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Anyone running aftermarket or custom intake manifold?

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I've been looking at the aftermarket Weber intake manifolds from Ram and Joe Souza Gyroplanes (scroll down) and have read about people (in the aviation community, mostly) making them. I'd like to know whether it is worth the expense or effort. Ram's is similar to the one on the linked frame but it is welded aluminum and might have a larger plenum. It is $350 without the carb or water system.

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Guest taprackready

Why could't some enterprising person make a copy of the ram intake but out of steel tubing like ehaust tubing? Seems like it would be easy to trace the bottom of a factory intake and cut out the flanges that bolt to the head, get some prebent mandrel tubing from summit and weld it together with a box center section to bolt on the carb.

 

Bill

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I have a factory dual carb manifold for an EA81 that I thought about having duplicated but I am very sure that would be extremely expensive. My brother has a friend who has a machine shop. Maybe I should ask him about it. I will not lend it out to anyone though. Too rare to have someone mess it up.

 

Dennisex24 and a few others are running the famed spider intake. I am curious who started the hype about the spider intake. I want proof of some sort showing a difference in performance. Is it worth the time/headache? Anyone know anything?

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That manifold doesn't look superior to a stock intake. It's just pipe and a flange for the carb. It may not work better for a street car. Remember, an airplane runs wide open. I also don't see any cooling or vacuum ports.

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Cooling ports on that manifold, are the brass looking things just above the mounting flange.

Vacuum ports can be added as needed. Off of the plenum for manifold vacuum.

Depending on carb used, you may have some there, but it will have the ported vacuum for the disty anyways.

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Dennis, When I get mine done we will compare even though you have some extra mods done plus I have an auto. I was actually lloking for numbers or specs, cold hard facts in black and white. I know where there is a spider intake and thought it would be good to throw on while we were already doing the work. I found the xt turbo at the same yard where we went, it was hidden pretty well. It's in pretty good shape too! Boz

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It would be interesting to get standard and a spider manifold on a flow bench.

 

Don't forget the rice factors:

 

Simply making a change adds horsepower (even decals will accomplish this).

 

If it looks better, it MUST be better (it's amazing how fast your car will go with colored vacuum lines)...LOL

 

BTW...I'm adding a spider to my RX:D

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Guest taprackready

is anybody running a custom intake on this board? What is a Spider intake and will it fit an EA81. Pictures?

 

Bill

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Dennis, Aren't you supposed to be at work right now???? ha ha Must be nice. Let me know if you wanna go grab it, I will call and see how much he wants, either that or we can pull it and I can set it aside for a dark and stormy night..........

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Originally posted by taprackready

Why could't some enterprising person make a copy of the ram intake but out of steel tubing like ehaust tubing? Seems like it would be easy to trace the bottom of a factory intake and cut out the flanges that bolt to the head, get some prebent mandrel tubing from summit and weld it together with a box center section to bolt on the carb. Bill

 

I've also read that people have fabricated the flanges and made runners out of mandrel bent exhaust tube. There are also instructions for fabricating a carbon fiber intake manifold HERE. I have neither the time nor inclination (a/k/a ability ;) ) to fabricate a metal intake. A composite one might be a fun project (with an extra high "rice factor" if I used carbon fiber ;) )

 

Seriously, I appreciate the "rice factor" discussed above, but doesn't a small increase in runner diameter equate to a larger increase in cross sectional area? I assume the ID of the Joe Souza and Ram runners must be larger than stock. They also lose the charge-warming cross section-reducing coolant passage.

 

P.S. Assuming the "spider intake" works better, can you put a Weber on it? Or is it fuel-injection only?

 

P.P.S. I deleted the Ram photo.

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Here' are some of the quotes about the stock manifold that got me thinking:

 

The problem with the EA81 manifold is that it has a water crossover for the two block halves. This makes modifying or replacing the manifold very difficult. The other drawback is the heating of the air by the hot manifold, cold and dense gives you more power. There are solutions to this although they are not cheap or easy. Some in the aviation community have made replacement manifolds out of carbon fiber with a water passage separate from the manifold. This is both lighter, better flowing and cooler. LINK 1

 

The intake manifold is replaced with a custom one with larger diameter runners and no coolant passages to heat the charge. I made mine from carbon etc........... deleted...... (see my article on carbon manifold construction....................

LINK 2

 

The intake manifold is replaced with a custom one with larger diameter runners and no coolant passages to heat the charge. This can be done in a variety of ways ranging from mating custom bent pipes to heavy-duty hoses all the up to fabricating an entire manifold from carbon fiber.LINK 3 (this one includes a photo of an engine with a custom intake manifold.)

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<<Dennis, Aren't you supposed to be at work right now???? ha ha Must be nice. Let me know if you wanna go grab it, I will call and see how much he wants, either that or we can pull it and I can set it aside for a dark and stormy night..........>>

 

Dennis doesn't need one, he has one already. I'm the one that needs one for my project.....maybe we can work something out.

