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At what RPM do you get full boost?

Posted: Thu Sep 11, 2008 7:32 pm
by Dr. Gonzo
I recently completed the TD04, 06TMIC, 45 degree intake, & 3" exhuast install and was very impressed with how quickly this thing spools up :D . In 5th gear I have full boost (11psi) by 2100-2200rpm :-D , this seems VERY good to me especially being at 5000ft ASL, but I have no frame of reference for this motor/turbo combo.
What are you guys seeing?
Stock dp, Stock turbo & intake? Stock turbo & DP? TD04 & DP? Ect..?

I ask because I put my boost guage in at the same time as everything else, so regretably I have no before data I *think* the 45 degree intake box helps a lot removing a few 90 degree bends, but who knows????

Posted: Thu Sep 11, 2008 9:31 pm
by 93forestpearl
4000 rpm :shock:

Posted: Thu Sep 11, 2008 9:50 pm
by impreza_GC8
My setup is too frankenstine to apply here but I have a question for the OP. Do you have any pics of your engine bay? I'd like to see the 45 degree intake setup and the way your TD04 sits in there. Thanks.

Posted: Thu Sep 11, 2008 9:51 pm
by RJ93SS
i am at about 3400 to 3600 and i hust put in my td04 and 06 ic...see mods below.

however, it fluctuates depending on vehicle spped beacuase on the highway i can hit it under 3000 in top gear (4eat)

Posted: Thu Sep 11, 2008 9:52 pm
by RJ93SS
impreza_GC8 wrote:My setup is too frankenstine to apply here but I have a question for the OP. Do you have any pics of your engine bay? I'd like to see the 45 degree intake setup and the way your TD04 sits in there. Thanks.

there is a write up on the 45 air, search it

Posted: Thu Sep 11, 2008 10:17 pm
by Dr. Gonzo
93forestpearl wrote:4000 rpm :shock:
Dang! Is that in 1st or 2nd gear or something?

I need to read the "how to post photos" faq then I can get some up, but I've seen some similar ones on here.

Looks like I'm spoolin' pretty quick, but again I was in 5th gear, which puts a good load on the turbo. Maybe this is in large part due to the 45 intake, haven't seen any other posts with this mod?

RJ93SS: what psi is your "full boost"?

Posted: Thu Sep 11, 2008 10:34 pm
by 93forestpearl
Dr. Gonzo wrote:
93forestpearl wrote:4000 rpm :shock:
Dang! Is that in 1st or 2nd gear or something?
GT2871R 56 trim @ 23psi ;-)

Posted: Fri Sep 12, 2008 5:19 am
by Dr. Gonzo
93forestpearl wrote:
Dr. Gonzo wrote:
93forestpearl wrote:4000 rpm :shock:
Dang! Is that in 1st or 2nd gear or something?
GT2871R 56 trim @ 23psi ;-)
"AHHHH, I see!" said the blind man :-D
What kind of numbers do you put down with that snail?

BTW-I miss living in the cities... near sea level and sooo close to brainerd. Now thats a road course!

Posted: Fri Sep 12, 2008 6:15 am
by 93forestpearl
You lived by Brainerd huh? I know a few people from there. I haven't been able to make it up to BIR yet, unfortunately. My car got T-boned a few weeks ago so now I'm looking for a clean shell.



Anyways, on the 22T longblock with some hot Delta cams and a Wiseco/Eagle bottom, I put down 293whp/322tq on a Dynojet. That was at about 20psi, down from the 23 psi I normally ran, which was also limited by my 650cc injectors. The night before I got T-boned I installed some 900's and was out tuning them when it happened.


When i do get a car back on the road with my nice drivetrain in it, it will have EJ25D heads on it running about 8.0:1 compression. I'm expecting around 350whp with them, since the EJ25D heads flow about 60cfm more than the 22T heads.

Posted: Fri Sep 12, 2008 5:14 pm
by Dr. Gonzo
Well, I was in Chaska, not that close to brainerd but a heck of alot closer than CO. I was able to hit 149mph on the front srtaight with my STi and you're putting down more hp than an STi...You'll for sure get the 'puckered' feeling :shock:

Wow, thats pretty good on the 22t heads!
Oh yeah, I remeber looking at the pics you posted of the T-bone, sucks.
Whats this 'nice drivetrain' going to consist of? What EM do you use? Oh and what RPM do you red line at? I suppose even 4K to 6.5K is a pretty decent power band, more than the 2K wide powerband on hondu V-tecs.

