John's EZ36R H6 818R Build

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Originally Posted by Bob_n_Cincy

Hobby
I like the short trans mount. It cures the problem of the trans not being flat.
What about moving the whole engine back an inch or so?
Bob

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I decided against that because I wanted to be able to swap the 5MT for a 6 speed if needed down the road and the 6 speeds are already tight to the rear body work. Moving the whole assemble back an inch would make the 6 speed stick out the back. Also, it would put more stress on the CV joints as they are already angled back, another inch might be too much.

With my stiff Group N motor mounts, stiff trans mount and the front snubber I installed, there should not be much engine movement at all, I hope!

This a long post, I know, but let me know your thoughts on my design.

By choosing not to go with the Subaru H4 engine you take on a bunch of fabricating you would not otherwise need to do. The exhaust is one of the biggest in my view. There are no headers or kits available that will bolt on and work. You need to fabricate the entire exhaust from scratch. As I have never done an exhaust system before there was a fair amount of research involved. I ended up drawing up my exhaust using a 3D cad program so I could experiment with positioning and layout before I even started cutting metal.

I had a few criteria in mind before starting:

• Get the exhaust out as quickly as possible to reduce heat build up in the engine compartment
• Design it so it can be easily built
• Use off the shelf tubing and bends so it does not cost a fortune
• Make equal length primary tubes
• Try not to screw up the cars aero

Below are my ideas and a short pro/con list for each.

1. Run a side exit exhaust that would dump out just in front of the rear tires.
   
   Pros: Short exhaust run; fairly straight exit path (easy to build)
   Cons: Not much room given my cooling and oiling system (see previous posts)
2. The traditional "out the back" idea.
   
   Pros: Nice looking; exits in a known low pressure area
   Cons: Longest path (most heat transfer to engine bay); most costly; most difficult to build given the space constraints
3. Straight Out the bottom of the car.
   
   Pros: Shortest possible path (least heat transfer to engine bay); easiest and cheapest to build
   Cons: Screws up the under car aero; its so short the wide band O2 sensors would not read accurately
4. Out the top through the humps?
   
   Pros: Short exhaust path; easily fabricated; different and unique
   Cons: ?

After much debate and mock fit ups I decided to route the exhaust vertically out the top of the car through the engine double humps. I know what your thinking, that will look like a Peterbuilt truck! I thought the same thing at first, but think of the Porsche 918. Pretty slick I think.
Attachment 71815

Now hide those pipes behind a set of Mechie Hump vents and you have a very cool exhaust (pun intended). Hidden design, short length, good impact on aero, easy to fabricate. I have my winner! To ensure the exhaust exits and does not swirl about in the engine bay, I will build boxes under the hump vents that will seal against each exhaust pipe.
Attachment 71817

Here are some 3D CAD drawings of my exhaust design with the key frame rails inserted to ensure fitment.
The yellow rectangle represents the header flange, the redish orange cylinder is the rear top trailing arm (the one with heim joints supplied with the kit)

Isometric view from the back corner, just in front of the passenger rear tire:
http://thefactoryfiveforum.com/attac...1&d=1501901606

View looking straight down from the passenger hump:
http://thefactoryfiveforum.com/attac...0&d=1501901600

I am really sorry, but I recommend you evaluate the airflow first. I have cut out the humps for the vents on my car. The fumes from the engine come right out into the cockpit. I can only guess that air circulates and swirls into the back of your head.

It is sometimes overwhelming, I can't image what it will be like getting direct exhaust fumes into the cockpit area. It may asphyxiate you.

I also saw some of the first 918s, as they were driving through Denver for high altitude testing years ago. The ones that were still uncovered at the Marriott all the drivers were staying at had black soot on their deck lids. Maybe it is something they fixed, but I am guessing it will be a problem for sure on the 818.

I am not saying it can't be done, but I strongly advise you to be careful. The last thing you would want is to pass out while driving.

Remember he's has a R. So no windshield . I'm wondering if your using a muffler of some sort. Not much room except for a glass pack if that I would think . I'm liking the idea, I'll be doing my exhaust soon enough. I love this thread, so many great ideas. :cool:

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Originally Posted by bbjones121

I am really sorry, but I recommend you evaluate the airflow first. I have cut out the humps for the vents on my car. The fumes from the engine come right out into the cockpit. I can only guess that air circulates and swirls into the back of your head.

