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Turbo Upgrade...please help

41K views 84 replies 8 participants last post by  turmic 
#1 ·
I have an 06' wrx with supporting mods: cobb stage 2 and spt intake. I'm in the process of upgrading my turbo and after extensive research this is what I have so far and need some experienced help...Just would like to get the most out of my setup.

I'm looking to get around 325-350 whp if possible?

Future Mod List:
-Forced Performance 68HTA turbo
-Forced Performance AVCS oil supply line
-TurboXS TMIC
-Grimmspeed 3-port EBCS
-Walbro 255 lph
-Grimmspeed 38mm ewg up pipe kit
-DW 750cc injectors
-E85 Tune

Questions:
1. Do i go with the 7 or 8cm turbine housing and do I stick with the stock (8psi) actuator or upgrade to the high pressure (14psi) actuator?

2. Should I get the turbo ported? What is the benefit?

3. Is it worth converting to an EWG with this turbo setup?

4. Will this setup destroy my stock tranny?

5. How does this setup look...anything I'm missing or should add?

Comments will be greatly appreciated and thank you to everyone in advance for your input!!
 
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#2 ·
1. I would do 8cm on the 2.5L. I would get the upgraded actuator, but you don't need it if you're getting EWG, in that case go for the 1bar spring on the EWG. You'll need to block off the IWG by welding or getting a bracket from GrimmSpeed to hold it shut.
2. Not worth it.
3. EWG is always fun and offers the best boost control when combined with the 3-port. It's optional at this point.
4. Yes, no, maybe. Bet on it though.
5. Looks pretty solid. I would throw a new turbo inlet in there while you have it all torn apart. I would also not do E85 if you only want 325-350. You'll be high 300's if you go with E85 and that's blowing up stock engine and transmission territory. Those 750's won't be big enough for E85 either. If you do insist on E85 get some 1000cc Injector Dynamics and you'll be all set. You can still sell your stock injectors to Deatschwerks for a couple hundred bucks back.
 
#3 ·
Thanks for the advice! Greatly appreciate it!

In terms of the tranny (not very knowledgeable in that topic yet) what would be your suggestion on upgrades or should I just go with a more conservative tune? At what HP does the stock tranny start to go to hell?

Thanks again!
 
#5 ·
Stock engine is usually ok at or under 350 whp/tq. Transmission is really hit and miss. Some guys run them with a lot of tq, some guys break them with 300tq. Only thing you can really do is keep a stock clutch in there to act as a sort of fuse to keep the transmission safe. Other than that you need to build the transmission with some aftermarket gears or do a full STI 6-speed swap.
 
#6 ·
the tranny can blow 2 ways. 1. under power like a 3rd gear pull or 2. shifting hard and the sudden power breaks teeth on a gear just like the first way or syncos or something else breaks from the sudden power. a weak clutch is only going to help the second way. the only thing to help the first way is not have the power there to being with. from what ive read 3rd gear breaks most. it could be from a power shift or it just cant take the pressure like a above 350wtq and the teeth snap off. drive it nice and keep it low and you should be fine.
 
#7 ·
When you say "a weak clutch is only going to help the second way." Do you mean in terms of a safety measure or "help" in terms of increasing the likelihood of my transmission breaking?

I'm typically pretty easy on my car but have the occascioly "get on it mentality" as we all do. I just don't want to do these upgrades and then blow my tranny from having fun here and there.

In that being said would it be worth the investment to get a "PPG 1st to 4th Straight Cut Synchro Gearset?" Or investing in an STI transmission? Or like you said "drive nice" and not worry about tranny upgrades?

Thanks for the input!!
 
#10 ·
Only difference in your car and Chris's car is that he has LGT style gears. The 02-07wrxs have the gears that can and will break with "get on it" driving with just 300whp/tq range. It may last you a while with reasonable driving. But, even NewToTheGame replaced his gears with his last deployment and was glad he did when he saw his old 07 gears come out. I wish he'd get back on here, but he told me everything on my cell.

