FRS FA20 turbo vs FRS lsx/2jz

[OmarGC]

Originally Posted by Reaper

My requirements were be light. Rwd. A toyota. Everything else was up to me.

This was big for me as well... I initially hoped it was have a 3s or similar engine when it was in the early concept stages. It's the major reason why I'm swapping... Because out the box these aren't Toyotas. Design yes, but when it comes down to it they're not.

It was between 2jz, choice of toyota v8, and a LS3. Being a bit of a purist LS swap was thrown out rather quickly... Missing my jzx chassis history one morning I decided 2j would be my only option.

[Reaper]

That's why I have a lexus v8 powered corolla.

[w.k.s.]

Originally Posted by Reaper

My requirements were be light. Rwd. A toyota. Everything else was up to me.

But it's a subaru? Although I love almost every part that had a toyota hand in it.

[Reaper]

Toyota designed it. Subaru built it. Toyota gave them a rear end a transmission and an efi. Toyota actually built the prototype out of a hacked up legacy.

[ZDan]

Originally Posted by Poodles

Perfect example is 2JZ vs LSx. 7 mains vs 5

[Vracer111]

For a non-daily driver...LSx is the route I would want to go.

The main thing that irks me about my FRS is the Boxer motor... Subaru motors are very quirky and not even in the same league as Toyota motors.... have had experience with 2 other Subaru's (both EJ motors - 2.2 and 2.5, not my vehicles) and now this one, and yep it's Subaru 'quality' motor alright. My last time I will get a car with a Subaru motor in it... very looking forward to testing out the 'baby' FRS with a modified proven I4 Toyota motor which has been out for about a decade.

To me if you are going for 400+hp with FI on an FA20 , you might as well throw a grenade in the engine compartment and just get it over with... unless you are going to do it right and spend the $$$$$$ to do EVERYTHING REQUIRED to make it reliable enough (transmission cooling, shielding for the coil pack closest the exhaust to help extend the shortened life [only expecting 1 year of functioning is not acceptable], cooling system overhaul, getting the heat out of the sealed engine bay, oil cooling and baffling system, figure out the solution to the lowish oil pressure at high rpms.) And for that amount you might as well just go with a custom LSx build and keep it normally aspirated and much more reliable... see Vorshlag's ongoing Alpha project (this is a forum members car):

http://vorshlag.smugmug.com/Projects...8839&k=t45GCwQ

[Mikem53]

Your ignorance and toyota fanboy is showing..
Piston slap was an early LS1 issue on the C5 that was corrected with new rings. and it was just noise, not a reliablity issue..

Lol.. A straight 6 needs to have more mains.. The LSx actually have more support due to the shorter crank.. Nice try..

The fa20 does not have full variable valve timing.. There is no variable valve lift on this system.

The fa20 fuel system is a mixed bag of tech.. If you like cricket sounds and overly complex programming.. This system is for you..

The beauty of the LSx is that it makes lots of reliable power, in a compact proven lightweight package that is affordable! That's not the case with the toy straight 6

Originally Posted by Poodles

Keep in mind even LS motors have weaknesses (piston slap for starters). HP/liter isn't a definitive measure of "stress" on an engine either. Engine layout plays in a hell of a lot.


Perfect example is 2JZ vs LSx. 7 mains vs 5, piston oil squirters, inherently perfect balance, etc


Also, don't get me started on the full variable valve timing and dual injection system of the FA20 being lightyears ahead of most LS motors.


Still say if your goal is only 500HP, the LS is a waste of money (hell, Full Blown did over that on a stock FA20 and a build FA20 should take that all day)

[Sideways&Smiling]

Originally Posted by Reaper

Toyota designed it. Subaru built it. Toyota gave them a rear end a transmission and an efi. Toyota actually built the prototype out of a hacked up legacy.

Was it a Legacy? I thought it was an Impreza.

[Reaper]

Oops my bad.

[Sideways&Smiling]

Originally Posted by Reaper

Oops my bad.

Yeah, I think the whole idea for this car was inspired by the drift team Team Orange converting Imprezas to RWD for competition. That's honestly the beginnings of the FRS/BRZ/GT86, I think.

[Poodles]

Yes, 7, 2 bolt mains that hold more HP per cylinder than the LS1 can with 6 bolt mains...

Originally Posted by Mikem53

Your ignorance and toyota fanboy is showing..
Piston slap was an early LS1 issue on the C5 that was corrected with new rings. and it was just noise, not a reliablity issue..

It was also an issue on f-body cars, and no, it caused excessive oil consumption.

Originally Posted by Mikem53

Lol.. A straight 6 needs to have more mains.. The LSx actually have more support due to the shorter crank.. Nice try..

