Riva Sponsons Kit 250X $389.95

 Newest part for the 250X is the Riva Sponsons.

The new sponsons allow for 12 different locations of mounting them. This gives me 12 ways to tune my boats handling to my own liking. Nice because in the past I have had only 6 with older Beach House sponsons.

The backing is shorter and not as thick as the stock units.

Also I noticed the stock sponsons have a step in as the Riva ones do not. Look closely at the stock sponsons at the downward angle the rear has. I’m confused about the stock sponsons, first it seems that the front part offers nose lifting ability but the rear of it seems to aid in pushing down the nose. Well I don’t know enough about this to even worry so off in the attic they go and on with the Riva ones.

Here are the back side to them.

Assembly is so simple. Could do a write-up by why, when the instructions are so simple. I opted to use Red Loc-Tite on the backing plate bolts but this is because I plan on keeping them in place for a long time. Ive heard that using red could lock the bolt into the hull inserts and causing them to turn along with the bolt when trying to remove them later. I also opted to use no thread locker on the paddle bolts until I have tested all positions. Once I find the sweet spot then I will use Loc-Tite to ensure the bolts don’t back out of the paddle.

Finished. Now all you need to figure out on your own is how you want to set them for your style of ridding. As I ride more then Ill update this posting.

Practice Race at St. Pete Beach…. 

WOW these things will make this monster rail. Taking turns are now vary much a serious business. Putting mine down I was able to turn in wash and smooth conditions. Vary impressive. As the photo shows in surf condition the boat turn well and even caught me off guard. Boat turned but I did not follow with it. My lazy days of riding have just been given notice. Time to get serious, the sponsons have now given the handling a competitive edge for racing Closed Coarse.

After taking this salt water bath, I decided to try more settings. Moving them up and down, forward and back, all showed different effects that to me was not what I was looking for. Seemed to turn tighter the further back I went. Down positions digged harder making for fast unexpected turning and slowed down the boat. Up and forward started making the boat ride as if stock.Talking with Riva as to how they set theirs and found a great setting.

 

A = 1.25 inch aprox.

B = o.5 inch aprox.

C = 5.25 inch aprox.

This setting to me was by far the best. I noticed no speed loss and major improvements in turning with out excessive digging or gripping. Gripping in my explanation is turning smooth then have a hard unexpected whip around effect. Its this gripping that always throws me. Still it will be completely up to you as to were you like your sponsons set. Adjusting may take several different outing to get them to your own liking.

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R&D Powershot $461.92

This new item for the 250X has been used on other watercraft models in the past. Now for the 250X it comes pre-programmed from R&D. This item has been tested for optimal performance and proper A.F.R. This unit is a plug-n-play addition to your motor.

Easy to install. The only hard part is getting the plug off the injectors.

I took my spark plug wires off to gain better access to the injector plugs.

R&D says its best to use a 90 degree pair of needle nose pliers. I used my hands and now understand the idea behind those pliers.

Using the supplied zip ties I secured the wire bundle so as no rubbing or interference to the motor.

Using the supplied Velcro I secure the programmer to a safe flat service. Easy to get to but defiantly in a dry spot.

Even though the Controller is programmed from R&D they have allowed it to be further altered for those running additional modification that may require a bit more fuel. Here is the default 250X Controller settings.

Powershot-Instructions

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UMI Steering $682.00

Used on 250X and LX models.

This Modification Should NOT void your Warranty.

Lets get this thing started. I’ll do my best since no instructions were included in the kit.

The good news is that no hull drilling or relocation of the steering cable is required.

Start with taking off the steering pad cover (39067). Four cross head screws hold the black cover on (92009). Once this is complete you will see that there are rubber tabs need to be pulled free of screw posts. Now take the red buzzer out of the white pad and remove pad (39156). Now remove the throttle trigger (39074) and engine switch/tether(13151) putting any loose parts in a safe place.

Remove the steering neck from steering column. Remove rubber shield from four plastic tabs (39087A). This allows it to fall loose to expose the four bolts (92002A) holding the column to the steering shaft. Using a long extension socket to reach down between the rubber shield and steering column remove those four bolts. Careful to not allow any bolts to drop down into the engine compartment.