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Originally posted by taprackready

is anybody running a custom intake on this board? What is a Spider intake and will it fit an EA81. Pictures?

 

It doesn't look like anyone is running a custom intake :(

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Xpert, I know Dennis has one. I was referring to myself. I have my EA82T out right now and figured we could do it all at the same time. If you have a need for it email me at cmakar@hotmail.com and we will talk. I am unemployed so right now it would just be an extra expense. Not a big deal to me. Let me know, maybe we could all meet up at my place go pull that spider and then turn some wrenches at my house for a while. Hmm, let's see, Me, You, Dennis, Hocrest, EJ, Mooseman, Kecksnext? Sounds like a small party to me, Plus I could show you a local area to go wheeling. Sort of like a mini PB. It's kinda cool. Let me know, Boz

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I belive that the maind difference in the operating theory behind the spyder and the single tube intake is that the spyder acts like a dual plane manifold and the standard acts like a single plane, which means that at low rpm there is less air to get moving so it will increase torque. depending on the size of the runners it can still flow good at high rpm but the down low, where you need it will be fatter.

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I just got an e-mail from Joe Souza. Here's what he says about his intake manifold:

 

The manifold is designed around the two barrel Weber carburerator, the intake runners are 25% larger in diameter than the cast aluminum intake manifold. The intake is designed for more low end torque.

 

It comes with an in-line thermostadt, it does not come with a carb, that is additional $275. The intake gasket and bolts are included along with carb base gasket and nuts.

 

he also said the manifold/carb combo is about the same height as a stock manifold and Redline Weber carb and adapter.

 

It looks like Joe's manifold orients the carb the same way as the Redline Weber conversion, which should make hooking up the linkage easiere. The ovel hole in the RAM intake is oriented side-to-side. The oval hole in Joe's is oriented fore-an-aft.

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I have plans for a wildly torquey ea82 turbo in preparation. I have a pair of heads and am fully intending on building a completely custom intake manifold to suit. If you have ever seen a EA manifold cut in half you would agree that they are crap. The diameter of the tube gets down to as low as 1/2" which is just unacceptable for making power. I intend on using 1" id aluminium tube for the manifold and completely separating the coolant flow from the intake, which will also gain power. Basically I want to be gaining peak torque at around 2000rpm or lower, this will make the car better offroad with 27" tyres. with a small turbo aimed at creating peak boost by 1500rpm - anyway, that's getting off track!!

 

Yes, build a new manifold - you will vastly improve the system!!

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The spider intake is a vast improvement over the straight intake because the straight intake necks down at the 90 into the head, were as the spider doesn't as much. Also what the main thing about the spider is that it points the throttle body in a direction where it is easier to plumb in an intercooler to it, without haveing to make a restrictive 90 from the intercooler to the throttle body as you would have to do with a straight intake. I'm not sure about the EA82 spider, but my ER27's spider has the water passage separate from the intake runners, so you don't get the heating of the intake charge.

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I live pretty close to Joe Souza. Next time I'm at my mom's house, I'll stop by his shop and check out the products. I thought that his and Ron's manifolds were worth considering.

 

But now I met a hot rod chevy dood who is interested in subarus, and knows all about souping stuff up and fabrication, so hopefully we'll figure somethin out.

 

Its good that your stirrin the pot, cuz alot of people stop chimin in when it comes to engine mods, but keep us posted on what you find, and i'll do the same.

 

with out the increased manifold flow, the decked heads with larger ports don't mean much, so its important that people modding an EA engine figure something out for the IM...

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Thanks StormTrooper. See if you can get Joe to tell you more about the differences in the dual-carb head and cam, will you please. He was very enthusiastic about them. He also builds or built racing cars and said that engine, his manifold and the other common ignition and exhaust mods would give me the best bang for the buck for my application (maximizing low-end torque while preserving reasonable highway driveability). The said the dual-carb heads breathe better stock than ported US Spec heads.

 

I'll be doing more research on that this week.

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Cool man, will do. When I refer to the widening of exhaust ports, and decking, I'm refering to the much cheaper modding of the single port heads. RAM sells the kit for the bigger springs, valves, and lifters. You just gotta send em the heads, and he'll work 'em for a decent price. The dual port would obviously be the way to go, but I don;t have that kinda dough...

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Originally posted by StormTrooper

When I refer to the widening of exhaust ports, and decking, I'm refering to the much cheaper modding of the single port heads.

 

I got the dual carb long-block and Joe's intake. Joe and Ron have bothe been real helpful. When I crack the dual-carb long-block, I'll clean up and maybe widen the ports. The dual-carb head is already decked, or so I am told. I'm tempted to go all-out, but my plans already blow the hell out of my budget for this car. I will probably just bolt on the Weber and Joe's intake, upgrade the ignition system and open up the exhaust from the y-pipe back.

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