Jump to content
Ultimate Subaru Message Board
Subarubiflu

Turbo alternitive to an ER27

Recommended Posts

I'm looking for a way to put more fun into my Xt6's I want to turbo charge but I was told You need a lot of turbo for 2.7ltrs and the sohc heads don't flow well to accept a turbo. So I would be better off with some sort of Dohc already turbo engine. I don't have the money for a wrx engine. So I was trying to figure out what other turbo engines whould be a good canidate for swapping, that would also have the support of the aftermarket, and take mods well?

Share this post


Link to post
Share on other sites

I don't know how the price would compare, but the EJ22T out of turbo legacies is a great engine that would meet all of your requirements. I would imagine you could find a wrecked turbo legacy for a reasonable price.

Share this post


Link to post
Share on other sites
I'm looking for a way to put more fun into my Xt6's I want to turbo charge but I was told You need a lot of turbo for 2.7ltrs and the sohc heads don't flow well to accept a turbo. So I would be better off with some sort of Dohc already turbo engine. I don't have the money for a wrx engine. So I was trying to figure out what other turbo engines whould be a good canidate for swapping, that would also have the support of the aftermarket, and take mods well?

 

You can gain up to 20hp if you modify your intake, exhaust and advance your ignition.

Share this post


Link to post
Share on other sites

depends how much power you're after. the Xt6 isn't a good candidate for a turbo, but the easiest and cheapest way would be to install a turbo on your XT6 and run it at low boost.....5-7 psi is probably the most you can get without needing any kind of controller or reach the limit of the fuel system. combined with a high end tune up, light weight crank pulley and intake/exhaust mods like kevin mentioned and you'll be adding good power. but you are limited by the computer and fuel system, that's why i say 5-7 psi max. but the good thing is that it would only cost you a turbo, exhaust and intake work and a good tune up which you would want no matter what engine you're getting. there is no after market exhaust/intake for the XT6, but installing any other motor is going to require custom work anyway so that's a wash. if you're doing the intake/exhaust work yourself then you'd basically only need the turbo and associated parts (BOV...etc).

 

a 2.2 turbo or other alternative is the way to go if you want lots more power and a real screamer. but that's expensive, requires installation (more $) and custom work as it won't work with the stock ECU, so you'll need the 2.2 computer and wiring harness as well. and if you have an auto trans i don't know how the wiring harness will swap over as the auto trans uses input from the 2.7 liter sensors...TPS at least. it's definitely possible, definitely a good option, probably a light motor but sounds like it doesn't have the cost advantage you're looking for.

Share this post


Link to post
Share on other sites

2 nitpicks. First, a lighter crank pulley, or even a lightened flywheel, will not increase your power. It will allow the engine to speed up and slow down quicker; and the pulley won't even really do that (insignificant polar moment of inertia). I would suggest you take the money and spend it on something else like a custom exhaust or quality ignition components.

 

Second, also sort of a weight thing, is that the EJ22 is not a light engine. I have not had the pleasure of lifting or otherwise dealing with an ER27, but I would suspect that the EJ22 (sans turbos) would weigh about the same as an ER27.

Share this post


Link to post
Share on other sites
2 nitpicks. First, a lighter crank pulley, or even a lightened flywheel, will not increase your power. It will allow the engine to speed up and slow down quicker; and the pulley won't even really do that (insignificant polar moment of inertia). I would suggest you take the money and spend it on something else like a custom exhaust or quality ignition components.

 

A lightweight pulley will allow more power to turn the wheels instead of turning the crank pulley. Having more power available to accelerate the wheels rather than the crank pulley is useful.

 

The 2nd advantage to having a lightweight crank pulley is that it eliminates the rubber bushing thingamajigga that fails on the stock crank pulleys on a lot of the XT6s. I haven't experienced a failure of an XT6 crank pulley since I luckily got an aftermarket crank pulley from two different companies but I have read about it from posts from other XT6 owners. $$$ spent on having more power available to the wheels and added reliability is a double plus.

