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I am getting ready to turbo my RS and want to know if anyone has heard of any problems with weak pistons... or anything else I should know about before I go through with this...
 

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Yes. The valve reliefs in the pistons are a weak point. I have seen a couple of NA 2000 models that have broken those pistons. You should contact Bill Cook. He blew a piston on his 2000 RS when it was turboed.

William Cook

[email protected]
 

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James, the largest problem with the 2000-2001 pistons is that they are 10.0:1 compression, which is relatively high for a turbo application. Now, if the pistons were forged, it would be a different story, as forged pistons have a higher tolerance from things like detonation and pinging due to their stronger design. The pistons in out cars are cast, which is recipe for a weaker piston.

Alas, look at the 2.2-T engine, a lower compression piston, but not forged either. As you can see, if the engine is tuned right, then there isn't TOO much to worry about. But, then again, this depends on how much boost you plan to run. I personally will not run anything more than 6 psi on the stock motor, no matter how rich my A/F is.

I think that my advice to you is James (considering your at 6,000 ft.) don't run any more than 7 psi and you should be golden, just remember to keep a slightly rich mixture and get TIMING CONTROL!!! I can't stress it enough considering the disgustingly huge amount of advance our cars run. I personally am running an Apex ITC and a J&S Safegaurd.


Graham
 

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Okay, that is what I thought. Then I am definately going to get new pistons and rods. And I'll lower the compression ratio some while I am in there. Maybe something like 8.5:1 or 9.5:1. I still want around town torque you know... :)

I am probably going to get an entire PEM like the SDS EFI or TEC-III (if it's available yet) so I don't have to worry about blowing things apart.

Thanks for the info guys, I appreciate it.

Graham, I'll be putting your PFR mod up within the week. Thanks!
 

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James, now depending on how much boost you want to run you may not NEED new pistons, but piece of mind having them does make a difference. Like I said, there are guys who have run conservative (3-5 psi) amounts of boost on their stock internals for many many miles, you just can't get carried away.

New pistons and rods would be beautiful, but get ready to pull out the wallet. New rods will run you anywhere from $500-$700 a set, and pistons anywhere from $600-$900. Not to mention you will probably have to have the bock or pistons machined to get them to fit, and it would be a VERY good idea to have everything balanced and blueprinted while your in there. This can get very expensive, but less so if you do the install on your own.

The TEC-III I'm not sure if it is out yet, but I did read in one of Shiv's posts' that you CANNOT buy the TEC-II anymore.

The SDS-EFI setup would be nice, as it is quite a bit less expensive, though I have heard of some crank tooth mis-alignments with it. Not sure how much of a problem this would be on the install though.

Awesome! Looking forward to seeing the final draft up on the site!


Graham
 

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Yeah, I'm definately planning on pulling the block. Pistons and rods are budgeted for, and I think if I lower the compression ratio some I'll be able to run a lot more boost, and have a lot more fun without trashing the engine. And of course I have a 4EAT so I don't have to worry about that thing too much (although I will get a new clutch pack for it, along with a valve body rebuild and Torque Converter) so I should be good to go.

Now to find someone to balance and blueprint the engine. I can do the assembly myself, so that can save some $$$. :D
 

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Hey,

Any suggestions on good pistons and rods that will work on the RS?
 

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www.paeco.com

They can do anything you need. Forged pistons at pretty much any compression ratio, rods, etc. They can even build a complete engine for you.
 

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Me personally when I do build up my block, I will go through COBB. I have heard nightmares about pistons not being the right size once installed, and this is something I just don't want to have to go through.

COBB uses JE Pistons, though the design is their own, they are JE made, which automatically makes them an awesome product.

As far as rods, Carillo are nice, just make sure you get the right size.

Oh, and rods shouldn't really come into play for our cars until around 350-400 ft. lbs. of torque. But, if your gonna go in there, might as well save yourself some time and do the rods as well.

There is a good thread over in "the club" about rods right now.

Graham
 

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I called COBB - they don't sell pistons and rods seperately, and they want like $5k for a short block! Yeah, I'm sure it's awesome (whoop-dee-doo) but um, I'm not planning on abusing something that hard. I want a daily driver with some extra get-up-and-go.

Looks like I'll call Paeco and JE, maybe Crower for rods. Does ARP make rod bolts?

What do you recommend for rings?

Then copper head gaskets will be next.

What fun! Woohoo!
 

