Since this thread is basically dead I may as well ask, what holds the FA20 back in NA form? Is it the heads?

There's a reason why Orido replaced his Toyota/Lexus V8 with an LS engine.

- the Lexus V8 constantly blew (more than 3x?) even though it was built with aftermarket pistons and rods and had power and tuning problems
- the LS is more reliable, even in stock form
- the LS is simpler and has less parts..therefore less maintenance
- the LS weighs 125lbs lighter than the Lexus V8, yet makes much more hp and gobs of torque, even in stock form
- and so on....

As much as I am bias towards and love Japanese cars and other Japanese stuff, would like to keep it Japanese engined, and also really dislike domestics... The LS is simply a better engine and the smartest decision for a swap.

This is a great little car with a over engineered weird engine with a ton of moving parts. This car just screams for a transplant if you got the time/money or inclination.

It's the weak flux capacitors

I've heard rods and rod bearings might be suspect for mechanical and then there are some oiling issues as well.

You can also fit 285s under the stock rear fenders... no rub, no pull, no roll, no prob ;) (proven by Crawford and 1 other ft86 member on his black FT iirc). 265/285 or 275square should give sufficient/decent grip for an LSx engine...and also at the same time much much more tire options (cheaper too) than +300mm tires. RS3, DII, RE11, AD08r etc all come in 285s ;)

I think FOOD was citing the 55kg difference between the LS and 1uz engines, not the FA20 and 1uz.

Yeah 1UZs and LS1s weigh about the same around 430 to 450ish pounds in running condition. I have heard some people quote around 390lbs for a 1UZ, but that might be with no fluids and stuff.

I think the main draw to the 1UZ is the price, they are dirt cheap, you can find them on ebay for 500 bucks no problem. See first result to come up! Not to mention it being fairly strong while still being very cheap.

The saving grace of the FA 20 engine is the height: this lump is a lot shorter than an average upright inline-4 or V-configuration engines, with the bulky DOHC cylinder heads sitting very low down in the chassis. That is all this engine does add - a lower center of gravity. But low weight isn't what this unusual engine layout offers, not hardly. As you can see below, we've already weighed the stock FA20 engine and transmission at 480 pounds. This is, by far, the heaviest 4-cylinder aluminum engine we've ever weighed.

http://vorshlag.smugmug.com/Projects..._DSC7750-L.jpg
Remember the 480 pound measurement of the factory FA20 and 5-spd, shown above? Well a Tremec T56 Magnum XL is 128 pounds and a factory LS6 weighs 457 pounds, with a lighter than stock flywheel (which we always do - it doesn't need a 48 pound 2-piece factory flywheel, even for street use) plus the heavy OEM exhaust manifolds and a power steering pump. This 86 chassis has electric assist power steering built in the steering column, so we will remove the hydraulic power steering pump from the LSx engine we end up with, and our exhaust headers always save weight over OEM cast iron manifolds. After we do the math it looks like it is going to be pretty close to the stock weight, which is good. The weight of a turbocharger and intercooler from our before weight here is not insignificant, either. If we're wrong on that guess, we'll show it here, too. Look for the final weight of the FR-S once this V8 swap is done, which we will compare with the "before" weight.

Why is this subaru motor so heavy?

I feel bad for OP. He put a lot of work into that first post.

I didn't make it up...just meant that Orido said it himself in his YT video (that the LS7 was much lighter than the Lexus V8...55kg iirc). Tell him lol.

Regardless...a Lexus V8 would be the worst choice. It's not exactly a popular engine with a lot of aftermarket support, nor are there many people with experience and knowledge with it that can help, etc. And getting it rebuilt and also getting parts for it would be specialized and hard to get/find parts from Japan. Not worth it. Also can't get a shiny new crate engine if that's what you want. Iron too I think...and so on and so on. Anyone who swaps in a Lexus V8 is a straight fool lol.

LS7 is going to be lighter primarily because it's not DOHC.


Not a ton of aftermarket support I can agree with (at least compared to say a 2JZ or LSx). Plenty of people know what to do with the motor though. Normal rebuild parts are easy to find. Iron? It's all aluminum like the LSx and runs 6 bolt mains.


It's a nice motor, but like I said, too small displacement wise for the amount of effort needed to swap it in.

It belongs in a Lexus luxury sedan and nothing else. That car was never a highly modified car in the aftermarket world for engine mods; only lowering it and stance at most. Compared to any other popular engine - LSx, RB, 2JZ, even Honda B series, etc...those engines have always been popular in making faster. Aftermarket and experience is close to nil and always will be for the Lexus V8. There may be plenty of people that know what to do with them..but in this case, "plenty" means maybe 10-20 people on earth lol....compared to thousands of experienced people for other engines. Going Lexus V8 is just not a wise decision at all (from both a budget/money standpoint as well as a performance standpoint) and people that swap them in are just trying too hard to be unique, different or "cool" ...just the truth.

Apparently you don't know the history behind the motor as it was designed after racing motors and was supposed to be used for racing. A twin turbo variant was used in their Le Mans MR2.


Also, as long as you know piston driven engines, they're all the same. There are very few "tricks" between any different layout, so anyone that could build an LS motor could easily build a 1UZ.


I agree on the cost standpoint based on performance, at least until a 1UZ swap became a bolt in affair in this chassis. It's nearly a bolt in to a MKIII Supra chassis and I still didn't go that route because the exhaust manifolds needed are hard to find, and I'd still have to have a custom exhaust made.

It is nice to see some engine swap ideas and especially the diversity of ideas in this thread. I'm not looking for an FA20 replacement but rather a 3RZ replacement for a PreRunner.