First modification of my 2003 Mitsubishi Evolutionby Dan Hetorilla
Disclaimer
Why is this my first mod?
Believe me this buy was not planned at all. Sometimes I buy when I have the opportunity, time, and money. In this case I also had the sense that the HKS SSQV was going to be hard to find. So the credit card got hit with this purchase first. The first reasonable mod should be something like a boost guage or turbo timer. Actually those are other stories and I'm getting off-topic.
My intentions
I have bought this Blow-Off Valve (BOV) to improve turbo response time (keep it spooled when shifting) and improve the air seal when it's supposed to be closed. I've heard that the factory diverter valve leaks enough to degrade intake pressure. I expect very very little power increase, but expect a noticable turbo lag decrease.
The Purchase: Where and How
After doing some research on the web I decide to give a few shops around me a call. I live near Boston and Providence so I am able to hit a fair amount of places. But because of my impatience I only contacted a few. None had what I wanted so I went back to the Internet. The lowest price I was able to find was something like $205.00. I called them only to find out that they did not have any. So I kept going up the list; $206, $208, $210, etc. Until I came across Speed Alliance (http://www.speedalliance.com). The guy there said he'd have one drop-shipped to me for $226 plus shipping. Some references off the message boards said that BOV can use the 95-99 Mitsubishi Eclipse kits so I ordered that kit from him, HKS part number 1421-SM4US. I also was looking to vent back into the intake so I ordered the recirc kit for the Eclipse as well, HKS part number 1422-SM01US, at $40. The total with shipping was $280.80. I ordered this on April 7th 2003 over the phone by the way.
Anticipation
A couple of days had gone by and I didn't get the tracking number that the guy had said was going to be emailed to me. So I added the speedalliance screen name to my AOL buddy list and chatted with someone over IM that day. He said that the package was already shipped and on the way.
The box arrives! (sorta)
A week later, on the 5th day of the estimated 3-5 business days, the box gets an attempt of delivery at my doorstep. No one there to sign for it, argh! I wait one more day and have someone hang back.
The box arrives!Direct from the distributor, drop shipped like Speed Alliance said, the package is well made. It's quite obvious that the packaging was made from a bigger box that probably contained many many HKS products. Nevertheless it was well taped and undamaged. Kudos to the distributor and, for once, UPS in handling the package.
Opening the boxUpon inspection of the inner packing, I found that the package was fairly packed. Not tight but not in a way that the inner contents were not moving all over the place. They used a baggie with shredded paper to top off the space. For once I'm not handling contents with packing peanuts sticking to everything, a plus.
Inventory takenThe BOV had it's own box and the recirc kit was just a thick bag with the proper stuff in it. The BOV itself was a another box within its own box, but that inner box was a little on the big side so the BOV, albiet wrapped in foam wrap, was rolling around a bit in it's own semi-loose space. The 'retail' box was topped off with a baggie of peanuts. Yay! no handling peanuts directly in this shipment. Upon unpacking I noticed that I got a bonus recirc fitting in the BOV box. Looks as though I wasted $40 on the recirc kit since I probably won't need the hose and clamps.
BOV unwrapped and measuredCareful inspection of the outside of the BOV showed no scratches or dings. It weighs about 505 grams, which is a little over 1 pound. It's a little under 5.5 inches long and the largest diameter is a tad under 3 inches.
BOV inlet measuredThe inlet is a flat bell designed to accept whatever fitting is need to adapt to your application. Since I bought the Mitsubishi Eclipse kit it came with a metal fitting that accepts the hose coming off the engine intake. I noted a flat spot, probably to allow the lock ring to fit over.
BOV front and back viewsThe front view of the BOV looks good. Note the purple piece inside. This is the smaller relief valve that starts the blow-off. This is the start of the "sequence" and part of what makes this BOV perform better than others. The side profile is pretty much like the top profile as shown above. It's an attractive bullet shape and definitely made to be shown under the hood. All nuts and bolts are readily accessible by normal allen and flat wrenches.
Installing the recirulation fittingThere are eight allen bolts that hold the outer/front housing on the main body. Four of them tighten the housing itself onto the main BOV piece. The other four go through the housing and hold the gasket on. I used a 2mm allen wrench.
