DIY turbo on a 12a
05-01-14, 11:59 AM
#26
Oh I forgot to mention I'm talking about two turbo setups. One is done and running perfectly. The other is getting pieced together now. It's got the beehive and the deleted thermostat with the bypass hole blocked. It's in a baja so cooling back there is important. The other option is to forget the baja and throw it (the turbo) in another FB. Going back and forth on this one due to concerns that the 3 rib bus trans is almost too weak for an NA rotary let alone a turbo, but things like the fuel system were completed just the other day so it's one more thing checked off the list. The nice thing about the mallory fpr is it's compatible with NA and boost. I also used EFI hose (as should you where applicable) because it doesn't go bad (crack, leak) unlike carb rated hose which starts to get hard as soon as it has gas go through it for the first time. Still have to make some carb hats too.
Speaking of which, Robert at rotary shack is on ebay these days and sells aluminum fabbed carb hats for the Nikki with a 2.5" inlet. It's certainly an option for us, and I'd think with ebay's buyer protection, if he doesn't ship, you get your money back. Probably a pretty safe bet to buy through ebay. I'd consider it myself but figured out a way to use a stock blue air cleaner base seal and a 4" round tube to make my own hats out of steel. The first one I made worked fine. 1/4" top and a 2" inlet as 2.5" is kinda big, and it turned out really tall (pretty much wants to hit the hood but just enough gap that it doesn't). My next ones might try for 2.5" and be a bit shorter. We'll see.
Man it took me a long time to get into turbos but I'm glad I finally did. Once you drive a turbo, a good well set up one, anything else is just slow and lame.
Speaking of which, Robert at rotary shack is on ebay these days and sells aluminum fabbed carb hats for the Nikki with a 2.5" inlet. It's certainly an option for us, and I'd think with ebay's buyer protection, if he doesn't ship, you get your money back. Probably a pretty safe bet to buy through ebay. I'd consider it myself but figured out a way to use a stock blue air cleaner base seal and a 4" round tube to make my own hats out of steel. The first one I made worked fine. 1/4" top and a 2" inlet as 2.5" is kinda big, and it turned out really tall (pretty much wants to hit the hood but just enough gap that it doesn't). My next ones might try for 2.5" and be a bit shorter. We'll see.
Man it took me a long time to get into turbos but I'm glad I finally did. Once you drive a turbo, a good well set up one, anything else is just slow and lame.
05-01-14, 08:17 PM
#28
Anti piston
Thread Starter
Ok that's a lot of information Jeff thanks I will go trough it all before I continue. I am in the middle of restoring a 1972 dodge charger for a customer, so my time is being eaton up in that project but once I get that in primer I will be getting back to my rotary projects. I did make a cap for my carb also. I will get a picture of it up for you to see. Made mine out if steal but I also used a 12a rotor to make the shape templates from cardboard and then cut out the steal. Let me know what you think of it...
05-02-14, 12:35 AM
#29
Originally Posted by diabolical1
wow, Jeff, i guess i've been away longer than i thought. i like this though. 
I'm convinced the Nikki can do practically anything now. No need to get V8 carbs or italian racing carbs anymore.
The secret, which is not even a secret, is to make the venturis bigger than stock and do other air/fuel mods (all covered here and there on the forum). The resulting carb is able to handle boost or NA equally well. Seriously. That's one of the points mentioned earlier about how you don't really need to swap in bigger jets unless your wideband tells you to, and then only if you increase the air coming in with the usual mods (bigger venturis, booster supports trimmed and airfoil mod, removed choke flapper, and maybe thinned throttle shafts but I don't do that mod as it's not necessary unless you're looking for extreme max flow).I can literally take one of my boost prepped Nikkis and run it equally well on an NA setup and then swap it onto a boosted setup. Or use the carb in NA mode to break in a fresh rebuild, then after a few miles, swap in a turbo and a carb hat and not have to change anything in the carb, unless the wideband tells me to. Such convenience.
05-02-14, 12:43 AM
#30
Originally Posted by Dave.Martin2008
eaton
Would a charge pipe fit the inlet? If so, maybe you can use it as your carb hat. Does it have a seal against the top of the carb? It needs to seal well there. Maybe cut a slit in a piece of vacuum hose and wrap it around the lip. Superglue the two ends where they butt up. It could work.
05-02-14, 05:45 AM
#31
anyone hear need a turbo carb hat set for a nikki? also fits holley's iirc. not really trying to sell but im not using it and figured if anyone would be interested they would be in this thread!
if not sorry for going off topic, i was planning on going turbo myself but on US spec 12a's if you push more than 5psi you'll blow the seals out and destroy the engine, just went the porting route. Best of luck with your project!
if not sorry for going off topic, i was planning on going turbo myself but on US spec 12a's if you push more than 5psi you'll blow the seals out and destroy the engine, just went the porting route. Best of luck with your project!