Btw, Josh runs 326 whp/319 tq and that was enough to start beating up his gears. A 325whp goal will be possible with pump gas on the turbo you are looking at but, a 350whp goal will need more mods or E85 tune to get over 350whp.
 
#12 ·
Thanks for the info. I think I'll probably go for a good conservative tune for the time being until i can afford a tranny upgrade and just take it easy.

What is your opinion on the GS 38mm ewg vs 44mm? Also is it worth it to upgrade to the Tial wastegate for an additional $260 on the 38mm and an additional $360 on the 44mm :eek:
 
#14 ·
Ok this is going to be some technical turbo talk, but stick with me here....

IMHO the FP 68HTA is not a good match for a 2.5L. The 68HTA is a 16G with a big billet turbine wheel crammed into it with an undersized TD05 housing. This really chockes it on the 2.5L and it is kind of like the cheaper TD05 housing 18Gs that SBR produces, which just don't produce as much power as an 18G in a TD06 housing (i.e. the Blouch 18G).

Many people will point you to numbers and dyno charts of the FP 68HTA vs. the 18G, but that does not tell the whole story. Noteable tuners on NASIOC have all said the same thing....Off boost response, area under the curve (useable power), and driveabilty are all better with an TD05H-18G 8cm (TD06 Housing). My local tuner has tuned quite a few 2.5L WRXs/STis with the FP 68HTA and Blouch TD05H-18g 8cm. He says numbers are always very close, but everytime he goes for a test drive the Blouch 18G just feels better on the street.

Also, by the time you pay to swap out the 7cm housing which the FP 68HTA comes with to an 8cm you might as well have gotten a Blouch TD05H-18G (which uses the true TD06 housing) or Blouch 18G-XT. Last, FP has stopped producing the 68HTA and they are no longer available for sale new.

Do your homework, search some threads on NASIOC the info is all there. Just make sure to get an 8cm exhaust side as that is a MUST for a 2.5L and really lets it breath.

Edit:

EWG while good is unnessary for a DDer. 8cm and a good tune and you will not have any issues with creep. IMHO EWGs are loud and obnoxious (yes I know t is only when you get on it), but our cars are loud enough as it is. Also, I have been running a Blouch TD05H-18G 8cm since '08 on my 5-speed (EJ257 Hybrid swap). My frist tune at 16PSI (had for about 2 years) made 320whp/288wtrq and my current tune at 19PSI (last 6-7 months or so) makes 332whp/338wtrq. Both tunes are for 93 octane.

Finally, 750cc injectors are not going to be enough for E85. You will need at least 850ccs if not 1000s. I would definitely discuss this with your tuner and do what he recommends.
 
#17 ·
So I've searched NASIOC quite some time and have read many threads over the last few days and am about threaded out lol. Definitely am on the verge of information overload !Laugh!

Anyways did some more research on NASIOC and saw how people did say the FP 68HTA is a bit small for the 2.5L...thank you for bringing that to my attention!

So to be more clear on what I'm looking for:
-Fast spool...around 3-3.5K
-330whp/340wtq (basically what you're running right now) + room for growth (e.g. 400whp)
-Definitely bigger injectors...what is your guy's opinion on DW 1000cc vs ID 1000cc injectors?

My car is a daily driver and I love to drive in the canyons. I don't autoX or track my car.

I'll be using 91 octane as I don't believe many places here in CO have 93 octane. I also plan on getting an E85 tune as well.

I just want an awesome turbo setup with room for growth...I plan on this being my only turbo swap for this car as I'm already at 65K.

Therefore would the Blouch 20G-XT be a suitable turbo? Does it have the true TD06 housing?
 
#16 ·
Like Kirt said. 38 or 44 mm is just the diameter of the wastegate valve. You still need to get the Tial gate or it'll just be an open pipe to the engine bay and that is quite counterproductive.

You can see how it all goes together on mine.



Gate sizing is also not what you think it would be. Bigger turbo can get by with a smaller gate, a smaller turbo usually needs a bigger gate. The reason for that is the bigger turbo needs more exhaust gas to drive it, so it needs to divert less gas around it. It's the opposite for the smaller turbo, it doesn't need as much gas to turn so it diverts more around it.

