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Project Pay2Play: My Eunos Cosmo has arrived!

Antoine

Administrator
306HP at the rears is a great number with the current setup Antoine. I think that's about 220Kw in the 'new money' which is similar to what I got with the Emanage Ultimate before getting rid of it

9 psi is low - sure it wasn't 0.9 bar? If it was only 9 psi then you have got about 50HP left in it before the turbos run out of breath.
Thanks for the feedback, Berty!

Good to know about the turbo limits...As for the psi, I don't want to push it too hard while I'm still mostly stock...Kawato-San recommends I upgrade the fuel pump and those rubber tubes that connect the intercooler pipes because they're probably as old as the car...He's concerned they might fail if the boost is increased...Eventually I want to upgrade those parts anyway along with the radiator and intercooler etc (aka Stage 2)...[emoji106][emoji106]


That's an even greater torque figure too! Always found it incredible how much more torque the 3rd rotor adds.
No doubt...Any idea how much torque a 13B-REW would generate with similar mods..?
 
Here's one with the legendary BNR Stage 3 turbo's. Crazy right?



What're your plans for a radiator? I desperately need one, but I've only found that PWR makes aluminum ones at the tune of nearly $1200 USD. They referred me to their Japanese branch, and they quoted me nearly Y140,000, AND it had to be special made, AND I'd have to wait until the "race" season when other custom radiators were being made.

I still have the stock radiator (unamused)
 

Antoine

Administrator
Holy 20B, that is crazy...I had no idea it was that drastic...Highly modified and the torque output is still quite a bit less than my lightly modified 20B with the stock turbos...Thanks for the info...Good to know!

As for the radiator...Good question...I'm in the same "boat" as they say...I'm still running the stock radiator and I dread getting stuck in traffic during the summer. That said, I do believe the F-CON V Pro is making the 20B run cooler...I haven't got stuck in traffic yet with the new setup...I plan on going for a long drive soon and I will be sure to post any observations. In terms of price...I've been quoted similar figures as well...I believe you can still order one from RE Amemiya and I think it's "order made" so that means expensive and you'll have to wait etc...There might still be a cheaper option from Koyo but it's copper and designed as a factory replacement (if I'm not mistaken).

I'm hoping I can get away with running the stocker for another summer while I save for a new suspension...I'm also now running the Okuyama Radiator Cooling Plate and "Sports Coolant" which I believe is helping to keep temps in check!
 
:
1991 Eunos Cosmo ECC 20B
Well done Antoine, some nice mods there. Does the HKS F Con keep the turbos working sequentially, nice one if it does. Great choice in wheels too, they would look fab on the Cosmo.
Darryl
 

Antoine

Administrator
Thanks, Darryl!

Yes...I'm still running the stock turbos sequentially and enjoying it...Glad you like those wheels too, they are still my top choice.
 

Antoine

Administrator
Update...I've taken the Cosmo out on a few runs after the recent upgrades and everything is running beautifully except...

-> If I turn the key to get electrical power (dash and radio come on), I now hear a loud clicking sound from the engine bay

-> The exhaust now produces a light popping sound after quickly accelerating and decelerating in 2nd gear...This probably has less to do with the gear and more with the process of quickly accelerating and decelerating I'm guessing...

-> Occasionally, If I accelerate for an extend period of time (say on the highway) and then let my foot off the pedal, I occasionally get a POP from the exhaust

-> Possibly unrelated to the recent upgrades...I'm now hearing an occasional loud squealing sound from the engine bay when I accelerate with the air con on...I'm suspecting this has to do with the belts and or the ac system

Other than that...The Cosmo is now doing an amazing job of keeping cool and I feel like the 20B is not having to work as hard as it did before to accelerate...This is especially noticeable when driving up mountain roads and when passing other cars...I now hit 5K a lot sooner than before which is great...I'm sensing that the Ol' auto box now has to work harder to keep up with the 20B's new found power and response...Eventually I want to "beef up" the transmission to better match and handle the 20B's increasing power.

Still, I've got to take care of my suspension first...Plus, I've got new issues to sort as mentioned above...Step by step as they say...
 
Those popping sounds from your exhaust are just small backfires, it's probably nothing at all the worry about as I'd take an educated guess and say the FCON and your tuner probably increased the injector duty cycles. No worries though, mine occasionally does the same on hard pulls, and I have a RE-A ECU and titanium exhaust. My FD barked and popped a lot with a Power FC. So as long as it not back firing excessively, you should be fine, and grin slightly when it happens, especially if it happens next to a Prius.

Back firing and rotaries go hand in hand like peanut butter and jelly.

