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

[Aero STI]

I wish you had a build thread so we could see what your full setup is! Our AWIC should be fully burped. We also didn't have problems before the body was installed.

Yeah, it would be a little weird having a thread for a car that's nearly complete and I'm just working on bugs. I dunno.

Here is typical performance for my AWIC. It's a few degrees above ambient, I make a bunch of boost, the system recovers pretty quickly (11 seconds is shown in this graph). Ignore the "pre turbo", this is post turbo.



Also, that's after a few back to back 3rd gear pulls making 450 WHP and 500 WTQ. (Graph is truncated to 5200 RPM to remove the wheel spin that occurs around 5600 RPM)

[Hindsight]

Yeah, it would be a little weird having a thread for a car that's nearly complete and I'm just working on bugs. I dunno.

None of us would think it was weird! I too, would love to see your setup.

How do you like your implementation of the 7163? Does it blow the tires off in most gears or is it manageable? Is the ~4200RPM torque peak working out ok or do you wish it were lower?

[Tamra]

That looks like a great setup AeroSTI, and a ton of power! Ditto to Hindsight's questions.

I am surprised that the turbo falls off in boost so much after 4k though. Is that a 4-5psi drop from 4k-5k? I wouldn't think such a big turbo would have a hard time in the upper rpms like that.

What are you using to log your AWIC temperatures? I haven't seen anyone else have so much success. Only climbing 10 degrees over ambient in boost in incredible. Do you mind sharing more information on your AWIC setup?

[Aero STI]

Well if it's not weird I'll see what I can do. Probably better than mucking up other people's threads. I'm more of a forum reader than contributor these days.

The EFR is working great. The plot above is not the final tune, it's actually a lot of revisions away from final. I'm still working with Phatron of Phatbotti Tuning. The guy is responsible for tuning this 7163 powered car: http://forums.nasioc.com/forums/show....php?t=2720772.

I expect everything is going to move left by a few hundred RPM as AVCS and timing are optimized. There is more power in it as well, the boost taper is due to injectors being maxed out at 45 PSI base fuel pressure, I'm at 55 PSI now so 24 PSI to redline is attainable. This powerband is not for everyone. The car is a little nutty and definitely has traction issues. I'm pulling 1 G acceleration around 60 MPH. Lowest 50-80 MPH of 1.7 seconds, 60 to 80 of 1.06 seconds. I haven't done any pulls in 4th or above yet.

I don't think my AWIC setup is anything different than anyone else. My bosch pump is wired with my fuel pump to a 40 amp relay. I'll start a thread sometime in the next couple of days and document some things.

[Hindsight]

Nice! I'm looking forward to it. Do you have any type of limited slip or electronic traction control?

[Bob_n_Cincy]

What are you using to log your AWIC temperatures? I haven't seen anyone else have so much success. Only climbing 10 degrees over ambient in boost in incredible. Do you mind sharing more information on your AWIC setup?

Tamra
He was only in boost for 3 to 4 seconds and it raised 10 degrees.

Aero
I would also like to see more of your car. A lot of us are in the troubleshooting phase.
Join the party.
Bob

[Aero STI]

Bob, you're right, but that was also after 3 repetitive runs. The system dissipates heat pretty well. This was my attempt at getting things nice and hot idling. I sat for 10 minutes on the side of the road while I changed logging parameters, then started logging and drove around. A good deal of cruising 60 MPH or below, but plenty of stops too.

I do have 19mm phenolic spacers so my 2.5i intake manifold can clear the AVCS solenoids.

[Tamra]

Went to the tuner today. Good news and bad news.

Good news - we have a safe tune and a car we should be able to romp on all day.

Bad news - the car is hitting a wall at 16psi and a little over 300whp.

EFI is thinking that the AWIC is restricting the airflow somehow, and that we need to increase the size of our core.

Watching the tune, they bumped the boost up to over 20PSI and the car was still only making just over 300whp. The temps also started climbing and there was some detonation, so they backed it off. At 16psi the car is happy as can be and makes 300whp even on a super hot day (in the 90s) after doing 40+ pulls on the dyno. It is a little disappointing that our tune earlier this year in March showed better turbo spool and even a little more power, but then again it was a fairly cold day, and today was HOT, and the car was getting heat soaked.

