USDM STi motor in SVX

[listed]

Anyone know if the 2.5l STi motor could be swapped into an SVX? I was planing on buying a supra, but with their current astronomically inflaited price, why not improve upon a car I already have. I'd budget around 12k for a 400hp svx if it could be done. I just can't figure out if it would be best to plant a different motor in there or have a lot of custom fabrication done to turbocharge an eg33. Does anyone know of a current lower compression forged piston on the market, a stronger crankshaft, cam-belt, valve, valve lash adjuster, or more aggressive cam? I'd likely use an STi 6 sp. transmission, but would have to have the rest of the parts fabricated. And then there's the feul delivery issue. If there are others out there explore any of these options, please post.

Chris

[mbtoloczko]

Originally posted by listed
Anyone know if the 2.5l STi motor could be swapped into an SVX? I was planing on buying a supra, but with their current astronomically inflaited price, why not improve upon a car I already have. I'd budget around 12k for a 400hp svx if it could be done. I just can't figure out if it would be best to plant a different motor in there or have a lot of custom fabrication done to turbocharge an eg33. Does anyone know of a current lower compression forged piston on the market, a stronger crankshaft, cam-belt, valve, valve lash adjuster, or more aggressive cam? I'd likely use an STi 6 sp. transmission, but would have to have the rest of the parts fabricated. And then there's the feul delivery issue. If there are others out there explore any of these options, please post.

Chris

I've thought about this too. The SVX motor, without a doubt, is sweet, but I don't think its as tough as the STi 2.5l motor, even with forged pistons, etc in the EG33. Plus, there's going to be way more aftermarket for the STi motor. Just swap in the STi motor and an STi tranny, and you have 300 HP right off the bat. Toss in a bigger turbo, etc, and you'll be up to 400 HP in no time.

[TomsSVX]

what he wants to know if it would be a feasable project w/ 12grand. I think so, but you wil need some serious fabrication and a wiring nightmare, if you strip out the svx completely of the 3.3 equiptment and replace w/ sti stuff it should be reasonable, aslo there are millions of aftermarket upgrades for the sti so please let me know what u want to do because this is freakin sweet project

[SVXtasy]

Tell a good custom fabricator that you want a 400 hp and you have 12k. With out any problem there would be people who could do it. Talk to http://www.rallispec.com/ about it they might have some good ideas and with 12k they might do it. They would know about an EG33 build and if the 2.5 STi is a good idea.

[mbtoloczko]

Originally posted by tomssvx
what he wants to know if it would be a feasable project w/ 12grand. I think so, but you wil need some serious fabrication and a wiring nightmare, if you strip out the svx completely of the 3.3 equiptment and replace w/ sti stuff it should be reasonable, aslo there are millions of aftermarket upgrades for the sti so please let me know what u want to do because this is freakin sweet project

If I reread his post, it seems to me that he was asking opinions on the ideas he presented. I don't see anything about him asking specifically if a 2.5l swap was possible with $12K.

I wouldn't imagine that wiring up a 2.5l in an SVX would be significantly more difficult than it would be to install an aftermarket ecu in an SVX/EG33 turbo project. The only major difference would be dealing with the drive-by-wire throttle for the 2.5l STi motor. In some ways it would probably be easier with the STi motor because places like AEM will soon have versions of their ecu made specifically for the 2.5l motor, so it would take much of the footwork out of deciding which inputs to use, and the ecu would have a 2.5l map already installed. Not having to flesh out a base map would be a huge time saver. The more I think about it, the more a 2.5l swap sounds like a better idea than doing an EG33 turbo.

[TomsSVX]

the eg33 turbo is restricted by the stock compression. Yes there are pistons you can get to compensate but is it worth it? a single turbo eg33 making what the most 400 hp or just taking a 2.5l and just cram it full of aftermarket parts and make more than an eg33. I dunno this is all my opinion, i love the eg33 so i will stick to it.

[NomadTW]

ahem
*cough*dunebuggysupercharger*cough*

[UberRoo]

Has anyone ever broken an EG33? I mean the pistons, rods, crank or anything like that? I really wonder what they can take just the way they are. Anyone know, or are we just guessing?

It seems to me that all the EG33 really needs for low boost, is boost itself. For medium boost, some pistons. For large boost, rods would be a good idea. I get the impression that the crank is pretty stout. If I was really worried about it, I'd drop the rev limiter a few RPM. Compression ratio is of course a consideration, but even with the factory compression, a tiny amount of boost is possible. Once you start upgrading parts, the compression ratio problem is resolved.

