Turbo or swap
 

Hi,its better to do turbocharge fa20 for about 350hp (on 93 octans-in my lifeplace I can't buy better fuel) or make the 2jz/LSx/other jdm engine swap?
Thanks for answers :)

Turbo 100%. I'm at about 330whp at 15psi, stock engine. 93 octane

How much torque did you get? And how about
gearbox/transmission?

It all depends on your goals. If you plan to heavily track the car then a swap might be better than the alternative. If you won't ever track the car and you will be fine with 350hp or less then just add the turbo. 350hp is doable with a turbo, but you will be pushing it on 93 octane.

The alternative: you could build the motor with lower compression to meet or exceed that figure for pump gas, but anything greater than 300tq and the transmission will go, so that is your next ceiling; you either need to build the tranny or do a swap to a CD009 or something.

This is why some prefer the swap because the cost to build the stock motor and swap the tranny and buy a turbo kit might approximate the cost of a budget swap, and the swap could have better reliability with more power and/or power potential. If you are heavily tracking the car, for many, this becomes a no brainer, as the reliability of even a built motor on track is dubious.

Alternatively, swaps are rarely worth the time, money, headaches, etc unless the car will be pushed on track and/or be seeing 450whp+ type of figures. I don't know what your limitations are with acquiring parts for a swap in Poland or if there are emission concerns or if there is a desire to have full CANBUS integration or just a running car.

I just want to add that I want to get about 350hp and how I know I US you use whp.
What will be The cost of making 350hp with brakes nad transmission upgrade?

The stock gearbox is rated at around 175tq, but it will usually hold more than that. 250tq is the limit for the track and pushing it for the street. 300tq is the max for the street. These numbers are ballparks and vary greatly with driving style and other factors.

Hp is measure from the factory. Whp is measured with a dyno, so it is more relevant to discuss whp, but estimating engine hp from whp works too.

If you are just wanting 350hp then a turbo kit with a clutch kit should be fine on the stock transmission unless you are beating on it often or tracking the car. The simplest transmission swap is to buy the Maxworks CD009 swap kit ($6k), and the cheaper route is to do a similar swap yourself with used parts.

If you want better brake performance and brake feel for the street or for autocross then upgrading pads, fluid, lines and a master cylinder brace is enough. If you are tracking the car often then you would want to consider a big brake kit to conserve your pads to save on money and to potentially avoid brake fade.

The stock internals will hold this Power? And What turbo should I use? Have I to put wider header gasket? Sorry for that questions but on Polish forums cant find any informations

Generally speaking, 350whp is considered the safe limit for the rods and 300whp being the safe limit on pump gas, but some people push things.

Many turbos will get you there. The difference will be in size and features like ball bearing versus journal bearing, or single scroll versus twin scroll.

Adding a thicker head gasket isn't an option on this motor without adding more money and problems to the equation. If you thicken the head gaskets then the turbo manifold and intake manifold may not line up to the holes on the heads, as they will be further apart. If you want to drop compression then you either need to do a built motor or you would have to play with the valve timing to alter the effective compression ratio, which isn't really done (as far as I am aware) outside of factory tunes.

Torque is what breaks things not so much hp. Although hp is equated from torque.
But 240wtq is pushing the limits of the stock rods especially for track use. Which 240wtq at 7000rpm is 320whp. The other thing that breaks things is a quick fast hit of torque at low rpm 240wtq at 3500rpm vs 5500rpm is a big difference better to gradually build up the torque then get hit by it all at once down low so choosing a setup that has lower low-mid numbers would help longevity. Some people have pushed a lot further but it becomes more and more risky. Also revving too high isn’t good either.

The stock trans is rated 180ft lbs. mostly because the clutch. After a while beating on it stock clutch wont hold up long. Once clutch upgraded the physical gears become questionable at about 240wtq.

Heat especially on a turbo is another issue. Oil cooler and hood vents at a minimum.

With this new power brakes need upgrading, suspension would be good as well. Wheels/tires for sure. Although same issue with a swap.

Another thing to factor is power to weight. 2750lbs at 350whp will have similar acceleration to 2550lbs at 320whp. Although better handling/braking being lighter. Weight reduction goes a long way on these cars and may help reduce your desired power needs.

Transmissions aren't rated based on the clutch. Our Aisin transmission has an Exedy OEM clutch. Two different companies with different ratings. Maybe you meant something else, but that is how it reads.

He lives in Poland where the latitude is similar to Canada. I think an oil cooler and hood vents might be overkill, especially since he hasn't specified track use. The WRX/Forester OEM oil cooler/regulator is probably enough, and if he is doing track days then he is probably fine with a thermostatic oil cooler, but could over do it with cooling easily. I doubt hood vents are necessary, but a turbo blanket, ceramic coating and/or header wrap would probably be better advice than hood vents.

Brakes don't really NEED upgrading, as I mentioned, unless tracking the car. OEM brakes are fine for the streets. Bigger brakes only manage heat during repeated cycling. For the streets, big brakes, and even better pads, do far less to stop the car than a set of good tires, which was better advice.

The trans is rated at 250nm / 184ft lbs from manufacturer (https://www.aisin-aw.co.jp/en/produc...lineup/mt.html) what that means precisely I'm not 100% sure, but many peoples reported excessive wear and slippage of the clutch at about 180wtq and the general consensus I’ve read across several threads on this forum and a few other forums is gears start to shear at 240wtq although individual experiences differ as well as driving habits and conditions. And 2-4 synchros are all over the place for what power they are going out. So personally id get a clutch if going over 180wtq, and don’t go over 240wtq after clutch upgrade if you want any hope for it to last. If you want more then do the trans swap.

And for some reason I thought i read he was planning to track the car but rereading i guess he didn’t mention it. So you are more or less correct about the other stuff if its not seeing a track and just a DD.

Yeah, I said earlier the stock transmission is rated to 175tq roughly, but yes, 184 is more exact. The Exedy Stage 1 clutch is rated to 203wtq wheels or 254tq flywheel. Exedy's Stage 2 clutch is rated at 228wtq and 300tq, respectively. I would guess that the OEM clutch might be somewhere around 200tq to the flywheel, but regardless, the OEM clutch can hold more than that without slipping, but its life would be seriously reduced. Just arguing the finer points.

I'm over 203wtq with a stage 1 Exedy clutch, and my clutch and transmission is still holding. I'm probably at the 240wtq mark based on the Delicious tune Harrop kit with E85 at 12psi and again, my clutch and transmission is holding. Of course, a turbo will hit that torque lower in the rpms than my car, so that is a factor he should consider. Good thing our transmissions are cheap to replace.

Some engines won't hold stock power. The tune, and how you use the power is critical to your longevity. I feel comfortable with my stock transmission and Stage 1 Exedy clutch becuase I know I have an excellent tune, and made sure to keep torque low beneath 3500RPM- I also know better than to induce high load at low RPM (I don't floor it in 6th gear on the interstate for example, I'd go down to 4th gear if I wanted to move)

I feel that if you just want some extra power and want to keep longevity, you should look into a centrifugal supercharger; they build boost with RPM and generally are less prone to issue. :burnrubber: