Kelford 272's. I believe this is at least average efficiency without alcohol, etc.
So, I'm on the fence about going to a fancy new manifold...or stick with what I've come up with. Thus the question about what would be ideal for what I'm trying to do.
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Old 01-14-2020, 10:55 AM   #456
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Quote:
Originally Posted by Homemade WRX View Post
I'm going to disagree because Glynn does track work. He'll want a longer runner than what the PW has. He also won't want a gigantic plenum further hurting transient response.

Process West is currently everyone's best option for a straightline car OR a track car with big power and the ability to keep high revs, or a good ALS system.

Current bang for the buck is still the SOHC long runner, modified.
Why not the SOHC short runner modified to mate to stock TGV's? People are already modifying them to remove EGR, etc, so a few extra cuts to fit the TGV's shouldn't be much and you don't need spacers/risers/whatever for fueling.

I've got a few SOHC shorties that I'm modifying for my autox car.
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Old 01-14-2020, 10:55 AM   #457
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^ Shoot you beat me to it, but I like how you think

I always wondered about this as well.
What about the short runner SOHC manifold mounted to WRX TGV housings? It's not the "cleaner" setup most go with but it would maintain the same fuel spray angle since that is dictated by the TGV housings. *Although not certain if the original WRX fuel angle is desirable or not.
Also thought about the o-ringed spacers Aluminati makes that go between the manifold and TGV flanges. Since those could be made in varied thickness, once could presumabily play around with runner length without impacting the fuel spray orientation. Just some thoughts I guess...
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Old 01-14-2020, 10:58 AM   #458
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You could always go with the SOHC short runner manifold although they're harder to find. then you can keep with normal turbo TGV housings.

I did have to pretty heavily modify it to get it to bolt up properly though.

As much as it may potentially hurt idle and such i've been tempted to add fuel injector bungs to basically have the injector fire straight down the intake manifold. Most of the larger aftermarket injectors seem to have a narrower spray pattern.
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Old 01-14-2020, 11:37 AM   #459
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Well apparently we all had the same idea at the same time hah.

There are some pics of how i modified the intake manifold to bolt to the turbo style TGV on my instagram.
The 2 pairs of center holes lines up. All 8 (I think, 4 per side) of the outer bolts are quite a bit off. I ended up cutting them all off and welding on new aluminum spacers that i got from McMaster. I was quite a pain to weld up for an amateur like myself.
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Old 01-14-2020, 12:16 PM   #460
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Quote:
Originally Posted by Barge View Post
Well apparently we all had the same idea at the same time hah.

There are some pics of how i modified the intake manifold to bolt to the turbo style TGV on my instagram.
The 2 pairs of center holes lines up. All 8 (I think, 4 per side) of the outer bolts are quite a bit off. I ended up cutting them all off and welding on new aluminum spacers that i got from McMaster. I was quite a pain to weld up for an amateur like myself.
A grinder and paint make me the welder I ain't.
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Old 01-16-2020, 12:18 AM   #461
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Quote:
Originally Posted by subydude View Post
Why not the SOHC short runner modified to mate to stock TGV's? People are already modifying them to remove EGR, etc, so a few extra cuts to fit the TGV's shouldn't be much and you don't need spacers/risers/whatever for fueling.

I've got a few SOHC shorties that I'm modifying for my autox car.
They're pretty much the same in my mind. It's more or less the long runner but in two pieces...and keeps the WRX TGV's if modded.

Removing EGR is easy.

I am now curious what the difference in runner length and plenums might be between these. I remember my Mom's 05 Outback had the two piece manifold and they were quite pricey even back then compared to the once piece manifolds...for some reason.
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Old 01-16-2020, 08:14 AM   #462
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Quote:
Originally Posted by Homemade WRX View Post
They're pretty much the same in my mind. It's more or less the long runner but in two pieces...and keeps the WRX TGV's if modded.

Removing EGR is easy.

I am now curious what the difference in runner length and plenums might be between these. I remember my Mom's 05 Outback had the two piece manifold and they were quite pricey even back then compared to the once piece manifolds...for some reason.
I've got both of them so I suppose I could try to get some measurements. Just based on memory I don't think they're much different if at all.

My understanding is that the 2-piece only came on the ULEV cars in california and some other random locations so it's more expensive to buy used because there see to be less of them. They must also use a unique TGV because as I stated above the bolt pattern is quite different.

They usually sell for upwards of $200. You can get the long runner version for half that often times.
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Old 01-16-2020, 12:57 PM   #463
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I bought my two short runner 2.5i manifolds for just over $100 combined on ebay from a junkyard.