As for the air con squealing, your belt probably just needs tightening. Just make sure you don't tighten it too much and snap the very skinny tension bolt....like I did. My car is doing the same same thing and it's extremely annoying because it's super hot and humid down here. My issue is that my belts keep getting stretched. Bought 3 more last week, waiting on delivery lol. Another temp fix it keeps squealing is to try and rub a bar of soap on the ribbed part of the belt.
 
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:
'86 RX-7 Base, '79 RX-7 GS
-> If I turn the key to get electrical power (dash and radio come on), I now hear a loud clicking sound from the engine bay
Is it a single click or several? I'm not familiar with how the FCON is installed on a Cosmo but perhaps it's a relay switching on.

-> The exhaust now produces a light popping sound after quickly accelerating and decelerating in 2nd gear...This probably has less to do with the gear and more with the process of quickly accelerating and decelerating I'm guessing...
This is likely just a result of the tune and can be caused by more or less excess fuel in the exhaust.

-> Occasionally, If I accelerate for an extend period of time (say on the highway) and then let my foot off the pedal, I occasionally get a POP from the exhaust
Same as above.

-> Possibly unrelated to the recent upgrades...I'm now hearing an occasional loud squealing sound from the engine bay when I accelerate with the air con on...I'm suspecting this has to do with the belts and or the ac system
Definitely check the belts.

Other than that...The Cosmo is now doing an amazing job of keeping cool and I feel like the 20B is not having to work as hard as it did before to accelerate...This is especially noticeable when driving up mountain roads and when passing other cars...I now hit 5K a lot sooner than before which is great...I'm sensing that the Ol' auto box now has to work harder to keep up with the 20B's new found power and response...Eventually I want to "beef up" the transmission to better match and handle the 20B's increasing power.
I'd just monitor how the transmission shifts. Is it taking longer, making more noise, etc. Those are clear indicators the transmission isn't up to the task.

Still, I've got to take care of my suspension first...Plus, I've got new issues to sort as mentioned above...Step by step as they say...
I would say most of those aren't issues. Trying to get more power out of the engine is going to result in some interesting noises.
 

Antoine

Administrator
Those popping sounds from your exhaust are just small backfires, it's probably nothing at all the worry about as I'd take an educated guess and say the FCON and your tuner probably increased the injector duty cycles. No worries though, mine occasionally does the same on hard pulls, and I have a RE-A ECU and titanium exhaust. My FD barked and popped a lot with a Power FC. So as long as it not back firing excessively, you should be fine, and grin slightly when it happens, especially if it happens next to a Prius.

Back firing and rotaries go hand in hand like peanut butter and jelly.

As for the air con squealing, your belt probably just needs tightening. Just make sure you don't tighten it too much and snap the very skinny tension bolt....like I did. My car is doing the same same thing and it's extremely annoying because it's super hot and humid down here. My issue is that my belts keep getting stretched. Bought 3 more last week, waiting on delivery lol. Another temp fix it keeps squealing is to try and rub a bar of soap on the ribbed part of the belt.
Thanks for the info and suggestions...The popping sound / sensation is quite mild most of the time and I've heard a noticeable "POP" just a couple times so far...I do like the sound and it's funny you mention backfiring near a Prius...I was thinking that would be fun...It would be great to see the reaction on the Prius Driver's face!

That said, is there anything that can be done to reduce the backfiring..?

Is it possible that flames are coming out of my exhaust when it backfires?

Thanks as well for the air con info...I'm hoping it's just a loose belt issue or something that is easy and inexpensive to fix. This is the first time this has happened and I've driven in quite a few Japanese summers now...I'm planning on doing some fixes and upgrades after the weather cools down...If it's not an emergency issue, I'll wait until then to sort it.
 

Antoine

Administrator
Is it a single click or several? I'm not familiar with how the FCON is installed on a Cosmo but perhaps it's a relay switching on.
Several and it seems to speed up the longer I let it continue...It does sound like something clicking / switching on and off...It's definitely loud!


This is likely just a result of the tune and can be caused by more or less excess fuel in the exhaust.
Is this unavoidable with my setup? Can it be tuned out? Is it causing any damage?


Definitely check the belts.
Will do!


I'd just monitor how the transmission shifts. Is it taking longer, making more noise, etc. Those are clear indicators the transmission isn't up to the task.
Will do...I think my transmission can handle the additional power for now but anymore and I've been told I should consider upgrading the transmission internals because it might start slipping...Unfortunately, it's an expensive procedure in Japan. Ultimately, I want to do it though...Just need time and money as always...


I would say most of those aren't issues. Trying to get more power out of the engine is going to result in some interesting noises.
Thanks for the input and reassurance...Very true...I'm looking forward to the challenge and the reward...So far so good!
 
