Andrew & Tamra's 818SR EM Autox Hybrid Destroked Long-Rod Build

[Hindsight]

This is my first season doing national level events, so perhaps I'm overly excited about everything

I wouldn't say that at all..... competing in anything at the national level is quite an accomplishment. Good luck and keep us posted!

[Tamra]

Successful weekend. Andrew and Tim are qualified for nationals, and I took 2nd in my class (only .025 from first!), which qualifies me and also gives me a chance at the overall if I do well at Nat's.

Also got to meet Bob and his son Michael and talk 818 strategy. They have some pretty cool ideas and I'm excited to see how they go.

[Bob_n_Cincy]

Successful weekend. Andrew and Tim are qualified for nationals, and I took 2nd in my class (only .025 from first!), which qualifies me and also gives me a chance at the overall if I do well at Nat's.

Also got to meet Bob and his son Michael and talk 818 strategy. They have some pretty cool ideas and I'm excited to see how they go.

congratulation on your qualifications.
Great to meet you guys in person.
Bob and Mike

[Tamra]

Here's one of my favorite runs from the Pro last weekend. It didn't count for a time because I red lighted, but I still really enjoyed this run since I went all out, knowing I had nothing to lose. I need to drive like this when I do have something on the line.



Sneak preview of fun things to come with the 818...

[Tamra]

Do I spy.... vents?



Do I spy... a relocated Cobb intake that will soon have ducting?

[metros]

More pics of your side vents?

Those pictures really show how much space there is over there. May reroute my intake over there.

[RM1SepEx]

Tamra, you really want/need these

P1120686.JPG

[Tamra]

Metros, I'll get some more shots this evening for you.

Dan, are those Mechie's? If so we are planning to place an order for a bunch of his vents after we perform airflow testing.

We are going to use the manometer I posted in the previous post to perform some airflow testing on the car. It should give us data for where vents need to be, if vents are pulling air in or out, and how effectively the vents are working. We also have some thermocouples on the way so we can measure relative air temperatures in different zones of the car.

[Tamra]

Stock Subaru vs... Non-Stock Subaru?

[305mouse]

looks just like my Outback. I'll save you the trouble, it's a lot slower, lol.

[Hindsight]

Question for you.... how did you route your AWIC coolant lines from front to rear? I looked through some of your older pics but couldn't see anything.

I have been planning on routing one down each side of the car. Now that I'm laying the hose out and test fitting everything though, it is a very tight fit where the flexible metal coolant pipe goes through the front firewall at the lower sides. There is just enough room for the 3/4" heater hose to fit along side the coolant pipe it but it is in full contact and I'm concerned about heat transfer between the engine coolant pipes and the AWIC rubber lines. I don't know that heat sleeving would even help much. I thought about running them down the center tunnel instead.

[Tamra]

Hey Metros, I didn't forget about you. I snapped some photos of the intake area tonight.










Also, we went ahead and ordered a new fuel pump. The Walbro you sent us (thank you again) unfortunately had a cracked fuel outlet. It wasn't visible until we pulled the rubber hose off, but the hose had some weird crimping thing in it that crushed the plastic on the pump. We decided it wasn't worth the risk and picked up a DW300 that is due this week.


Hindsight, we routed the feed and return line for the AWIC on the passenger side of the car, running right along side the feed line for the radiator. So far we have not experienced any problems with heat soaking the AWIC coolant. However, our AWIC coolant temp gauge starts at 100 degrees, which is not very valuable information (although we have never seen it go over 100, which is an indication that we aren't getting too much heat soak). We have a new gauge we are installing in the next week or two that will show down to 60 degrees.

[metros]

Sorry to hear about the fuel pump. Glad I didn't sell it to someone on NASIOC.

Thanks for the extra pictures.

[Tamra]

Sorry to hear about the fuel pump. Glad I didn't sell it to someone on NASIOC.

Thanks for the extra pictures.

It was really nice of you to send it to us - thank you again. Let me know if you need any additional photos.

I started mocking up some air ducting with cardboard tonight. The idea will be to block the filter from sucking in the hot air from near the turbo, and also direct the cold air entering the side vent to pass over the filter. It won't be fully air tight but hopefully it will help. We may also end up cutting the side vent significantly larger, but we are waiting to do some testing first - hopefully this weekend!

[Hindsight]

Thanks for the pics Tamra. Maybe I'm worrying about nothing on the heat soak.