We can now move onto the Sides (14091B/O) and Center(14091D) cover. The side cover that has the gas cap can be completely removed easily. I did this by removing the gas cap from the safety chain and then removing the three bolts  holding it onto the hull and center cover. Place nuts and bolts in a safe place. Carefully lift up and forward to allow filler neck to pull threw the rubber neck guide. Be sure to replace the gas cap to avoid  a large amount of fumes from leaking out of the tank. Open the glove box completely and pull up gently to remove glove box door to place in a safe place.

Continue onto the side cover with the flush kit spicket. Remove the three bolts that secure it to hull and center cover. Lift gently to remove the securing tabs from the slotted section of the center cover. Allow the side cover to gently hang to the side so you can reach the nuts holding the center cover down. Remove them, three on each side, placing them in a safe place. Be sure to remove the reverse cable from the reverse lever using the small side access on the center cover. Gently lift center cover just enough to allow the flush kit hose out from under the center cover. Now you may move the side cover that is attached to the flush hose down the foot tray and out of the way. I used a soft clean towel to protect the cover from scratching. Remove the two face bolts on instrument face and two from behind the instrument cluster to free it from the center cover. Now you want to find the bypass outlet hose attached to the center cover. Disconnect it from the rubber nipple. Now you may lift and rotate the center cover to the side, carefully of the immobilizer wire still attached to the glove box.  Again use a towel to protect from scratches.

Should look like this now.

 

Find the metal ring holding the rubber wire plug into the steering base. Remove the two bolts holding it down and pull gently up on wire to free the plug to be removed from wiring. Lift off steering cable cover door. Reach inside and remove the steering cable from pivot pin.

Now remove the four bolts holding the steering base to hull. Slowly and gently lift out steering base Assembly. Careful to not tear or damage the gasket. At this point you will need to unplug all wire harnesses and disconnect the throttle cable from throttle lever.

Now that you have the base plate free from the hull, carefully remove the base gasket and save this for install of the UMI system.

You will need to also save the throttle cable nipple (A) and the sensor magnet.(B)

You can retrieve the magnet by either taking the stock steering base apart or us a small pair of needle nose channel locks. I ended up taking my stack column apart to retrieve the magnet. 

 

When assembling the UMI the throttle cable nipple will need to be the second one in from the last hole. If you put it in the last hole then the cable will bottom out when turning left. USE RED LOC-TITE on this part. You don’t want that nipple coming loose. Install the magnet using the stock screw with Blue LOC-TITE.

 Assembling the UMI is easy. Use the stud mounts for the pick up sensor. Be sure to use Blew LOC-TITE and everything else you assemble.

Remove pick up from stock steering. Save the screws and mount it on the UMI. Be sure to flip the cable with zip tie to other side to avoid hitting the billet support ridge.

Now completely assemble steering and ensure lever arm is lined up properly with pick up sensor.

Install the gasket you kept earlier and assemble the UMI onto the hull. Be sure to reconnect all plug after pulling through the UMI plate cable hole. Reaching in through the glove box hole, I reconnected the steering cable to the lever arm. Ensure you have ran the dash plugs, start/stop plug and throttle cable through the plate before bolting it down to the hull. Use RED LOC-TITE on these four bolts. Be sure to put in the cable holder in upper right side of plate.

At this point you will now need to put back together the dash, center cover and side covers. Once you have completed that you can then put on your bars.

After market bars will require you to drill a small hole so the stock start/stop bottom can fit flush. I chose to install my set back-wards in hopes to avoid an accidental bump of the stop button during competition.

I used the UMI billet finger throttle but some use the stock one with no issues. Installing the UMI Finger Throttle was easy and uses a adapter piece to adapt to the stock steering cable.  

 

I then went to adjust my throttle cable at the throttle body and at the adapter. Ensure you resting point on the finger throttle is not to loose but not tight. If it is not adjusted correctly then you can damage the cable.

Be sure to slide rubber cover over finger throttle adjust so as to protected it.

Now zip tie down loose cables and wires so they don’t rub. This rubbing can cause damage to them.

You are now finished……….

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When installing my UMI steering system I had to adjust the slack in my throttle cable. Following it to the throttle body I notice it was zip tied to the fuel rail. No biggy but the cable was rubbing the hard metal of the rail causing my cable to loose its protective plastic covering.

So I simply snipped off the zip tie holding the cable and used the rubber coated cable guide attached to the valve cover. Be sure the cable goes under the spark plug wires.

Notice how the cable now avoids the fuel rail without excessive tension.

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R&D SEAL KIT Pt. # 161-25000 $69.95

This Modification should NOT void your warranty.

