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Okay, I did some searching on this forum and I couldn't find it, so here we go. I've been looking at Vivid Racing and their turbo upgrades. The IHI VF23 turbo says it can put out about 180 Kw at the wheels. I did a conversion and that's ~241 hp at the wheels. Now, I had a discussion with my friend that has the turbocharged Si...it went something like this:

Him: Dude the new STi only puts out 210 hp at the wheels!
Me: Yeah that's good, what's your problem?
Him: Dude that's crap! I don't think it'd be worth it!
Me: WTF are you talking about? How can you say that?
Him: 'Cause my car puts out 240 at the wheels, so that's crap compared to my car!

Well okay so my friend is a little...obtuse...but that got me thinking. He's got (supposedly) 240 hp on 2 wheels, but can that really be compared to 240 hp on 4 wheels, or is it more like apples and oranges? I'm new to a lot of the performance-oriented stuff so can anyone please enlighten me on this?
 

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I don't think you can compare that. The WRX was dynoed at 160-170 HP to the wheels from certain car magazines. That's less HP than some modded Integras but the WRX is still faster. Think of the STI as getting 210 HP to each wheel or each set and the other car getting 240 HP to two wheels or one set :).
 

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I am dynoing at 251 at the wheels on my car at 15.5 PSI (with obvious many upgrades). Stock is around 180 which is about 20% power loss. My ITR put out around 163 whp stock which is 18% power loss. Stock the ITR runs high 14's. Stock the WRX runs mid 14's. That's about right. I think your friend has a point. The difference is not as much as you may think between a 2WD Honda and an AWD Subaru. That being said it is super easy to get over 275 whp on the Subaru (albeit NOT with the smallish VF23). It isn't as easy to get that out of a Honda and without a turbo almost impossible.
 

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From a roll that 240 fwhp will beat a 240 awhp? I notice that my car is terribly slow because I'm stock. I have terrible turbo lag, and I don't want to mod my car at the moment. Due to money and my dealership which isn't mod friendly.
 

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The difference is traction.

If a turbo/supercharged Si and WRX put down the same amount of peak hp TO THE CRANK, the WRX will have the upper hand. Traction becomes a problem on boosted Hondas. Not a problem with the WRX. The lower hp figures to the wheels is due to AWD. The power isn't lost, it's just sent to more places.

As God said, it's easier to get power out of the Subaru. Thus easier to get more out of the stock block.

I assume your friend is running the stock block since he's only putting down 240. Expect it to blow up far sooner than your WRX :rolleyes:

On the highway, I'd say boosted Honda's have it. They're geared good for pushing the top end.

Racing isn't always about power though :)
 

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I was talking to a Subaru tech at the dealer, and he stated that the hp distribution to the wheels is 60/40. 60% of the hp to the front wheels and 40% to the rear wheels. Is this statement true?
 

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Discussion Starter · #9 ·
Yes, it varies between auto and manual. According to Autoweek, the manual is a 50/50 and the auto is 60/40...but if I remember correctly, the 60 was in the rear rather than the front. I could be wrong though.
 

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I'd probably suggest Up-pipe & downpipe..... not really more torque so to speak, but it will definitely give your turbo room to breathe.... get that pre-turbo cat out...

Also, take out that silly silencer/resonator thing out of the wheel well, add an ITG panel filter... or K&N, stick a velocity stack between your stock air box and fender wall....

Just my $.02
 

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There's more power loss due to the drivetrain in AWD vehicles compared to 2WD. For 2WD vehicles, we estimate a 20% drivetrain loss. I have no idea the approximate percent for AWD.
 

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I think it was import tuner magazine this month who has a WRX in its power pages...

They got very good torque gains from a downpipe (unless I'm wrong -- recalling from memory here).

But they also had turned up the boost using an AVC-R.

What's drawing you away from an MBC?
 

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It all comes down to how long the track is. If you are street racing I would think AWD would be better because all you do is pull ahead and claim victory. In a 1/4 mile situation a 2wd with the same hp as the AWD is gunna catch up and beat you. Not only does the AWD have greater drivetrain loss, but there is also a weight disadvantage.
 

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tan said:
There's more power loss due to the drivetrain in AWD vehicles compared to 2WD. For 2WD vehicles, we estimate a 20% drivetrain loss. I have no idea the approximate percent for AWD.
On a dynojet I use 18% on hondas for my formulas. On the Dynapack AWD dyno I use 20%. On an AWD roller type dyno I'm sure the loss is greater but they are too difficult to tune on. Prefer Dynapack.
 
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