Again, you don't know what you're talking about. There is a support for each rod on both sides while there is support for each pair on a V8. If you want to talk about "needing," the LS motors need 6 bolts to hodl the mains in place while the 2J does just fine with 2.


Straight six is the strongest engine design, there's a reason any serious diesel motor uses that configuration.

Originally Posted by Mikem53

The fa20 does not have full variable valve timing.. There is no variable valve lift on this system.

Since when does LIFT = TIMING? Reading comprehension? It has full control of the timing of intake and exhaust while most LS motors have no control.

Originally Posted by Mikem53

The fa20 fuel system is a mixed bag of tech.. If you like cricket sounds and overly complex programming.. This system is for you..

Oh, you're really reaching if you have to bring the crickets into this

Originally Posted by Mikem53

The beauty of the LSx is that it makes lots of reliable power, in a compact proven lightweight package that is affordable! That's not the case with the toy straight 6

Depends entirely on your goals. While the LS motor is compact and lightweight, it's also wide and a V configuration motor meaning it can be difficult to turbocharge in a cramped engine bay (not to mention heat management because of the piping if you're going single).


Also, going NA-T on a 2JZ-GE is dirt cheap, and has been done for years reliably. Much cheaper than the LS swap at that level. Full GTE swaps are where the money is, but you can sell the stock twin turbo setup for a decent amount of money to even it out.


But wait, I'm talking to a V8 fanboy, so this is going right over your head...

[ZDan]

Originally Posted by Poodles

Yes, 7, 2 bolt mains that hold more HP per cylinder than the LS1 can with 6 bolt mains...

I hardly think that comparing these two engines defines how much power a cylinder can hold with 7 2-bolt mains vs. 5 6-bolt mains.

Love the logic here:
Engine you like has 7 main bearings. Engine you don't like has 5. Therefore 7 mains is inherently "better" than 5.

Engine you like has 2 bolt mains. Engine you don't like has 6-bolt mains. Therefore 2 bolts per main is inherently "better" than 6.

I guess that the 2JZ would be even moar betterer with 12 main bearings with 1 bolt each!

OBVIOUSLY a V8 has 5 main bearings because having a bearing between each rod would make the engine a lot longer and heavier without giving any real benefit. Which is why you don't find any V8s with 9 main bearings. It would be stupid. How many F1 v8 engines had 5 main bearings I wonder? My bet: All of them.

It is perfectly absurd to say that an I6 having the logical number of 7 main bearings is "better" than a V8 having the only LOGICAL number of main bearings: 5.

Regarding number of main cap bolts, I don't see why having 2 or 4 or 6 is a big deal. The main caps are designed to hold the crank stable over a range of rpm and power levels with some margin. However they achieve that is fine with me. Of course a V8 crank will see large loads in the planes of the cylinders, which are at +/-45 degrees, whereas an inline engine has primarily vertical forces. Different engine architecture, different main cap solutions.

Again, you don't know what you're talking about. There is a support for each rod on both sides while there is support for each pair on a V8. If you want to talk about "needing," the LS motors need 6 bolts to hodl the mains in place while the 2J does just fine with 2.

See above. Obviously, adding unnecessary length and weight to a V8 is dumb, which is why no one ever does it.

Straight six is the strongest engine design, there's a reason any serious diesel motor uses that configuration.

For me, "like a diesel" doesn't necessarily imply suitability in a sports car. I want reliable power in as small and lightweight a package as possible. Inline 6s are cool and I love them, but they are not necessarily ideal for small/lightweight sports cars, though PLENTY of great sports cars have been *built around* I6 engines. IMO far from ideal for a swap into a car built around a very short H-4 engine.

The 2JZ is much longer and heavier (ensuring inferior F/R weight distribution for a swap in an 86) and has a higher c.g. than an LS engine, with no advantage in terms of power potential.

Depends entirely on your goals. While the LS motor is compact and lightweight, it's also wide and a V configuration motor meaning it can be difficult to turbocharge in a cramped engine bay (not to mention heat management because of the piping if you're going single).

Personally, I don't think the 86 is a good candidate for either swap due to F/R weight distribution issues, but for sure the LS would be, *for ME*, a more logical candidate.

For others, maybe not. Which is fine. But don't pretend the 2JZ is "better", it's just another set of different compromises.

[Sideways&Smiling]

it really depends on what you want to do with the car... if all you care about is drifting, drag racing, or doing burnouts to and from work regularly, the 2jz adding extra weight isn't really hurting anything.

But for autocross, time attack, road racing, etc. weight distribution and balance is much more important...

[Reaper]

Car has better weight distribution with an ls than it does with an fa20. Already been proven.