That's also not to say the car will run like crap if you have too big of a wastegate, it's definitely better to have a bigger gate than too small of a gate because then even if it's completely open you can still overboost.

That said, I run the 38mm on my VF52 and boost control is spot on. When I go to the Dom 3.0 XT-R I'm still keeping the 38mm because I'll need to divert even less exhaust gas than I do now.
 
#20 · (Edited)
Sadly the fastest spooling turbo that will make 330whp/340tq that could be pushed to 400whp with E85. Would either by my turbo the Dom 2.5XT-R rated at 490 crank or the Blouch 20G-XT rated at 470 crank. The difference being the Dom 2.5XT-R is ball bearing and that helps spool up over thrust bearing turbos. Btw, you will need a butt load of money to get what your aiming for too. If you do a engine build, just get head and cam work done. I'm regretting it now and now I'm contemplating going backwards and doing headwork. Which will require the engine to be pulled again.

Btw, that's basically max crank hp figures that blouch came up with. Idk if they have a engine dyno or not. I tried to take a tour of the shop and was blindly shut down at the front desk by one of the blouch boys. They fear that shop secrets will get released with public traffic, photos being released, and insurance reasons that they don't want public by standers to get hurt. :(

All that I know is that Mike Blouch runs a Dom 3.0 on his car. My tuner has worked on his car and I didn't pry further to see if it was the upgraded Dom 3.0 or not.
 
#22 ·
Sadly the fastest spooling turbo that will make 330whp/340tq that could be pushed to 400whp with E85. Would either by my turbo the Dom 2.5XT-R rated at 490 crank or the Blouch 20G-XT rated at 470 crank. The difference being the Dom 2.5XT-R is ball bearing and that helps spool up over thrust bearing turbos. Btw, you will need a junk of money to get what your aiming for too. If you do a engine build, just get head and cam work done. I'm regretting it now and now I'm contemplating going backwards and doing headwork. Which will require the engine to be pulled again.

Btw, that's basically max crank hp figures that blouch came up with. Idk if they have a engine dyno or not. I tried to take a tour of the shop and was blindly shut down at the front desk by one of the blouch boys. They fear that shop secrets will get released with public traffic, photos being released, and insurance reasons that they don't want public by standers to get hurt. :(

All that I know is that Mike Blouch runs a Dom 3.0 on his car. My tuner has worked on his car and I didn't pry further to see if it was the upgraded Dom 3.0 or not.
Kirt--- I need to do my research on engine rebuilds as I honestly don't know very much. Therefore what are your recommendations for the type of work (specifics) that I would need to have done and what are some ballpark price ranges for that work?

How do you like the Dom 2.5XT-R? Are you happy with your setup?
 
#33 ·
8cm vs 10cm is the size of the exhaust housing. The smaller it is the quicker the turbo spools but the less top end it will have. Personally I would get the 10cm on the bb 20g on a 2.5L engine. Also, the 3" inles will allow the turbo to breathe a bit easier (think of drinking from a coffee stir vs mcdonalds straw). The 3" inles means you need to buy an aftermarket inlet and may need to delete the tgvs to get room for the larger inlet.
 
#34 ·
The sizing of your pistons and rings would be stock unless you get your short block bored. Its more of a question of what brand and the right forged metal then what size. There is some research needed and what prices that you want to spend. I can look it all up again. Chris is using a brand that I can't remember off the top of my head. I use CPs. Just don't get Mahles unless you don't want them to last for long on high horsepower.

E85 unregulation means that everytime you fill up with it. That the mix and exact octane could be different everytime. You'd have to basically make a tune for the lowest end mix to make sure its safe for every fill up. Which is kind of hard to do unless your tuner has a lot of experience with E85. The common flexfuel car has a OBD system that can change fueling based on the exact mix in the car at the time. Our car doesn't have that capability and it might be a real PITA to get it right for a while. OS, might let you tweak it with each fill up. You can test it with the test kit. But, if this is sounding like a PITA already. Then this is why some people don't run it.

