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View Poll Results: Interested in new intake manifolds?
Yes, I need the power. 58 93.55%
No, don't need it. 4 6.45%
Voters: 62. You may not vote on this poll

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Old 09-28-2007, 03:28 PM   #26
saintluciascooby
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hehehe I have 1200cc side feeds!!!!!!!!!!
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Old 09-28-2007, 03:29 PM   #27
dan avoN7
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I think it would be best to have the intake manifold just replace the actual manifold and not the TGV part. This way it is compatible for people who run top and side feeds. Also I have my TGV's machined to fit my larger injectors and would hate to have to machine a nice new manifold.

I'm not sure how Mitch's manifold performs but I love the fitment of his and how the throttle body goes straight out instead of angling up like on the stock intake manifold. Makes routing the IC piping easy.

http://smdandb2.smugmug.com/photos/166131238-M.jpg
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Old 09-28-2007, 07:49 PM   #28
DeliciouSpeed
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/\ I agree. But then I think they'd need to make three manifold types to please everyone. If they just did the TGV everyone could use it in any configuration. Yes it's more complex than it really needs to be. But their gonna want to keep things simple. Good thing is with a good port matching the housings will still work well.
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Old 09-28-2007, 10:41 PM   #29
shvrdavid
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What we really need is a modular design that can do all of the above...

The biggest problem I see with our engines is the inability to match the entire setup...
Every setup could use a slightly different intake design...
If someone were to come up with a modular system, it would sell for sure...

As an example of what I mean consider this...
If you are using a 30r, your peak torque will be about 4500 rpm (just as an example) with the stock intake and engine...
The reason for this is the VE of the engine at that rpm based on the entire setup...
If you put higher duration cam in, the rpm goes up...
If you port the heads it goes up...
Now look at why it goes up without changing the intake...
Peak torque always falls between where the cams are designed to have max torque, and where the rest of the intake system and exhaust system are designed to reach max torque (highest VE comes to mind)...

When you build an engine, you should know where you want peak torque to come in at...

Consider these numbers:
700 ft/lbs at 4000 rpm is 533 horsepower (flywheel)
700 ft/lbs at 5000 rpm is 666 horsepower
700 ft/lbs at 6000 rpm is 800 horsepower
700 ft/lbs at 7000 rpm is 933 horsepower
700 ft/lbs at 8000 rpm is 1066 horsepower

So where do you want your peak torque to be at???
And how wide do you want the range to be???

The only way to achieve peak torque at a certain rpm is to design the entire engine around that number...
Every little detail effects where that peak will be, and how quickly VE falls off after that point...

A modular intake system would be adaptable to just about everyones setup, and peak torque goals...

For what its worth, since I am plugging numbers in here...
To break 1000whp with our little boxers, you need to make at least 1000ftl/lbs of torque at 7000 rpm (Flywheel)... thats 1333 flywheel hp.......

I am curious to see the design you come up with, and the changes it makes on the dyno sheet...
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Old 09-29-2007, 09:53 AM   #30
SubiSam
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Sport compact car has an STI in thier ultimate Street Car Challenge that has a reverse mounted stock manifold that was modified, and there is an A/C compressor still on the car, so it obviously can be done so that we keep our A/C.
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Old 09-29-2007, 01:39 PM   #31
Homemade WRX
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yes, a reversed manifold with AC on a GD has been done many many times before...I have to see it done on a GC because of the lower hood line. I'm curious to see how Vern's turns out.

and David is spot on without going into very detailed description...everything you do to a motor will change where its peak VE and its duration.
The higher the rpm the "easier" it is to reach a hp goal

Last edited by Homemade WRX; 09-29-2007 at 01:44 PM.
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Old 09-29-2007, 09:15 PM   #32
STiBottom
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Reverse manifold keeps the piping of the intercooler shorter and that reduces lag which only becomes an issue with really big turbos.

I personally don't mind turbo lag though cause its kind of like foreplay. Oh and the Magnus manifold is a thing of beauty.
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Old 10-01-2007, 07:34 PM   #33
subaru5614
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so am i now,i know how much room there is and have one i made with longer runners and larger plenum i ll be installing on a customers car soon
i hope the original poster has good luck if he chooses to persue this venture i ve been ask to make a few of by different people but i m in the middle of my subie build at this time so i don t have much spare time

looking forward to seeing his style
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Old 10-01-2007, 07:42 PM   #34
perrin247
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Im in the middle of a 35R and would really love to see one of these manifolds while my motors out of the car.
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Old 10-01-2007, 08:15 PM   #35
shvrdavid
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Quote:
Originally Posted by subaru5614 View Post
so am i now,i know how much room there is and have one i made with longer runners and larger plenum i ll be installing on a customers car soon
i hope the original poster has good luck if he chooses to persue this venture i ve been ask to make a few of by different people but i m in the middle of my subie build at this time so i don t have much spare time

looking forward to seeing his style
Why did you choose to run longer runners... Just curious....
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Old 10-01-2007, 10:07 PM   #36
STiBottom
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I am guessing to reduce lag from a larger turbo. With a boosted car it is a little less important cause the manifold reaches its pressure quicker but at the same time longer runners move the torque curve to the left.
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Old 10-02-2007, 09:36 PM   #37
Vmiz
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Quote:
Originally Posted by STiBottom View Post
I am guessing to reduce lag from a larger turbo. With a boosted car it is a little less important cause the manifold reaches its pressure quicker but at the same time longer runners move the torque curve to the left.
yes exactly wanted a lower power curve with the twin turbo setup on keinans car just didn t want the typical all up top power band
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