View Full Version : 10A Rotary Turbo?
Okay peoples, let's talk about a very scary subject, just for legalities sake.
10A Rotary Turbo!
Been done before? I don't think so.
Budget:
Bare minimum
The merchandise:
Stock 10A motor
Worn out 12A Turbo components (including block if possible, yet to be purchased)
Obvious tasks:
Cut and shut of std 12A turbo manifolds to suit 10A
Obvious Problems:
Because the 10A uses carbon seals it cannot run more than 8PSI of boost.
Using custom steel seals will destroy 10A rotor housings (which are hard enough to come by)
So, 8PSI boost it is. Is this really worth the effort? I mean it's cheaper to find an engineer that will weigh your car accidently heavier so you can squeeze a 12A into it right?
Isn't a 12AT legal in an 808 - the 1600 808s were 960kgs... 960x2.5=1920+450+30=2400ccs..
Bugger cutting and shutting manifolds - the exhaust would have to be custom made to put the 12AT into the 808 anyway. the 12AT throttle body should be (easily) made to fit onto the 10A 4bbl manifold, althouh you'd have to port the crap out of it (still can't find a Weber manifold?).
Where did you get the 8psi figure from? I've never heard anyone give a (any!) figure on what the 6mm carbons could cope with. I looked very hard at building a 12A twin dizzy turbo some time back, but there's an easy solution for them - single dizzy rotors.
Sure 1600 808's are 960kgs, but do you think I could get my hands on one?
Buh-bow......I was this close to scoring one 6 months back, until the guy took it back at the last minute and gave it to a 17yo punk who knew jack about cars, especially 808's. He dodgeyed it through rego and has abused the body like nothing else since then.
My 808 has a factory weight of 810kg (according to rego and manufacturing data from Mazda) Find me an engineer that will legitamately say my car weights more with my upgraded parts (diff housing, new brakes, etc etc.) and I'll do the 12A turbo.
I know what you're saying the manifolds are a shit of a job, no way in hell would anyone think of handing it to someone to do (especially for something this warped out) it would be a full backyard job (or under the table transaction)
8psi figure? Well I've been talking to a couple of rotor shops about this kind of project, and it's always met with a raised eyebrow and nods of the head. I called Redline rotary and he said no way would the 10A stand up to boost because of the carbo seals. I talked to Mazperformance (now dissapeared off the planet) and mentioned the idea to him and he liked the idea, especially set up with the right manifold to let it flow properly to 10,000rpm. But he was the one who said to me "You can't give it more than 8PSI of boost, otherwise you'll blow an apex seal instantly"
What's the point of building a 12A twin dizzy turbo and using single dizzy rotors? Isn't that just exactly the same as the standard 12A Turbo? You'd be running the steel seals and you might as well change the rear end plate to suit the later model bell housings. It would just be all weird running twin dizzies with fuel injection wouldn't it?
One thing while I've got you, you mentioned the flow of the original rotor inlet manifolds being quite poor, so how does this help the modded Stuber 12A carb?
Firstly, the 10A turbo idea sounds cool, but is probably not worth the time, effort and money to do it.
As for the carbon seals, I don't know whether the boost, the extra heat or the increased chance of detonation would be the determining factor, but I wouldn't even contemplate building a turbo engine with carbons.
With the mighty 12A Twin Dizzy, single dizzy rotors actualy give the engine some bottom end torque and hp due to better design and tighter sealing.
A mate of mine has one and it goes very very well with none of the typical Twin Dizzy "I think I can I think I can I think I can" when trying to start it.
You can use a single dizzy front cover and use an RX-7 electronic dizzy (Spac's mate bought an RX-2 of me with this done to it) or go crazy and use a crank angle and injection (or maybe two crank angles just for spin value).
You also cannot just swap the rear housing from a single to a twin dizzy as they are not the same and will not fit. So if you want to keep your twin dizzy box, and indeed original engine number, the best thing is to rebuild the Twin Dizzy with single dizzy internals and front cover and electronic ignition.
I haven't paid much attention to NSW engineering requirments lately, but if used to be that they took the weight of the vehicle to be the heaviest engined, base model of that body shape.
So the weight for ALL 808 sedans should be that of a 4-speed 1600 sedan - 960kgs. Ring a couple of engineers, and see what they reckon.
Originally posted by Dazz
A mate of mine has one and it goes very very well with none of the typical Twin Dizzy "I think I can I think I can I think I can" when trying to start it. [B]
Hmmm...i don't like the sound of that! I hope my twin dizzy isn't too much of a bastard to start!!!