So here's the graph:


A few photos for everyone:









The tune also encompassed tuning the rev limiter (starts to pull timing at 6900rpm-7400rpm - very smooth!) and two step. We can control the two step RPM using the Cobb.

Here's a video of the two step set at 3k (friendly for the neighbors )

[Hindsight]

I'm not a tuner, but IMHO I really don't think the intercooler is causing a power-robbing restriction.

You could put a boost gauge before and after the intercooler and see how much pressure drop there is. The core is spec'd to be like .5 psi pressure drop or less I think.

The other thing is that I'm pretty sure I have read at least three people exceeding 350HP with this exact same intercooler core. I believe Wayne has done it with a dominator 2.5, Metal Maker is around 330+ with a Dom 1.5 I think, and Aero STI is over 400 on ethanol. I'm pretty sure these three are running the same core you are but I could be remembering it wrong.

So there is power loss due to restriction, and power loss due to temps. Temps I could understand, restriction I'm skeptical. If the intake temps are getting too hot, that does obviously point to something in the intercooler system. You did a great job on the intake setup and testing so you know that's now the issue. Did EFI use a really big/strong fan that pushed enough air through the front heat exchanger? Do you see lower temps on the street at speed vs on the dyno? Didn't Wayne make a comment some time ago about doing multiple dyno runs while having the intake temp remain constant? Not sure what ambient temps he did his dyno pulls on though. What did your AWIC water temps look like?

[Tamra]

We are using a different core than others I have seen on the forum. It is a Frozenboost core, and it isn't giant by any means. The air also does a full 180 turn inside of the core. I like your idea of checking air pressure before and after the core - that would settle it for sure.

As for the fan set up, they had a mobile fan blowing directly into the side vent with the air filter. It was a fairly strong fan. The front GIANT fan is made for top mounts, so it definitely wasn't the best. I sprayed some water on the AWIC Radiator between pulls to try to help cool it down.

This combo kept the water temp around 95 between pulls and around 100 directly after. It was 90 ambient but it was pretty hot inside the dyno room. This is comparable to the street temperatures I saw while driving home - 90-95 degree water temp.

Between pulls we were seeing post intercooler temperatures of around 100-105. During pulls, up to 140 ish. I did not watch the gauges during every pull though.

I can see the heat causing some detonation at higher boost levels if things heated up further, however, I would have expected the car to make more than just over 300whp when it was relatively cool and pushing higher boost levels. It's weird how it hit such a wall.

We are leaving for Solo Nationals in the morning, so we won't be able to do any further testing for a few weeks.

[Hindsight]

If the water temps are staying low, which it sounds to me like they are (100 is not bad if ambient was 90), and you had 140 intake temps, this really points to a core that is too small to transfer enough of the intake charge heat into the water. It sounds like the front heat exchanger is working ok.

With regards to the 180 degree direction change, I wouldn't be too concerned about that. Think about a front mount WRX setup. LOTS of bends there (way more total degrees of bends than you have in your setup).

Back to your AWIC core: Is the core itself the same as most others are using (Type 14), but with the end tanks in a different orientation? Or do you also have a smaller core?

[Tamra]

Typing from the road here so sorry if my replies are shorter over the next week and a half. We are officially on the road to Lincoln!

It's a frozenboost type 3, which claims it is good for 600hp and less than .1 psi of pressure drop. http://www.frozenboost.com/air_water...air-p-203.html

They said they had another car at one point that did the same thing with an awic - just hit a hp wall. They swapped the core (not sure to what - could have been a2a) and made 100hp more before even tuning it, and more after the tune. Cooling wise, they highly recommended e85 for power, cooling, etc.

[Hindsight]

I am skeptical of their "HP wall with an AWIC statement." Again, I'm sure they know more than I do about tuning, but an AWIC isn't a magic black box and it can only restrict power in two ways that I'm aware of:
1. Not remove enough heat from the intake charge
2. Too much pressure drop

You know how to measure both so it should be pretty easy to see what's happening.