 This is a simply item to install.  This kit seals up the area between the intake grate and pump shoe, which will help reduce cavitation and increase pump performance. While we are installing Seal Kit we will also be removing the entire pump. I chose to completely clean and replace the factory silicone during the Kit install. 

 If you have had a chance to look under a new 250X you will see alot of extra and poorly placed silicone.

First step I took was to remove the ride plate.

 

Then remove the Intake grate. You might need to pry this one off. Only use the joint between the grate and pump shoe to gently pry apart the two.

I then removed the pump.

I carefully cleaned the pump vein seal and the seat it sits in. Using a mild degreaser to remove the factory grease. It this grease that some have blamed cavitation on. Looking at mine it was evident that my seal had been leaking. Sand was on several part of the seal. See diagram with green highlighted parts for reference.

Also take the time to inspect your prop and pump case. Standard size is 155 mm but can be up to 156 mm due to wear. Aslo take the time to check clearance from the prop blade to the pump ring with a feeler gauge. You should not have anymore than 0.15 mm to 0.3 mm.

Using a a cheap skinny razor knife I trimmed away all excess silicone from intake and around the pump section.

This is what I collect from my clean up….

After you have completely cleaned the old silicone off your ski pump then install the Seal Kit.

Follow the instruction R&D has given you. USE BLUE LOC-TITE. Bolts that come loose can be sucked into the pump causing damage. Follow the torque values below under KAWASAKI Graphs.

Reinstalling the pump I used Windex to lubricated the rubber seal. It makes the seal slide into the seat easily and will dry away leaving a solid seal. Important for avoiding cavitaion problem from this seal leaking air into the pump. I then reinstalled the grate and plate using BLUE LOC-TITE. Once all that was torque correctly, I went on to fill all the gaps with a smooth even bead of caulking. Make sure to clean off any access silicone.

Below are some chart to help with the disassemble and reassembly.

Above diagram is from Kawasaki.com

Blue circles show where rubber hoses are connected.

Green rings are the areas that need to be cleaned free of any grease.

Red circle are showing the bolts that need to be torqued down to  87 in-lb and total 6.

Pink circles are showing the ride plate bolts that need to be torque down to 69 in.lb and total 8.

Not marked are the 4 pump bolts that will need to be torqued to 27 ft-lb.

Please Refer to chapter 11 in your Ultra 250X Service Manuel.

Completely finished the bottom looks like this.

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Information coming with Pictures.

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Heat Extractor Kit.  $59.95

This Modification could void your warantee. Oh and be safe and unhook that battery.

Let me explain what this modification does from R-Rated Performance.com

Lets start with the engine. It produces way more heat then any two stoke. I found that after running it hard that a high amount of heat starts to collectin the engine compartment. Often when idling I feel hot air coming from steering area. Perfectly normal on this boat since the motor and charger are contributing to this hot air. At this point the air intake is bathing in hot air along with the Relief Valve and Blow Off are venting into the intake system. At high speed the engine is then pulling enough air in that the ventilation tubes will draw in fresh cooler air. Its the slower speeds and idling that collect this hot air. Its that hot air that has to be sucked up by the motor before new air is pulled in through the ventilation hoses. These ventilation hoses are located in the front and the back of the engine compartment. See diagram below, vent hoses are circled in aqua blue. {14073}

So how does this new little item help.

Using the air rushing out the Releif Valve {16130} during low speeds and idle, the ventilators draw heated air out from the engine compartment.Since the Relief Valve is open the supercharger is blowing compressed air out this valve at a high rate. Its that blow off that this item uses to cause suction in the engine compartment drawing new cooler air from the front ventilation tubes. That way when you punch it again you will have a cooler air supply to draw from.

Locating the Ventilators in the rear was ideal as the hot exhaust boxes are right under them. This location also promotes cross ventilation inside the engine compartment.

Now some may say that you don’t want suctioning of the engine compartment during full throttle operation . Correct, full throttle operation is demanding a large amount of air to be supplied to the engine. At this point you want all the air possible to be availible to the engine.  That’s what’s so cool about using the the Relief Valve. The valve opens by vacuum produced in the intake manifold at idle and part throttle operation and closes when the throttle is opened wide enough to transition the manifold into a pressured condition.
The Blow Off Valve {16130A} is set up in the same manner though it is seldom used as much. This valve is used for a brief moment when you let off the throttle and the pressure exceeds the factor set boost limit. Though from testing the unit it has shown to start a slow leak at around 5 lbs of pressure. I don’t know enough to explain why this is happening but it seems to be standard with all 250X units.