The plenum looks exactly the same as do most of the vacuum ports. I figured it was just like the JDM long runner vs standard runner STi manifolds. Basically no difference other than the casting where the TGV used to be.
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Old 01-16-2020, 03:59 PM   #464
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Quote:
Originally Posted by Scargod View Post
What's the consensus right now on what manifold is the best for 500+ HP?

Which one if you are focused on good torque and still want 500 HP and 7,500-8,500 RPM's? Thinking road race application.
I would recommend the 08+ WRX plastic manifold. We gained power E-V-E-R-Y-W-H-E-R-E in the rev range at 700whp (40psi boost) and had no problem supporting those kinds of revs.

IMO it is the most symmetrical, ideal sized runners, and optimized plenum design OEM intake manifold you can get. You can find them for cheap too
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Old 01-16-2020, 04:16 PM   #465
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I even have one for sale right now...
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Old 01-16-2020, 04:44 PM   #466
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Quote:
Originally Posted by subydude View Post
I bought my two short runner 2.5i manifolds for just over $100 combined on ebay from a junkyard.
You got a good deal then. They usually are priced much higher.
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Old 01-16-2020, 05:04 PM   #467
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Quote:
Originally Posted by Barge View Post
You got a good deal then. They usually are priced much higher.
It's why I bought two. I'm cutting/grinding the first one down and learning what all I need to do there. If it comes out good I have a spare for later or another car. If it doesn't, I have a spare for right then
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Old 01-17-2020, 12:32 AM   #468
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Quote:
Originally Posted by Scargod View Post
Thanks Micah for the input. I have a new NA ready to go onto something...

However, I have been concerned by comments I've read about how the flatter angle of the injectors in an NA is inferior. I have managed to design my new intake where I don't need to have any phenolic spacers at all. That will lessen the supposed issue of the injectors spraying on the manifold wall and spacer rather than into the mainstream of the head passage. As I try to improve efficiencies this one issue eats at me!
I have made 467 on pump gas with Torco (effective 105 octane) @ 24 PSI.
This with stock bore/stroke 8.5 CR and Kelford 272's. I believe this is at least average efficiency without alcohol, etc.
So, I'm on the fence about going to a fancy new manifold...or stick with what I've come up with. Thus the question about what would be ideal for what I'm trying to do.
The effect of that angle will depend on how well the injectors atomize the fuel and the velocity of the air flying through it. Would be really awesome if someone could design a transparent test jig with a variable injector angle to mimic typical higher flowing injectors with pressure and velocity of a running engine in the runner. It would seem best to have very finely atomized fuel coming from the injectors, would be less likely to hit the runner walls and be even more evenly mixed by the time it entered the cylinders.

Quote:
Originally Posted by Barge View Post
You could always go with the SOHC short runner manifold although they're harder to find. then you can keep with normal turbo TGV housings.

I did have to pretty heavily modify it to get it to bolt up properly though.

As much as it may potentially hurt idle and such i've been tempted to add fuel injector bungs to basically have the injector fire straight down the intake manifold. Most of the larger aftermarket injectors seem to have a narrower spray pattern.
I've noticed some injectors being demonstrated with a narrow pattern, but wonder what pressure they are using during those tests. Higher pressure could atomize the fuel more and create a wider pattern. The better atomized fuel would be less likely to hit the runner walls.

Quote:
Originally Posted by KillerBMotorsport View Post
I would recommend the 08+ WRX plastic manifold. We gained power E-V-E-R-Y-W-H-E-R-E in the rev range at 700whp (40psi boost) and had no problem supporting those kinds of revs.

IMO it is the most symmetrical, ideal sized runners, and optimized plenum design OEM intake manifold you can get. You can find them for cheap too
Look here now, I haven't even got my big plenum long runner na manifold bolted to the engine and you're making me search threads about the plastic ones. I already prefer plastic for the insulation and less weight factor, don't be tempting me with those dyno results.
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Old 01-17-2020, 04:13 AM   #469
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The plastic ones have always been the best. The plastic one on the ez30 is vastly superior too.
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Old 01-17-2020, 10:58 PM   #470
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Has anyone tested the plastic intake manifold from the 2010-2012 2.5 legacys?
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Old 01-18-2020, 03:22 PM   #471
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Quote:
Originally Posted by Bo0stcreep View Post
Has anyone tested the plastic intake manifold from the 2010-2012 2.5 legacys?

I was wondering the exact same thing. It's definitely a nicer looking intake
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