[B]You also cannot just swap the rear housing from a single to a twin dizzy as they are not the same and will not fit. So if you want to keep your twin dizzy box, and indeed original engine number, the best thing is to rebuild the Twin Dizzy with single dizzy internals and front cover and electronic ignition.
So you can't rebuild a twin dizzy with later 12A end and centre plates??? I was under the impression that you could rebuild a single dizzy 12A using twin dizzy housings (because of their low wear factor). If i wanted to rebuild my twin dizzy can i change the rear end plate for a later one to allow the use of a variety of gearboxes? I'm confused! :( I was considering the following rebuild of my twin dizz: single dizzy conversion, extend ported, single dizzy rotors, single dizzy plates (??????) and also have the twin dizzy exhaust ports opened up. Does this sound feasible?
Cheers,
Bill.
PS sorry about the thread hijack Jon, go a 10A PP!!!:D hehe:)
Twin Dizzy rotor housings and end plates are not interchangable with single dizzy rotor housings and end plates.
The best you can do with a twin dizzy is install single dizzy rotors, gears and front cover.
The only gearbox that will go behind a Twin Dizzy is a Twin Dizzy box, or you need a super rare RX-4 Twin Dizzy bell housing which you can then put an RX-4 or RX-5 'box behind, basically.
If a twin dizzy is old or has not been clearanced properly when rebuilt they can be hard to start when hot.
Originally posted by Dazz
[B]The only gearbox that will go behind a Twin Dizzy is a Twin Dizzy box, or you need a super rare RX-4 Twin Dizzy bell housing which you can then put an RX-4 or RX-5 'box behind, basically.
/B]
I actually have one of these super rare rx4 bellhousings!!! :) I'm not sure if i will rebuild the twin dizzy yet, i might get a single dizzy 12A or possibly a 13B.
Wouldn't bother with a single dizzy 12A if you have a twin dzzy in the car already - like Dazz hinted, there are several other things to change, and a twin dizzy motor with single dizzy rotors will go about as hard as a single dizzy would. And cost you less.
Rota_Motor
03-09-02, 01:25 AM
Originally posted by Dazz
The only gearbox that will go behind a Twin Dizzy is a Twin Dizzy box, or you need a super rare RX-4 Twin Dizzy bell housing which you can then put an RX-4 or RX-5 'box behind, basically.
[/B]
goddamn, mr808 and myself must be a rare breed to have these superhard bellhousings, especially as I picked mine up for $20 along with all the parts I could carry (all you could carry sale ), and I also know where theres an RX-4 T/D motor and gearbox, just waiting for me to get it running ;)
twins everywhere, anyway, as for the 10A Turbs, that would be pretty good I reckon, not really worth the money for the power, but nice none the less.
ummm whwere the hell do you find 10A's any more? I want one.
Spac had one of these bellhousings, then he gave it to me. Now I'm running a 12A flywheel and clutch with a 121 5 speed gearbox behind a 10A! It's definately something that makes rotor fans scratch their heads.
I find people popping up all the time with 10A's and their gearboxes stashed under a workshop bench trying to get rid of them for around $200-$400.
For what it's worth, I don't think they have the power, but then again, I could have set mine up wrong. I don't have the time or the money to work it out anymore. I think I'll just bum a ride off someone with a 12A and see what I reckon then.
I tell you what, a lot of people are really keen on 10A's, probably because they're cute and rev to 10,000! (Can't say I can get mine that high, probably detonate before then)
Rota_Motor
03-09-02, 09:21 PM
hmm, I thought I was a 12A fan, but now I want a 10A, just to be really different.
thats why I started out with a 12A, no-one wanted to use them if they had them, always wanted a 13B, but now I know a few 12A diehards ;)
Actually a while back somone wanted to sell me a 10A BP, 48 ida and 4 speed. He wanted $800 for it but he was a total wanker so i didn't buy it! :rolleyes: I want a 13B turbo (just to be different!!! :)) after my injected 12A extend port! :D
What I would've given for a 10A BP! Far out, that would get some heads spinning!
I'm finding the fuel savings on the smaller motor are so marginal, that if you decided to do a 10A, instead of a 12A, to save money on fuel, you'd regret it.
I ran out of fuel this morning, cause I tried to get more than 350km to a 65L tank....oh well.
Originally posted by Jon
I ran out of fuel this morning, cause I tried to get more than 350km to a 65L tank....oh well.
I take that's fanging it a fair bit, not just cruising?
Are you sure you don't have the 45 litre 808 fuel tank and not the 65 litre rx3 one? That's a thirsty little bloody 10A!!!!
Ask Spac, he gave me the 65L tank, it's even got the big "L" on the back for the "Large" tank.
And yes, it is thirsty, a lot more than I calculated actually.
