Should I supercharge it?

So, I need moah powah, but I can't decide which way to go.

I've been following this thread for a while with curiosity: http://www.rs25.com/forums/showthread.php?t=97081


It's a Raptor SC kit for NA EJ25's (http://www.raptorsc.com.au/kits.php?id=20) for like 5psi non-intercooled or 6psi water-to-air intercooled with piggyback EM (Moristech ProSequential? Are they well known?).

Prices are in Australian dollars, so cut them by about 40% for US dollars (for a limited time only! Good exchange rates FTW). So, the non-IC 5psi kit is like $2500 US and the 6psi IC kit is a bit over $3000, IIRC.



Opinions?



This appeals to me because its a lot less work and potential problems than doing a motor swap, and I think the gains might be enough for me (whereas just doing like cams wouldn't be enough).

I'm very aware that I could blow my motor up on day 1 by boosting it, but this appears to be as safe as a guy could get boosting a EJ251. Am I wrong?



For guys who know more than me (most everyone here, lol) - are there things about an SC setup that I might dislike on a daily driver?

 

If i recall your car has a front Air/Fuel Sensor which is what the ECU runs off. NO Piggy back should be able to go around it. Ive tried a few with mine and EM.

 

subaru and piggyback dont mix, they will learn around them. and for that price you might as well do a swap and make far more power.

 

Oh and expect maybe 150-170 whp.

 

Weird. They seem pretty confident that they're doing it right.

A tidbit from the ProSequential site (http://www.moristech.com.au/pro-sequential-interceptor.asp):

I don't know too much about tuning, yet. I certainly wouldn't want to go this route if there's such a glaring hole in their design.

Seems odd that they wouldn't know that, though. Their test bed is an 05 Impreza.

 

I was thinking some cams, too, and some custom tuning if anyone around here can work with that ProSequential (can they?). That oughta net me more maybe? Cause 150-170 isn't a whole lot for that kinda $$.



Of course, I may just be way off. Which is why I'm passing this through the MNSubaru sounding board.

 

Its your money, with that low of boost it probably will last a while, but its all in the tune.

 

But you think I may be disappointed in the performance it being only 5 or 6 psi (though I'd have the higher NA RS comp ratio, but that hardly makes up for another 10-20 psi, lol)?


I'd hate to drop a few g's and have the car still feel too slow, which is why I'm seeking out your guy's opinions.

And there's not a lot of people supercharging Subaru's it seems, so I at least want to make sure this isn't just a really stupid idea.

 

I have thrown alot of money into my car and its custom Turbo setup. But some how i feel that supercharger kit will cost much much more...

 

As in you literally spent a lot less on your setup, or you think there will be unexpected costs with it (like blown up motors and a system that can't be resold if it sucks?).

It does seem a little too simple, so I'm wondering what the caveat is?

 

IIRC, the same issues were encountered when Rimmer tried to use the kit for the '98 on the '99. As soon as positive manifold pressure was encountered, the ECU freaked out. The MAP sensor was pinned at a hair over zero manifold pressure.



Keep your wiring system, and get a G4 Storm. Then you can do whatever the hell you want.

 

I think what Brian is trying to say is that to get what you want out of it, you are going to have to spend a fair amount more than the $2500 cost of the 'kit'. I've spent more than the cost of that kit on just my ECU and datalogging equipment.

 

I was like you at first didnt want much more then 5psi of boost. But i shortly grew to me wanting more. At 10psi it(the motor) lasted about a year. I think buying the supercharger will limit you to just that in power. With a turbo swap you can have endless amounts of gains.

 

Yeah - I hear that.

Seems that anything other than a swap leaves me very limited for future upgrades. And something like this might be really tough to get money back out of if its not enough.


What about the EM they're setting this up with? I get the feeling you guys think it'll be crap? And that I'd still likely need more EM work, possibly even a entirely different aftermarket ECU, to make this really reliable and get most of the potential out of the system?

One of my enticements was the lack of ancillary costs, so if it would need new EM right away, it would be no longer very attractive to me at all.

 

Part of my consideration, too, is my ability and my impatience.

I see something like this and say, "Geez, I could install that - nothing to it."

Then I look at doing a motor swap and say, "Holy crap, that's a scary huge project involving quite a few things I know nothing about and some things I do but will undoubtedly take way more time than I expect."