I'll answer a couple things. Yes, the BB means it spools quicker and it could possibly be more efficent. Ask a tuner on his opinion on that. The 3' inlet means you have more air to play with. But, just like the 8 vs 10 arguement. The bigger exhaust housing and inlet can kill some spool up. It will get you gains in the high end though. Its a battle of what is more important to you. The coating could get you some advantages of keeping the under hood heat off the front of the intake side of the turbo pre intercooler. But, the exhaust side is still connected to the intake side of the turbo and the biggest source of heat is going to bleed through the ass end to the front side anyways. You can't stop that from happening. So, it might help some and be a bit of a bling mod at this point. Again do you think its necessary? There is a ton of research and questions in your head that you have to decide on which way do you want to go with your own car. Good luck man.
 
#35 ·
I would higly recommend forged pistons. I have coated CPs (custom spec; my tuner refuses to tell me the specs b/c he has them "special cut for him") and they are almost silent. Also, since the block is going to be pulled anyway some cams, valve springs, and retainers would do you wonders (i.e. Kelford 264/264s) and really allow you to hold power up top. The Kelford 264s really prevent that after 6000RPM drop off in WHP, while still keeping your lowend.

The risks of E85 were addressed by turnimic.

As for 3" vs 2.4" inlet and 8cm vs. 10cm....I think the inlet size depends on whether you want to do TGV deletes or not to go with the 3". As for the 8cm vs. 10cm, I don't think the 10cm hurts much at all. EVOs come with a 10cm 16G stock. I know it is something you are going to debate for awhile (I know I would), but in reality either will be good. Just consider the tradeoff a little more spool vs. a little more top end.

Just do it right the first time, as spending a bit more money now will save you money in the long run.
 
#36 ·
That's the truth, I wish I would've did head work. Now, I'm contemplating pulling the engine again just to do it. Basically a waste of more time and money. It should've been done the first time. But, it would allow my car to breath better from the better cams, springs, and heads. Which is what would allow me to squeeze all the numbers out of my engine that I could.
 
#37 ·
Many people used to say cams would do nothing until you went 400whp+ and a bigger turbo, like a 30R or 35R. Now people are realizing a mild grind on the cams and ones with a lot of lift (basically the Kelford 264s) really makes a difference w/a 18G or 20G.

I almost did not get the Cams. But, my tuner (Gregg of MGM) started showing me dyno graphs of 18Gs and 20Gs on stock heads and the fall off and conviced me. After my dyno he overlayed a similar build to mine, but w/o the cams and my power was almost exactly the same. However, at about 5800-6000RPM the other car fell off badly and mine never had much of a fall off. Even after 7000RPM I am really only loosing like 20whp until my 7500 redline.
 
#38 ·
I don't know why they'd think that. Cams are extremely helpful on N/A cars. So, why would it be any different for Forced Induction? They control how much air and fuel get into the cylinder. Which makes them extremely important. Granted, there is a lot of other things that you can do for more power. But, they shouldn't be ignored.
 
#39 ·
1. First and foremost I want to thank you guys for all the wonderful help/advice on everything and being so quick to respond to my questions....greatly appreciate it!!

Also, thank you for the great info on how to approach upgrading my block!

2. Need your advice once again. After doing some research, I'm really worried about blowing my transmission as I don't know the state of which its already in and thereby adding these power mods, is it going to put the icing on the cake (i.e. good by tranny)? I have $5500 cash to spend at my pleasure on mods but now am wondering where I should spend it?

If i put that money into upgrading my transmission (e.g. PPG gearset, STI swap) the time that I would have enough money to put into a turbo setup, i would probably be better off buying a new car due to mileage.

Is there anything I can do that isn't extremely expensive to further extend the life of my stock transmission other than driving like an *** hole, obviously?

Also, would it be worth the money to pull my transmission to see the current state of my gears and then go from there?

This just really ******* sucks as I've wanted to do a turbo upgrade for quite some time and now finally have the money saved up.

