T25 from SR20 Newb Questions
 

I'll be purchasing a BEGI 1.6 T25 direct pulse manifold and had a couple questions before purchasing:

1) I read that a T25 will fall flat on it's face after 6k rpm. Is this true?

2) How much longer will a T3 take to spool vs a T25, RPMs-wise? I will be tracking this car and would prefer faster spool.

3) I have a HP goal of ~185 hp - 200 hp. Is the T25 the budget turbo of choice for this goal.

4) Does the OEM T25 from SR20s already come w/ a wastegate actuator?

5) Will the BEGI-S downpipe fit the SR20 T25 w/ out modification?

Thanks.

1. Not really. There's a definite torque drop-off with this turbo, but it's not horrible.
2. Depends on the size of each. Search for some various T25 and T3 setups and you'll get an idea.
3. T25 is perfect for your goals.
4. Some do, some don't. Depends on your specific turbo.
5. Yep. SR20 T25s are standard 5-bolt flange.

my t3 vs. samnavy's sr20 t25:

http://www.boostedmiata.com/dynos/scott_vs_sam.jpg


http://www.boostedmiata.com/lars_t25/larst25002.jpg


take my dyno with a grain of salt....i have a bit of work done to spool it that fast. :)

One thing you need to consider when dealing with the SR t25 is the AR size of the exhaust side. I believe mine is a .64, which causes a bit later of a spool compared to my old .48 ex side, but allows the power band to shift to mid-high rather then low-mid. The turbo will easily support your HP goals. You will most likely need to clock the turbo, and modify the OEM wastegate. Do a search and you will find info on this topic.

^ modify the wastegate to have the compressor outlet point down? Then yes. Otherwise you can work with it the way it is.

If you are going to be "tracking" this car, you need to define track a little better. Auto-x or a road course?

Depending on how small the T25 vs how large a T3? The difference could be anywhere from 200 to 2000 RPM depending on the turbos. In some cases it might not matter, in others the spool time in critical.

If you are going for auto-x the small T25's make the most sense. If you are running on Willow Springs on the big track (an exceptionally fast road course) you want a much larger more capable turbo.

As far as the budget turbo for 200 HP, it's the T3S60 or a chinese T25 variant. The real deal Garrett GT25 series turbos are not budget turbos.

Mark

PS - Your HP goals are pretty modest for a road course car and fine for an auto-x car.

Get a chinacharger T25 and let me know how it is!

Why dont you get a chinacharger t25 and let me know how it is?

find me one thats cheap and why not. T2 foot print


there's a few gt28s on ebay...

:rolleyes:

Go look on ebay. ;)

I did i didnt find any cheap enough.

Brain i did some research and the GT chinchargers are no good! I asked 350 people who had bought them, and not a single person that used it didn't have it fail.