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the $5,000 cobb block you speak of is 22b based replica if i'm not mistaken. i also just posted in another forum about the 4eat. it is very sensitive to burn-outs because of it being linked to the AWD. the thing about that is that when you burn out your AWD system goes into convulsions because it can't figure out what to do and that stress will run into your tranny like a freight train.
 

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zoinkssooby said:
the $5,000 cobb block you speak of is 22b based replica if i'm not mistaken. i also just posted in another forum about the 4eat. it is very sensitive to burn-outs because of it being linked to the AWD. the thing about that is that when you burn out your AWD system goes into convulsions because it can't figure out what to do and that stress will run into your tranny like a freight train.
The 5k Cobb block is their stage 3 2.5L motor. Not the 2.2L block.
 

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About the head gaskets, just remember that it would seem better to have those blow rather than internals of an engine, as the combustive cycle is looking for the easiest way, and in high boost applications this is usually the head gaskets.

I also called COBB, though they told me they DO sell pistons and what not, for $700 a set (remember these are the JE's) with any compression ratio I want.


Graham
 

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Graham said:
I also called COBB, though they told me they DO sell pistons and what not, for $700 a set (remember these are the JE's) with any compression ratio I want.
Huh? I just talked to them yesterday and they said "No gots..." Are you sure? I must be talking to the wrong people!

Anyway, now I am having second thoughts. I may just go crazy on STS legal mods. I would never use the turbo except for street racing, and I like SCCA stuff so much, because then I can prove my skills against the clock and other similar cars.

Ah, what to do, what to do... :D
 

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James, I called them probably four months ago when I was contemplating doing my turbo project or doing an N/A engine build w/ new high compression pistons. They said they can get me any compression ratio piston that I want, and they are made by JE.

I myself am an avid autocrosser, though I haven't raced the car since the installation of the turbo (nearly two months!). When I do finally get back into it, I will be placed in the Race Class, with all the other engine swapped, turbo/supercharged cars. Sure it will be more difficicult, but you can always compare yourself to something like a WRX. Oh, and if you ever do a track day, this is somewhere that the turbo will make its largest impact. Autocrossing is fun, but someday I hope to move up a level and begin track racing.

I say go turbo, its so much fun to ACUALLY do it, especially if you do it yourself. I went into my project with NO prior turbo install experience, and came out feeling like a master of car performance. The whole thing was a learning experience, but more so it was challenge.

So, James, I DARE you to take the TURBO CHALLENGE!!!!!


Graham:D
 

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Graham said:
So, James, I DARE you to take the TURBO CHALLENGE!!!!!


Graham:D
Very tempting, but last time I blew all my money I got laid off. I am putting this into savings for now. When I get caught up, I will turbo my 2.5 and then we can have some FUN. :devil:
 

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The 5k Cobb block is their stage 3 2.5L motor. Not the 2.2L block.
i said 22b "based" as in it is modeled after the some design ideas they used(improved oil and coolant flow passages, fully closed and wire ringed cylinder deck)
also, check this site for tech documents http://www.ravensblade-impreza.com has tons of info and several pdf's of over-seas brochures in the download section including the 22b
 

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K, i just want to get something clear,
so if i was to install the stage two LudeSpeed turbo kit and ran only around 4-5 psi with everything stock except an aftermarket clutch and exhaust I should be OK for a lot of miles? How many miles?

What things do i need to watch out for when using the turbo on my 2.5 rs?
 

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One thing that you definetly need to be sure to have is some sort of timing control to prevent detonation in the engine. You can accomplish this by installing an Apex ITC (ignition timing controller) which allows you to retard the engine timing. Other options include a J&S Safegaurd, which utilizes a knock sensor in the engine bay and listens for detonation/pinging, which can be a cause for engine failure.

With an upgraded clutch and exhaust, timing control, and the Ludespeed kit @ 5 psi, you should be fine for many miles. The boost WILL cause extra ware on the engine internals, consequently reducing the life of the engine to maybe 80,000 miles instead of 100,000 (this is a guesstimate). You can blow your engine though. A good example would be hayscoob here on the board. He was running the Ludespeed Stage II @4.4 psi when his engine went, and he only had on for two weeks. He did NOT have timing control, and a possible catalyst for the destruction could be boost spike. You can search for his link and read more about it.

Once again, there is no guarantee that you engine will not let go, but if you do the install right, use the right electronics, and don't beat the car to death every day you should for the most part be golden.

Graham
 

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This is my first explosion on my MY00. Notice anything missing from the right side of the piston :)

Eric
 

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