05-02-14, 06:46 AM
#32
Anti piston
Thread Starter
anyone hear need a turbo carb hat set for a nikki? also fits holley's iirc. not really trying to sell but im not using it and figured if anyone would be interested they would be in this thread! if not sorry for going off topic, i was planning on going turbo myself but on US spec 12a's if you push more than 5psi you'll blow the seals out and destroy the engine, just went the porting route. Best of luck with your project!
05-02-14, 09:17 AM
#33
carb whisperer
Its just like anything else, though. How its built is critical. Safe boost, good fuel, good timing etc.
05-02-14, 12:45 PM
#34
Originally Posted by Sh00bs
on US spec 12a's if you push more than 5psi you'll blow the seals out and destroy the engine
I didn't let an artificial road block derail me. I'm running stock wastegate pressure of around 7psi on an engine that has 9.4 compression just like a US-spec 12A, and I've got 2mm apex seals which are supposedly easier to break and "destroy the engine", and they're longer, being a 13B and all, which makes them even more likely to break... but they didn't. Oh yeah, the exhaust port is wider too, letting the seal bow out a bit more, and they didn't "blow out" and "destroy the engine". Hmm...
05-02-14, 02:41 PM
#35
Anti piston
Thread Starter
Ok, then. I didn't let an artificial road block derail me. I'm running stock wastegate pressure of around 7psi on an engine that has 9.4 compression just like a US-spec 12A, and I've got 2mm apex seals which are supposedly easier to break and "destroy the engine", and they're longer, being a 13B and all, which makes them even more likely to break... but they didn't. Oh yeah, the exhaust port is wider too, letting the seal bow out a bit more, and they didn't "blow out" and "destroy the engine". Hmm...
05-03-14, 01:35 PM
#36
i'll be brief since this is neither the time nor the place to speak with great detail. suffice it to say, yes, do plan to have a turbo rotary project at some point, but right now i have more engines than cars. i'm juggling a whole lot of things at the moment so there's no real rush on it. i have 80% of a pretty pristine REW block and i buy parts when i can, so things are cooking ... just slowly.
05-03-14, 02:51 PM
#37
I too have more engines than cars. I have an FD shortblock, dissassembled and ready for whatever I want to do to it. But I really like the current R5 13B with the S5 turbo on it. My biggest concern is whether to throw the other S5 turbo in the rotary baja because it has a 3 rib bus trans which are not known for lots of strength. I'd rather not break it with a turbo, you know? But doing a turbo on it is child's play compared with the REPU which needs some kind of power adder, and the Camden is in another vehicle, plus it's not nearly as good of a power adder as the basic simple S5 turbo. The engine bay is very narrow and very short. It also already has a full long primary that actually does enhance low end grunt, which this sorely needed.
I'm thinking if I had not already invested so much time/effort in the REPU and was just starting out with my current list of available parts (Camden, S5 turbo, other) I'd have an easier time deciding to throw the turbo in it, but as it sits, the Camden literally bolts in, in a few minutes (or more like an hour but you get my point). The turbo, on the other hand, would take days and weeks of careful planning, custom tubular exhaust manifold, carb hat fabrication (not gonna buy the rotaryshack one for this) and a complete fuel system redo. Heck I just finished a complete fuel system install in the baja and that was no picnic either. But the baja is done and 100% compatible with a blow through turbo (MSD pump, mallory fpr, 5/16" send and proper 3/8" return all in EFI rated hose as mentioned before). I even have a boost prepped Nikki ready for it. Just need a carb hat is all. But the beautiful part is I can run it NA with a dead gutted turbo housing and an RB spun aluminum air filter assembly for engine break in which I suppose does technically free up the turbo for the REPU. The REPU can't use the stock S5 exhaust manifold due to its narrow frame rails but all that stuff fits perfectly in the baja. Decisions, decisions...
I'm thinking if I had not already invested so much time/effort in the REPU and was just starting out with my current list of available parts (Camden, S5 turbo, other) I'd have an easier time deciding to throw the turbo in it, but as it sits, the Camden literally bolts in, in a few minutes (or more like an hour but you get my point). The turbo, on the other hand, would take days and weeks of careful planning, custom tubular exhaust manifold, carb hat fabrication (not gonna buy the rotaryshack one for this) and a complete fuel system redo. Heck I just finished a complete fuel system install in the baja and that was no picnic either. But the baja is done and 100% compatible with a blow through turbo (MSD pump, mallory fpr, 5/16" send and proper 3/8" return all in EFI rated hose as mentioned before). I even have a boost prepped Nikki ready for it. Just need a carb hat is all. But the beautiful part is I can run it NA with a dead gutted turbo housing and an RB spun aluminum air filter assembly for engine break in which I suppose does technically free up the turbo for the REPU. The REPU can't use the stock S5 exhaust manifold due to its narrow frame rails but all that stuff fits perfectly in the baja. Decisions, decisions...
