Going bigger??

[paul s]

I was thinking of upgrading my gt13 to a SBR bolt on gt35r(t04e 4inch shroud) but with only 2.0l worry about the spool up a little. Also I don't really want to go beyond the stock 7500rpm limit. Any suggestions are welcome . . I just don't think I can get much more out of that turbo. I'm running 27 psi on 98oct with almost no knock(.4-.7) and 15deg up top pushing 47lb/min(dsmlink) and 11.4afr.
thanks

 

[pneumo]

According to the info I have, the GT-13 is rated at about 60 lb/min, so you're not pushing the limits yet. Going from the GT-13 to a GT35R is not that big of a step.

 

[92awddsm]

As stated, you are nowhere near maxxing the gt13. You will max out your 750cc injectors long before you reach the limits of the turbo. At 47lbs/min, you are in the range of maxxing a 50 trim, not a gt13. I would invest in a smim, larger injectors, and possible slightly larger cams before upgrading turbos again. Just instlling a gt 35 isnt going to net much, if any more power or airflow. Evidently, you have either reched the limits of something else in your intake tract, exhaust system, or your tune is way off. Your profile is kind of hard to make out so I really dont know exactly what all you have done. And if you plan to stick to the 7500 rpm limit, you will just be going backwards if you move to a larger turbo. With what you have, I would step it up to 8k+ rpm to use the current turbo to its fullest. Anything larger is not going to be efficient at that low of rpm.

 

[paul s]

I have magnus intake and 272/272, going with larger cams will not let me pass e-test that is required here. The injectors are at 82% at 27psi 11.4afr. If the tune is off I have no idea where as I went over the car few times. boost leak test few times up to 30 psi. changed sensors, added extra ground. Decent timing with very little knock(less then 1)

 

[GstRacer]

what exhaust are you running?? Exhaust believe it or not but can kill the breathing of your motor

 

[CanadianTSi]

He's running a 3" Buschur exhaust.

I'm gonna say that Greddy FMIC is starting to become a restriction.

 

[donk]

Internal och external wg?

/A

 

[vintagemuscle]

I think that turbine housing is becoming a big restriction at this point. If you are going to go with a 35r i would highly suggest going with a t3 turbine housing.

 

[TSIMonsteR]

I disagree that the turbine housing is the restriction. and if anything, go with a t4 housing....

What is keeping you from running more boost? Have you thought about meth injection? Do you have a way to measure temps post intercooler?

 

[shleppy]

with a properly ported 1g head and quality sheetmetal intake manifold you'd pick up around 8lbs of airflow. Your amount of timing and knock are showing your intake charge temps are way to high even with 98 octane, showing the limits of your intercooler. Get a quality frontmount like the slowboy race and you'll be able to run more boost and timing without knock. Its all about the combination.

 

[Kevin Jewer]

15 degrees of timing is perfectly acceptable for lower octane fuel (98 is weaksauce IMO ) AFR is right where I would put it. Airflow is exactly what I would expect it to be for a 2 liter at 27 psi. Knock is normal.

The first thing I question is the reasoning behind not wanting to go over 7500 rpm? The stock DSM valvetrains take 8500 all day long, as do the motors. 8k rpm is usually enough to get the job done, I like to set the limiter to 8500 just so I don't hit it, in the EVO. With the 2g with a stroker and stock head I shifted around 82-8300. In fact if you really want to keep rpm down you might as well do a stroker and take advantage of the extra 15-20% airflow.

To answer the original question, as others have said, it will not be worth upgrading the turbo at this point. With a 2 liter it will take roughly 35 psi to max out the current one. In my personal experience, upgrading to another turbo while the current one is not maxed out will not increase airflow at the same boost level, unless there is an increase in the exhaust side flow. But this also bring more lag, and it's not always a good tradeoff (i.e. extra 400 rpm in boost threshold but only 1 lb/min increase, etc).

Your limitations are elsewhere. Octane is one. I run 117 at the track, which allows you to max out a turbo without getting knock, as long as AFR and timing remains appropriate of course. It would also let you run more timing and leaner AFR at your current level, but that won't be worth as much power as rasing the boost (airflow). Aside from that, you could work on things that will increase flow without raising boost, like increased displacement. You already have cams and SMIM, so there isn't a whole lot more you can do in this department.