You are using a smaller core than most of us. Your actual core is 10" x 4.5" x 4.5". Most are using a core size of 10.5" x 6" x 4.5". Those core sizes don't include the end tanks. I'll admin the size isn't THAT much of a difference, but if you find you have more pressure drop than advertised, obviously you could address that with Frozenboost. If the pressure drop is good but you aren't able to transfer enough heat, then just move up to a larger core size.

I agree fully on e85 from everything I have heard and read. Runs cooler, can bump the timing much more aggressively, and you will get a lot more torque from it. Much safer at higher boost levels. On a car like yours that is mostly for track use, it would be a good option. For street, it obviously limits you to staying within range of an e85 station. I go back and forth on whether or not I want to run E85 or 93 octane pump.

Safe travels on your drive to Lincoln!

[matteo92065]

Typing from the road here so sorry if my replies are shorter over the next week and a half. We are officially on the road to Lincoln!

It's a frozenboost type 3, which claims it is good for 600hp and less than .1 psi of pressure drop. http://www.frozenboost.com/air_water...air-p-203.html

They said they had another car at one point that did the same thing with an awic - just hit a hp wall. They swapped the core (not sure to what - could have been a2a) and made 100hp more before even tuning it, and more after the tune. Cooling wise, they highly recommended e85 for power, cooling, etc.

Keep in mind that most of us are using the type 14 core and is listed as 10.5 x 6 x 4.5 or 283.5in^3. The type 3 core is listed as 10.5 x 4.5 x 4.5 or 212.6in^3.
33% more volume. Same frontal area, but more distance for cooling? Better cooling but more restriction?

[metalmaker12]

What bump steer kit do you use.

[metalmaker12]

Race gas and less timing also run cooler

[metalmaker12]

I like your wheels and mine the best on the 818

[Frank818]

Little late on the AWIC debate, but a too small core will definitely cause issues. Which issues, might depend, but increase in temps, certainly, cuz the core is too small so it can't handle the volume of air. I wouldn't be surprised as well if it would cause a restriction due to the fact it would be too small, but I don't know. What size inlet/outlet?

The thing is that they claim it's good for 600hp and you have half that. Weird... Unless their claim isn't true?

[bbjones121]

Air to air intercooler.

[Bob_n_Cincy]

Bad news - the car is hitting a wall at 16psi and a little over 300whp.

Watching the tune, they bumped the boost up to over 20PSI and the car was still only making just over 300whp. ]

I don't think the problem is restricted air flow in the AWIC.
They raised the boost to 20 PSI. The 20PSI pressure is measured after the AWIC by the MAP sensor.
Bob

[bbjones121]

What injectors do you have?

[Tamra]

My guess is that everything is related. If there is a boosted air restriction, although we may be getting 20psi to the engine, the turbo could be working extra hard to get there, causing more heat, causing the car to pull timing, etc.

When we get back we will test for restriction by checking boost before the inter cooler. We will also do some more research to make sure we aren't taking the turbo out of its efficiency zone, and then we will decide the next step on the AWIC core. For now at least, 300whp isn't boring, and we can safely go have fun with it

[Tamra]

What injectors do you have?

ID1000 injectors


I recently updated page 1 with our build specs for quick reference

[Tamra]

Back from Solo Nationals. I ended up taking 2nd for the season in L3 for the Pro Finale, and then ended up taking the National Championship for CSPL. What an amazing week! Andrew had a great time but had a rough day 1 which knocked him down a ways, but he moved up a ton of places on day 2. So goes it in a huge STR class!

Plan for this week is to finish up the front splitter on the 818, and start working on the rear ducktail support. We will need to weld in bracing, re-do our hood pins, make the ducktail, add support points, etc. Our goal is to get it out to autocross the weekend of the 26th.

Oh yeah, and Andrew drove the 818 to work today. Officially daily driver status now.

[Frank818]

Oh yeah, and Andrew drove the 818 to work today. Officially daily driver status now.

Yeah he got to do it and not you?

But seriously, no heat soak?

[Hindsight]

Woah congrats on your placements!!!!

[Tamra]

Yeah he got to do it and not you?

But seriously, no heat soak?

I got to drive it to the tuner a few weeks ago, which was 45 minutes each way. Seems like a fair trade

He said no problems, but it was cool this morning. Should be hotter on his way home so I'll update you later.

