Well, aside from getting my mini back on the road after a fluke wheel bearing failure. Or Dave getting my bottom end built on my fast road 1275. Rx7 turbo upgrade! I'm swapping out the non divided 81 housing for a 1.0 divided housing. I previously dynoed 405rwhp, but the smallish exhaust housing chokes power on top end. Then I started digging into benefits to twin scroll turbos (I have a twin scroll manifold to reap the benefits) and I can expect a pretty significant gain through the whole power band. Sounds like any lag associated with the larger a/r will be offset due to the twin scroll as well. I use to run a 62-1 way back in the day with a 1.0 p trim and it would light them up in 3rd gear. I now run a pt6266. Figure I might as well go open dump wastegate like I use to run on the race rx7 and squeeze another 20hp out of it too. All this to say, I got into a street altercation with a c63 amg Mercedes (the 500hp turbo v8 kind) ane we tied. The next time I see this guy he's going down hard.
Man, and I thought it ran pretty damn hard already! 71.gif
Previous owner has the exhaust choked up pretty bad. Turbo housings aren't expensive luckily, and the open dump wastegate is just me welding up where it's plumbed into the exhaust. Most guys tie it back in for noise, but wot all the way to redlne is loud as hell to begin with. I'll be loud and sound like a super bike all at once now. Regular cruising won't be affected. I anticipate a 50hp gain at peak and significant improvements from 4000rpms all the way to 8k.
Is this an rx7 or a mini. Old rx7 or modern version
A 94 rx7.
Two words:
Nitrous oxide
I had a 50 shot on my RX7 (a wet setup, the kind that sprays extra gas with the N20) and I am here to tell you it makes a Turbo Rotary into the Incredible Hulk.
While being Jetted for only 50 more HP, my ass dyno and racing against friends results leaned more towards 100 more HP. When I would be neck and neck with a fast car without the N2O when we ran again with it on, I would be 2-3 bus lengths ahead. It was insane!!
Why? Because it is COLD and rotaries love cold, turbo rotaries love cold even more. Bonus, make a trick setup where you have a second 1-2 gallon gas tank dedicated for the N20, keep 100+ Octane in it. I did not do this, I used the existing fuel system and it worked great but I have heard great things about this setup.
If you do not want to go that crazy consider a Alcohol / Ethanol injection setup, that helps with detonation which means you can turn the boost up more and make more safe power.
Man, you are really making me miss my old FC. I wonder if the guy that bought it either blew it up or killed himself.
For you guys that do not know, my 1987 RX7 had the same engine as Dan swapped in except it had a $10K rebuild done, all the best of everything added to it. It was built for huge boost like 24 PSI but I only ran 1 bar in it but would push to 18 PSI when I wanted which = 480 RWHP in a 2600 lb car.
I once raced a Porsche Carrera GT in low boost from 60 MPH up to 175 MPH and the Porsche was slower than my car. At track days I would push Ferrari F360 Stradale's around road courses and freak them out. This car was a monster, and I regret selling it, until I hear others complain about problems. ;D
I'll never do nos but water injection yes. In fact I've installed it before and the results are really good. Doesn't effect power but definitely a reliability mod in case I decided to tear up the Arkansas roads one weekend.
I had the N2O setup on my FC back when I was into drag racing. Once I caught the Autocross and track day bug I yanked it off, the bottle was not allowed in the car for those events and the moment a tech inspector saw the actuators under the hood he would freak out and run to the back of the car to make sure the bottle was not there.
Plus I noticed a bit of an attitude from some tech inspectors. I did not need that BS so I pulled the kit off and sold it to a guy with a Caddy CTS-V.
Remember too, the H2O/Alcohol setup is a power adder, it makes the charge very dense and cold it also keeps things clean, you can run a few more lbs of boost using it and that alone is worth some decent power.
I never used one, I read a lot on it and it was not something I wanted on my street car that gets track driven. I was happy running lower boost and slightly lower timing and less HP. I just wanted simplicity.
You have the OMP on that thing still or are you premixing?
The kit I installed was purely for water. We even dynoed it, but since we didn't change anything else the results with it on vs off were identical, except temps were way lower with the water. After reading up on methanol am seeing you are suppose to run a 50/50 mix and it's the equivalent of running 116 octane. Now I'm thinking about doing that and bumping the boost up a couple psi. Kits are reasonably priced at around $400 for the higher end setups.
Omp is there, but I premix. The previous owner did as well.
