inline 4 vs flat 4

[HakosukaBunta]

Read it wrong. Delete Sorry

[Rival M]

Back on topic.

In '05 I test drove a few cars including an '04 WRX, an RSX Type-S, and a Cobalt SS/SC. I ended up buying the Chevy.

One of the things I didn't like about the WRX was the boxer engine's sound down low. It's nothing like other 4 cylinders. But I've been near a later Legacy that had the new 2.5L motor and it didn't sound anything like the WRX.

So do we think Toyota will tune the exhaust differently than the Subaru version?

[G4BROKE]

Back on topic.

In '05 I test drove a few cars including an '04 WRX, an RSX Type-S, and a Cobalt SS/SC. I ended up buying the Chevy.

One of the things I didn't like about the WRX was the boxer engine's sound down low. It's nothing like other 4 cylinders. But I've been near a later Legacy that had the new 2.5L motor and it didn't sound anything like the WRX.

So do we think Toyota will tune the exhaust differently than the Subaru version?

I believe that they (toyota) will use equal length headers.

[Cal]

If it becomes a problem we'll usually move it, but otherwise we are mainly here help those with questions, and stop spamming and bashing.

Wait you mean we are not here as supreme rulers of all things interwebz and banning people just cuz?

[ra23celica]

Open the pod bay doors Cal...

[modifiedMR]

the horizontally opposed flat 4 is superior to the inline flat 4, especially in rwd form.

why?
-lower center of gravity
-less inherent vibrations
-shorter allowing it to be mounted closer to firewall (for a rwd car)

in a sports car, making it handle is one of the most difficult things to accomplish. with this setup, it will be easier to make weight distribution better. one of the great things about the original AE86 was it's weight and weight distribution. this car has that, more power and potentially lower center of gravity!

IMO, if done right, this car can handle as good or BETTER than an s2000. it should have more tq, too. will it be faster? depends on weight, etc...

[drperry]

The only place the boxers seem to really fall behind is fuel economy... But the newest generation seems to be catching up!

[ej25ti]

The only place the boxers seem to really fall behind is fuel economy... But the newest generation seems to be catching up!

what are the new numbers for the FB?
im too lazy to look lol

[Ryephile]

The FB engine in the '11 Forester is rated at 21/27 mpg with both trannys. Lop off 600 pounds, significantly reduce drag with less frontal area and drag coefficient and I'd hope the FT-86 can get over 30 mpg highway.

[ryun84]

They gave the new mpg numbers for the 2012 base model Impreza. 36 mpg highway. I say that's improvement. People have been complaining about its design though.

[topcat]

what was the question again? I thought the OP was asking about the difference between inline and flat fours...

for what its worth, a flat four is strong, light, balanced and very low in profile, so helps with weight and positioning (low for CoG); an in line unit is not as strong, and in bigger capacities needs power sapping and heavy balancer shafts, but it is easier to mount transversely for FWD cars, and arguably, has better fuel consumption. But the flat four has more character, and is - for me - one of the particular reasons I'm interested in the car.

As for winter driving ^^^, the best thing is proper tyres and sufficient weight over the driving wheels for traction. Or a Subaru.

[Cal]

OP was comparing the driving experience between the two.

[modifiedMR]

saying it consumes more by comparing a fwd to an AWD subie isn't fair. put an awd flat engine against it and then your talking apples to apples.

crv - 21 city 27 highway = 23 combined
rav4 21 city 27 highway = 23 combined
matrix 21 city 28 highway = 24 combined
from a little searching
evo's and sti's are both seeing ~19-22 combined

the evo and sti's getting pretty much the same mileage with 2 different layouts shows that the flat vs inline doesn't really make much of a difference.

weight is a key factor. a 2400 lb car with a 2 liter non turbo engine might get ~30 combined mileage or more today, but a 3200 lb car with a 2 liter engine will get ~25. mind you, the examples are for none performance engines.

[ej25ti]

saying it consumes more by comparing a fwd to an AWD subie isn't fair. put an awd flat engine against it and then your talking apples to apples.

crv - 21 city 27 highway = 23 combined
rav4 21 city 27 highway = 23 combined
matrix 21 city 28 highway = 24 combined
from a little searching
evo's and sti's are both seeing ~19-22 combined

the evo and sti's getting pretty much the same mileage with 2 different layouts shows that the flat vs inline doesn't really make much of a difference.

weight is a key factor. a 2400 lb car with a 2 liter non turbo engine might get ~30 combined mileage or more today, but a 3200 lb car with a 2 liter engine will get ~25. mind you, the examples are for none performance engines.

idk, im definitely lucky if I get 18mpg in my STi!

[drperry]

idk, im definitely lucky if I get 18mpg in my STi!

Take your foot off the floor

[modifiedMR]

idk, im definitely lucky if I get 18mpg in my STi!

lol. i had read that some get that low. even a guy going from a gto complaining about getter worse mpg on the sti. lol. awd and boost can suck down gas! some people were saying that they got 26-27 average mpg, which i find hard to believe. 22 mpg sound about right. my mr2 gets that on premium, but it's running uber rich with how i have it right now. a pfc is sitting in my room. either going to be sold or installed. mr2 may go....

drperry has a point. might be a case of "lead foot."

[ej25ti]

i get on it at times, but overall i try to make my daily commute a lil more conservative
so im not sure

[Cal]

i try to make my daily commute a lil more conservative

You could always drive one of these.

Of course you would be required to turn over your balls first.