Woah congrats on your placements!!!!

Thank you! I'm still in a little bit of shock lol

[Mitch Wright]

Nice finishes great job and congratulations.

[Rasmus]

Congratulations on Solo Nationals!

[Tamra]

Thanks everyone

Finally worked on the car last night after a few days of recovery.

The ducktail support is finished. Next up will be the ducktail. The support bar also included new tabs for mounting the hood hinges, since we were previously using spacers with FFR's brackets, which felt very flimsy. It's now nice and sturdy (better be, since it's going to be taking a lot of downforce!)

[Scargo]

Will it be "NASCAR-like"?

[bbjones121]

Thanks everyone

Finally worked on the car last night after a few days of recovery.

The ducktail support is finished. Next up will be the ducktail. The support bar also included new tabs for mounting the hood hinges, since we were previously using spacers with FFR's brackets, which felt very flimsy. It's now nice and sturdy (better be, since it's going to be taking a lot of downforce!)

Looks great. This is what I was planning on doing as well. Way too flimsy back there. I do not want to be worrying about the body flying off at 100+ mph

[JeromeS13]

Looks great. This is what I was planning on doing as well. Way too flimsy back there. I do not want to be worrying about the body flying off at 100+ mph

It won't fly off as is. I've been up to 130 MPH or so.

[Tamra]

Will it be "NASCAR-like"?

Yes it will

Looks great. This is what I was planning on doing as well. Way too flimsy back there. I do not want to be worrying about the body flying off at 100+ mph

We aren't worried about the body flying off. However, we are worried that if we attached a 10" ducktail to the fiberglass, that it would break at higher speeds.


Also, we will have to redo some of the bracing. When we went to attach the bumper there was some interference, unfortunately. That will be a project on Sunday, along with installing coilovers on our miata (going light STS build) and engine mounts in the Speed3. Today, off to autocross!

[Tamra]

Bracing re-done, and e-mod legal ducktail designed, cut and installed!






It is held on by the hood pins, which are attached to the frame/bracing we welded on, and one rivnut into the trunk lid, making it easy to take on and off in minutes. It's hard to see in the photos but the upper bolt on the side plates has 3 adjustment holes for angle changes as well.

[Scargo]

Nice work! Now, with the bracing, the down-force will go straight to the suspension. Is that the max legal width and height for the ducktail?

Now you need this for the front!
13-Real-Hoopties-of-New-Jersey-24-Hours-of-LeMons-BS-Inspections.jpg

[Tamra]

It is not quite max legal width and height. We are permitted to go as wide as the fenders, but for version 1, we decided to keep it simpler and follow the straightish lines of the rear trunk lid rather than trying to make a curved fit to the fenders. Height wise it is pretty close - at the most upright position, it is at 10" (max legal). At our expected middle position, it is closer to 9". The side plates are at the max 100sq inches.

We will be finishing the front splitter tonight. It won't quite look like the photo you posted lol.

Still to go before autocross on Saturday:
- finish front splitter
- put ride height and alignment back to "pre-inspection" points
- oil change

[Canadian818]

Great work! Can't wait to hear how testing goes. What speeds are you reaching in auto x? Very curious about your splitter, but rather than ask a bunch of questions I'll just wait patiently ��

[Tamra]

Front splitter is ready! This is definitely version 1, as we already have things we want to improve.




It has F-brackets on the back that slot over a bar running width wise at the back of the bumper, which is bolted on directly to the frame (no bumper attachment). The bar is bent so that it is flush at the bumper level, and also touching the frame, which is up another ~1" or so. Once slotted in, it cannot be pressed back any further. On the front, it is quick release and attached to a bracket Andrew welded together and we bolted on to the frame. In total, it takes about 15 seconds to install/remove.



We would like for it to be stronger feeling, especially on the sides. For autocross we should never see much over 80mph, so for now this one should work. Version 2 will be made of a different, stronger, material and possibly include more bracing.

[Hindsight]

Splitter looks like it will be very functional, and also provide some cone protection.

It looks like you managed to overcome the hood fit issue that everyone else has, where the front corner of the hood meets the bumper. On most it intersects at a different point on the right vs left side. How did you get it so even?