05-09-14, 09:07 AM
#38
Anti piston
Thread Starter
So I just secured $1,000 in a restoration job. Wife is getting some but how about you guys help me spend the rest on my car. LoL. I should probably spend it in a turbo setup. Any ideas as to what I should purchase to get going. Possibly a kit out there?
05-09-14, 11:24 AM
#39
Senior Member
Good luck finding a kit, im about to go turbo on my fb and am going to have to buy the parts myself and put it all together, I would like to go fuel injected but costs too much for my budget so im going carburated and im a welder so I will be making some of the parts myself
05-09-14, 08:22 PM
#41
Senior Member
05-14-14, 10:05 AM
#42
Anti piston
Thread Starter
So I am thinking of going with a 13b turbo manifold. Stainless steel. What size wastegate should I be looking at. Seams to me that everyone is talking about using a 44mm wastegate. But I have no idea as to what this does besides bypassing the turbo to control it. Is that all this part does in the turbo system. And then the blow off valve relieves the pressure on the intake side correct. Sorry for all the questions but I just want to get this right the first time. This will be a lot of money I am dropping into my engine.
08-03-14, 12:16 AM
#43
Lolicon*** of RX-7 World
I hope I don't get in trouble for this if this thread is already to dead? but if I may ask and put my 2 cents in but couldn't you use an old 83 saab 900 turbo's turbo charger.
I have one sitting around but it needs to be rebuilt with a new wastegate and exhaust side but I could give it up for like $50.
that's if this thread isn't so dead I get in trouble that is xD
If not then I could rebuild it and have a welder buddy of mine make me a manifold to fit the turbo I got.
its like a t13 turbo its very small but can produce quite the punch when I had my old saab running that is xD
can't remember how big the turbine was or how big the waste gate was but max boost on the turbo was maybe 20psi if you could tune it out right on the APC Box and get an Intercooler running.
but it ran stock on 8 psi think I could slap one of those on to it?
also I guess I should say its the same size as a T2 rx7's stock turbo but I would have to compare them side by side and not with just a picture but saab turbos were garret turbos back then and they were good and almost bullet proof unless you abused them I guess. but anyways if anyones interested in that look them up and try to compare them if you want. they look to be about the same. I just remember being told long ago its a T13 garret turbo and it was the biggest they offered at the time on saab cars stock.
I have one sitting around but it needs to be rebuilt with a new wastegate and exhaust side but I could give it up for like $50.
that's if this thread isn't so dead I get in trouble that is xD
If not then I could rebuild it and have a welder buddy of mine make me a manifold to fit the turbo I got.
its like a t13 turbo its very small but can produce quite the punch when I had my old saab running that is xD
can't remember how big the turbine was or how big the waste gate was but max boost on the turbo was maybe 20psi if you could tune it out right on the APC Box and get an Intercooler running.
but it ran stock on 8 psi think I could slap one of those on to it?
also I guess I should say its the same size as a T2 rx7's stock turbo but I would have to compare them side by side and not with just a picture but saab turbos were garret turbos back then and they were good and almost bullet proof unless you abused them I guess. but anyways if anyones interested in that look them up and try to compare them if you want. they look to be about the same. I just remember being told long ago its a T13 garret turbo and it was the biggest they offered at the time on saab cars stock.
08-12-14, 07:00 AM
#44
Anti piston
Thread Starter
It's not dead just slowed down. I just cleaned up a Mitsubishi turbo yesterday to try out on my engine. Going to the metal shop today to get flange plates cut so I can make a new manifold for this turbo to test. I will let you know how it does.
08-12-14, 11:43 AM
#45
Lolicon*** of RX-7 World
One thing it want to ask if you can make me one of those neat rotor carb attachments would be cool to have
08-13-14, 02:43 PM
#46
Anti piston
Thread Starter
I can but I need to destroy the ild blue one for the carb base. And I could make another one. Let me figure out what I have in one and time also. We can work something out. PM me and we will talk about it more.
08-13-14, 04:52 PM
#47
Lolicon*** of RX-7 World
and if anything dave I have been planning the same thing but need to get me a winter car first so I can tear this 83 mazda down now. been hoping one would show up for some time now though so I can get my hands on a 2nd first gen and just build one up for boost or a bridge port and then get it driving again then just rebuild the other motor for the normal everyday driving on a nice streetport and some exhaust.
but first gens are not just popping up like i'm hoping xD
