Numbers make my heads hurt, need a quick ballpark answer

[PhyrraM]

OK, after spending a few days researching TD05 turbos, bmy head is about to assplode and I don't feel any closer to an answer. So time to ask voices of experience.

My engine build is underway. My engine builder is asking me what my HP goal is. Without too many details, it's a forged 2.35 closed deck stroker, so the hardware is good to 450+ HP. But, he can set various clearances (piston, rings, bearings, etc) tailored to my specific output. The looser the more HP it will support, but tighter will make a longer lasting engine. The key is finding a balance.

Heads are either stock WRX EJ20G, or stock EJ20K.

Ulitimate power will be determined by the turbo, of course (as will usable redline). The turbo will be a 90 degree inlet TD05 of some kind. That will not change on this engine build. It will be a stock, Subaru early WRX turbo for now. It will *possibly* be upgraded later, but will always remain a 90 degree turbo. Now comes the confusing part. I've read that a stock Subaru TD05 will support anywhere from 280-350 HP. I've read that a ported/clipped/frankenstiened TD05 will support up to 400HP. Few people state weather they are talking crank, adjusted, wheel or SAE HP. Most don't even mention engine size (but I assume 2.0). I've looked at flow charts. I've even emailed Deadbolt (no response yet). I'm now tired and admittedly a bit confused.

What I need is for a few peeps that have been there to simply say "Tell the shop to build it for xxx crank/wheel horsepower." My gut tells me to build to 300 wheel HP/375 crank HP.

I'm also tending to believe that this will be a fairly low RPM motor. I'm guessing that any TD05 on a 2.35 liter motor is going to be out of steam before 6500 RPM, and I'm OK with that. It's a daily driver/rallycross machine.

[GodSquadMandrake]

You're not going to make more than 400 HP with a TD05H-20G, although they say it's good for 440. With the EvoIII 16g or Zilla 16G you won't make more than 350 although most people can hit 300. 350 would be pretty hard but to get but you can do it.

The HP number on the TD05H-20G comes from Blouch:
http://www.perrinperformance.com/produc ... category=5


There is big difference between 400 HP and 300 HP. To go from 300 HP to 400 you would need to spend three times as much money. You will be blowing trannies left and right, smoking clutches, destroying axles and rear ends. You'll need a better intercooler, it would be wise to get an EWG. It's just a lot man.

I just got the 16G and called it good. It's cheap and it's just a big hurdle to go any faster than that. So I just built my motor for 300 HP being realistic.

[PhyrraM]

You're not going to make more than 400 HP with a TD05H-20G, although they say it's good for 440. With the EvoIII 16g or Zilla 16G you won't make more than 350 although most people can hit 300. 350 would be pretty hard but to get but you can do it.

The HP number on the TD05H-20G comes from Blouch:
http://www.perrinperformance.com/produc ... category=5


There is big difference between 400 HP and 300 HP. To go from 300 HP to 400 you would need to spend three times as much money. You will be blowing trannies left and right, smoking clutches, destroying axles and rear ends. You'll need a better intercooler, it would be wise to get an EWG. It's just a lot man.

I just got the 16G and called it good. It's cheap and it's just a big hurdle to go any faster than that. So I just built my motor for 300 HP being realistic.

Wheel or crank? That's becoming one of my biggest pet peeves. (next to not stating LEgacy or WRX when talking about an EJ20G ) In a Subaru not stating which your talking about automatically gives us a 20% +/- range (drivetrain loss). That's on top of the 15% +/- range from dyno/altitude/weather differences.

I know there is a big step there (300-400). I also know I won't cross it. But I will optimize for a modded TD05, it only makes sense. I don't realistically expect to see 400HP, but that 300-350 range is really cloudy. I was hoping to narrow it down some, but it doesn't seem too likely.

Thanks!

[beatersubi]

That much difference isn't going to matter that much for rallycross, anyway.
Perhaps you should be the authority on the matter by putting it all together and posting dyno charts.

[PhyrraM]

.........Perhaps you should be the authority on the matter by putting it all together and posting dyno charts.

I don't know about being the authority, but it will go together and you can be sure I will post charts! My only worry is that the money runs out before I can get a proper dyno tune. I'm not nearly good enough yet to trust myself to approach it's limits. Luckily, when that time comes we have some of the best talent here is SoCal.