 

[donk]

Also trading yoy sbr gt13 for a sbr gt whatever with the same housing seems kind of stupid if that is what limeting you, but i dont think the problem is in the housing either, the turbo shuld be good for more than 47 , or all the sale speak for this turbo is crap and i am toast wanting +400 whp on e85 (104 okt)

/A

 

[shleppy]

Um.. no smim, just extrude honed. He shouldn't need to run 35 psi to get decent airflow-maybe to max out that turbo. With well ported 1g heads, smaller cams and a smim I've gotten 54.5 lbs on a 53 lb turbo at 7400 and 28 psi with the air temp in the mid 70's. I've also got 50lbs at 24psi the same night. My friend dj got 578whp on a gt35r at 30psi with low timing, which is a similar sized turbo with ported 1g heads, smim and the same cams.

 

[Kevin Jewer]

I have magnus intake

Um.. Sometimes you have to read the posts I guess. Maybe I'm missing something?

54 lbs at 28 psi seems awefully high. I'm willing to bet this is on an uncalibrated MAFT.

 

[fourreGsixty3]

I would say follow what 95GSXracer said for upping your octane count go 110 atleast, this turbo can flow 60lbs/min, 47lbs isn't even scratching the surface. Also why do you want to stay at the 7500rpm limiter? This turbo is ment to go into higher rpm's, and like 95GSXracer said "The stock DSM valvetrains take 8500 all day long". With higher octane like c16, appropriate afr and timing to go with that higher octane, shifting at 8k-8300, and upping the boost to say 32psi, your times will be going down. Also look into meth injection, it ups the octane count of pump gas, so you can run higher boost levels, and it keeps the intake charge temps down, by the atomized meth/water mixture soaking up the heat, it also cleans up carbon deposits in your engine. the spool maybe a little slower but not by much...a couple hundred rpm or so. And to shleppy, he has a magnus SMIM.


Dustin

 

[CanadianTSi]

It would cost him a fortune to run 110 octane everyday, his 98 is a Mix of 94 and 110 to keep the cost down.

 

[shleppy]

Nope, calibrated maft. Switching back and forth between mas and maft both are dead even, although at the highest airflow there's probably some inaccuracy. Another clue that I've maxed out the turbo is that increasing boost isn't really increasing airflow anymore. Its typical to find around a 4lb increase from 1g heads, and again from switching to a smim at the same boost level. It's common for a ported 1g head, cams and smim combo to flow up to 44lbs at only 20 psi on a decent sized turbo, according to forced performance.

 

[hairybeanbag]

It would cost him a fortune to run 110 octane everyday, his 98 is a Mix of 94 and 110 to keep the cost down.

You have got to pay to play!

Time for a civic to drive to work. J/K

 

[fourreGsixty3]

It would cost him a fortune to run 110 octane everyday, his 98 is a Mix of 94 and 110 to keep the cost down.

I was refering to atleast 110 octane for track purposes. But running 94 octane with the 110 octane mix, and a 49/51 ratio of meth/water, would up his daily octane count near the constant 110 range, but he would just need a large resevior so he can DD with water/meth injection and that higher octane caoun that it provides.

Dustin

 

[paul s]

I have been running 98oct all summer and tuning for no knock, so with 98 oct and 25 psi I can tune for 0 knock full 4th gear pull and stock timing curve. At 27psi I get very little knock(.7-1deg). I guess I can experiment with running more boost and higher rpm to see what happens. The HKS springs shoud prevent valve float. I want to keep the car as daily driver. On the 18th we are going to a dyno to get some more numbers. thanks for all the ideas. Maybe its time to get a professional built head but its $$$$$$$, I was looking at Polk performance heads and 2000 is not cheap. I guess 120mph on a daily driver is not so bad..

 

[90blacktsiawd]

but he would just need a large resevior so he can DD with water/meth injection and that higher octane caoun that it provides.

Dustin

As long as he isn't putting it to the floor every time he gets behind the wheel even the base tank that comes with the kit can last a week or two at a shot. And having a 120mph DD certianly isn't anything to be ashamed of.

 

[shleppy]

I use my stock windshield wiperfluid reservoir and find that I only go through it around once a month. Water injection would really help out cooling down the intake charge and allow you to run more timing.