Posted: Fri Sep 12, 2008 5:26 pm
by RJ93SS
Dr. Gonzo wrote:
93forestpearl wrote:4000 rpm :shock:
Dang! Is that in 1st or 2nd gear or something?

I need to read the "how to post photos" faq then I can get some up, but I've seen some similar ones on here.

Looks like I'm spoolin' pretty quick, but again I was in 5th gear, which puts a good load on the turbo. Maybe this is in large part due to the 45 intake, haven't seen any other posts with this mod?

RJ93SS: what psi is your "full boost"?

stock td04 boost but with vacuum bypass sp i am at about 9ish

Posted: Fri Sep 12, 2008 8:11 pm
by 93forestpearl
Dr. Gonzo wrote:Well, I was in Chaska, not that close to brainerd but a heck of alot closer than CO. I was able to hit 149mph on the front srtaight with my STi and you're putting down more hp than an STi...You'll for sure get the 'puckered' feeling :shock:

Wow, thats pretty good on the 22t heads!
Oh yeah, I remeber looking at the pics you posted of the T-bone, sucks.
Whats this 'nice drivetrain' going to consist of? What EM do you use? Oh and what RPM do you red line at? I suppose even 4K to 6.5K is a pretty decent power band, more than the 2K wide powerband on hondu V-tecs.

Ha, I'm from Shakopee, lol.



Some of the stuff consists of an '05 6mt, Exedy Hyper Single, rear VLSD, H&R coilovers, RacingBrake BBK, etc.

I'm using a Link Plus G2. I have the redline set at 6800, but the hydraulic lash adjusters make going above 6500 pretty worthless. The 22T heads restrict the flow up to the point where short shifting at 6k is the fastest. They do pack a wallop of torque in the 4000-4500 range though!

With the 25D heads, she should scream up top, and have a broader band to play with.

Posted: Fri Sep 12, 2008 8:24 pm
by dzx
3800 rpm

Posted: Sat Sep 13, 2008 1:48 pm
by BXSS
On a EJ20G (2.0l) 4eat SS just stepping on the gas on idle 14-15psi on the JDM 90* inlet TD04 was @ about 2800-3000 rpms - I have not been on this turbo for a while now so the #'s are starting to get fuzzy.
Basically you could count to one & get the "t" sound out for two when full boost would kick in on this setup.
I did also track the car with this turbo & got the slow time on my sig....

Same motor, car, & tranny with a TD05-16G & EL header combo = 17-18psi @ about 37-3800RPMs actually kinda laggy but top end boost does not fall off past 15psi like it would on the TD04.
I'd say 10-11psi on the TD05 feels like 14ish psi on a TDO4.

I thought something was wrong with the slow spool but a few GC/GD Impreza guys told me they get full boost @ about 4k with a 16G/stock manifold on a 2.0 engine....

Posted: Sat Sep 13, 2008 5:50 pm
by Dr. Gonzo
Good data. Overall do you like the characteristics of teh EJ20G or the EJ22t better?

Posted: Sun Sep 14, 2008 11:07 am
by BXSS
Comparing the 2 motors in stock form + bolt-ons the TD04'd EJ20G @ just 10-12psi was WAY stronger than the ej22t @ similar boost levels.
The ej22t did have a little more torque below 2800-3000 rpm than the EJ20G, but once you hit that rpm # on the EJ20G it would just take off with MUCH better mid-high RPM power/torque

Car was equipped with the same

FMIC
Ported Airbox / K&N Filter / homemade MRT style resonator delete
3" TBE
Diamond coil pack
Walbro Fuel pump
Aeromotive FPR
Tranny Cooler
ECU/Sensors

on both motors (I have the EJ20G running off the ej22t ecu)

With the 16G on the 2.0 the mid to topend is improved even more & the pull is pretty strong.
I plan on tracking this car fairly regularly next season with a target time of 14.99 for bracket racing which should be easy to run with about 10psi on the TD05.

I also want to see what time it could post with a modified Torque converter & v-body + 18psi (which are my next mods for this car) - I'd estimate a very low 13.