Jim, I've been searching high and low for dyno graphs on anything comparable to what I'll have. Best I could find was a pt6265, which is the old technology later replaced by the 6266 that's said to be much more efficient. I also assume the blades are 65mm vs 66mm. Anyways he made 470rwhp at 19psi on water/meth on 91 pump. Not certain about the wastegate plumbing either. Then there's the 550rwhp+ at 25-30psi crowd which isn't going to be me. I'll go 3 rotor to get those numbers more reliable.
Yup 450-475 RWHP is all you are gonna squeeze out of a 13B-REW safely and reliably. Once you start going over 20 PSI the engine needs to be built up, most importantly doweled.
I think the H2o injection is a very solid idea and great insurance.
Excited to see what you come up with.
Go fast parts are always fun and exciting!
Dude, there's a guy with a MEAN sounding black RX7 here in the Dayton OH area. He is always ripping it along the backroads by my house. Love the sound of it. I can only imagine how much fun they are to blast around in.
Funny to think my 1275 is the same displacement!
Well F1 cars run 1600cc's. Your mini is basically almost an F1 car. My pickup has 5654cc's...sooo... basically I drive a spaceship to work every day.
Quote from: 94touring on August 25, 2016, 05:23:43 PM
Funny to think my 1275 is the same displacement!
I LOVED pointing out to Harley guys my RX7 had a 80 cubic inch engine in it make 550 HP. I melted their minds.... almost as much as the Ferrari driver on a road course seeing me eat up his mirrors.
My research on water/meth injection continues. Rx7club has a whole section dedicated to it, who knew! So sounds like 20psi on straight water is safe and as crazy as it sounds 30psi on water/meth at a 50% ratio. Now I'm considering 18, maybe even 20psi on water/meth. The other consideration is where to inject it. Pre or post turbo. I found a graph of a guy running 24psi that has a same day comparison. The power curves are slightly different between the two. Minidave which one looks better to you, since you're the power curve connoisseur! Red is pre turbo and blue is post.
Link cause I can't save to my phone for whatever reason: http://farm8.staticflickr.com/7008/6850333663_8c1e98f17e_b.jpg
Well, at first glance pre-turbo makes more power - probably because the action of the turbine blades mixes the liquid well with the air charge.....however - you are running water thru your turbo. OTOH, you'd only use this on hard runs, not constantly, so I don't think that would be a problem.
Also, you can see the power comes on sooner with the post turbo spray, so I guess it depends on where/how you're going to use it. Will it be an on demand style, keyed to boost or mechanically to the throttle or what?
I'd have it kick in at 10psi likely, and only that early so it's at full spray by time I'm over 15psi. Day to day driving I'm rarely over 10psi. I just couldn't decide if the midrange gain outweighed the lengthy top end gain.
Well, as you know I'm all about that torque, because you don't drive your car wide open all the time. rather you're mostly in the mid range in day to day driving.
Depends on what you want of course......
This is one of the kits I'm looking at.
http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=161756170712&category=42604&pm=1&ds=0&t=1472321265569
I know several guys who use these on MINIs, usually with water/meth.....
In the midst of reading today and pondering what my timing should be over my current 15psi discovered that the fuel maps on my ecu peg out at 19.7psi. I do have a 3 bar map to exceed that, but have to change the ecu maps to get fuel. Looking like my datalog kit I bought for tuning does allow some kind of editing to achieve this but haven't found a good tutorial yet.
I never ventured over 18 psi so I cannot help. Typically ypu pull a little timing out as the boost goes up to prevent detonation. Using ethenol water injection gives you some liberties there though so I would do some research on club. Look for Pluto on there that is Steve Kan from Texas and he knows his stuff. Avoid BDC at all costs he built Tony Farkas' car that I bought and it was a habbled mess, makes skips work look like and F1 team.
Yeah typically it's a degree per psi but going up 5psi with water/meth is a different ballgame. I've met Steve several times back when I put on rotary car shows.
After more research am thinking a split system that injects pre and post turbo. Ideally you have some pre injection to keep the turbo at it's peak efficiency, gaining big top end power, but the more you spray will cause a lag simply due to friction of water on the impeller. This is why the dyno graph with pre injection has a lower midrange as the turbo spools slower. Guys are dividing it up and getting best of both worlds.
Ta da
It's ............................................a snail!
If you put an 'S' on the back, we could say "Hey, look at that escargot!"
Nissan made an 'S Cargo'!
(https://upload.wikimedia.org/wikipedia/commons/2/23/Nissan_S-Cargo_001.JPG)
Yikes!
My 'escargot' joke was a feeble attempt at trying to tie in with the movie quote thread. In the film 'Trading Places', an 'S' car go joke was told by a not so funny 'stuffy' character. :-[
That is alright, John.
The Nissan was reputed to be a bit of a snail in performance.
