V6 vs. Flat 4 Boxer

[ichitaka05]

Originally Posted by SUB-FT86

I'm a V6 lover but a this car is better design for a Flat 4. But a bigger Flat 4(2.5L) would be the perfect medium between a 2.0L 4 and a 3.0L 6 cylinder engine. I love the Goldilocks engine choice between these two.

2.5L Boxer engine is nice... but are you forgetting something? Redline...

IDK why, but they can't keep the RPM high on 2.5 boxer engine.
Example:
EJ20G or EJ207 rev over 8k
vs
EJ22G rev lil over 7k
vs
EJ25D~7 revs only up til lil over 6k

If we put new modded FB/FA25 engine in FR-S, prob will be lucky if we can get 6,500rpm redline

Originally Posted by fatoni

how much lower is the cog of the frs motor compared to some of the v6 motors out there? how much heavier do you think a v6 is compared to the frs motor?

Most of V6 motors out there will have a higher COG than FA20.
How much heavier is V6 vs FA20? It's all depends on which one you're talking bout. VQ35~38, maybe 35~65lbs. Others like LLT, prob 70~100lbs or maybe more? IDK

[Splat]

pretty simple, the boxer achieves that lower center of gravity.

[SUB-FT86]

Originally Posted by ichitaka05

2.5L Boxer engine is nice... but are you forgetting something? Redline...

IDK why, but they can't keep the RPM high on 2.5 boxer engine.
Example:
EJ20G or EJ207 rev over 8k
vs
EJ22G rev lil over 7k
vs
EJ25D~7 revs only up til lil over 6k

If we put new modded FB/FA25 engine in FR-S, prob will be lucky if we can get 6,500rpm redline



Most of V6 motors out there will have a higher COG than FA20.
How much heavier is V6 vs FA20? It's all depends on which one you're talking bout. VQ35~38, maybe 35~65lbs. Others like LLT, prob 70~100lbs or maybe more? IDK

I still don't understand why a 2.5L engine can't rev that high yet you have a Porsche flat 6 with a 3.4L/3.8L and redline is around 7500-8000 rpms. Could it be that the Flat 6 engine balance is great compared to the 4 being average?

[ichitaka05]

Originally Posted by SUB-FT86

I still don't understand why a 2.5L engine can't rev that high yet you have a Porsche flat 6 with a 3.4L/3.8L and redline is around 7500-8000 rpms. Could it be that the Flat 6 engine balance is great compared to the 4 being average?

Boxer engine is same concept w Rotary engine. You can stack em up to what & how many you want. H8, H10, H12... it'll work... just not lighweight... also you're comparing H6 vs H4... that's a totally different story.

Some shop has put EG33 (H6) engine into Impreza (GM/GC) and was revving north of 8k. Just 4 cylinders got a limit w tq/hp most ppl request from the engine.

If they made new EZ30R (H6) w Toyota/Yamaha technology, prob they can push that engine 300hp/265tq w 9k rpm... but it's all guestimating

edit: & moving this to Engine section

[dori.]

Originally Posted by ichitaka05

2.5L Boxer engine is nice... but are you forgetting something? Redline...

IDK why, but they can't keep the RPM high on 2.5 boxer engine.
Example:
EJ20G or EJ207 rev over 8k
vs
EJ22G rev lil over 7k
vs
EJ25D~7 revs only up til lil over 6k

If we put new modded FB/FA25 engine in FR-S, prob will be lucky if we can get 6,500rpm redline

my understanding as to why the new FB can't rev high is because of the stroke being larger than the bore, unlike the EJ series

[ichitaka05]

Originally Posted by dori.

my understanding as to why the new FB can't rev high is because of the stroke being larger than the bore, unlike the EJ series

Larger? It's 86 bore x 86 stroke, my friend. Not larger nor smaller. It's a perfect IMO

[fatoni]

Originally Posted by ichitaka05

2.5L Boxer engine is nice... but are you forgetting something? Redline...

IDK why, but they can't keep the RPM high on 2.5 boxer engine.
Example:
EJ20G or EJ207 rev over 8k
vs
EJ22G rev lil over 7k
vs
EJ25D~7 revs only up til lil over 6k

If we put new modded FB/FA25 engine in FR-S, prob will be lucky if we can get 6,500rpm redline



Most of V6 motors out there will have a higher COG than FA20.
How much heavier is V6 vs FA20? It's all depends on which one you're talking bout. VQ35~38, maybe 35~65lbs. Others like LLT, prob 70~100lbs or maybe more? IDK

but how much higher? i doubt its significant. im pretty sure the bulk of the weight of a motor comes from the crank. also it is probably worth noting that you can put a v6 lower in the car due to its compactness. we shouldnt care about the center of gravity of a motor when it has no direct relation to the center of gravity of the car in general.

im not saying that i would like a v6 in this car. it was designed for a flat 4 (and seemingly designed well) so i like it that way. it just seems that people are equating a boxer motor to low cog which may or may not be true.