Removing the insertThe insert pops easily out of the housing once the gasket is removed. Note the tabs on the insert, there are two and they are different sizes so you can't install a piece wrong. For those that will use this BOV to Vent to Atmosphere (no recirc) you can buy two other fittings that tailor the blow-off sound to your liking.
Putting the recirc fitting inIt fits just like it's supposed to. No tabs on the recirc fitting though. I noticed the inside of the housing is a little rough but not dangerous... no burrs or gross irregularities.
Reassembling the BOV housingWhen I put the gasket back in I noticed a hard side and a soft side, so I put the soft side towards where relief valve end. I was very carful to tighten the screws down like you would an exhaust header gasket: A little at a time, equally around the whole housing. Probably not needed but my mechanic friend will confirm that I tend to be slow doing these sort of things, hee hee. I kept in mind that this BOV will need to handle up to 22psi nominal, so I tightened it down good, but was careful not to tighten beyond the miniture bolts' integrity.
Putting the O-Ring into the fitting
This O-Ring is very important of keeping the pressure in. Notice the oversize channel giving space on the inside of the O-Ring. This lets the air pressure get beside the O-Ring and push it out, collapsing it a bit and further making a better seal. The only other seals are the pull lever diaphram and the relief valves themselves.
Introducing the lock ringThis is what will lock the air inlet fitting onto the BOV. I quick put one end in to make sure that's where it goes.
Checking out how the fitting will go onI slip the lock ring over the BOV inlet bell and match up the inlet fitting. Looks like a sound fit, no protrusions or blockage.
Wrestling the fitting on!
So I went out and bought a lock ring compression tool. The two holes on the end recieve the tool and you squeeze it to make the diameter of the lock ring smaller. I totally missed taking pics of this process because: 1) I bought the tool too small and 2) I shouldn't have put the housing back on. installing the lock ring is MUCH easier with the housing off. Make doubly sure that the O-Ring doesn't get bound up during the lock ring install, since binding will break the O-Ring and there'll be leakage there.
Assembly complete, taking inlet/outlet measurementsThe Inlet is about 1.375 or 1-3/8 inches. The outlet is about 1 inch. I had previously looked at the factory diverter valve and noticed that it was pretty much a 90 degree angle. So I made sure the inlet fitting was as close to that as possible. With the inlet pointed down and the outlet pointed towards you, the fitting should point off to the left. You may notice how important this is later.
Locating the factory diverter valveFrom the front of the car, look on the head cover to the right and you'll notice a thin hose, it's a typical vaccuum hose which will lead you straight to the diverter valve under the top radiator hose. This picture is a view of it looking from the passenger side of the car. Note the red on the left side of the picture, that's the front side of the head cover. Also note the exhaust heat shield. Be very careful if you're within one hour of the car's engine running. Those parts might still be very very hot! Let it cool, you'll need the space and it's safer.
It's not buried, trust me!There are other parts of the car that will be more buried than this, so if you think this is buried then you might consider factoring in payment to a professional for other mods. This one is easy easy easy. We only have three clamps to loosen to get this off. The first obvious hose clamp screw is easily accessible right from the top. Use a phillips head screwdriver or a 10mm nut driver to loosen.
Let's make some spaceAfter removing the other end of the vaccuum hose, I decided to make more room to work in, so I popped the airbox cover off and moved it aside. To do this the two front plastic fasteners come out easily if you ever so slighty press on the middle of them and snap them in (down) about an eighth of an inch. If you press too hard you can push those pices all of the way through and it'll fall into the front area void. Keep your thumbs over them as you lift the airbox cover off so you don't lose them. Be careful not to lean on the air filter and break it.
Got space, now we're rollinNow it's very easy to get the inlet hose off with the airbox inlet out of the way. Also the clamp for the hose that connects to the outlet end of the diverter valve is more accessible. I used a small 1/8" drive ratchet with a 10mm socket to loosen the hose clamp. The diverter valve pops right out then I removed the vaccuum hose from the diverter valve.
