TheAxeGod Posted April 18, 2008 Report Share Posted April 18, 2008 Damn guys that did my head did a crappy a** job with my jet valves by welding them closed.... UPDATE I did get the engine running it was out of time by one tooth i guess, but i went to test drive it, got to 3k RPMs and two of my jet valves broke and broke off the piece of the rocker arm but they should still function fine, my question is, i'm goign to ace to just get some solid bolts to fill in the holes this should be fine I assume but wanted to ask what any of you guys have done before, Let me know if that'll work, but I don't see why not seeing how they rigged up my jet valves... -Axe Link to comment Share on other sites More sharing options...
Wolf87Conquest Posted April 19, 2008 Report Share Posted April 19, 2008 The jet valves should be completely removed...so no piece can break off later with heat cycles etc. I wouldn't put just any bolt in...it should be a hardened one to withstand the heat/ cooling cycles it will encounter. You also don't want it to be too long...for obvious reasons. There might be a allen head or other designed plug for this. Wouldn't hurt to check around with parts suppliers online to see if they are available. Rockauto.com and Rockville Mitsubishi are just 2 of the places you could check. I've had good results getting parts from them. Rockville Mitsu has a phone number on their site if you might like to call em. If you do, talk to Mike. Link to comment Share on other sites More sharing options...
TheAxeGod Posted April 19, 2008 Author Report Share Posted April 19, 2008 (edited) Found these via Google...interestingly enough, these are the only JV elimination kits they offered....lol can't beat it for 26$ Hopefully the car is good to go after this! Might want to move this link to FAQ, I can't be the only one doing this without a D50 head. -Axe Goodson Jet Valve Elimination Kit for 2.6 Edited April 19, 2008 by TheAxeGod Link to comment Share on other sites More sharing options...
JAinsworth Posted April 19, 2008 Report Share Posted April 19, 2008 Found these via Google...interestingly enough, these are the only JV elimination kits they offered....lol can't beat it for 26$ Randy aka Dad beats that price hands down You can't "just stick a bolt in" regardless of composition. The jve bolts have an o-ring on them. Dad from this site sells the JVE kit (the correct 4 bolts with the o-ring) $12.95 plus shippping. Jimmy Dad...For Starquest Parts Link to comment Share on other sites More sharing options...
Zack_Morris Posted April 19, 2008 Report Share Posted April 19, 2008 DO NOT PUT BOLTS IN. There is a specialized "Jet Valve Elimination" kit. You can get it from www.enginemachineservice.com If the jet valves are broken off they will not work anymore. If you ask me, I would recommend you getting them out as soon as possible to prevent any further damage to your valvetrain. Link to comment Share on other sites More sharing options...
TheAxeGod Posted April 19, 2008 Author Report Share Posted April 19, 2008 Sadly, we were in a hurry and I didn't check dads site, even though I bought all engine parts from him lol....oh well, would have been better to get it from Dad too...but I was in a hurry, but I know now! Thanks. -Axe Link to comment Share on other sites More sharing options...
Shelby Posted April 20, 2008 Report Share Posted April 20, 2008 what the hell did you mean by "weld'd the jet valves" and then not remove their operateing arms, Link to comment Share on other sites More sharing options...
dj_justice Posted April 20, 2008 Report Share Posted April 20, 2008 (edited) Just curious why does everyone remove the Jet valves. I would think the mitsubishi engineers put them there for a reason so why take them out? Or maybe the mitsubishi engineers never wanted to have them there in the first place. Maybe chrysler told mitsubushi they would re enact the bombings of hiroshima and nagasaki if they didnt put the jet valves in. Thats my theory when it comes to the throttle body injection anyways. Edited April 20, 2008 by dj_justice Link to comment Share on other sites More sharing options...