3. IYHO what would you do if you were me?
 
#44 ·
10 cm if you want the most out of the turbo. You better be able to afford a transmission in 6 months if you baby it. Even a 3rd gear pull will put a lot of stress on the stock gears. Just definatly don't clutch dump it or shift it harder than it needs to be. That got a member by for about 6 or so months on our forums on his 07 wrx. But, he had to lower the boost before he left for deployment; because his stock clutch was slipping. His trans got upgraded to PPGs by the time he got back. He saw his gears when he picked up his car and was kind of glad they got switched out. I believe 3rd was seeing some stress and his clutch was definatly slipping before he took it in. Now, he enjoys the car a lot more. ;) He is just rediculousy busy since he got back from deployment or he could chime in with his 2 cents. He also upgraded his clutch and flywheel with the new gears.
 
#45 ·
Update

Kirt,

Taked with Mike at Blouch and he told me to get the Dom 2.5 XTR. Here's what I have so far:

Parts On Hand:
-Deatschwerks 300lph fuel pump
-Injector Dynamics 1000cc
-STI splitter and bellows
-Grimmspeed EBCS 3-port-

Parts on Order:
-Blouch Dom 2.5 XTR 8cm housing
-TurboXS TMIC

My tuner said at our altitude of 5000ft that with the 10cm housing I wouldn't have spool until 48-55k and with the 8cm housing I would have spool around 33-35k.

So if I baby the hell out of my new set-up do you think I could get more than ~6 months? I hope to god so lol or I'm going to be riding my bicycle for quite some time !Laugh!

The parts will be installed next Wednesday and the protune on Thursday.

I'll keep you guys updated and will post my dyno once I have it

Can't wait!
 
#47 ·
Kirt,

Talked with Mike at Blouch and he told me to get the Dom 2.5 XTR. Here's what I have so far:

Parts On Hand:
-Deatschwerks 300lph fuel pump
-Injector Dynamics 1000cc
-STI splitter and bellows
-Grimmspeed EBCS 3-port-

Parts on Order:
-Blouch Dom 2.5 XTR 8cm housing
-TurboXS TMIC

My tuner said at our altitude of 5000ft that with the 10cm housing I wouldn't have spool until 48-55k and with the 8cm housing I would have spool around 33-35k.

So if I baby the hell out of my new set-up do you think I could get more than ~6 months? I hope to god so lol or I'm going to be riding my bicycle for quite some time !Laugh!

The parts will be installed next Wednesday and the protune on Thursday.

I'll keep you guys updated and will post my dyno once I have it

Can't wait!
I'd agree with c2bcoolwrx. Its not necessary, but it does happen. The stock inlet sucks and does tear.

Yeah, I don't know. I know Josh did some pulls on his car after getting it rolling in 2nd and/or 3rd. So, that is what helped destroy his clutch and sped up his need to switch to a lower boost protune map. To stop destroying his clutch and I'm sure it helped stress his gears doing those pulls. So, its going to take a lot of restrain from wanting to feel the power to keep the trans safe. I don't know about you, but I can't hold off from wanting to put my foot in it when I get a chance. [I drive my work van on the days that I work now and my STI on my days off.] So, of course my restrain is poor on back roads that are flat and empty. That's only thing that I can say. Your mileage may vary (YMMV) of course. Its one reason why I traded up, but I'm sure a lot of WRX owners get satisfaction to make the WRX stronger and quicker with the trans upgrades and power adders.

Josh's profile for those of you that don't know who I am talking about: NewToTheGame
 
#54 ·
I was initially going to buy a BPT turbo inlet but Mike at Blouch told me that the Dom 2.5 XTR comes with both an inlet and outlet and therefore didn't need to buy one? Is this something Blouch hasn't always included with their turbos in the past?


Another thing to think about is your oil pickup tube. Stock pickups have been failing and causing oil starvation. Getting a KillerB Oil Pickup is a good idea.

Oil Pickup Story - Subaru Oil Pickup Failure

I know I keep adding things on to your list...but, better safe than sorry.
How often does this occur? Obviously I would much rather be safe than sorry but at the same time that's another $250.

Thank you for making me aware of that though!
 
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