Comparo, Factory vs. AftermarketOOPS! In this picture the valves are not positioned similarly. The top of the HKS is pointing down and the top of the factory diverter valve is pointing to the left. Anyhow note that the HKS is almost double the size! I can't imagine buying the race version and being able to fit it in the factory location. I heard that the GReddy BOV is almost the exact size as the factory one, with no extras to buy. Also note that the outlet of the factory valve (pointing to the right) is bigger than the HKS (pointing toward the top). hmmmm, had to think about that one. Luckily I thought of the solution, it's next.
Outlet size difference, solved!Well it looks like that $40 freakin waste of money paid off a teeny bit. The hose that came with the recirc kit had an outside diameter perfectly the same as the diameter of the outlet fitting of the factory diverter valve. So I cut a piece off and used it as a gasket to make the outlet of the HKS SSQV big enough to fit into the intake feed. So look for a scrap piece of hose that has a 1 inch inside diameter and a 1.375 or 1-3/8 inch outside diameter.
So yeah, it's nice to have connections to a professional garageThe control tube on the HKS is smaller than the factory vaccuum hose. HKS thought of this by including an adapter. Oddly, they didn't give me the smaller hose that I need. It wasn't on the part checklist either, so it's not supposed to come with it!? So I grabbed a short length of 6mm fuel line to go from the adapter to the HKS BOV. It's such a tight fit that no clamps where necessary at all.
Twist, shove, that went in easy!It popped in so fast that I didn't pause to take pictures of each fitting going in. Note that the top end is pointing up for easy adjustment of the relief valve spring inside it. The excess hose because of the adapter is flapping about so we'll have to do something about that. With the head blocking one side and the radiator hose blocking the other side it's gonna be too hard to change the diaphram when/if I need to... luckily it's easy enough to pop this right back out.
Thinking ahead is good sometimesHere's the proof that having the inlet fitting pointed in the correct direction made things easier. If it was pointed the other way we would surely have a kink in the inlet hose. I'm especially happy that the radiator hose has an extra covering here since the new BOV actually rubs against it (not severely).
Tools used to install the BOVFrom top left to bottom right:
Tidying upI zip tied the BOV control hose to the radiator hose. Now it's not going to flap around. INSTALL DONE!!! Beer me.
Initial adjustmentI always wait until I get some coolant temp before I spool up the turbo. Note the mileage. I've driven 1179 of those miles and it looks like I'm headed for another 20MPG tank of 94 octane gas. First thing I do is drive down the street. With all windows open I still couldn't hear the BOV pop. So, parked, I take off the airbox cover (and proceed to LOSE one of my plastic fasteners because I did not lift the cover with my thumbs over them! blah!) and lift out the filter. I rev the engine a bit and notice the pop-off now. ok it's working. Now for the mystery of adjustment...
Reviewing is GOODWhile going through the pictures I made I noticed that maybe I tightened the zip ties too much and will possibly cut off the control flow for the BOV, sheesh! So I cut the zip tie off.
Still looseThis is what I don't want happening, if for some reason it flops up like this there's a chance that the control flow will get cut off due to the pinch of the tub on the right. Not sure what to do now.
Cheese fix for nowOk I'll use two loose zip ties to hold it from going all of the way back. I'm going to find some scrap conduit small enough to shove under the foam cover so I can zip tie that tube back in the radiator hose.
How does it run?
When cruising I notice even the slightest lift off the gas pedal makes the BOV pop and the car acts like it's running rich... I think. I really need to get a boost guage very very soon. Right now the adjustment seems to affect at what speed I experience this. A loose setting makes it happen at lower speeds, a strong setting makes it happen at higher speeds. Like I said a boost guage purchase is in the works NOW.
Update: Now that the gauges are installed, it basically gave me a better idea of how and when it releases. I've experimented with the adjustments to both extremes. Here's what I found:
The little valve releases on throttle lift no matter how tight you have it. With the HKS SSQV the adjustment
seems to be more for the big valve to pop open. Now that I run without an airbox (ran across a cone filter during
my travels) it's loud even though I have it recircing. I'm still working on getting more sound clips.
SOUND CLIPS!