 

Here is a thread I started on an aftermarket crank pulley and the difference between the stock and aftermarket one.

http://xt6.net/forum/viewtopic.php?t=2958&postdays=0&postorder=asc&start=0

 

Here are some pics of the weight difference between the two.

 

mini-pulleys-rear.jpg

 

 

Stock XT6 crank pulley weight:

mini-stockpulleywght.jpg

 

 

ProECM XT6 Pulley weight:

mini-proecmpulleywght.jpg

 

 

Sorry for getting off the turbo XT6 topic. I am with you on this one though. I've been wanting to turbo my XT6 for years. I'm awaiting Gary or someone else to complete it first. I get passionate about it for a few weeks, then it dies down and comes back again. Good luck!

Share this post


Link to post
Share on other sites
A lightweight pulley will allow more power to turn the wheels instead of turning the crank pulley. Having more power available to accelerate the wheels rather than the crank pulley is useful.

 

The 2nd advantage to having a lightweight crank pulley is that it eliminates the rubber bushing thingamajigga that fails on the stock crank pulleys on a lot of the XT6s. I haven't experienced a failure of an XT6 crank pulley since I luckily got an aftermarket crank pulley from two different companies but I have read about it from posts from other XT6 owners. $$$ spent on having more power available to the wheels and added reliability is a double plus.

Lighter rotating components do not change power. They change how much is stored and released. A dynomometer may show a difference, but it is because of the dyno's method of measuring power, not the physical reality of the power. The diameter and weight distribution of a crank pulley is such that its contribution to the rotating mass' polar moment of inertia is negligible.

 

HOWEVER, the issue of the stock pulley coming apart would definitely be a valid reason to go to almost anything else.

 

As far as turbo'd ER27s... I have been pipedreaming about one with stock compression and a pair of turbos off of EA82Ts. Good low end torque, good off-boost economy, and the ability to keep the effective VE from sagging with increasing RPMs. Ummmm... power...

Share this post


Link to post
Share on other sites

Thanks for the help. I think keeping my xt6 an xt6 is probably the best way to go. I just figured 4 is lighter than 6. besides I already have 4 ER27's laying around I should probably do something with. I just enrolled in a CC class called "high performance engine building" so hopefully I can see good things from it.

Share this post


Link to post
Share on other sites

I'm getting ready to Turbo my 6.... hopefully BEFORE The Dragon run next year so I can show off all my bling. My current plan is the low pressure one... My goal is about 200 horse, which I think is attainable with all the mods I have to current. My major use of compontents comes freshly stolen off of a Turbo Legacy... chop off the old flanges on the exhaust and weld on new XT-6 ones... the turbo and all and I'm either going to add a 5th injector or MegaSquirt it. The Megasquirt is over there int eh corner---> mostly cuz I fear it I dont want to readily use it. I also plan a nice AWIC with a small tank and Front Mounted Heater Core(FMHC) to keep things cool, but my list of parts to get is still fairly long. I have the header and turbo... now just the down pipe, gauge collection, BOV , intercooler and I'll be ready. Ohh....

My second point. Never been to a dyno with my car BUTT.... I have installed that lightweight pulley shown as I was on my like 4th pulley failing..... I notice a difference in its ability to rev faster... mostly in the corners when I gun it, its responce is MUCH better... Well worth the $160-$180 I spent on it for sure... plus its cool.:brow: Ohh and if anyone needs an EJ22T... I have one... magically for sale... :drunk:

Share this post


Link to post
Share on other sites

Second, also sort of a weight thing, is that the EJ22 is not a light engine. I have not had the pleasure of lifting or otherwise dealing with an ER27, but I would suspect that the EJ22 (sans turbos) would weigh about the same as an ER27.

 

the er27 is a heavy beast. it weighs alot more than an ej. im guessing 75 lbs more

im sure somebodys got numbers.

 

exhaust and intake make a huge difference by themselves. stick a 2.5 inch exhuast behind the y pipe(after you gut the cat) and put a big cone filter on, crank the timing, and you will like it alot more.

 

theres alot of metal you can take out of the heads, and intake, that make a good difference too. take the heads off, flow them, and deck em, so you can get up to 10:1...

