new to dsm turbos, few basic questions.

Hello everyone. I just installed a t25 turbo on my civic dx 1.5L
right now its just street tuned, (took out some timing addded some fuel)
anyway i'm liking the t25, it spools incredably fast! full spool is 2800-3000rpms but the power falls off very quickly at 5500. the dx model redlines at 6200 so im wishing i would have gone with a14b or small 16g.

So anyway i'm looking for some help, i dont have the money to build the motor, so basically my motor can only handle 220whp max. soo im wondering what would be the best turbo for 200-220whp and wich would be faster in the 1/4mile? a t25 w/14psi? or b14 w/12psi? or small 16g w/9-10psi(do you guys agree with that as far as being equivalent with one another?)

The only thing i really like about the t25 is right when you shift the turbo is still at full spool and it feels very torquey. but then top end sucks, i need something that will atleast make power to 6k and still gets full spool when i shift.
Im not very good at explaining things, so sorry if theres any confusion.

Also does anyone have a compressor map for these turbos? or atleast know the compressor flow for each one?? thats the question i really want to know, but cant find info know where.

Next thing i was wondering are the flanges the same size on all 3 turbos? same with the o2 housing? or am i gonna have to get a different exh. mani?
Ok thats all the questions i can think of right know. TIA!

p.s. where does the t28 fit in? isnt it bigger than a 14b but smaller than a small 16g?? and i just found this on ebay, seems to good(cheap) to be true. anyone know the compressor rate on this t28>
http://cgi.ebay.com/ebaymotors/TD04-H-Turbo-T25-T28-w-Internal-Gate-Greddy-Internals_W0QQitemZ8012761107QQcategoryZ33742QQrdZ 1QQcmdZViewItem

The t25 is good for airflow in the mid 20s lbs/min, 14 is 30 lbs/min, 16g is 38 to 42 lbs/min depending on the variant. If you aren't going any higher than 220 whp I would go with the 14b. It has been proven to run over 300 whp on DSMs. Spool up is just over 3000 rpm on a 2 liter.

It will bolt up to the Manifold and O2 housing just like the T25, but the mitsu turbos (14b/16g) have different oil feed and drain lines. The feed line will be a banjo fitting, and the drain line's bolt holes are a little closer together (you can modify your current drain line to ork I'm sure). The compressor discharge setup is totally different too, it's on the top. Depending on your piping setup a J-pipe might be all you need to adapt it. DSM vendors like www.slowboyracing.com sell them if you want to take a look.

I Don't care much for T28s, but thats just me. In your application they might be just fine. It will come in between a 14b and 16g, and will be a direct bolt on replacement in all aspects, so it may be a good choice for you.

Good luck :)

The only thing i really like about the t25 is right when you shift the turbo is still at full spool and it feels very torquey.

I wish it felt torquey on my Talon... Oh well, time for a bigger turbo. lol :evillol:

WOW THANKS! useally it takes a few posts for someone to answer the questions lol, ok i thought of a couple more questions, what is the WG spring rates on the 14b and small 16g? Also what should i expect to pay for these turbos? My friend is selling his small 16g for $150 is that a good deal?
How much boost is the 14b & small 16g good for? When do they stop making power rpm wise?

Well check the turbo for shaft play, if it has none than its a good deal. Usually buying used turbo's just means trouble unless its a good friend and not fuckin you over. By the way you get fast responce in here because its the mitsubishi forum not the honda :ylsuper: . So here is some numbers for you.

250-275 hp a 14b can push this out, at 275 its pretty much burnt out. (Mitsubishi turbo)400cfm
275-300 hp a small 16g will push this. (Mitsubishi turbo) 500cfm
second option, for 2g owners, but IMO a slightly worse option than a small 16g, is a Garrett big t-28 turbo. 500cfm
300-375 hp big 16g 550 cfm. Also, a EVO III 16g is slightly larger than the big 16g and can make up to 400 hp, 550cfm but has some modifications to it versus the b16g.
18g will do 400hp, more top end power less low end. 600cfm
20g will have slower spool but great top end power, and can do more than 400hp but does 400 nicely. 650cfm.
50 trim is too big for 400 hp IMO.

The 50 trim is only 2 lbs/min larger than the 20g, 50 vs 48. I couldn't even tell the difference. Also, I really hate CFM numbers for turbos, I much prefer mass flow ratings. Otherwise that looks decent :)

The 14b and 16g will have a spring pressure of 9-10 psi. The T25/28 should be closer to 7-8 psi.

today my friend sold me a vtec head, i will be putting it on in a few weeks. This head will move my redline to 7500k instead of 6k so now im thinking i might want to go with somethin with a little more top end like the small 16g rather than the 14b does anyone know what the 14b is good for rpm wise? also heres a weird question for you guys, lets say for example a small 16g@8psi makes the exact same power as a 14b@12psi.
Would one tend to be harder on the motor than the other? and wich would be faster for drag racing? (givin they both have same power?)

You're never going to find such a drastic difference in power vs boost pressure when both turbos are well within their efficiency ranges. An example I like to use is my TDO6H 20g at 25 psi, moved 47 lbs/min. Upgraded just the compressor wheel to a GT40 56 trim (GT35R, etc) which is MUCH larger and a more modern/efficient design, and airflow was still 47 lbs/min :) At 30 psi though the 20g would fall off while the 56 trim was just warming up. This is a good comparison since the 14b and 16g both use the same housings and turbine wheel. Actually the turbine housing is upgraded from a 6cm to a 7cm, which may help top end VE a little.

On a 2 liter motor with stock cams and intake manifold a 14b will hold ~22 psi to 7500. 16g will hold 25-26 psi. Increase VE with cams/intake manifold though and that number will drop. Decrease the displacement and the boost it will hold to 7500 rpm will go up. I would say either turbo will not drop off to redline in your case wit hthe boost you will end up running. ;) Which makes sense, since even the 14b can do 300 whp (~30 lbs/min) which is more than you said you plan to make.

god i wish i had kevin's intelligence.

I wouldn't wish that on anyone :icon16: A big part of it is really just 5+ years of playing around with these cars, and not being afraid to try things, which fortunately I have the means to do for the most part. It comes with time...