I could actually have something like this on my car by spring, but a motor swap seems quite a bit more out of reach.


But, I learned a bit of a lesson on impatience recently with my suspension upgrading. I am trying to think this through and weigh my options more carefully - the costs and risks are of course much higher.

 

on a sohc you could do a swap with the motor still in, it would be a pita and you would need a hoist though. Ide pull the motor.

 

I'm not quite so naive to miss that point, Russ.

Honestly, I get that. I really do. It's why I continue to lean towards wait and swap even though I look into other options like this.

Even if everyone told me that the SC kit would be safe and fun and do everything the guy selling it says it will (and no one is), I'd still have to carefully consider if I was okay with that being the end of the road for power upgrades without spending major $$ and basically starting over with a new plan.

 

just put an H6 in it and call it a day..nuff said

super chargers are nice and all but with that money..invest in an NA H6..youll be up in the high 200 range without turbos and anything like that...if you decided to turbo it..youd easily get 300 to 400

om nom nom

 

Just do a swap and be done with it.

 

lol. Sexy sounding, but ... That's way beyond what I want to do. Cost, effort, etc. Way beyond what I want. Seriously, I wonder if 400hp would be too much.

It really just always comes back to this, doesn't it. Even more so since I doubt the tranny I'm running will hold up long under much more torque.

If a decent deal on a donor WRX came up I'd probably dive into that route, but nothing has presented itself yet and I haven't really looked too hard, yet.

 

yeah i agree with wall..doing a swap is probably the best way to make power...hell build your own block with forged internals like timshow was doing

 

Yeah, definitely.

Basically when you think about it, you can spend $3-4g to supercharge your car to make nearly as much power as a stock WRX -- with the added "benefit" of uncertain reliability to both the motor and the transmission.

Plus, like what Russ said, you have to look to the future. A swapped car will certainly give you much more opportunities down the road. Also add in the fact that swapped gc's are pretty dang hot, imo. :biggrin:

There are plenty of people on here whom I'm sure would help out with a swap project.

 

i want to know where Russ finds STIs for 6k or less

 

timshow > me


Frakenbuild sounds fun and all, but um yeah - I've never seen the inside of an engine. Not sure I'm up for assembling one and dropping it in my car.

It's still on my list of possibilities - custom build - but with the falling prices of WRX's (book less than my older RS is some cases, lol) a swap seems more manageable.

If I have a whole wrecked WRX to take parts off of and a maybe donor RS wiring harnesses to get a head start (though ECS is having a harness merge sale currently, too), I think a swap could be doable.


I do have a bonus, raise, tax return, and increased credit limits all falling in my lap right now. :naughty:

 

Not even swap would have to be in order.

Turbo X-member
257 Shortblock.
TD04 Turbo
Up and Down Pipes
Cat Back Exhaust
Engine Management

 

i have learned by doing...pulling apart an engine is probably the most educational thing you can do...

 

Seems more economical to swap. Not necessarily?

I would just be concerned about lots of little bits and pieces here and there that I'd be missing/forgetting and endless runs to Morrie's for more little parts, etc.

257 shortblock - that would be heads, too, yes? Or no?

Price new on all that w/ 20% discount? :biggrin: (j/k)

 

Shortblock is the block and rotating assembly. No heads or ancillary devices.




If you went Brian's route, it is easier, IMO. You don't waste a bunch of money buying a whole car, and then have to sell off all the stuff you don't use.


If you got a standalone, like a G4 Storm or equivalent, you can keep the wiring you already have, and can do whatever you want down the road. No harness merging or any of that business.


There will always be little stuff. Even if you have a donor car, there still is LOTS of little stuff.

 

Nos!!!1!

 

if youre looking for more power do EXACTLY what bilk has done with his rs. get a standalone, (he is running a hydra, which is simply plug and play) then pick up a ej257, a crossmember and random turbo parts such as exhaust, which I would reccomend picking up used to save some cash.
frankenbuilds are fun, but nobody wants to trust frankenstein to get you to and from work reliably do it right the first time, **** the supercharger.

 

Right - so bolt a turbo-able bottom end in between my heads, throw on a turbo and the exhaust to drive it (IC? didn't see that in the list), and some custom EM.

That's a plausible option. I may have to look into that more to see what's really all involved.

no thx

 

nobody said injectors and pump?????