It is sometimes overwhelming, I can't image what it will be like getting direct exhaust fumes into the cockpit area. It may asphyxiate you.

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Remember I am building an 818R so no windscreen and decent airflow over the rear deck, at least compared to the 818s.

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Originally Posted by bbjones121

I also saw some of the first 918s, as they were driving through Denver for high altitude testing years ago. The ones that were still uncovered at the Marriott all the drivers were staying at had black soot on their deck lids. Maybe it is something they fixed, but I am guessing it will be a problem for sure on the 818.

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I figured that might be an issue. I will most likely paint the humps black to minimize any sooty appearance between washes. I imagine that is why Porsche has those blacked out tray inserts around the exhaust exits as well.

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Originally Posted by bbjones121

I am not saying it can't be done, but I strongly advise you to be careful. The last thing you would want is to pass out while driving.

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I have thought about this extensively and will definitely keep an keep eye on this during testing. I plan on using wool tufts attached to the body to double check for proper air flow direction. Thank you for pointing this out though, for those building an 818S this would be a bad idea!

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Originally Posted by flynntuna

Remember he's has a R. So no windshield . I'm wondering if your using a muffler of some sort. Not much room except for a glass pack if that I would think . I'm liking the idea, I'll be doing my exhaust soon enough. I love this thread, so many great ideas. :cool:

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You are right, no mufflers or cats :cool:. There would be room for a muffler in the vertical section at the end, its about 15" long, if I needed one.



And there is a backup plan. Should the vertical exhaust exit prove to exhibit back flow or be too messy, I can turn the pipes rearward just before they angle into the humps and exit them out the rear of the car. This keeps the manifold and collector section intact and (the hardest part to fabricate). I would only have to discard the two small sections of pipe after the flat merge collector and fabricate the relatively straight new sections needed to exit the rear of the car.

I have begun work to fabricate my custom headers. I have all the primary tubes, bends, and flat merge collectors as well as the header flange plates ready. Just waiting to build up the courage to light up the TIG welder and assemble the manifold sections :p.

http://thefactoryfiveforum.com/attac...9&d=1501712942

Such a cool build! I can't wait to see it on the track. Any idea how much WHP you'll be making?

As for the exhaust, If you are NOT running a windshield (which I'm assuming you aren't since you have an R), then I don't think you are going to get fumes in the cabin. It's the low-pressure created by the windshield that causes the exhaust to be pulled forward into the cabin. It is, however, going to be very loud! But I'm sure that H6 will make beautiful music.

Sorry, you should be good with the R. I look forward to seeing it when it is done.

It was late last night and I got worried for you...

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Originally Posted by Hindsight

Such a cool build! I can't wait to see it on the track. Any idea how much WHP you'll be making?

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Thanks for the support. I will be using the EZ36R in stock trim to start out with, so 254 hp and 247 lb ft of torque at the crank. After I get the whole car sorted I plan on going with forced induction, a centrifugal supercharger I think. Planning on low boost ~7 psi, should make about 375 hp and be fairly reliable (I hope).

'looks great! Thanks for all of your posts and pic's. Great inspiration & ideas.
I wish I had jacked-up my H6 as much as you (I'm at ~+3/8"). I don't like the pan hang either and it would have given me that much more room for my header routing.
Looking forward to your exhaust build, please keep posting. I've got a box of bends an have been noodling that project.
*Also great work on your shifter conversion!

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Originally Posted by DSR-3

'looks great! Thanks for all of your posts and pic's. Great inspiration & ideas.
I wish I had jacked-up my H6 as much as you (I'm at ~+3/8"). I don't like the pan hang either and it would have given me that much more room for my header routing.
Looking forward to your exhaust build, please keep posting. I've got a box of bends an have been noodling that project.
*Also great work on your shifter conversion!

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Its not too late to jack the motor up! Its far easier now then trying to retrofit later.

I love the shifter mod, super smooth and positive shifts, which is unusual for a cable shifted unit.

Your build is looking great!! That thing will be LOUD with no mufflers, also some tracks require mufflers, even if it passes the sound level test.

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Originally Posted by DanielsDM

Your build is looking great!! That thing will be LOUD with no mufflers, also some tracks require mufflers, even if it passes the sound level test.