You should be able to get a set of custom pistons and rods for under $1500. Throw in a used compressor for another $500, and you've got all the parts. Next comes the fabrication, a fuel injection system like MegaSquirt, an ignition system, plumbing, and...well, probably something else. But my point is that aside from the time and labour of fabrication, making the EG33 push big numbers should be pretty straightforward and not terribly expensive. Am I missing something? (Besides a stronger transmission.)

Why the 3.3 litre, and not the 2.5? Okay, say it with me: D I S P L A C E M E N T

Let me throw my two cents in...


A brand new complete STI engine assembly w/turbocharger would run you about $6,000. So for 6 grand plus a $500 ECM, plus custom fabrication you can add 70 HP and 73 Ftlb torque to your SVX. That sounds expensive. You'd spend a lot less just beefing up the 3.3 to produce another 70 HP.



Dave

[mbtoloczko]

Originally posted by red95svx
Let me throw my two cents in...

A brand new complete STI engine assembly w/turbocharger would run you about $6,000. So for 6 grand plus a $500 ECM, plus custom fabrication you can add 70 HP and 73 Ftlb torque to your SVX. That sounds expensive. You'd spend a lot less just beefing up the 3.3 to produce another 70 HP.

Dave

Very true. But if the goal were 400 HP+, I'd bet it would be easier and less expensive to install the STi engine and a larger turbo. That combined with an optimized a/f/spark map would probably get 400 HP. That would be much less work than doing all the custom fab necessary to build up a turbo or SC on an EG33.

[oab_au]

Originally posted by mbtoloczko


Very true. But if the goal were 400 HP+, I'd bet it would be easier and less expensive to install the STi engine and a larger turbo. That combined with an optimized a/f/spark map would probably get 400 HP. That would be much less work than doing all the custom fab necessary to build up a turbo or SC on an EG33.

But what would do for torque below 3000 RPM. You would not have that large lump of torque, provided by the IRIS, that runs from 2200 to 4000, and supplies that big push about 3500 RPM.

You would need lower gearing and 6 speeds to spread the torque. No more torqueing around at 1500 RPM in top.

Harvey.

god this would be an amazing car. i really hope that you do the engine swap and get that pushin more than 400hp cause that would be awsome.

[TomsSVX]

anyone w/ cash to blow can make 400+ out of an sti motor from aftermarket parts, the problem with making this with an eg33 is the fact that there is no market for parts for our cars. Nitrous is the only way to get good gains with little money. Take 2.5t and build it up done probobly making round 450hp with bout 3 or 4 grand of work to a motor that you could pick up used for bout 3-4 grand then have money left over for the fabrication to make it work in our cars. No argument, make an sti svx instead of juicing an eg33. If you want low end torque get the right exhaust so the turbo spools quicker. You could never make the power of an sti motor with the eg33 with the same money to power ratio.

[GreenMarine]

I absolutly agree with tomssvx... Besides if any of ya have driven an STi or a Forester XT then you will understand that these engines are WAY more powerful than our EG33... Don't get me wrong, I love the EG33... And I'm not gonna do any more mods tward more power unless my engine goes ( I doubt this will happen )... But if it does, Forester XT engine here I come ... I've driven a Forester XT and I can say that the acceleration is nothing short of SHOCKING!!!! I believe that that engine would be a great starter for our cars... Sure an STi engine would be awesome... But everyone and thier mom will be out to get an STi engine... Seems that lots of people over look the forester XT engine... It is prectically the same thing!!! Only diffrences being tuning, cams, turbo, intercooler, exhause and intake ant that is about it!!!... But it still puts out amazing power!!!!

[cdigerlando]

I would like to point out that the STi pistons are not forged. This was a misconception. I hope that this is not the case with our SVX pistons, and that it is not just a misconception. If you have doubts, check the nasioc forum. There is heavy discussion about this. The STi deck is semi closed. The ultimate power capability is unknown.

In speaking with the varous sources the SVX engine has made 400+ on race fuel with a turbo (injectors too of course). This was used in a race car and was very reliable too. They were concerned going over this HP though.

So....the 2.5 l option would probably be great, but I think it would be a bit more to do than the SVX modification. Not so much from the standpoint of the engine costs. More from the tranny costs. I think then it depends on what kind of a deal you can get on a drivetrain. If you bought it from subaru, I think it would be more expensive. I have heard of installed costs for a new STi tranny in a WRX to cost upwards of 8,500 +. Alexumm got an incredible deal! He could benifit from an engine swap at this point.

I think the best route to go would be stand alone engine management. That's about 2.5k. Add that to the engine cost, and then the installation and mount fabrication. Then figure out how to run your AC and such with the factory ECU.

Bottom line I think is that if more people were interested in dumping money into these cars, the cheaper a stock engine modification would be. But history shows that SVXers don't tinker too much with there engines. And the ones that do, like me, are not that good at it.