Compression ratio 12.5:1. Bye-bye Super charger & Turbo build?

[Syldrin]

that cat is the size of a 28R

[JDLM]

Hate the STS idea already

[Syldrin]

i've always thought the STS is a bad idea due to the exposure to the elements. i think we all know the possible dangers that could cause.

[WingsofWar]

Apologies accepted, thanks Driftster for the response and explanation of your thoughts. I agree with you, there are going to be some challenges in locating a turbo. And the challenge is gives even more pressure to OEM because it must be reliable too. And thermal efficiency has plagued performance boxer engines for a long time (ej turbos specifically). Stupid uppipes, and locating a turbo so close to intercoolers. Stupid heat soak. Intake manifolds getting retardly hot. Thanks for bringing up remote turbos too, iv only heard bad things about those systems. So thats out the window.

So a Turbo BRZ, possible and likely?....yes. Easy with its current configuration?...no

[Snaps]

Originally Posted by Driftster

And that STILL doesnt account for possible LOWER clearance issues of the sub frame etc..which if were the case the turbo would then have to be moved upwards aswell as foreward..

which would put the turbocharger nearly in front of the engine (fighting for space with the radiator fans) Which wouldn't be very safe for 1, it wouldn't be very efficient for 2 due to the lengthening of the exhausts..

What's so wrong with this, but mounting the turbo a little higher - as you've said? (Apart from the longer headers lessening response)

Also, why do you say it wouldn't be very "safe"? Safe as in a crash? Safe as in melting the accessory belts, etc.? Or safe in some other way?

Safe as in a crash - don't know how you would have come up with that one, so it's unlikely that would cause problems any more than any other car.
Safe as in melting accessory belts - I'm sure it wouldn't be hard to make a heat shield to protect these. Also, once again, I've seen quite a few people mounting turbo's in V8's (one example I can think of is a Supra with 2UZ/Twin Turbo) with no apparent problems with melting belts or any other components.
"Safe" in some other way - please explain?

Agreed on the wouldn't be as efficient, but you're not adding too much header pipe, much less so than a remote mount turbo. I see no reason it wouldn't be doable, especially for the amazing minds at Toyota and Subaru.

[coyote]

Not only will it be doable, it will be relatively easy.

[tranzformer]

Originally Posted by coyote

Not only will it be doable, it will be relatively easy.

Depends on how you define easy and how much moving around of parts you are willing to do.

[WingsofWar]

Originally Posted by Driftster

the company that decided a 12.5:1 compression direct injection 200HP box 4 was the best platform to sell to a crowd of people and marketing it as a car designed with "tuners and racers" in mind?

If we talk about subaru N/A tuners....this is the perfect setup. N/A flat-4 tuners have been striving for more compression. Less heat, better MPG, better overall better performance without going forced induction.

EJ20 and EJ25 N/A guys know what im talking about.

[WingsofWar]

Originally Posted by Driftster

That i'm all for....the potential for N/a growth..

but at the expense of everyone else?

That's pretty lame imho..

Of ALL the companies that should be able to make a happy medium engine capable of either/or you'd think Toyota and subaru could muster it.

at the expense of everyone else? hmm interesting im trying to understand what you mean. I really see where Toyota and Subaru are heading with the philosophy in this car. I mean if we are thinking of building a car specifically for the general population of tuners..this car would be completely different...and probably not even use a boxer engine.

They really disliked the idea of turbos, and AWD, and all sorts of gadgets that could make power. They wanted to throw away the common sense items of a modern sports car and really go back to basics.

Seeing it this way for the demographics of tuners..they threw away ALL modern tuners away..and wanted to flip the idea of sports car on its head.

N/A tuning sounds to be the intent and focus for the best experience philosophically. AE86 did fall into this category.

[Snaps]

Originally Posted by Driftster

Why this isn't a logical solution for this car is that it's nose has been reduced in size substantially in comparison to every other car on the subaru lot..Which is why the engine bay "seems more cramped" and this car has the minimum front overhang possible.

While you're correct in saying the front has been squashed, you haven't seemed to have taken into account that the engine has been pushed backward a VERY large amount, because it lacks the need to have Subaru's AWD system where the engine is mounted in front of the axle.

I think this is where extra (enough) room would come in to mount a turbo.

Let's reduce this clearance all together, and THEN ontop of that clearance reduction...extend the turbocharger out a few inches and then up and tell me you don't run into anything...

Assuming this car uses electric fans, you've already saved a bit of room with fan/radiator clearance. Also, so far we haven't seen any really good pictures of how the radiator is mounted. We've seen good pictures of the top support bar that goes between the headlights, but we've seen nothing of the bottom support, and nothing of the angle of the radiator, which could easily leave more room at the bottom of the radiator than the top.

We now have the potential of Subaru/Toyota throwing a 20lb turbocharger at the nose of the car, 20-30lbs in charge pipe...and an intercooler ...All over the front wheels..

And now you see why they didn't make it in the first place. Turbo is not what this car is supposed to be! (This isn't aimed at you directly, just everyone on the "needs a turbo" side)

In the event of an accident you now have a prop blade spinning at 100,000 rpm atatched to a cast iron lump that is sitting at in excess of 300F which is now free floating in your engine bay..

There's reasons why companies who produce amazing turbocharged engines..Never have the turbocharge as openly exposed as is to be expected in this case..

So does this apply to the likes of the Mitsubsihi Evo's, Dodge Stealth/Mitsubishi GTO's, Toyota Celica GT-4's (All-tracs in US) which have turbo's mounted up front stock?

We're talking melting accessory belts
melting plastic end caps on radiators
boiling off paint from metal it's riding up against..

Something as simple as a Turbo Beanie is used on Supra's and this fixes the melting paint problem above (turbo isn't mounted close to the radiator in a Supra). They're cool enough to touch even after a decent stint of boosting.

I'm sure Subie/Toyota would come up with something more elaborate than that, but it shows it's easily fixable.

Another option would be ceramic coating, which is also suppsoed to keep temps down, though I've never seen it myself.

Have you noticed the location of the turbocharges in relation to these belts in these builds?

Yes, and that's why almost none of them run heatsheilding around the turbo.

the company that decided a 12.5:1 compression direct injection 200HP box 4 was the best platform to sell to a crowd of people and marketing it as a car designed with "tuners and racers" in mind?

Technology has to advance at some point. Leave the direct injectors alone if you or your tuner doesn't know how to tune them?

[CyberFormula]

Originally Posted by WingsofWar

at the expense of everyone else? hmm interesting im trying to understand what you mean. I really see where Toyota and Subaru are heading with the philosophy in this car. I mean if we are thinking of building a car specifically for the general population of tuners..this car would be completely different...and probably not even use a boxer engine.

They really disliked the idea of turbos, and AWD, and all sorts of gadgets that could make power. They wanted to throw away the common sense items of a modern sports car and really go back to basics.

Seeing it this way for the demographics of tuners..they threw away ALL modern tuners away..and wanted to flip the idea of sports car on its head.

N/A tuning sounds to be the intent and focus for the best experience philosophically. AE86 did fall into this category.

Yes i agree. Its like how porn has alot of botox, and surgeries and make up done now. Also photo shops and video editing.
We should go back to the basics where its all natural baby:happy0180: and most people just can't stand it when its not artificial.

[Snaps]

Firstly, a few points needs to be made about the compression ratio of this engine.

You imply you wanted it to be for "everyone", so people could choose what they wanted to do with the engine. You come across as though you're making this argument in a way that implies EVERYONE wants to turbo this motor. That is doing the exact opposite you want of this car. Making this car able to be turbo'd easily would require lowering the compression ratio, doing this would then mean the people that want to keep the car NA are shafted. If you then still wanted a decent power level (200hp NA) at that lower compression, Toyota/Subaru would have had to put a lot more time/money into developing a high-power low-compression NA engine, raising the cost of the car itself which then takes away the market of the car.

Point 2 about DI - BECAUSE of the Direct injector cooling the cylinder + air/fuel mixture, you can have a higher CR without detonation. A good example of this is the IS-F, which I believe has a 13.5:1 static compression ratio? If 13.5:1 is the "limit" of an NA engine w/ DI before detonation, then this means this engine (4U-GSE/FA20) would be much more suited to a turbo than a port-injected engine running a 12.5:1 CR. It certainly isn't impossible to add a turbo at that compression ratio, it just means you can't run as much boost.