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Not as loud as my FFR Roaster that has a 347 cubic inch V8 with no mufflers!
All the tracks I attend do not have sound limits and with ear plugs and my helmet, almost any motor is quiet ;).

What size tubing are you using ? From the pictures it looks like 2" going into the collector and 4" out. The cad drawings prospective are from the passenger side looking back, right? I spent some time looking at my car trying to see how it will work. Have you worked out how the suspension will work through its range around it? It seems that there is little room for error.

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Originally Posted by flynntuna

What size tubing are you using ? From the pictures it looks like 2" going into the collector and 4" out. The cad drawings prospective are from the passenger side looking back, right? I spent some time looking at my car trying to see how it will work. Have you worked out how the suspension will work through its range around it? It seems that there is little room for error.

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The tubing sizes are as follows. Primaries are 1.5". The three primaries come together in the flat merge collector and exit to a cone that starts out as 2" and expands to 2.25". The rest of the pipe is all 2.25". You are correct on the perspective, passenger side looking back from the rear firewall.

I spent a huge amount of time working out this design. Full suspension travel was taken into account, as well as the inner fender splash guard. It does look close, but it actually has more room than if you tried to run the collector on the inside of the frame.

This video may help visualize. It is the section from the head to the collector with planes inserted for the inner fender and cylinder head.

https://www.youtube.com/watch?v=fwOB...ature=youtu.be

where did you source your header flange and collector and the pourable polyurethane for the mount thanks sam

Wow! That video is so helpful than you !

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Originally Posted by Samiam1017

where did you source your header flange and collector and the pourable polyurethane for the mount thanks sam

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Here's one source, I googled it can't vouch for it though.
http://www.spdexhaust.com/ImportB.html#

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Originally Posted by Samiam1017

where did you source your header flange and collector and the pourable polyurethane for the mount thanks sam

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The flange came with the motor but flyntuna is correct on the source for that.
http://www.spdexhaust.com/ImportB.html#

The collector I got here.
http://coneeng.com/collectors.html

The liquid urethane I got here.
http://www.suspension.com/diymmi

http://thefactoryfiveforum.com/attac...4&d=1502142603

I completed the oiling system today. I removed the small factory oil to water cooler and added a take off plate so I could route the oil to my external filter. From the filter the oil goes through a much larger oil to water cooler and then it passes through a one way check valve on its way to both the Accusump oil accumulator and finally the engine. It turned out nice and compact

Attachment 71946 Attachment 71947

Looks great,
Are you going to have a way to measure/adjust the air side of the accusump without tacking off the side sail?
Bob

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Originally Posted by Bob_n_Cincy

Looks great,
Are you going to have a way to measure/adjust the air side of the accusump without tacking off the side sail?
Bob

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No, if I need to change it I will have to remove the side panel. But, all the panels are attached with rivnuts so it would be possible. I have never had to change the pre-charge on the Accusump in previous installs, so I do not think I will need to this time either.

Hmm... now that you brought it up, maybe I'll drill a hole in the side panel to access the valve on the back of the Accusump. This way I would only have to remove the door to adjust it.

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Originally Posted by Hobby Racer

Hmm... now that you brought it up, maybe I'll drill a hole in the side panel to access the valve on the back of the Accusump. This way I would only have to remove the door to adjust it.

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I would run a piece of brake line to a remote schrader valve with a viewable gauge. We checked ours whenever we checked the oil between each run.
Bob

Any chance that the way the coolant return line "http://thefactoryfiveforum.com/attachment.php?attachmentid=71947&d=1502142856" as you installed it, may result in an air pocket? Not sure if with an air pocket it would make much of a difference though. As pointed out in other threads, the main function of the Oil Water heat exchange is mainly to heat the oil on cold days.

I am not going with the OEM return-less fuel setup that Subaru uses, but instead I am using a return system with an external fuel pressure regulator. This of course means the stock rails will need to be modified as they dead end and have no way of returning fuel to the regulator.