Since this is a BLOG and not a professional review, Ill state my opinion that this modification will benefit the racing and recreational community. I would not recommend this modification to those who intend to jump waves or submerge the tail end of this boat.

 Ok enough of the chit chat, lets get to installing.

I used a flat head screw driver, a cross tip screw driver, a rivet gun, drill with 5/32 bit, wire cutters, 10mm socket with ratchet, small torque wrench and a box cutter or scissors. Use the two diagrams below as a color referenced chart. Ill add the number next to the name as to find it easier on diagram. This modification was simple but Ill describe it well so you’ll understand the complete install. Some items seem pointless but they do offer a benefit.

 

First carefully remove the seat base {blue 46075} by removing the four 10 mm nuts.

Then remove the duct hose adaptor {red 14073A} by using a drill and a 5/32 it to remove factory rivets. Careful to not loose the rivet backing inside the hull.  You should gently drill the rivet head and use something to catch backing of rivet.

Once the rivets are out then you can gently remove the duct adapter and the attached ventilation hose. {14073} Pay special attention to the cut out in the hull. It has a section of the hole cut larger to allow the srew down clamp head to fit into it.

Now move onto the stock air box to remove the two clamps holding the two valve ducts {yellow 14073 B&C}. Be especially careful removing these duct tubes, they break easy and are needed later. Place the supllied caps onto the airbox where the tubes were removed. {green 11038}

Then remove these same tubes from the the Valves. {Blue & Pink 16130 & 16130A} Use extreme caution on the valves when removing them. Be sure to cut the zip ties that hold the upper tube to the fuel rail. Set these tubes aside with clamps removed as we will need them later.

Loosen clamp holding the Valve {Pink 16130}. Then rotate it down 20 degrees be sure not to over rotate and pinch off the vacuum line {red 92191}. Be sure to re-tighten the hose clamp on the Relief Valve {green 92170}

Remove Blow Off Valve with a 10 mm socket. { blue 16130A} Careful with the gasket. Rotate valve 180 degrees and reattach so it faces away from hull side and toward the empty ventilation holes. Torque down bolts to the Blow Off Valve to 69 in lbs.

It is now time to route the duct tubes from earlier. Lets start with the relief valve. {pink 16130} Snake the hose under all inter-cooler and throttle body tubes to the rear of hull. Slip on a hose clamp and then the smooth section of hose. This deep down slope will help in preventing water from siphoning up into valve. Pull the remainding hose up through the first hole.

Install your extractor with the hose clams collected, remeber to line up clamp heads with indented hole portion. Also be sure to line the extractor divider plate from front to rear of boat. Tighten all clamps before insertingin it into hole.

For the Blow off valve I first attached the clamp and hose to the valve. {blue 16130A} Making a deep swoop inside hull I the routed the tube to 2nd hole and folowed the steps from the 1st extractor.

Dont get in a hurry and forget the calmps on the extractor as I had did in this photo.

Now you will need to rivet down the hose adapters to the hull. {red 14073A}

I used the provided zip tie to zip the two hoses together as to aviod rubbing against inter-coller and muffler.

Now reinstall the seat base and secure the 4 bolts holding it down. Oh and hook back up your battery.

When you are finished it should look like this.

Start engine to be sure that air is blowing out of 1st hole only. 2nd wont blow untill your out and operating at full throttle and hit beyond its set psi level. Even then only a small amout will flow.

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OK this is a simple modification that allows you to simple push a button to wake the ECU while in standby mode.

Warning this could void your warranty. REMEMBER TO DISCONNECT THE BATTERY.

Some information about the security feature of this ski.

Kawasaki issues two types of Keys with thisunit. One in orange will allow full performance of the unit. The other is a yellow key labeled SLO for limited performance of this unit. Also referred to as a learners key.

To start the unit you will need to insert the a key into the Immobilizer in the glove box. The Immobilizer is FOB activated and a small switch in the back of key hole is pushed when key is inserted. This reset switch is vital in telling the ECU that you want to start the ski. Once you here and audible beep the ski is ready to start by pushing the green start button on the handlebars.

If you hit the red stop button and shut down the ski, it will begin a count down to hibernate. If you reach that ECU hibernation point it will require you to reset the ECU by pushing on the key which hits the button in the key hole. No big deal right? WRONG it sucks opening the glove box every-time you wanna get going. Just does’nt look cool. What is cool is my push and go option.