Here is something rotary powered for Dan or Jim to maybe enjoy:
http://www.wirewheel.com/1992-Maxton-Rollerskate-for-sale.html (http://www.wirewheel.com/1992-Maxton-Rollerskate-for-sale.html)
Not my cup of tea but I did see a cosmo for sale recently that would be cool.
Quote from: 94touring on September 08, 2016, 03:39:14 PM
Not my cup of tea but I did see a cosmo for sale recently that would be cool.
A Cosmo would be cool, you could make a hell of a 600+ HP sleeper out of one, except one problem they are all Automatics. I may be wrong but I have never seen or heard of a manual Cosmo.
That Rollerskate is a couple towns north of me. That 12A rotaty may be making 100 HP on a good day, I am sure the car is light and nimble and fun... and noisy as hell.
Didn't know the cosmos were only automatics, but I'd probably use it as my family car/grocery getter/airport car anyways. Then smoke everyone on the street.
I am 90% the Cosmo only comes with an Auto. The problem then is how much can the slushbox take HP wise?
It is super easy to get 550 HP out of a 20B, can the rest of the car handle it. I think they have about 300HP stock.
Early Cosmos were 5 speed manuals - later cars were a lot larger and I don't know about the transmichigan.......but I can't image it being impossible to swap the gearbox along with the engine.
Yes the early models came with a 5 speed manual and a 2 rotor engine. Once they dropped the 3 Rotor in I am 90% sure they did not offer it with a Manual transmission I have no idea why I just know Mazda did not offer it
I want to say the 20B Cosmo came out in 1991, I think it was a year or so before the FD or 3rd Gen RX7 came out, you could get the 2 rotor twin turbo or pay a bunch and get the 3 Rotor twin. It came stock with 300HP but with a few upgrades 500+ HP was very easy to get and you were not even pushing the engine hard. When you started to push like Dan is sort of doing with his 2 Rotor you started to hit the 800HP mark with them.
Every single 20B I have even seen imported from Japan was Auto, the first thing you had to do with them was pull the flywheel and put a Manual one on. That is not to say there were not Manual engines, maybe those cars were even rarer since it was a luxury car, but I have never heard of anyone getting a Manual Engine from Japan.
My dream has always been to drop a 500+HP 20B into a Factory Five Cobra, the sacrilege factor alone makes it worth it. Plus I think an 1800 lb FF5 chasis would be a blast with a low torque rotary in it. Less of a tire smoke machine and more fun to drive.
I assume guys are putting fd trannies on the 20b's when the do engine swaps?
But the cosmo came with the 20B from the factory.
I mean, if they're swapping it into an FD sure.
Dat 3 rotor goodness. Dat sound.
HNNNNG.
Wiki says the third gen Cosmo 1990-1996 only came with a four speed electronically controlled auto transmission. The car was marketed as a high performance luxury coupe - hence the auto.
also the most expensive car Mazda has tried to sell to date.......
3 rotors are mean sounding. But the ultimate is a 4 rotor pp port!
Someone do a 20b swap into a mini. And a 787 swap into... anything.
looking at the pre/post graph, i would be interested to know if they tuned for the meth before running it on the dyno. The meth increases octane, so more timing is in order, however if it is not tuned in, it just displaces oxygen and richens the mixture. Probably why there is a boost in torque in the mid-range but a loss at the time where lean power is preferred.
I have had nothing but good luck with meth (or green windshield washer fluid) The water reduced temp and meth increased octane, but tune too aggressively and you better have some sort of method of determining if your reservoir is empty. I have always preferred the windshield washer reservoir, especially if it has a low level switch.
Edit:
I just realized that the statement was pre or post turbo installation. disregard the graphs and my statement would be to install post turbo.
Since the heat of vaporization won't happen at ambient temperature, I would think that spraying it pre turbo would not be as beneficial than post turbo where the air is compressed and can be cooled through heat transfer of the water without pulling heat from the turbine housing which would be the first hot thing in contact with the water. This would flash the water and reducing the effectiveness per lbs injected. I would also be concerned with shock cooling the turbine wheel.
I'll have to redial in my air/fuel as the meth richens the mixture. There is a low fluid sensor so you don't run out, go lean, and blow up. My understanding is pre injection will momentarily bog the turbo down, but increase efficiency to top performance on the top end. So you loose some spool initially. I'd probably do a twin setup where there's some pre injection and more post injection. Try to get best of both worlds.
I'll add that guys were doing full pre injection on smallish turbos (60-1) and making ridiculous horsepower just because the efficiency is increased dramatically. Like 100hp over what you normally see on the same turbo.