I've driven a STD 13B that does about the same, so I can't see any benifit of having the 10A other than the WOW factor. Maybe a more restrictive straight through exhaust might help.
Maybe the main problem is, it doesn't have enough grunt to just drive around on part throttle, to accelerate a little bit more quickly, I have to tap into the secondaries to get it going anywhere.
Oh well, that's the bad part about rotas, the economy. I wouldn't mind getting my hands on an rx3 tank though, how much do they usually sell for?
'bout $100 to $150.....I'd even look into getting a custom 120L tank built so you can get further without filling it up!
At the moment, with the rotor, I'm getting as far on one tank of fuel, with the bigger tank, driving sedately, as I was thrashing my piston motor all day every day.
You know you get 3 times as much torque out of a 4AGZE than you do a 12A Turbo for the same horsepower figures? But I wont start that argument.
Due to my lack of finances (and getting whipped) I'm almost about to defect back to piston motors.....chicks just don't get it.
You still got that piston motor I gave you Spac?
*smacks Jon over the head with an eccentric shaft* how dare you suggest such a thing as returning to the dark side!!!!:eek: Get yourself a nice injected 12A extend/mild port and then see how you feel about rotors! It will hammer, be reliable, pretty economical and be great fun!!! That's what i'm getting next!!!!! Or alternatively you can by my twin dizzy......;) :p Actually i'm considering a foray into the darkside. A mate said he would sell me his mint condition L24 skyline with its dead stock motor for about $400. I want to get the thing and chuck an RB20DET in it for some boostin action!!!!....or if i go totally insane, i could save up about $15k and chuck an animal 20B in it with a gigantic truck turbo pumping 40 pounds boost, ready to win horsepower heroes !!!! :eek:
*mr808 takes medication*:p
I'm affraid I've been converted.
Rego is due in two weeks and I have $1000 only. With insurance, new exhaust, oil cooler hose and all the other costs (possible engineers certificate!) I'm way over budget.
I've been given a Mazda 323 with a blown head gasket, it's rego runs out in one week. As far as I'm concerned, I'll fix the gasket myself (the dodgey way) put it back together, and drive that until I can save up the money to fix the 808.
Sorry guys, I'm just in no position to afford a rotor anymore.
*Bugle plays the death march in the back ground*
My 808 will retire to the backyard
*Bows his head and says a silent 'Mazda' prayer'
*mr808 continues smacking Jon with eccentric shaft until he can beat no more.....looks at Jons battered body...'whoops sorry Jon!" :) *
Okay Jon, pull the 808 off the road, drive the 323 for the rest of the year doing burnouts in it etc for fun while saving the $$$ for this 808 we're gonna build ya!!!;) We'll chuck my twin dizzy in it, maybe rebuild it first, get a few little goodies, maybe a weber and fix up the rest of the car! ...under no circumstances will you put pist-on motor back in the 808!!!!!! Oh yeah if you need any help tuning the 323 motor let me knoW! I coinsider myself an expert after tuning the 1.3 in my 808 to with in an inch of its life!!!:p
Thanks for the offer, I've actually built 3 1400 UC motors now, so I can change the head gasket with a shifter and a swiss army knife.
Don't worry, I'll post a thread later on my thoughts regarding an engine conversion for the 808 later. I'll have to talk to some other rotor owners to see the $$$ difference.
The offer's always there if you change your mind mate;)
What were we talking about in this thread again?
ummmmmmmmmmm.......i think it was something do with how to make japanese origami or was it how to make Grandma's traditional carrot cake????:rolleyes:
hehe :p
What ever it was, it tasted a bit stale. I think I've still got a bit stuck under my gum.....
Anyway, the trick is to use two eggs! Not just one! That gives it all the texture it needs, and it clings together during the baking process
*Jon grabs the monitor with both hands and head-butts it!*
BACK TO WORK!
I find a little bit of K&N filter cleaner really brings out the taste of it along with a splash of Fast Orange handcleaner! :p hehehehe!:p
*mr808 grabs own hair and slamshead under toilet seat numerous times then returns to happily browse PF* :p
I find a little bit of K&N filter cleaner really brings out the taste of it along with a splash of Fast Orange handcleaner! :p hehehehe!:p
*mr808 grabs own hair and slams head under toilet seat numerous times then returns to happily browse PF* :p
Sure 1600 808's are 960kgs, but do you think I could get my hands on one?
Just so that you know, you don't actually have to get one of the heavier models... the RTA (in QLD at least) will work off the weight of the base-spec sedan with the heaviest engine & driveline combination available from factory.
i wonder if that's the case in the ACT/NSW??? I hope so!
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