[GodSquadMandrake]

Those numbers are wheel horsepower. You can look up dyno charts on Nasioc just type in like '16g dyno'. Yeah you will get a wide variety of results but you have to know how to interpret the results. Just because someone gets 180 WHP on 11 pounds of boost and stock exhaust doesn't mean that's what you will get!

But yeah if you put a TD05H-16G on there 300 WHP is realistic if you have the right modifications. If you get the EvoIII 16G, or the zilla 350 WHP is attainable. But those turbos are twice as expensive as a regular 16G and the difference in CFM is small.

It's very expensive to get dyno tuning. I would suggest doing a road tune yourself with a wideband o2 sensor and get the AFR's down to what you want. Once you have the driveability and AFR's figured out you can start to play with timing. Retard the timing one degree at a time until you get detonation and then back it off a degree or two. Once you get on the dyno it will be pretty close and it won't take as long for them to dial it in perfect. With the rates those guys charge the wideband will pay for itself. That way you can always retune it if you make a change to your engine in the future.

[PhyrraM]

Those numbers are wheel horsepower. You can look up dyno charts on Nasioc just type in like '16g dyno'. Yeah you will get a wide variety of results but you have to know how to interpret the results. Just because someone gets 180 WHP on 11 pounds of boost and stock exhaust doesn't mean that's what you will get!

But yeah if you put a TD05H-16G on there 300 WHP is realistic if you have the right modifications. If you get the EvoIII 16G, or the zilla 350 WHP is attainable. But those turbos are twice as expensive as a regular 16G and the difference in CFM is small.

It's very expensive to get dyno tuning. I would suggest doing a road tune yourself with a wideband o2 sensor and get the AFR's down to what you want. Once you have the driveability and AFR's figured out you can start to play with timing. Retard the timing one degree at a time until you get detonation and then back it off a degree or two. Once you get on the dyno it will be pretty close and it won't take as long for them to dial it in perfect. With the rates those guys charge the wideband will pay for itself. That way you can always retune it if you make a change to your engine in the future.

Thanks for defining WHP/CHP. It seems that all I've been doing is searching Suby sites for dyno charts. As far as interpreting them? I figured "check a few charts, looks at some flow maps, make a descion." Well, either I am over analyzing (engine builder seems to think I am) or I just can't comprehend until I go out and try it once for myself. Everything becomes clearer with experience, ya know?

I did notice that the "improvements" to the stock TD05 did seem to be rather small until you start swapping TD06 parts in. I'm going to see how it drives on a bone stock Subaru turbo and only then decide on any changes are to be made.

The car already has a wideband and an EJ20G Apexi Power FC w/datalogit. I have tuned the stock EJ22T myself with decent results. I haven't gotten any quotes to have it dyno tuned yet, but if it's really steep I will be doing exactly as you suggest.

Jamal, if your reading this how about getting a ballpark from HB Speed? I honestly don't know if we are talking $30 an hour or $300.

[Aerotech]

FWIW, I'm really enjoying my stock TD05-16G on the 2.5, it pulls hard right up to redline, running stock RS-RA ECU. No tune, just out-of-the-box components. I run out of 1st gear real quick.

[PhyrraM]

FWIW, I'm really enjoying my stock TD05-16G on the 2.5, it pulls hard right up to redline, running stock RS-RA ECU. No tune, just out-of-the-box components. I run out of 1st gear real quick.

Actually that helps alot. What is your Redline? 6500 on the tach? Or higher to suit the heads (on the orginal 2.0, I think they put it at 7000 for the RS/RA)? I'm assuming you've never been dynoed?

[beatersubi]

Retard the timing one degree at a time until you get detonation and then back it off a degree or two.

You mean advance?

[Aerotech]

Actually that helps alot. What is your Redline? 6500 on the tach? Or higher to suit the heads (on the orginal 2.0, I think they put it at 7000 for the RS/RA)? I'm assuming you've never been dynoed?

I believe the redline is 7K, but I've never hit the limiter yet, tho I have pulled it past 6500.
No dyno time. 440 grey-top injectors. I have a Haltech E-8 standing by, but not much time to play with it these days. I'm pretty happy with the car as it works now, it'll take a little while before I get bored with this level of power...