Wolf87Conquest Posted April 20, 2008 Report Share Posted April 20, 2008 Lol, I know what you mean d j...but, the jet valves are there to help promote mixture homoginization. Under boost conditions, this can do wonders to get good mixture to acheive as complete a burn as possible. Removing the jet valves, after all the years they've been in the engine and lots of miles, being a bit worn out will keep them from destroying the engine once the jet valves fall apart. You could argue the point that the jet valves are an emissions issue...probably the main reason the engineers put em in. Removing them will hamper mixture homoginization some, but more on the upper rpm range under high boost than in cruise with a few pounds boost. As for the TB...well...it is odd for sure. I like to think of it as this...this car was designed to be a road race car. Typical race car builds are simple, but effective to do the job required. Multi port injection is quite complex, with each individual injector timed properly makes the computer system and the sensors needed to feed info to the ECU complex as well. The TB on these cars is quite similar to a carb....but having two injectors, and using a small one, then having a larger one come into play at a designed point is effective...and simple. It does work well enough...and simple...but, yeah, it sure is kinda odd. Makes you wonder when it was designed if the person was drunk or something. It works...that's what matters. Link to comment Share on other sites More sharing options...
mikec Posted April 21, 2008 Report Share Posted April 21, 2008 The jet valves were introduced to the original carbureted 2.6 engines as the "MCA Jet Valves" - you sometimes see those stickers on early 80's Mitsu built cars. They shoot air into the cylinders, along the sides of the cylinder wall to help "swirl" the air+fuel inside the cylinder. This makes the air:fuel mix better - an issue with carburetors - for a better, more consistent burn. That increased engine efficiency (MPG and horsepower) and really helped emissions. Remember, most design changes in engines over the last 30 years or so have been driven by emissions laws. Simple carburetors got replaced by "feedback" carburetors with early style O2 sensors... and these were replaced by throttle body fuel injection... which in turn got replaced by port fuel injection. Each change improved emissions by getting the air:fuel ratio closer to optimum at all times, getting better air+fuel mixing, etc. A side benefit to the emissions laws (and the CAFE MPG requirements) has been research on combustion physics to squeeze out every last bit of horsepower or MPG from the fuel. Other benefits include better high-altitude running (remember "re-jetting" carburetors for high altitude operation?), better cold-temperature running - port fuel injection especially - shooting the fuel right into the cylinders rather than trying to move a mixed air:fuel mess through pipes... some gas always condenses out of the mix, puddling in the intake manifold, instead of going into the cylinders. That's why carbs needed "chokes" and heated intake manifolds. When Mitsu turbocharged the 2.6 engine at the StarQuest's introduction, it left the jet valves (and other emissions bits already on the engine) alone. The carb was replaced by an "electronic carburetor" system: i.e. throttle body fuel injection. That was both because of boost pressure (using a carb with boost pressure requires special carbs or special mounting tricks; it's a bit of a pain really) and to meet emissions. The throttle body setup on StarQuests really is just an electronic carburetor... that's why the fuel system is independent of the ignition module too. Years later, when Chrysler started using the 2.6 engine in minivans and other vehicles, the then-current carburetors worked better (at getting the right air:fuel ratio and at actually mixing the air and fuel together) than older carbs... the jet valves were no longer necessary. mike c. Link to comment Share on other sites More sharing options...
Indiana Posted April 21, 2008 Report Share Posted April 21, 2008 I've welded up jet valves and they are still in my car and being used I drove it today. I used a TIG and a stainless rod, actually Kurt did it for me. Hack welders I'm sure could screw it up but that's what hacks do best. http://www.b2600turbo.com/jet_valves.htm the factory info is at that link Link to comment Share on other sites More sharing options...
TheAxeGod Posted April 24, 2008 Author Report Share Posted April 24, 2008 Well, I have the JVE kit installed in the last three cylinders, and so far, I drove to work (50 miles) and everything was kosher. BUT, to feel safer about that weld breaking, I do wnat to remove the first jet valve without disassembling the head...i tried everything and can't get anything on it, anyone have ideas? Only thing I thought might work is a 14mm 1/4" drive socket, my 3/8 do not fit, nor can you get a wrench on the head of the jet valve. The top of the valve is missing, its welded at the nut portion...seems to run fine, but I just don't feel safe since the other two broke. Thanks for all the help guys! -Axe Link to comment Share on other sites More sharing options...
macrophage Posted April 25, 2008 Report Share Posted April 25, 2008 The jet valves are steel and get hotter than the head when that happens it cracks the small area where the jet valve and or intake/ exhaust valve are closest. Link to comment Share on other sites More sharing options...
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