MKTurbo Black Friday Sale TIME
#762
Boost Czar
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he's down 4-5 psi at 3500rpm from redline. probably would have hit 200tq on that plot had it hit 12psi at 3500.
should be more power than that on a dynojet assuming a 1.8L. I'd expect around ~230-240rwhp.
i was making 160-170rwhp at 6-8psi on my 1.6L dynojet.
should be more power than that on a dynojet assuming a 1.8L. I'd expect around ~230-240rwhp.
i was making 160-170rwhp at 6-8psi on my 1.6L dynojet.
#764
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Normal wastegate preload (3 full turns)
Using an MBC on those pulls but will be getting the EBC hooked up over the next couple days. I did port the housing earlier (mild) and opened up the flapper hole a bit (again mild) but working on something to help the flapper open more to get out of the way. Hopefully that will help resolve any boost creep and make usable boost pressure lower.
I'm still trying to understand how an EBC will help resolve boost creep (if it does) but I'm still reading. I understand if you can make the boost flat then you can raise boost pressure and hopefully it'll make it earlier (to a point).
Still a work in progress.
#768
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I've been bogged down with work so haven't driven the car in a while. I will post a log soon hopefully. I pretty much have a for the most part flat 4th gear boost curve as well as 3rd. The only gear where I have slight boost spiking worth considering is 5th. I think that may be acceptable though. Over the weekend I was also playing with timing and took it out for back to back pulls in super low humidity 100degree heat and was able to eliminate any possibility of knock. I got to thinking as this car will get some track day work and started reading about using fuel in decell to cool the pistons. Rather than dumping a ton of fuel I set the timing to 12 degrees in the decell high vacuum area of my spark map. This way I just don't burn all of it. Maybe this is slightly off topic but is anyone else doing this. I searched around and saw where soviet talked about it a little but does this sound ok? The car is very responsive coming out of that zone and still engine brakes well and returns to idle well. There isn't any knock or insane over fueling.
#770
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<p>
</p><p> </p><p>Yea, I'm working on it. I ordered a spare turbo and it'll be here in a day or so and I'll have something to work on off the car. I'll do a little more porting and enlarge the wastegate hole a bit more. I've also ordered some parts to fab up a better flapper housing that I hope will let the flapper open up like the TD04 that <span>@aidandj</span> showed in post #729 here https://www.miataturbo.net/miata-par...7/#post1250325.</p><p> </p><p> </p>
#771
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<p></p><p> </p><p>Yea, I'm working on it. I ordered a spare turbo and it'll be here in a day or so and I'll have something to work on off the car. I'll do a little more porting and enlarge the wastegate hole a bit more. I've also ordered some parts to fab up a better flapper housing that I hope will let the flapper open up like the TD04 that <span>@aidandj</span> showed in post #729 here https://www.miataturbo.net/miata-par...7/#post1250325.</p><p> </p><p> </p>
#772
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<p></p><p>Flange with flapper assy; : atpturbo.com</p><p><img src="http://cimg9.ibsrv.net/gimg/www.miataturbo.net-vbulletin/483x401/80-t3_5_bolt_flapper_flange_49c41d444c6500b173e6dfc04 c7c3aade4fbe643.png" title="" /></p><p>Transition tube; http://ATP-FLS-091</p><p><img src="http://cimg0.ibsrv.net/gimg/www.miataturbo.net-vbulletin/343x452/80-transition_tube_e4c61e9d75372085e4a365247304458a60 90011c.png" title="" /></p><p>2.5" Stepped V-Band; : atpturbo.com</p><p>There's only 2" to work with without completely changing the downpipe location (not something I'm keen on now). The flange is .750" and the 2.5" V-Band is .500" so the transition tube will get sliced down a lot to the .750" it needs. But, it'll let the flapper open up the full amount of the actuator stroke and eliminate that as a bottleneck.</p><p>Alternatively, I'll hack up the flapper housing that comes with the turbo. I have a couple ideas. Parts are out for delivery today then I'll get them to my welder.</p><p>I ported my housing earlier (not as severe as you I suspect) and opened up the hole a little but I think the hole really needs to be opened up more like was mentioned earlier by deezums.</p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p>
#774
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<br /><br />We can agree to disagree. I happen to think the flapper can't open far enough. If I'm wrong then I've spent money foolishly. Not the first time. <br /><br />No, not sure on the hole size because the stock flapper is not centered on the hole so I only opened up towards the heavy side about 2mm.<br /><br />I'll pull the spare turbo apart and open the hole properly and centered on the flapper. <br /><br />In the meantime, I'll have the new flapper housing back and can try it. I'll post logs.
#775
SADFab Destructive Testing Engineer
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<p>Easy test.</p><p>1. Pull downpipe.</p><p>2. Use compressed air to open the wastegate. say 20psi so you know its opening all the way</p><p>3. Measure where the wastegate opened to.</p><p>4. Put on downpipe.</p><p>5. Repeat 2 and 3.</p><p>6. ????</p><p>7. Profit</p>
#776
mkturbo.com
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Last edited by shuiend; 07-23-2015 at 01:21 PM.
#777
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I use a see thru ruler to measure stroke on the wastegate can.
I actually had to replace the k03 on a mini cooper the other day, it uses vaccuum to power the wastegate so you have to preload it around 8mm of stroke or so open or it overboosts. My ruler worked well for that, there's zero room for anything in that car.
You should be able to do the same with our turbos, just smack one end of the ruler against the compressor housing as a good solid immobile refrence or something and measure the total stroke using air like Aidan described.
Our downpipe is incapable of restricting the range of the wastegate flapper though, the v-band housing can be, but not the downpipe.
I also think the extra flapper is a waste, but maybe the 1.8 really does flow that much more, I doubt it.
I actually had to replace the k03 on a mini cooper the other day, it uses vaccuum to power the wastegate so you have to preload it around 8mm of stroke or so open or it overboosts. My ruler worked well for that, there's zero room for anything in that car.
You should be able to do the same with our turbos, just smack one end of the ruler against the compressor housing as a good solid immobile refrence or something and measure the total stroke using air like Aidan described.
Our downpipe is incapable of restricting the range of the wastegate flapper though, the v-band housing can be, but not the downpipe.
I also think the extra flapper is a waste, but maybe the 1.8 really does flow that much more, I doubt it.
#779
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Yeah, I use a ruler butted up against the compressor housing/wastegate bracket. Otherwise, there's really no reference to tell what's going on.
I didn't spend much time jacking with that, I checked the range of motion of the unimpeded can, then fixed it up, preloaded it slightly and checked the range of motion again.
I'd guess mine is around 3/8" of stroke, short enough that I don't use all of the relief for the flapper I made, I remember that part.
I didn't spend much time jacking with that, I checked the range of motion of the unimpeded can, then fixed it up, preloaded it slightly and checked the range of motion again.
I'd guess mine is around 3/8" of stroke, short enough that I don't use all of the relief for the flapper I made, I remember that part.