[C.Plavan]

Just an FYI- I tried that location for the intake. It got too hot unfortunately. Maybe you will have better luck if you surround it.

[Tamra]

Thanks for the heads up, Chad. We will put some thermocouples around the air filter and see what we are getting while driving.

Hindsight, we should have more precise data soon that we can share, but the best I can say now is that after 60 minutes of autocross runs (actual run time) spread over a few hours, our gauge never left its pegged out location, meaning the awic coolant never exceeded 100 degrees. That included quite a bit of time idling in grid, which should have made it worse due to no airflow.

[Tamra]

We replaced the fuel pump last night. That is NOT a fun job in the car. You can't fully access it from the engine bay, so we ended up cutting an access hole in the firewall. Our seats are a real pain to remove, so we wanted to avoid removing them and the firewall if possible.

It looked like the old one had a very very small leak, just based on some griminess.

It is not an easy task to get tools in that location to spin the plate free, but we eventually got the old one out using a 3' long 3/8 ratchet extension, the cup end, to hammer the ring free. We spent a very long time trying to get the new pump in. The larger sock made things difficult (had to bend it while forcing it through the hole), and then the sock was hitting the bottom of the tank before the pump was all the way in (bigger sock than before), so we had to twist the shape to the side a bit. We can't tell if the sock is even still in the small baffle area, not that the baffles do much anyway. We ended up ditching the rubber gasket and siliconed it down thoroughly, which should get rid of our leaking problem.

Overall, what a pain. I'm looking forward to our winter install of a front mounted fuel cell.

Next up: install air box surround. I'm using plasticore for initial testing at least. Anyone see a problem with this? I don't think it gets too hot in that space.

After that: Make front splitter and rear ducktail. We are thinking alumacore for the front splitter, maybe lexan for the rear ducktail, but still still need to do some more research. Anyone have any good ideas or sources for materials?

[RM1SepEx]

I did the same fuel pump job with the inside firewall removed and had almost the same issues. It's a real PITA... I think that the gasket is weeping at my fuel level sender too, I HATE the stock FFR tank

[Hindsight]

Next up: install air box surround. I'm using plasticore for initial testing at least. Anyone see a problem with this? I don't think it gets too hot in that space.

If you box the filter off in that location, I'd bet money that it will work and draw cool air in. You should use one of those profiler tools to get the contour perfect against the inside of the fender. I see no issues with plasticore as a mock up. I'd consider adding some heat reflection tape on the engine side of it though. What you are doing is exactly what I plan on doing as well (next year when the body is on lol).

[C.Plavan]

This is the location I tried without luck. I didn't want to bother enclosing it, so I just moved it to fresh air into the passenger compartment.



(Great for me since I dont have passengers )

[Tamra]

Hindsight, what would you use for final material?

I doubt it needs to be air tight, since the purpose is to generally direct the air to the filter. Even if it's not perfectly air tight I'm sure it will help a lot! It's a PITA to work in that area as the cross braces and suspension parts are all over the place. Thankfully the plasticore bends so I can get it mostly into place, but my current mock up still has some gaps. I'll work a little harder to close them. We will work on it tonight and test this weekend.

Dan, are you planning to stick with the FFR tank?

[Tamra]

Chad, we will keep our fingers crossed that boxing it off and possibly opening up the side vent more will work. I don't think our passengers would appreciate it in their ears Also, with us having a windshield we don't actually get much airflow where you put yours.

The other option is the same location on the other side of the car. It seems like it might be cooler there. Do you know if your issue was lack of airflow coming through the vent, or heat from the engine bay?

[xxguitarist]

We also have a sheet of white ABS on order, to thermoform an additional exterior scoop for airflow, just need to pick up a cone of the same shape as an autox one to make sure it won't hit it when the rest of the car wouldn't have!

[Hindsight]

Hindsight, what would you use for final material? I doubt it needs to be air tight, since the purpose is to generally direct the air to the filter. Even if it's not perfectly air tight I'm sure it will help a lot!

I'd probably use some aluminum sheet (.063 or whatever the size is for the interior panels). I'd duct tape the mockup together (cardboard or plasticore) and if all was well, would trace that out onto the aluminum and cut it out with a cordless jig saw. I can't tell you how many metal things I have cut with my dewalt cordless jigsaw and a metal-cutting blade. Thick steel, aluminum... all sorts of stuff and it is easy to cut compound curves and straight lines. I'd probably weld the aluminum panels together... even if it's just partial welds. I agree on it not needing to be perfectly sealed.