Please note that although I am recirculating the blow off I have removed the airbox and replaced it with a cone
filter, the blow-off sound is very audible once you do this. No need to vent-to-air to get your cool blow-off
sound!In all of the sound clips below the microphone was placed in the engine bay, clipped to the battery sheath. The microphone cord was temporarily routed through the inner gap between the front fender and the firewall, passing right on top of the door seal into the car, where the recording equipment was operated from.
-Preview- Quality Sound Clip
At about 5 seconds you will hear the small valve flutter, this was light acceleration from a stop into 2nd gear. At 10 seconds you will hear acceleration and gear shifts to 3rd then 4th. This recording was made with a voice recorder using the cheap wired microphone that came with it. The sound was then recorded by the Microsoft (R) Sound Recorder version 5.0 on my Windows 2000 workstation. The voice recorder was hooked into my X-Gamer sound card and the recording quality was set at 16-bit sample size, 48,000hz frequency range, monoaural recording (94KB/s). The sound clip is 15 seconds long. The file size is 2,813KB. Click this link to listen
The following sounds were recorded by the Microsoft (R) Sound Recorder on my Windows 98 laptop. I used my clip-on studio microphone normally used on my trumpet, hooked into my Behringer Eurorack MXB1002 portable mixing board. From the mixing board an RCA to 1/8" adpter was used to connect directly into the mic input of the laptop, which has a built-in Maestro sound card.
Sound Clip #1 - Hard Acceleration
This is a launch, pure and simple. You will notice I actually got some tire spin in first (road bumps)... then shifting gears so fast because I was running out of tach! I also very very quickly ran out of road! So no shift into 5th. The recording quality in the Microsoft (R) Sound Recorder was set at 16-bit sample size, 48,000hz frequency range, monoaural recording (94KB/s). The sound clip is 25 seconds long. The file size is 2,347KB. Click this link to listen
Sound Clip #2 - Light Acceleration
This is normal acceleration. This was to demonstrate the little valve popping even on slight lifts such as casually shifting gears. The recording quality in the Microsoft (R) Sound Recorder was mistakenly left at 8-bit sample size, 22,050hz frequency range, monoaural recording (22KB/s). The sound clip is 19 seconds long. The file size is 418KB. Click this link to listen
Sound Clip #3 - Playing with 2nd gear
I wanted to try an demonstrate how quickly the turbo spools in this one, started recording in 2nd gear at around 3000RPM then jabbed and let off the gas a few times. Notice that the turbo spools immediately. It was too hard staying in second so at the end of this clip I went into 3rd then 4th. Again the recording quality in the Microsoft (R) Sound Recorder was mistakenly left at 8-bit sample size, 22,050hz frequency range, monoaural recording (22KB/s). The sound clip is 12 seconds long. The file size is 276KB. Click this link to listen
Sound Clip #4 - Light Acceleration, better recording quality
After the 3rd clip I noticed the recording quality needed to be set for each recording or it'll default to the lesser one. So I went back and did light acceleration again. The recording quality in the Microsoft (R) Sound Recorder was was set at 16-bit sample size, 48,000hz frequency range, monoaural recording (94KB/s). The sound clip is 15 seconds long. The file size is 1,469KB. Click this link to listen
Sound Clip #5 - Playing with 2nd gear, better recording quality
Same deal as clip #3, but this time I had the recorder set up like I wanted to. The recording quality in the Microsoft (R) Sound Recorder was was set at 16-bit sample size, 48,000hz frequency range, monoaural recording (94KB/s). The sound clip is 18 seconds long. The file size is 1,748KB. Click this link to listen
Disclaimer and Notices
These pictures were taken with a consumer point and shoot camera (Nikon Coolpix 950) without tripods and professional photo lighting. Some of the images may have been blurred from me pressing the shutter button. Also I am not a journalist. My profession is in computers and project mangement, and I have a heavy background in Technical support and customer service. My commentary may be simplistic at times but should not be construed as condescending. My intention is to attract an audience that can digest this information and use it to their advantage when upgrading their own cars. I am not a professional mechanic but I have worked with one. I also belong to an SCCA Club Racing championship race team, so performance is not foreign to me. What I learn is mostly from the race track. I hope this helps you. I welcome comments, corrections, and suggestions. Please post them at http://forums.evolutionm.net/showthread.php?s=&threadid=20612. Thank you for your visit. Return to the top