What I opted to do was completely relocate the Imobilizer Switch and Key to under the hood and install a dash mounted push button.

How do ya do it? Simple. It is easier if you remove the steering to gain access to the under dash section that I mounted my button. I used a military grade waterproof switch. I ordered mine through Genelco Ind. 631.981.6670 Part# D1021-B5111-18 for $61.00.

Now its time to find the wires. You will need to locate the ECU and remove the entire mounting plate. Remove ECU and locate a white pluge with the color of RED, YELLOW, BLACK, GREEN, PURPLE and BLACK with YELLOW stripe. Once you find that plug you will want to snip the Bl/Yellow wire and the Purple wire. BE SURE TO LEAVE ROOM TO INSTALL CONNECTORS. Since I relocated my Immobilizer then I cut all wire then connected them back along with shrink tube.

This is where you will either T connect or direct connect to the these wires. I chose to direct connect as to avoid the reset being hit by objects in the hood area.

The range and green wire is going to my new dash button and have ignored the button wires to the Immobilizer. Please be sure to use a good glue lined heat shrink tubing.

Now put everything back together and try your new button. As long as the key is in then all you’ll need to do is push the dash button and start your ski. No more going into your glove box exposing your wallet and keys.

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 Warning, Disconnect the battery before doing this Modification. This may also void your manufactures warranty. Be sure to do this modification in a well ventilated area.

 After much dispute over fuel levels and when does the 250X run empty on fuel, I ordered up a new 250X fuel tank along with a R&D deep fuel pickup to test the results of what is really going on.

 Let’s start with a list of stuff used and for what.

3ft level to ensure fuel tank was level.

A new Jet Ski Stand with casters to hold tank and allow for movement to see sloshing effect.

A 5 gal fuel jug and siphon hose.

Brand new 250X fuel tank.

My stock pick-up unit.

R&D deep fuel pick up.

Starting with a new tank I cut open the top. Notice the thickness of the fuel cell wall…

I then installed the sending unit from my stock tank into the new test tank. Installing it as it sits in the stock tank. I then ran jumper wires from the stock plug the the fuel tank sending unit. Filling the tank with fuel until my low fuel buzzer turned off. Marking Tank.

That’s when I started draining fuel out of the tank using the stock pick up. Once bubbles started to be sucked up I marked the stock empty point. I then installed the fuel pick up and continued to drain the tank using the R&D fuel pick up. Once again marking the empty point.

Result’s? Buzzer went off at almost 7 gallons when sloshing. 5.5 when still and level. Stock empty with 2 gallons left and empty at 1.25 gallons left on the R&D fuel pick up.

OK so testing was fun but now lets get into the install and mod stuff.
I followed the R&D instructions closely.

Here are some pointers. Use a rag under fuel line when removing it because fuel will leak out of it. Unhook the reverse cable from behind when moving center dash aside and use a sharpie to mark point on can of white plug.

Carefully continue to remove per R&D instruction sheet.

Installing the billet pick-up was not easy. I had to use a rubber mallet to seat it correctly.

 

 So I got this far and decided to make a bit of adjustment. Notice the stock setting of the fuel pick-up . White plug on fuel pick-up lines up with black marking.

 What this does is allow the pick-up to rest in the center of tank where it is deepest.

I then bent the float arm to rest 1.5 inches lower in tank. Best if you lay the assembly on table then bend the float arm to obtain the 1.5 inch drop in the resting empty position.

I then reinstalled the fuel pick-up unit. Testing the fuel buzzer now sounds at 3 gallons left. Even during sloshing the tank. The V-shape of the tank help maintain the float pretty well. Leaving only 1.5 or so gallons to get more fuel.

Oh and for those who want to try a “fuel clunk”. It does seem possible but not to sure as to how it would mount securely to the fuel pump.

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UPDATE UPDATE UPDATE!!!!!!!!!!!!!

This morning I received a call from R&D Performance. Glen has been following our efforts with the 250X. He seems to be a fan of our work and has offered to help us get testing correct. His input has been valued in the past and will be looked to in the future.

Well in our conversation he commented on the Tank Test. He complimented our efforts and said it was a good write up. He then went on to explain how we missed a major and crucial aspect of our testing.