I like the EJ20G sooo much that my plans for a dohc hybird ej22t are now scrapped & a V2 STi RA EJ20G (forged pistons + ported heads + better cams / valvetrain all stock) is in the garage waiting for installation in the SS when the GF8 EJ20G blows - the SS will stay 2.0 from now on!

Here are some comparison pics of the td04 vs the TDO5 & FMIC pics on the ej22t & EJ20G.
http://bbs.legacycentral.org/viewtopic.php?t=35542

http://bbs.legacycentral.org/viewtopic. ... c&start=25

Posted: Sun Sep 14, 2008 3:21 pm
by 93forestpearl
BXSS wrote:Comparing the 2 motors in stock form + bolt-ons the TD04'd EJ20G @ just 10-12psi was WAY stronger than the ej22t @ similar boost levels.
The ej22t did have a little more torque below 2800-3000 rpm than the EJ20G, but once you hit that rpm # on the EJ20G it would just take off with MUCH better mid-high RPM power/torque

I would hope so. Its hard to breath through a straw. It take s a lot of boost to get anything out of the EJ222T. My setup doesn't even really come to life until 15psi, and it only gets better from there.

I shouldn't have to run nearly as much boost when I get the 25D heads on.

Posted: Sun Sep 14, 2008 3:34 pm
by BXSS
Yeah I bet your car will be transformed with the new heads!!!!

Posted: Sun Sep 14, 2008 9:45 pm
by dzx
when I was running the 16G turbo it wasn't very laggy at all. It felt a lot like the stock turbo to me. The t3/t4 however feels very laggy.

Posted: Sun Sep 14, 2008 11:00 pm
by BXSS
Were you running it on a 2.2 or a 2.0?
From what I hear the ej22t gets max boost on a 16G @ about 33-3500rpms, while folks I know + folks on the RS club were getting full boost @ 4k on EJ20Gs & EJ205s.

The TD05 on my high compression 2.2l OBS-t feels like a VF11 in terms of response, but the SS's TD05 feels a little laggy in terms of spool on the low comp 2.0l...

My max boost RPM #'s are on a 2.0l 4eat car with idle (7-800rpm) launches - NO Brake torquing.
Launching a 5spd @ 4-5K or brake torquing a 4eat should give better spool #'s than what I get.

As far as the ej22t I'm sure you have to boost the hell of out of them with stock heads to make power as I got similarly slow acceleration #'s doubling boost levels - 0-60 times improved just .31 seconds @ 10psi vs. what they were @ 5psi with all of the mods listed above (5psi 0-60=7.79s, 10psi = 7.48s on the little tiny VF11(my 4eat was really slow with 9.70s 0-60s 100% stock no cels @ 8.7psi)).

Posted: Mon Sep 15, 2008 2:26 am
by dzx
Sounds like you might consider changing to a 4.44 gear ratio or a manual transmission if you find the time. I'm not too familiar with the tdo4 but if the turbo can hold boost you might look into camshafts for the engine.

Posted: Mon Sep 15, 2008 3:42 am
by scuzzy
1800rpm

does the stocker count? winds tight in an instant I swear.

Posted: Mon Sep 15, 2008 6:13 am
by wrxisthebest
hi, i own a 2003 wrx with a 2.0l, and i can get 17 psi with the td04 at 2500 rpm.. so 11 psi at 2100-2200 is about the same off the td04 on my car..

Posted: Mon Sep 15, 2008 1:21 pm
by BXSS
dzx wrote:Sounds like you might consider changing to a 4.44 gear ratio or a manual transmission if you find the time. I'm not too familiar with the tdo4 but if the turbo can hold boost you might look into camshafts for the engine.
The TD04 I have could not hold more than 15psi throughout the RPM range which is why I went to a TD05-16G (I run about 18psi on it).

I do not really care for Subaru 5spds so I plan on a high stall converter & v-body for the 4eat which should allow me to build boost on launch safely.
IPT says their modded t-converter should improve 1/4 mile times by about 1 second which is good enough for me!

Posted: Mon Sep 15, 2008 6:55 pm
by Dr. Gonzo
wrxisthebest wrote:hi, i own a 2003 wrx with a 2.0l, and i can get 17 psi with the td04 at 2500 rpm.. so 11 psi at 2100-2200 is about the same off the td04 on my car..
Interesting, is that on a manual tranny? I'm guessing you have at least the pre-turbo cat removed, how about post turbo cat(s)?