Here is the stock rail and a pic of the dead end that needs to be modified.
Attachment 72704 Attachment 72708

Drilled out the end and ground it smooth.
Attachment 72707

Next, grind down a pair of -6AN to NPT fittings that will be welded to the end of the rails to allow fuel to return to the pressure regulator. Here is one being test fitted.
Attachment 72706

The finished rail, welded and ground down.
Attachment 72705

What I lack in welding skill, I make up for in grinding patience ;)

Are you going with a return system to insure fuel pressure under race conditions? Do you see any reason not to keep it return less, I mean Subaru had a reason to use that system right? My car will primarily be a street car, and I don't think I'll be adding any major power adders like a supercharger or turbo. Is your choice of ECU a factor in the decision? I'm a little confused. :p

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Originally Posted by flynntuna

Are you going with a return system to insure fuel pressure under race conditions? Do you see any reason not to keep it return less, I mean Subaru had a reason to use that system right? My car will primarily be a street car, and I don't think I'll be adding any major power adders like a supercharger or turbo. Is your choice of ECU a factor in the decision? I'm a little confused. :p

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I am using a MegaSquirt 3 Pro aftermarket ecu. It is much simpler to use a return type system than to try and get the factory setup to work with the aftermarket ecu.

And yes, using an Aeromotive fuel pressure regulator.

thanks. When did megasquirt make an ECU available for the ez36? I heard a year or two ago they were looking into it. I was considering using the Haltec because a buddy is a dealer, but more tuners around here are proficient with megasquirt .

Also, your two into one coolant line looks to have a bend were the bung is, did you heat the pipe to bend it?

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Originally Posted by flynntuna

thanks. When did megasquirt make an ECU available for the ez36? I heard a year or two ago they were looking into it. I was considering using the Haltec because a buddy is a dealer, but more tuners around here are proficient with megasquirt .

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MS3-Pro ecu is a universal standalone and can be configured to run almost any engine. In particular, they have a cam/crank trigger for the Subaru 36-2-2-2 crank wheel which is used by the ez36r. It can also control the 4 VVT cams so its a nice fit. You do need to splice it into the factory harness though, it is not plug and play.

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Originally Posted by flynntuna

Also, your two into one coolant line looks to have a bend were the bung is, did you heat the pipe to bend it?

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I used the FFR pre-bent tube for that section! Worked great for what I needed.

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Originally Posted by Hobby Racer

And yes, using an Aeromotive fuel pressure regulator.

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Which one are you using? The Aeromotive 13109 has a return fitting built into the regulator.

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Originally Posted by STiPWRD

Which one are you using? The Aeromotive 13109 has a return fitting built into the radiator.

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I am using Aeromotive 13129, very similiar, just a slightly different pressure range.

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Originally Posted by Hobby Racer

I am using Aeromotive 13129, very similiar, just a slightly different pressure range.

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That one has a return line as well. Just curious, but why modify the rails when you could use the return line off the FPR?

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Originally Posted by STiPWRD

That one has a return line as well. Just curious, but why modify the rails when you could use the return line off the FPR?

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It is possible to run the regulator in that way but they are most efficient when run on the return side of the fuel system. This way fuel flows through the rail constantly and the pressure is more precisely regulated. That is why they have two inlet ports and one outlet port. Each rail feeds into a separate inlet port and the excess fuel is returned to the tank via the single outlet port.

http://thefactoryfiveforum.com/attac...7&d=1503494761

Good to know, thanks

how did your poured tran mount turn out?

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Originally Posted by Samiam1017

how did your poured tran mount turn out?

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It came out excellent! I posted pics here in this post. See the last pic in the post, its on the left.

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Originally Posted by Hobby Racer

It came out excellent! I posted pics here in this post. See the last pic in the post, its on the left.

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thanks i dont know how i missed them

Well, I've been buttoning up a lot of small things in preparation for the engine's first start. One thing you might find useful is how I installed a transmission temperature sensor in the 5MT. Before fabricating up a whole transmission cooler / pump assembly I thought it wise to monitor the transmission temps to see if its really needed first. I believe that part of the 5MT's fragility is due to excessive temps and their effect on lubrication.

Anyway, there is no easy place to add a temperature sensor without tapping into the case. Instead I modified the drain plug to incorporate the temperature sensor. It fits beautifully and does not protrude below the diffuser.

http://thefactoryfiveforum.com/attac...2&d=1505357216

The sensor is a standard GM thermocouple used for coolant. I drilled out the female torx fitting and tapped it for 3/8" NPT. I ground flats on the sides so you can get a wrench on it now that the torx hole is gone. I also punched out the magnet on the bottom of the stock drain plug. Now I can monitor transmission temps and if needed add a cooler down the road.

Attachment 73636Attachment 73637Attachment 73635