When you ran your AWIC lines, did you match them to the radiator lines (IE hot on the passenger side and cool on the driver side)? Unfortunately with my setup (degas tank for the AWIC allowing it to auto-bleed) I have to go the other way.

[Tamra]

Both of our AWIC lines are on the passenger side for weight balance, so no hot-cold match up.

The only problem I can see with your plan is the assumption that you can put things in without bending them. I'm currently having to twist and contort the plasticore to get it into all of the locations, and then let it spring back flat once it's in place. Then, bend it again to "seal" things. Aluminum is flexy, but not as flexy as the plasticore. We would have to use a ton of small aluminum pieces in order to get it all in there. The area is a real pain to work in. I'm hoping the area is cool enough to use the plasticore for driving around, which would require riveting it on. What do you think?

[C.Plavan]

Chad, we will keep our fingers crossed that boxing it off and possibly opening up the side vent more will work. I don't think our passengers would appreciate it in their ears Also, with us having a windshield we don't actually get much airflow where you put yours.

The other option is the same location on the other side of the car. It seems like it might be cooler there. Do you know if your issue was lack of airflow coming through the vent, or heat from the engine bay?

I think the radiant heat was getting to it. The header and motor are not too far away, and I have found air circulation to be difficult (thats why I have all the vents now). I put it low hoping the heat rising would not effect it. It did. I could see high intake temps on the Accessport even moving.

[RM1SepEx]

Tamra, Long term I don't see using the FFR fuel tank, just not sure what will work "best" I'd really like a two part tank, a portion in the center tunnel, the rest in front like Bob's. I despise the fuel level sensor location, who makes a tank with that shape and it can't measure a large portion of the fuel load by design!

My air filter is in a similar area, behind my AAIC, I'm going to duct air to it using .050 aluminum with the duct taking advantage of the area over the AAIC. I may add some ducted air from the right IC vent in the engine cover too

[matteo92065]

I semi-strongly recommend you insulate the AWIC lines when they are aluminum and next to the aluminum engine water lines. I took IR pictures of my car after driving and that whole area gets really warm/hot and has very little air flow. The water going through that area is 180F. Your feet & lower legs will feel the heat coming through the sheetmetal from the water lines. You can put your hands on the lower exterior of the car and feel how warm the fiberglass gets.

Its cheap and easy to do now. Insulate and separate by 2"

[Hindsight]

Hmm, I didn't know it was that hard to get to. I would probably partially unbolt the side sail, enough to pull it 10" or so away from the frame in the back, and then add the box. I'd probably glue it to the body instead of rivet since I wouldn't want rivets going all the way through to the other side. The other option would be to glue a short base to the fiberglass that you could then rivet the box to but that would be a pain. I say glue the box in and if you decide to get rid of it, just cut it out with a die grinder leaving behind some remnants of it.... doesn't really matter.

RE using the plasticore permanently.... I agree with CPlavan in that I'd worry about radiant heat in that area. Turbo, header, up-pipe. I'd be afraid that stuff would melt. Might hold up if you glued some reflective + insulative covering to it (like the DEI stuff that has a reflective layer + a thin layer of fiberglass batting followed by an adhesive... I used it on my rear firewall).

[Tamra]

Once we have data to show if our AWIC lines are experiencing heat soak, we will definitely consider that. As of this point, we have not had the coolant heat up over 100 (minimum reading on our gauge), so not MUCH heat soak is occurring.

I agree that it seems like a good idea, but with our body already on, we will see if it seems necessary before going through the effort. I think your recommendation is good for others that don't already have the body on yet... and we will be the guinea pigs to see if it's really needed!

Our new water temp gauge should give a more accurate reading of exactly what our AWIC coolant temp is, down to 60 degrees, so we will be able to watch as it heats up.

[xxguitarist]

Our AWIC lines are not in direct (conductive) contact aluminum on aluminum with the engine coolant lines. They are spaced off by two rubber hose thicknesses, so we'd be relying on convection and (air) conduction, not aluminum|aluminum conduction. Both would be easy enough to fix by adding a small vent in the passenger side skirt area, inlet & outlet. Insulation wouldn't hurt, but it wouldn't have huge advantages in a stagnant area either.

