Mishimoto STI-08 Radiator install

Well I started installing the Mishimoto Radiator today. As it sits now it is ready to fill with coolant, but I just ran out of time so I will fill in final impressions tomorrow, but for now I will go through the install. For those wondering this is the Mishimoto model STI-08( it fits many Subaru models)

http://i1378.photobucket.com/albums/ah113/BBPeik/20160813_132232_zpslzk1ditd.jpg

 

Let me start by saying that this is a really tight fit. I had no room between the RX CP and the fan before and now a piece of paper won't fit in there.

 

The only reason that this radiator is not listed as fitting our cars is that on the top passenger side corner there is a threaded hole. It is for a coolant line that we do not have. This hole needs to be plugged. Fortunately it is just regular pipe thread and I actually had a plug that fit perfect in my extra parts drawer. If you do not have one they are real easy to find at a hardware store. Once that is in you are ready to go.

http://i1378.photobucket.com/albums/ah113/BBPeik/20160813_132221_zpsbyzjcybv.jpg

http://i1378.photobucket.com/albums/ah113/BBPeik/20160813_132247_zpsf7p4arat.jpg

 

So the rad drops in pretty as you please. No trouble there at all. The trouble is with the fan. There is no way to fit the fan and the CP in there, just not enough room. This radiator is about 5/8" thicker and all that extra moves towards the motor. So I put the fan in and then finagled the CP in there. Mind you it is even tight getting the fan in without the CP, so with it is impossible. I had to make a few mods to get things to fit.

1. There are three studs on the back of the fan. Cut those off.

2. The top passenger corner of the fan needs to be sanded down so that the hose clamp for the CP junction can fit. Just don't take too much or it will weaken the fan.

3. This is the tricky part. I used a dead blow hammer so as not to do too much damage. You need to make the CP coming up from the turbo oval instead of round. Basically making it skinnier. As I said be careful and work slow and things will be OK. You also need to bend the same piece of the CP to make it more close to the motor. This took me a lot of careful effort and you will have to figure it out for yourself. The end result is a CP that is 1/2" more close to the engine.

http://i1378.photobucket.com/albums/ah113/BBPeik/20160813_133234_zpsupjuua0c.jpg

http://i1378.photobucket.com/albums/ah113/BBPeik/20160813_191024_zpsg6qgjj1x.jpg

http://i1378.photobucket.com/albums/ah113/BBPeik/20160813_195612_zpssllhxeey.jpg

Once you have these mods done it will all go together. It is super tight, but it does fit. I will finish the install up in the morning and post my impressions along with my impressions over the next few days of driving.

Now someone needs to try a koyorad [emoji13]

OP:

 

How do you think the oem CP would fit? (or would it?)

 

Do you think that the AVO silicon CP would fit well since it's semi-flexible?

 

Are our radiator hoses the same too?

The OEM would not fit either. I tried to fit it, but it was still too big and at the wrong angle(insert inappropriate joke here). The AVO might work because it is flexible, but correct me if I am wrong, but I think it is even larger than the RX. That would make it real tough.

What about going to slimmer aftermarket fans?

 

Sent from my SAMSUNG-SGH-I337 using Tapatalk

That would work, but be far more effort I am sure.

 

SO I finished up the install today. Car took about an additional 1/2 gallon of coolant, so that will help I am sure. I noticed right off that the car was taking way longer to heat up than usual. Mind you I was in my garage with no fans on and it was 103 in the shade. The car finally reached 200 then just stayed there for a long time. I tried revving it up and all that did was cool things down to 190. SO obviously it was working. Finally though it reached the fan turn on temp of 208 and the car cooled right back down. I took it on a quick spin and it ran nice and cool the whole time. I can't wait until I get it on a good grade later in the week to see how the temps are there. Overall, I am extremely happy. Very good upgrade and a cool engine is a happy engine and a happy engine is a happy Brendan. That about sums it up.

 

http://i1378.photobucket.com/albums/ah113/BBPeik/20160814_193621_zpsdjd92xt9.jpg

Please put a link to this thread in the Performance Mods sticky. Nice work Brendan!

The OEM would not fit either. I tried to fit it, but it was still too big and at the wrong angle(insert inappropriate joke here). The AVO might work because it is flexible, but correct me if I am wrong, but I think it is even larger than the RX. That would make it real tough.

 

My AVO charge pipe snugly abuts, or contacts, against the OEM radiator fan cage. EDIT: Trimming the studs as mentioned by the OP and shown in the pictures is an absolute must.

Edited August 15, 2016 by mcg_

Quick update. The pipe plug that I used to plug that one fitting hole on the radiator was leaking a bit. It is a normal pipe thread, but I think it was not quite deep enough to seal properly. I did some digging and found an old temp sender that was the same thread. It was much longer so I was able to thread it in all the way. I used some thread sealant on it as well. Seems to be holding fine now. I will check again tomorrow to see if it is leaking but at this point it seems good. Just a heads up for anyone trying to do this. Use a thread plug that is deeper to ensure it seals.

I wonder how this would work in terms of gaining some of the space back? Would it be direct plug and play with our connectors?

 

http://www.rallitek.com/radiator-fans/7170-mishimoto-plug-and-play-aluminum-fan-shroud-kit-wrx-sti-2008-2014.html

It says it's plug and play with the connectors. Every Subaru I have ever worked on has had the same connectors for the fans.