As he explained, R&D worked for some time testing this mod with the assistance of Factory Kawasaki. It was much more then a level bench testing as I had done. It was testing of actual watercraft moving forward in the water which makes the nose rise. This rise allows the fuel to collect in the rear section of the tank where the fuel pick up rests. Its this collection that allows more of the fuel to be utilized by the R&D fuel pick up mod.

We also talked of my modification to allow the fuel lever arm to trigger lower in the tank. Well by doing my mod it would work for the sensor but compromise the pick up of fully utilizing all the fuel it can reach. So we concluded that I should move the pick-up unit back to the stock setting but bend the fuel level arm 30 degrees to center tank. This is not a recommended modification but will I will be trying it to see if this IDEA works.

The only way to accurately test this small part would be to have this modification on during riding, running as much fuel as possible out of the tank, to see how much could be used before completely running out. This is running a risk of possibly running the engine lean. Something that I personal am not willing to try on my own. I’m sure R&D has a much larger resource for potential issues during their real world testing. Ive concluded that I’ll take Glens word on this one.

Regardless this outstanding display of respect and professionalism was awesome and we are so glad that Glen took time to help us get it right. Glen could have easily been upset with us and boasted his massive accomplishment to down our humble efforts but instead he offered a gentle and knowledgeable helping hand. This helps ensure Project 250X gets it correct and in return helps the Ultra community grow with solid knowledge.

Thank You so much Glen with R&D.

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Air Suction Block Off Kit. $39.90

If you have been following Project 250X on the forums, then you are aware I thought I had a failed ring. I was so convinced that I instantly posted a warning about improper break-in damage. Why? During a lake test I experienced a loss of RPM and speed numbers continued to drop. I opted to pack up and head on home. When doing my post ride inspection I noticed a small T connection melted on the top of my valve cover.

First step I took was to identify the affected area. See below

 

 Pink     = covers

Blue     = Reed Plates

Yellow = Reed itself

Red      = Vent ports 

Once I had this diagram I then started to look at the reeds and found that the position in which they were installed should only allow air to flow in and not allow exhaust out. 

So next I got on the phone with a proclaimed expert a great guy. Trusting and valuing his input, I was convinced that his explanation had to be accurate.  In his explanation, this port runs down to the crankcase, which allowed the positive and negative pressure to be balanced. Pos/Neg pressures will accrue from the piston moving up and down. This port helps balance that pressure. Having exhaust come back up meant that the piston wipe ring was bad, allowing exhaust to pass into the crankcase causing massive positive pressure, which forced its way up the port and relieved at the reed valve. 

 It was also explained that it aided in ventilating the crankcase. 

 Sounds good and had me convinced to the point that we began the process of a tear down for inspection. Something wasn’t settling well so I postponed the operation until more clarification was obtained.  

During conversations with owner of R-Rated Performance it was determined that the cover was indeed vented into the exhaust port. R-Rated then took the exhaust manifold off a 250 motor, he then stuck a pipe cleaner down the port to see it emerge from the exhaust port. This validated our suspicion and eliminated the IDEA of the port being contaminated from blow by into the crankcase. Doing more investigation it was determined that this ports main purpose was to dilute the exhaust gasses for emissions standards.  I tried the same thing with a green wire. Pushing it through till it popped out the exhaust port. So this ventilator has no effect on crank case pressure or does it go to the case. It only runs from the exhaust port to the Valve cover vent.

R-Rated Performance has released its newest part for tuners, the Air Suction Block Off Kit. Though this modification offers no speed gains or RPM improvements its value is in tuning accuracy. By using this block off the valve cover temps showed lower temperatures. In part from eliminating the back flow of hot exhaust. This elimination also avoids reed failure to occur causing ingestion into air box of exhaust fumes. Most importunately it allows for an accurate A/F ratio test in the exhaust by eliminating fresh oxygen into the exhaust before the O2 sensor.

 

 Talking with Rudy about any possible long-term drawbacks to blocking this emissions vent. Rudy said, “I’ve been using this item for some time on my 12F and 15F Turbo.” Rudy also said that the valve cover temperatures are consistently lower with ERV Block Offs. 

Lets recap on the purpose of this item. Ensure proper AFR reading to those running an O2 sensor. Stop the failure of the ventilators from effecting performance when running any kind of exhuast modification. Oh and this vent is not or can not contribute to the crank case pressure, that the job of the oil catch can.

Performance gain is none. This is NOT recommended for use unless tunning by O2 sensor or running an exhuast modification. __________________________________________________________________________________