Finally - IF someone plans to change the rods, in most cases I have seen, they also change the pistons - meaning your points about the shape of the piston are likely next to moot.

With every new car that comes out there have been problems with modifications - In Lexus/Toyota's case, it's the ECU, with Nissan's GTR it was the gearbox and warranty. This car will be no different, and it will also be no different in the way tuners and modifiers come up with solutions to these problems. If the Direct Injection really does turn out to be a problem - block off the supply to the DI fuel rail... If the ECU doesn't cope with this well, replace it... If the piston causes problems when changing the rods, then swap the pistons out for flat ones, and swap the headgasket to lower the compression. I think you get my point. People will mod this car no matter what it takes, they wil continue to mod as they have done for a long, long time.

And if it's all too much of a headache for you to be on the cutting-edge of modding, then find a different car!

[blur]

So swap an Ej207. I dont see the problem here.

[arghx7]

Originally Posted by Driftster

- The drastically sky high compression atio of this car serves ONE purpose above all else in this application and it is not the production of power, it is the fuel economy.

The 12.5:1 compression ratio combined with precision atomization of the direct injection system is the very reason this car gets
27mpg city and 30+ highway.

Yeah, so what? Do you think people want to get raped at the pump? I'm sure you know Subaru and Toyota have to pay out the ass in taxes if they don't have good enough gas mileage.

ONTOP of that, lowering the compression ratio on this engine BEFORE giving it to the N/A tuners NOW gives the N/A tuner even MORE opportunity to produce power...

What's your point. Why would Subaru or Toyota engineers care about this? Because you read somewhere that they are trying to sell to tuners? You keep forgetting that aftermarket tuners are typically 10-15 years behind the OEM's. They barely understand what they are messing with and they have very poor equipment in comparison.

However neglecting the market as a whole is a terrible idea..Resulting in missed opportunities at massive capital gain.

I can tell you right now that there is much more monetary incentive for Subaru/Toyota to make the engine according to its current design than the way you and a (relatively speaking) small percentage of potential buyers might want.

The compression ratio isn't the ONLY deciding factor in boost naturally, but you're also treating the atomization the in cylinder injector brings on as a cure all for detonation, when in fact it's more of a band aid....It's more of a "persistent methanol" injection

Tell that to all the OEM's who are using the homogenous charge, high geometric compression ratio direct injected concept.

You are also failing to leave out that the entire geometry of the pistons in these high compression has been tailored to run in OEM configuration.....Meaning the dome shape of the piston (as posted prior) is now shaped to work primarily within the boundaries of the off the assembly line power plant..

Yup. That's how most modern direct injected engines work. The shape of the piston bowl is a big deal.

So now you've got a car designed to work at it's oem static compression ratio..
and throwing in a drastic dynamic compression change like forced induction..


Have a look around the industry buddy, and look at all the new cars which are being force fed like crazy in the aftermarket..you'll see they all share a
common bond..

They don't use direct injection..

Although their compression might be a little high (ex BMW s65) their R&D work is a based off of the same tuning methods that have been used for years and years and years and years on race engines with higher than 8.5:1 compressions

Hence my comment that the aftermarket is usually far behind the OEMs. I'm sure in the 80s nobody understood how to tune a 4A-GE when it came out.

Except if you understood how imperative the dish on that piston was to the effectiveness of the direct injection you'd understand how your attempt at "making my point about the shape of the piston next to moot" ......was moot...

The combination of the in cylinder atomization with the dish shape is what gives proper cylinder cooling and proper /more efficient burn..

without that Dish shape...all you're doing is spraying fuel onto a side of a cylinder bore..

The mixture formation in the combustion chamber varies under different conditions but you are correct. So changing out the fuel system will not be an option for a long time, and putting a turbo on it will be difficult. So go buy an older car and modify that.

Except when modding becomes a difficult task/chore and more of a hassle producing minimal gains for maximum work.....the modding/tuning of the car hits a crest/comes to a head...and from there very little development takes place, and the car spends the rest of it's years in niche groups and club meetings filed with people who love blowing their money on unsuccessful products

You are certainly right. Platforms can stagnate, and there is a good chance this will be one of them. You buy it for what it is, not for what you can turn it into.

If this car never comes with a factory turbo engine then don't expect the platform to go anywhere in terms of power. Buy it for what it is, not for what you can make it.