[ichitaka05]

Originally Posted by fatoni

but how much higher? i doubt its significant. im pretty sure the bulk of the weight of a motor comes from the crank. also it is probably worth noting that you can put a v6 lower in the car due to its compactness. we shouldnt care about the center of gravity of a motor when it has no direct relation to the center of gravity of the car in general.

im not saying that i would like a v6 in this car. it was designed for a flat 4 (and seemingly designed well) so i like it that way. it just seems that people are equating a boxer motor to low cog which may or may not be true.

Chill my friend. You asked, so I just replied. lol

Yes, some V engine can put it A LOT lower than FA20... but as of stock set up & price tag comparison, there's some difference between V6 & FA20. Also "significant" could mean different to everyone. 2mm might be BIG difference to some... Some may think differ.

As for COG been true or false on this car, we don't know. BUT til proven wrong, can't deny that statement

[Kamus]

I don't think a V6 would fit this car that well. But maybe a small flat 6 would do very nice (i think i remember an interview of Keiichi Tsuchiya where he wished the car had a flat 6)

Here's my problem with the flat four:
The car should feel peppy at sea level. But what about people like me that live at high altitude?
I live at 4,636 ft above sea level, and this affects N/A performance in a very significant way. at this altitude the HP loss in N/A cars is i think more than 10%.

I think a turbo would help out a great deal in this car, since weight wouldn't go up much compared to putting 6 Cyl. in there and it would also help low end torque tremendously.
And the big benefit for people like me, is that turbos don't lose nearly as much power at high altitude as N/A cars do.

So, even if it was a very small turbo i'd be more than satisfied. Since i'm more concerned with getting low end torque than peak power. And I wouldn't be surprised if a turbo version of this car, even with a smaller engine would keep up with more powerful N/A cars at high altitude.

[BlueLeader]

i had a 1995 maxima with just about the same amount of hp. the fr-s and maxima are different beasts. i wonder this myself as i am waiting to get my fr-s. but i've accepted that this car isn't about power, it's about agility. coming from a turbocharged car myself, i'll miss the haul but man the handling on the car is amazing.

[Captain Insano]

Originally Posted by carbonBLUE

What about a flat 6?

Exactly. Why isn't that on the list of options to vote for???




I would take them in this order...

• flat6
• flat4
• V6

OP, do you know how unique the boxer engine is? Only Porsche and Subaru make them anymore. I love flat engines for alot of reasons. I would LOVE if Subaru put a high revving flat6 in the BRZ. That would be totally badazz.

[Thunderchicken]

Originally Posted by ichitaka05

2.5L Boxer engine is nice... but are you forgetting something? Redline...

IDK why, but they can't keep the RPM high on 2.5 boxer engine.
Example:
EJ20G or EJ207 rev over 8k
vs
EJ22G rev lil over 7k
vs
EJ25D~7 revs only up til lil over 6k

If we put new modded FB/FA25 engine in FR-S, prob will be lucky if we can get 6,500rpm redline



Most of V6 motors out there will have a higher COG than FA20.
How much heavier is V6 vs FA20? It's all depends on which one you're talking bout. VQ35~38, maybe 35~65lbs. Others like LLT, prob 70~100lbs or maybe more? IDK

The reason why the 2.5 can't be rev'd very high is because of piston speeds and not allowing the motor to breath enough so you have to lower the rpm rev's. The best motor size for a 4 cylinder is 1.6-2.0 it allows for enough revving, throttle response, and plenty of hp/tq that is use able on the street.

[Laika]

Originally Posted by SUB-FT86

I'm a V6 lover .

With all due respect, may I ask why? I never got the point of a V6 for anything but economy ($$...fwd..etc). A straight 6 would appear to be a much better design in almost every regard. I always thought V6's were just the cheap boring way to make a 6 cylinder engine. I was disappointed about the GTR being a V6 and the G35/37 + 370Z could have been a lot sportier with an I6.

Not trollin, really curious, for all I know I was brought up viewing this incorrectly...

[dori.]

Originally Posted by ichitaka05

Larger? It's 86 bore x 86 stroke, my friend. Not larger nor smaller. It's a perfect IMO

no, the FB20 is 84 bore x 90 stroke