 

 

on the turbo stuff. these cars have a maf sensor, so it should be good with boost with out any other fuel changes. the na mpfi motors take well to boost, so the 6s should be the same

Share this post


Link to post
Share on other sites
A dynomometer may show a difference, but it is because of the dyno's method of measuring power, not the physical reality of the power.

 

So if you change to a lighter weight pulley on a dyno and measure more power after the change, it is not a physical reality that you have more hp to use? You mean, even if this difference it measureable on the dragstrip as well, you do not have more power available to use? Note: I didn't say more horsepower but more power that is available to use (to accelerate the car).

Share this post


Link to post
Share on other sites
So if you change to a lighter weight pulley on a dyno and measure more power after the change, it is not a physical reality that you have more hp to use? You mean, even if this difference it measureable on the dragstrip as well, you do not have more power available to use? Note: I didn't say more horsepower but more power that is available to use (to accelerate the car).

A symantics discussion may develop...

 

"Power" is a specific term, meaning unit torque (force times distance) applied over unit time. Standard units of power are watts and horsepower. Your engine does not suddenly produce more HP/KW because of less rotating mass. If that were true, then removing your flywheel would about double the engines HP/KW.

 

Rate of acceleration is mostly determined by torque. With a lighter flywheel/pulley, less of the developed torque is used to overcome the PMI of the rotating mass, so you can get greater effective torque, so, yes, your engine will rev faster and you can accelerate faster. Dynos can be spoofed by this because, theoretically, HP should be measured at a steady RPM; Dyno operators are more likely to just sweep through the rev range and find what pops out.

 

The pulley is such a minor part of the rotating mass, and an insignificant part of the accelerated mass of the vehicle, that singling it out as a place to spend lots of money just to lighten it is not called for in my opinion. Replace it with a solid, more reliable part that happens to be lighter? Sure.

 

Anyways, will an engine with less rotating mass rev quicker? Yes. Does it produce more HP/KW? No. Can it seem like it is producing more HP/KW? Yes. Will it produce faster 1/4 mile times? Maybe.

 

Like I said, mostly symantics. :)

Share this post


Link to post
Share on other sites

I'm dumb, so I'm gonna try and dumb it down. So what you are saying is that the engine is not making anymore physical power aka, the horsepower when measured at the crank is still the same. BUT the "driveline" has been made more efficent so the horse power measured at the wheels is greater. Right?

Share this post


Link to post
Share on other sites

i don't know much about motors so my statement about increasing horsepower was wrong. but i think it does help somewhere in performance and that's what i was getting at. if you made a 238 pound crank pulley i think that would slow the car down. i don't know where you reach the point of diminishing returns for a car motor but it seems possible that a lighter crank pulley could help things out a bit.

Share this post


Link to post
Share on other sites
I'm dumb, so I'm gonna try and dumb it down.... BUT the "driveline" has been made more efficent so the horse power measured at the wheels is greater. Right?

No, the driveline isn't more efficient, it is just "compromised" to a different set of preferences/desires/goals. Significantly reducing the rotating inertia will make the engine feel rougher, will be harder to drive in day-to-day traffic, and in general just feel more highly "strung".

 

i don't know much about motors so my statement about increasing horsepower was wrong. but i think it does help somewhere in performance and that's what i was getting at. if you made a 238 pound crank pulley i think that would slow the car down. i don't know where you reach the point of diminishing returns for a car motor but it seems possible that a lighter crank pulley could help things out a bit.

Yes, less rotating mass allows the engine to change RPM more rapidly. A 235 pound crank pulley would slow down the engine's (and car's) acceleration, but will not effect the car's top speed. ("fast"... semantics (sorry for the previous sp)) And the weight is not so important as the effective distance of the weight (mass, really) from the center of rotation: A 238 pound lump of extremely dense material 1 inch in diameter has nearly zero effect on the engine's ability to change speed, whereas 5 lbs at 10 ft distance would have a tremendous effect.

 

A pulley that is several pounds lighter at an average or 2 inches from rotational centerline is not significant.