[Hindsight]

How did you get the rubber AWIC lines to fit through the small opening in the FRONT firewall (behind the front tire) without directly contacting the flexible steel tubing that carries the coolant through there? I do see that you are using aluminum tubes on the side for both the AWIC lines but in front of that, it changes to rubber for routing through the little tunnel that goes into the front area of the car. On mine, there is no way to provide space in the tunnel between the radiator and awic hoses; it's just too small of an area (and that's with just one metal radiator hose and one 3/4" heater hose per side).

[Tamra]

Hmm, I didn't know it was that hard to get to. I would probably partially unbolt the side sail, enough to pull it 10" or so away from the frame in the back, and then add the box. I'd probably glue it to the body instead of rivet since I wouldn't want rivets going all the way through to the other side. The other option would be to glue a short base to the fiberglass that you could then rivet the box to but that would be a pain. I say glue the box in and if you decide to get rid of it, just cut it out with a die grinder leaving behind some remnants of it.... doesn't really matter.

RE using the plasticore permanently.... I agree with CPlavan in that I'd worry about radiant heat in that area. Turbo, header, up-pipe. I'd be afraid that stuff would melt. Might hold up if you glued some reflective + insulative covering to it (like the DEI stuff that has a reflective layer + a thin layer of fiberglass batting followed by an adhesive... I used it on my rear firewall).

I don't think fiberglass can hold up to much more heat than plasticore does, so if the plasticore melts then I think we have bigger concerns, involving our body panels. We will keep a close eye on it though. It's pretty far away from the header/upipe - at least a foot or more I would say. At least if it melts, nothing disastrous is going to happen.

As for the rivets, they'll only be on the interior stuff, not showing to the exterior, and the plasticore will just be wedged to the outer panels at an angle to hold it into place, not requiring rivets. The glue idea is a good one though.

[Tamra]

How did you get the rubber AWIC lines to fit through the small opening in the FRONT firewall (behind the front tire) without directly contacting the flexible steel tubing that carries the coolant through there? I do see that you are using aluminum tubes on the side for both the AWIC lines but in front of that, it changes to rubber for routing through the little tunnel that goes into the front area of the car. On mine, there is no way to provide space in the tunnel between the radiator and awic hoses; it's just too small of an area (and that's with just one metal radiator hose and one 3/4" heater hose per side).

they touch there for a few inches, which we aren't very concerned about.

[Oppenheimer]

I expect that the vent area is more than large enough to satisfy the requirements of the intake even at redline. Ramair isn't really effective, and especially not at autocross speeds. So no real need for adding a scoop to the side intake. So long as there is a box, sealed well enough so the intake sucks outside air from the vent, and not hot air from the engine compartment, and the box is decently insulated, I think you will be good.

I also expect that the plasticore will be fine, if you add a reflective insulating material. Even something like this Home Depot stuff:

http://www.homedepot.com/p/Reflectix...6025/100012574

Tape the seams with some foil tape like this, and you will also help further air seal it:

http://www.homedepot.com/p/Nashua-Ta...7792/100030120

[Tamra]

Thank you! I hadn't thought about the hvac tape. We have some of that already, actually - I'll use it! The reflective insulating material is also a good idea.

[Tamra]

Well, we have a boxed in air filter. It's not pretty, but it's fairly air tight thanks to Oppenheimer's idea of the HVAC tape. I stuck it everywhere.








And after these photos were taken, I also riveted on a top and stuck some more HVAC tape on it for good measure.

Our Forge BPV springs came in tonight, so we replaced the existing one. Surprisingly, it already had the blue spring, which is the 23-30 psi spring. We wouldn't have expected it to be leaking while driving around at 2-3k rpms... but regardless, we replaced it with the brand new blue spring. We will see how it goes when we drive it tomorrow. We have checked, and the air is definitely getting past the spring area because you can feel it coming out of the vent port.

[Hindsight]

Wow, bigger than I would have imagined. The way I was thinking of it in my head is that it wouldn't even touch the frame. It would be a very small box, barely bigger than the air filter, and would enclose 50% to 100% of the side scoop opening. But there are many ways to skin a cat! Keep us posted on the temps. I bet it works great!

[Tamra]

The thermocouples said ambient was 76, air filter box was 81, and engine bay was 98, while cruising at around 45mph. Pre inter cooler gauge temp read 110 and post read 90.