The backfiring probably could be tuned out, but that might mean leaning out the tune which would be a big no-no. Going back to the stock exhaust would quiet it down, but who wants to do that right?

Doubtful that you're shooting flames, but if you ever notice a quick "glow" in your side view at night you might be. Either way, the tune is probably a lot more helpful and harmful. My FD never threw flames are far as I know. I had a S14 that threw fat flames at higher altitudes (mountain driving), never had any issues.
 

Antoine

Administrator
The backfiring probably could be tuned out, but that might mean leaning out the tune which would be a big no-no. Going back to the stock exhaust would quiet it down, but who wants to do that right?

Doubtful that you're shooting flames, but if you ever notice a quick "glow" in your side view at night you might be. Either way, the tune is probably a lot more helpful and harmful. My FD never threw flames are far as I know. I had a S14 that threw fat flames at higher altitudes (mountain driving), never had any issues.
All good points, thanks for the input...Much appreciated! (2thumbs)
 
Hey Ant I have a question about your intake. I ordered the AutoExe unit also and its arriving soon. Did you keep that stock air diverter tube there after you remove the stock intake?

Do you think the intake is getting sufficient air being behind the headlight? I was thinking of cutting out a section of that rubber strip thats on the underside of the leading edge of the hood.
 

Antoine

Administrator
Hey Ant I have a question about your intake. I ordered the AutoExe unit also and its arriving soon. Did you keep that stock air diverter tube there after you remove the stock intake?

Do you think the intake is getting sufficient air being behind the headlight? I was thinking of cutting out a section of that rubber strip thats on the underside of the leading edge of the hood.
Sorry for the late reply, I've been super busy this week! Did your intake arrive? If so, how do you like it? I've had mine for years now and it has been trouble free...As for your questions...Do you mean this large open rubber tube coming up from the bottom there..?



Is so, yes...I've kept it there...What are you thoughts? Better to keep it or not? I'd prefer a cleaner look but I haven't thought yet about how to achieve that...Hmm...Food for thought!
 
Yup that's the tube I'm referring too. I don't really see it doing any harm being there. I was just wondering if there was a way utilize that pipe with the new intake, I haven't gotten yet so I was unsure of the fitment.
 
:
'02.5 Mazda Protege5
Any updates Antoine? Just spent a couple hours reading through the thread, I have to say it's definitely one of my favorites. I'm a member of many different forums, yet I haven't seen a build thread so nicely done with tasteful mods that maintain an elegant style while improving the driving experience (thumb). I've always had a fancy for rare "JDM" cars, and the Cosmo is a beautiful example. Hope all is well!
 

Antoine

Administrator
This is a 20b with a Flame "problem" Antoine! Popping is fine enjoy it! And, if you are driving it enthusiastically - it will pop a flame or two! Kramer has been known to! Much to the delight of the RX7 following me up Thunderbolts Way!

Kramer
Haha...Thanks for the enthusiastic response, Kramer! Glad to know the popping is not an issue...I don't hear the noise that often but it has become a nice surprise when it happens!


Any updates Antoine? Just spent a couple hours reading through the thread, I have to say it's definitely one of my favorites. I'm a member of many different forums, yet I haven't seen a build thread so nicely done with tasteful mods that maintain an elegant style while improving the driving experience (thumb). I've always had a fancy for rare "JDM" cars, and the Cosmo is a beautiful example. Hope all is well!
Wow, thanks for taking your time to read my thread! I really appreciate your feedback and kind words, it means a lot to me!

As for updates, I admit I've been neglecting my own build thread here but that's because I've always got a million things I want and or need to do and only so much time! That said, I've been planning and saving for future upgrades. Actually, the Cosmo is currently at TCP Magic getting a check up after a long winter nap. I will have to take care of the "shaken" (Japanese mandatory car inspection) by September 2015 and that means spending lots of yen just for approval to drive on the street (which is pretty depressing).

One upgrade that I may HAVE to do otherwise I might not pass shaken this time is suspension. Kawato-San told me two years ago when he last performed shaken that my Cosmo's alignment may not pass inspection this time due to aging springs, shocks and bushings (which I haven't changed since purchasing the car years ago). I would like to go with a custom Made in Japan coilover setup which Kawato-San can supply but as always...You've got to "Pay to Play" ;) Obviously it's going to cost a pretty penny for such a suspension but even if I just replace the shocks and springs, it's still going to run me plenty of yen (parts and labor can be a lot more expensive in Japan compared to other countries).

Stay tuned to see what path I take...I will most likely have some juicy updates for this summer and or fall and thanks again for your support! (rockon)
 
:
Mazda Axela 4WD GT (Lexie)
Any chance you are driving your beast up to Hokkaido this summer?


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