 

I feel bad that we have kind of hijacked this thread. :-\

Share this post


Link to post
Share on other sites

So is it basicly the same as using a lighter flyweel? My cousin swaped both flyweel and pullys, and his car seems to rev faster and it did improve his HP acording to a G-tec HP meter. I was impressed. However It did seem to want to either launch or die, So maybe that could be considerd to be "high strung" I did not notice a rough ride though. He seemed to adapt to the new touchy clutch but he a much better driver than I.

Share this post


Link to post
Share on other sites

Baisically, if you want less rotational inertia, lighten your flywheel. The pulley is so light and of such small diameter that it may as well not be there at all when it comes to rotational inertia.

 

Anyway, on the turbo 6, someone has to do it, may as well be you!! :brow:

Share this post


Link to post
Share on other sites
Baisically, if you want less rotational inertia, lighten your flywheel. The pulley is so light and of such small diameter that it may as well not be there at all when it comes to rotational inertia.

 

Anyway, on the turbo 6, someone has to do it, may as well be you!! :brow:

 

Why not me? :banghead: I want a turbo 6. me, Me, Me, ME, ME!!!

 

I posted this quote at the XT6.net site. Do you peeps think the math holds true?

 

"Speaking of possibilities (bringing back an old post), there is a dyno put up today by a guy named Will at USMB. He dyno'd an EA82T with an intake, TWE header/downpipe, boost controller and intercooler. Here is his result: http://consumer.inkfrog.com/pix/WJM/rx_all_runs.jpg

 

At 14psi he got 142.08hp and 182.20lb-ft of torque.

 

At 15psi he got 161.68hp and 205.63lbs-ft of torque.

 

This is with an assumed drivetrain loss of 30%. If this is the case, then at 15psi he's making approximately 230hp and 293lb-ft of torque at the crank. Not bad at all.

Fast forward to us turbocharing our XT6s with the same stock compression ratio as the EA82T engine (7.7:1). Take (230hp/4)*6 and (293lb-ft/4) * 6. See what I'm getting at?

 

 

345hp and 440lb-ft of torque at the crank.

 

Just something for us to ponder over and dream about."

Share this post


Link to post
Share on other sites

Another thing to think about, and doesn't seem to get discussed much, is that the normal route to horsepower is through increased RPM. Spin the engine faster, keep the effective VE from falling off (through normal intake/valve/exhaust tweaks, forced induction, or both) and your HP will increase. My question with the ER27 is: Does it have any crank torsional vibration and/or oil feed issues if it is spun significantly faster than usual?

 

(As an example of what I mean... When the Datsun 240Z first got raced, it suffered from crank failures. It was a long crank that would fracture from torsional vibration stresses when engine speed increased into its natural harmonic frequency. People also would cross drill the crank for increased oiling, and when spun faster the crank emptied all of its oil before they reached the more distant mains and rods.)

Share this post


Link to post
Share on other sites
Another thing to think about, and doesn't seem to get discussed much, is that the normal route to horsepower is through increased RPM. Spin the engine faster, keep the effective VE from falling off (through normal intake/valve/exhaust tweaks, forced induction, or both) and your HP will increase. My question with the ER27 is: Does it have any crank torsional vibration and/or oil feed issues if it is spun significantly faster than usual?

 

(As an example of what I mean... When the Datsun 240Z first got raced, it suffered from crank failures. It was a long crank that would fracture from torsional vibration stresses when engine speed increased into its natural harmonic frequency. People also would cross drill the crank for increased oiling, and when spun faster the crank emptied all of its oil before they reached the more distant mains and rods.)

 

Hmmm....that's interesting. I had never really thought about that. I don't have any ER27s around to do some field testing on, but I could fire up the EA71 I've got, crank it up until the valves start floating, and see how long it lasts:drunk: .

Share this post


Link to post
Share on other sites

Hmm, well, seeing as the ea81 is reputed to be able to hold 10,000rpm indefinitely, you'd think that the er27 (im assuming the crank is of similar design, just with an extra bit) would hold at least 8,000rpm. Utter speculation though.

How many main bearings does the er27 have?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×