It would work great. I thought about buying it, but it is pricey. I also was not sure how the coolant overflow would work. I am assuming ours is different than a wrx one.

Quick update. Today was the first day it was really hot since the install. It was about 98 on my drive home. Going up the same grade before in those temps my engine temp would climb to the high teens and occasionally even to the 220 mark. Today the highest my temp got was 210. The temp even dropped a bit as I sped up going up the grade. As they say the proof is in the pudding. 10 degrees cooler works for me.

BBPeik, these are the dimensions I am looking for on the stock radiator. Thanks Bud!!! The goal is to have a piece of plexiglass or ABS cut that fits nicely between the core end tanks and can be press fit into place (or taped/clamped if need be) to protect the fins of the radiator while the fans are removed and work is being done in the vicinity of the charge pipe, BPV, front motor mount, EBCS, etc. I had seen something similar in one of BigBopper's photos he took while doing some work on something in the engine bay and the fans were removed.

 

BBPeik, these are the dimensions I am looking for on the stock radiator. Thanks Bud!!! The goal is to have a piece of plexiglass or ABS cut that fits nicely between the core end tanks and can be press fit into place (or taped/clamped if need be) to protect the fins of the radiator while the fans are removed and work is being done in the vicinity of the charge pipe, BPV, front motor mount, EBCS, etc. I had seen something similar in one of BigBopper's photos he took while doing some work on something in the engine bay and the fans were removed.

 

[ATTACH]236866[/ATTACH]

 

Thin piece of plywood or paneling would do it, and cheap too!

 

It only takes about ten minutes to remove the fans and reservoir...

13 3/8" x 27 3/4"

Posting this here too in case someone is researching later and could use any of the info.

 

Changed the oil and installed the Mishimoto radiator and OEM STI lower temp thermostat today.

Part #s:

MMRAD-STI-08

21200AA072

 

Install of the rad was a bit of a pain. As a BBPeik mentioned when he wrote up his experience, I ended up grinding down a significant amount of the plastic fan support on the passengers side and one of the fan bolts. As it sits now everything clears but only just. I used a brass threaded cap from the hardware store to plug the extra hole that our cars do not use.

 

Results:

The car used to sit at 210-215 F in traffic, hanging out at ~200 in cruise, and occasionally getting down to ~190 if I coasted down an offramp.

Now it hangs out at 185-190 in traffic, got up to 192 after a third and fourth gear pull, and stabilized at 188.4 even when I coasted down the offramp.

I'm happy, hopefully this will help the ECU to be willing to keep the AC on next time its 127 out and I'm driving up that super long uphill section of the I-10 out by Coachella. (Last time I was seeing coolant temps up to 237 and the ECU turned off the AC at 222, not fun in the summer driving in to the setting sun...)

Im glad someone else was able to put this mod to good use. In the desert driving you are doing it will be a great improvement.

Looks like I will be doing this while the motor is pulled. Planning to use the mishimoto 3 row rad and their slim fan and shroud kit.

I've been super happy with it. No heat issues at all after install.

I am looking to pull the trigger on this, but will this work with the stock plastic charge pipe? Say it goes in, I am concerned massaging it to fit might split the plastic or rubbing against the shroud may wear a hole through it?

 

Also, checking out other aluminum rads, the Koyo looks to be about 1/4" thinner. Will this make a difference?

I'm not sure at all that the stock charge pipe would fit. Even with the Koyo I'm not sure, but I think you'd have decent odds. Your concern about rubbing makes sense to me.

Could you get a custom charge pipe made?

^yes, I can get a custom charge pipe made. I was already planning for one as part of my stage 2 because a few guys here have allegedly burst or blown out their plastic stockers at higher boost. I havent seen much worry about it here but figure better safe than sorry!

 

I was hoping to get the rad on before all the mods though to get a baseline on things. I am logging temps stock and I am not satisfied with the way the the cooling system pulls down temps at constant heavy throttle. Temps still in safe ranges (190-200 city, 200-210 spirited highway driving, maxed out at 230 at 137mph on a closed course), but it doesnt reign them in as well as in other performance cars I have observed. I'd really like more of a buffer before putting in the power mods.

 

How are your temps at now Sarang? Since the oil change, no more issues?

BBPeik, these are the dimensions I am looking for on the stock radiator. Thanks Bud!!! The goal is to have a piece of plexiglass or ABS cut that fits nicely between the core end tanks and can be press fit into place (or taped/clamped if need be) to protect the fins of the radiator while the fans are removed and work is being done in the vicinity of the charge pipe, BPV, front motor mount, EBCS, etc. I had seen something similar in one of BigBopper's photos he took while doing some work on something in the engine bay and the fans were removed.

 

[ATTACH]236866[/ATTACH]

 

GTEASER, is the radiator in the picture from a 5th gen GT?

 

I am talking to a local aluminum rad supplier and he is requesting a pic. He may have one without the turbo line outlet that needs to be plugged.

 

He wanted a pic of just the top tank but this whole rad shot would be better!

GTEASER, is the radiator in the picture from a 5th gen GT?

 

I am talking to a local aluminum rad supplier and he is requesting a pic. He may have one without the turbo line outlet that needs to be plugged.

 

He wanted a pic of just the top tank but this whole rad shot would be better!

I would assume that the picture is a 5th Gen radiator but I can't confirm or remember where I grabbed it from.