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turbo question


304border
01-18-2002, 11:42 AM
Which turbo is gain more power for my p11.??
could u guys tell me please ASAP

G-Forces
01-18-2002, 01:57 PM
A big one! ;)

2002G20Racer
01-18-2002, 05:38 PM
Bigger is better, as long as your engine can handle it...

Cue-Ball
01-18-2002, 06:06 PM
Bigger is not necessarily better. A larger turbo is harder to spool with a relatively small engine like the SR20. If you get a turbo that's too big, you won't be able to utilize it to it's fullest because you won't have enough air going through it. The T25/28 is what's used on the SR20DET because it can give decent power (up to ~250hp or so) and still spools quickly. If you want more power than that, you're going to have to do some research. I highly suggest you read the Turbo forum on http://www.sr20deforum.com/ . That should answer most of your basic questions and get you headed in the right direction.

b-b00gie
01-19-2002, 12:33 AM
Originally posted by Cue-Ball
Bigger is not necessarily better. A larger turbo is harder to spool

Yes a larger turbo takes longer to spool. You can ease this problem with a ball bearing center section and extrude honing. The question asked however was which turbo will get you the most power, and that was correctly answered with "the largest one you can fit".


Originally posted by Cue-Ball
I highly suggest you read the Turbo forum on http://www.sr20deforum.com/ . That should answer most of your basic questions and get you headed in the right direction.

I suggest you read the SE-R.net archives and look for stuff written by Rob Cadle and Mike Kojima.

However on the SR20DEforum I've found that half of the people posting info about turbos do not know JACK about what they are saying. There are some decent people who are knowledgable on there (Rob Cadle, Louis Anaya, Zak Nillson, Jay Hassinger are a few). For the most part the rest of them are a bunch of banana eaters....

MONKEYS!!! ...be careful ;)

nis.k.a.
01-19-2002, 03:27 AM
T88......hehehehehehehe

Cue-Ball
01-19-2002, 03:44 PM
Originally posted by b-b00gie


Yes a larger turbo takes longer to spool. You can ease this problem with a ball bearing center section and extrude honing. The question asked however was which turbo will get you the most power, and that was correctly answered with "the largest one you can fit". MONKEYS!!! ...be careful ;)

Again, bigger is NOT necessarily better.

While i totally agree that the T25/28 will not make the most power, not only does a larger turbo take longer to spool, but there are some turbos which are large enough that a 2.0L engine cannot use them to their fullest. Now, i don't claim to be a turbo expert, i only recently started studying turbo technology...hell, i don't even own a turbo car. But you cannot tell me that a T88 will make more power on a 2.0L car than a smaller turbo would. 2 liters is just not enough to spin a turbo that large to it's full potential.

I've read the stuff by Rob and Mike. Those guys definitely know a LOT more than i do about this stuff. But it doesn't take a genius to know that throwing on a big turbo will not necessarily make big power. Especially not without doing all the other mods required to get the most out of the engine.

So, i would say that bigger is better to a point. Once you get past a certain size you will need a bigger engine in order to make the turbo worthwhile. Would you agree with that b-b00gie?

b-b00gie
01-19-2002, 05:48 PM
I agree with what you are saying regarding turbo theory. But I still stand by my comment.

The question asked was: which turbo will get you more power, not which is best for our cars.


It is true that our motor would need tremendous work to get a T88 to its full potenential, but that is not to say that using it at half its potential wouldnt be good enough.

If you slapped a T88 on your car right now, yes the lag would be horrible, you would probably only start making boost at 5500 rpms or so. Thats not very much headroom to build boost; about 2000rpms before you hit redline. You will never see the big T88's potential (900hp???) but you may see 300+hp.

While this setup would really blow because you never start to make boost until you're high into the rpm range, and you will only see your top HP @ redline, you would still make more peak power compared to a more efficient T28.


The T28 would be a better fit because it starts making boost a lot sooner and you do not have to hit redline to see full boost. In general you would be using the turbo a lot more of the time. You would be making power much lower in your power band, while the huge T88 is puttering along to build boost. However, once the T88 makes boost, look out.


On a side note, Rob and Mike are very knowledgable. I've speaking with Mike privately for some time now. If it wasnt for his guidance I would have made a lot of mistakes due to recommendations of some of the SR20DEforum.com members, which is why I said to watch out...

P10DET
01-19-2002, 07:20 PM
Originally posted by b-b00gie


I suggest you read the SE-R.net archives and look for stuff written by Rob Cadle and Mike Kojima.

However on the SR20DEforum I've found that half of the people posting info about turbos do not know JACK about what they are saying. There are some decent people who are knowledgable on there (Rob Cadle, Louis Anaya, Zak Nillson, Jay Hassinger are a few). For the most part the rest of them are a bunch of banana eaters....

MONKEYS!!! ...be careful ;)

I couldn't agree more. There is a lot of misinformation on that forum. I could go on, but just be careful about the information you get there.

P10DET
01-19-2002, 07:26 PM
Originally posted by Cue-Ball
Again, bigger is NOT necessarily better.

True, but don't subscribe to the old-school horsepucky that a big turbo isn't good for a small engine and can't spool worth a crap - especially without a bb center.

Before Mike built Searl's car (now Ryan's), nobody believed that a T04E would work with an engine as small as the SR20. The big issue is proper sizing. I don't mean physical size, because that doesn't mean jack. You need to have maps and know what to do with them. Of course, getting a hold of maps is the hard part.

Hot ticket right now on the SR20 is a bb center GT3037.

JustinP10
01-19-2002, 07:54 PM
I know some of the people here in Az have been experimenting with turbos other than the t3 or t4 line of turbos more commonly used with some good results. I know of one application that isgoing to be used for track racing, so he wants something quite a bit different that some of the other people, that's why he went with something different. however, even with the more common drag racers, i know they've been going with different turbos and getting good results. But i do also know they did their homework! I wish i knew a 1/2 of what they know about turbos!

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