[ej25ti]

Of course you would be required to turn over your balls first.

and wear a bag over my head

[bersh]

i like smart cars... they are fun.. you can drive on sidewalks and nobody notices...

im gona try to find some pics from when we did that..


oh and anyone know if we r gona have to use premium in this thing? idk what ur supposed to us in the fb engine

[topcat]

I'll run the thing on 99+ octane Shell V Power - best for the engine, best for power.

[Cal]

99? Best we get is 93.

[modifiedMR]

99? Best we get is 93.

their rating system is different. 99 is something like 94 octane comparable in our standards.
it is always best to run whatever the car is tuned for. higher octane in a lower rated engine is not better at all. lower octane means that it is more volatile to ignite. using higher octane means that it's harder to ignite and allows a performance engine to run more compression, timing and/or boost before making the fuel ignite. running higher octane won't really help the engine, but typically won't hurt it. if a car is running wrong from wear (like alot of carbon build up), the compression will be higher and higher octane may keep the engine from exploding (from detonation). running lower octane in a higher rated engine means that the fuel could possibly ignite before the spark ignites it. this is called detonation. severe detonation makes engines go boom!!!

this is why race engines use higher octane fuels. it's harder to ignite, so they can add more pressure (a few ways to do this) to the combustion cycle in order to make a more potent explosion.

[MrVito]

OK, I'm know I'm coming into this convo a little late, but I noticed a few things, mostly that I'm not willing to go through and multi-quote, but bear with me please.

Ryephile mentioned the 11 legacy with both tranny's, I imagine you meant both differentials, when actually, there are three, front, rear, and center. Even an open differential is another point of drivetrain losses which equals less power delivered to the ground, and worse fuel economy, though phenomenal traction is the positive end result.

The weight and coefficient of drag will be significant factor in fuel economy, but both seem to be pointing in the right direction, particularly the 2800lb curb weight. As an example, one of my S14's weighed in at 2848lbs with me (183 at the time) and 3/4 tank of gas. This particular car was making 227rwhp on a dynojet in 92 degree ambient temperature and still managed to get 26mpg mostly city when I kept my foot out of it (S14 SR20DET, minor mods, 15 lbs, fmic, etc). Considering the PI/DI setup that yoda's will be running, and assuming the final drive will be something in the 4.08 ( if they use an R200 rear) to 4.11 ( if they use a subaru R180 POS rear), and proper gearing on the six speed, I fully expect this car in N/A form to easily break 30mpg highway.

I'm more interested in seeing if Toyota can hit the 200hp and 190+ lbft mark with the PI/DI setup, considering the FB20 is the 2011 Forrester is making 170hp @ 5800rpms and 174lbft tq @ 4100 rpms, I can only see them making this happen with a revised cam profile or increased compression, vs the Forrester 10.5:1. Though the AVCS on intake and exhaust, could mean a still more aggressive cam profile, though less than initially thought, combined with the elimination of the TGV's to possibly meet this number. It will be close without sacrificing MPG's and maintaining emissions requirements.

Now the port injection / direct injection combination is what has me excited. PI is a bit more precise than DI due to it being a longstanding well known technology, which I imagine will largely be used for idle/start up operation, with DI for moderate to high load applications. The exciting part is the potential hp from running a DI setup. The Soltice GXP/Sky Redline community hasn't seen an upper limit for either the HPFP ( high pressure fuel pump required for DI) nor the DI injectors themselves. Some of these cars are at/breaking the 700rwhp limit on stock fuel + meth injection. Though the factory C/R is a full 1.3 points lower than the N/A B20 at 9.2:1. Not to mention the square bore and stroke shared with the evo X/ genesis and SR20 engines (86mmx86mm).


So it looks like if I don't swap out the FB20 for an EJ, I'll be putting pennies away for rods, pistons, head gasket, ARP hardware, and a nice turbo setup on an N/A Scion model. Any way you look at it, this car is going to be a great handling one with the low and centered engine/trans combo + lsd, plus huge potential with direct injection. I can't wait!

[ForRealSomeday]

Tires, tires, tires...

Step one:
Purchase a set of Blizzaks and some rims from tire rack

Step two:
???

Step three:
Profit!

[modifiedMR]

Tires, tires, tires...

Step one:
Purchase a set of Blizzaks and some rims from tire rack

Step two:
???

Step three:
Profit!

wft? lol!

MRVito> when he ment tranny's, I think he meant the auto (CVT? in them) or the manuals and not the differentials. I do understand what you are getting at with the drivetrain losses (weight and transfer losses). I think you are right about the fb getting 200 hp, but I don't know if it will make the 190 tq you are aiming for. Usually pushing a NA motor means a drop in tq and raising topend power. It is more difficult to raise overall power, except if you are right about higher CR. I would imagine it will be a combination of higher CR, larger cams AND some intake/exhaust/intake manifold flow work to get it to 200 hp. I am hoping more like 210-220 hp and 180 tq. This car won't need too much tq to get it going. The s2000 only had 160 tq and it was somewhat fast. Add 20 tq and more lowend grunt from the boxer and it will be faster. That's why I'm hoping it will weigh 2700 lbs and have that power. Possibly push very low 14 second quarter mile passes.

[Cal]

wft? lol!

South park reference.

[ej25ti]

speaking of, i loved my blizzaks, jussayin

[modifiedMR]

South park reference.

no, I knew the south park knome reference, but where the hell did that come in? lol.

tires make a huge difference and I am wondering if I should purchase a set of crappy rims (have good 215F/255R tires on them) and keep my 2 piece forgies for the FRS?

[Cal]

I should purchase a set of crappy rims?

Take out all the other and re-read that. Then answer your question.