 

Probably depends on how big of a turbo I'd run. Right?

Stockers ought to be fine for, um, stock-ish WRX or even STi like setup, no?

The supercharger guy is saying stock RS injectors are fine for that application.


Besides, that sort of thing is sort of tangential to the whole, "What route should I go" question. It's not a huge expense and a known potential need.

 

Plan a week with out your car and pull the motor. Then make a list for the important things. Its all pretty standard for gaskets.

Shortblock No heads. Your 251SOHC heads are just fine.

New 257 Shortblock = $1764

 

if youre gonna do it, get EVERYTHING you need and do it in a weekend (its very possible) send it off to ronnie on monday for a tune and there you have it! you have to also consider the transmission you are using isnt going to hold any power, I would upgrade that first, with an 04+ box. then from there start tackling engine stuff.

 

the stock injectors offer NOTHING into boost. at least thats what I learned when tuning snowbums car.

 

I was able to run good power on STOCK WRX blue Injectors at 10PSI. I have a set if need some.

 

dont forget to mention they fit into the rs rails fine with bigger 0 rings!

 

Swap.....get a standalone em with a ronnie tune. Hydra makes a plug and play em for the RS, should be the most expensive AND ESSENTIAL component you buy. Dont be like me and blow up a $900 block because, like a meth head your running too lean and pluck your face off.

If your on a budget pick up a used 22t shortblock or ej257 take it to the machinist with a .020 overbore piston and get her bored/honed. Also, have your rods/pistons/crank inspected and balanced....there could be a burr on them crank journals and you wouldnt know it until 50miles in and metal shards F*** up your newly built engine.

slap your heads/intake manifold and others on it w/ the forged pistons, sti rods and acl/cosworth/oem bearings. BINGO BANGO

Dont forget turbo/xmember, ect....all that was mentioned.

I honestly think you would run into more problems supercharging your car rather then swapping a turbo setup on. Lots more custom fabrication with the supercharger setup.....jbstick and duct tape?

O, and that cable tranny will have a hard time holding all the power....

 

Of course injectors and a fuel pump. And ya, IC. Those things are a given.





A weekend would be stretching it, unless you had a lot of experienced help on hand. Even so, it depends on wiring. You aren't wiring in a standalone in a day. Not gonna happen. Unless you totally half-ass it...




Take your time sourcing parts, and figuring out what you need. I spent years doing that before I started installing hot rod parts. The more time you spend getting a plan together, and talking to people who have done it before, the less money you waste, and the less time your car is down.

 

F*** the stock 2.5rs fuel rails, the fpr's location interferes with the turbo's location. Pick up something aftermarket and save yourself the trouble of modifying them....or wrx heads/intake/fuelrails.

 

Good advice from all, definitely.

All this here and there stuff - like stock rs fuel rails in the wrong spot get wrx ones point to swap rather than build.

And I'm the kind of person that if a wrecked WRX that hasn't been totally raped presents itself I'd be likely to just swoop it up and run with it - I personally get much more **** done in my life by proceeding a little recklessly (quickly) at times.

Tranny's a big factor, too, and leans me toward swap assuming I can land a wrecked wrx/sti that hasn't had the tranny pulled first. I know mine won't hold forever or take tons of power.


Snowbum, custom fab work on the SC is all done with the kit, that's part of the appeal. No brackets or anything to fab. But the opposition to that idea seems pretty strong, for good reason I'm sure.

You guys have all but talked me out of the SC idea at this point. lol


Thought I could cut some corners, shell out extra $$, and have something pretty decent, but now I'm thinking its a heck of a gamble EM-wise and constrains my possibilities (engine blows, then what? stronger rotating parts in the same EJ251 case with the same 6psi SC on it - that's all without scraping and starting over).


I'm past the whole turbo-spool sucks, less displacement, no low end torque, and all those blanket anti-turbo ideas. Didn't take more than a couple of rides in other member's cars to sell me on FI.

Now it's all about what can I get done on my budget (which is decent now but not endless) and get done within a time frame that my perpetually impatient self can cope with.

 

^ That's a lot of dough to shell out just because the FPR is in the way. Usually one can run a 1/4 NPT tap in the FPR end of the rail and use your own regulator. Like this:

 

I did something like that but with a flange off of an old fuel rail and I clamped a hose to the outlet. FTW!