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supercharged or turbo my 12a

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Old Nov 22, 2009 | 07:41 PM
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supercharged or turbo my 12a

i need some help on wat i should do to my little 12a. at the moment its stock. my orignal plan is to supercharge and street port and a modded nikki it to get about 300whp. i have seen the 12a turboed. is it fairly easy or is it a pain in the ***. i am a mechanic so im up for the work. i would like to talk to people that have supercharged or turboed there 12a
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Old Nov 22, 2009 | 08:38 PM
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Originally Posted by Jmthegerm66
i need some help on wat i should do to my little 12a. at the moment its stock. my orignal plan is to supercharge and street port and a modded nikki it to get about 300whp. i have seen the 12a turboed. is it fairly easy or is it a pain in the ***. i am a mechanic so im up for the work. i would like to talk to people that have supercharged or turboed there 12a
You will never see over 170 rwhp out of a camden and streetport. Not that that is bad, they promote a 30% increase and do not mislead promising more, we just usually have much higher expectations. As for turbo, go searching....
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Old Nov 22, 2009 | 09:10 PM
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You are expecting waaay too much power man. Don't be discouraged though, even 150 at the wheels in these cars feels quite quick.
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Old Nov 22, 2009 | 11:43 PM
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Originally Posted by Jmthegerm66
i am a mechanic so im up for the work.
not downing you but if you have to ask how hard it is. it may be above your pay grade. the turn mechanic gets over used. your best bet is going to be but a turbo kit that has been run on a 12a. also make sure it comes with a carb. watch the for sale threads. also 300hp is a big goal for someone that has never messed with turbo b4.

SC is fun but the kits for that are a lil on the high price side for the HP they put out IMO.
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Old Nov 23, 2009 | 02:31 AM
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I know it will be hard only because of fuel management issues.I have seen 300whp out of a 12a and supercharger idk wat port it was. I'm just trying to c wats a better way to go
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Old Nov 23, 2009 | 10:53 AM
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Head over to the 1st gen forum and search "turbo 12A" and you will have hours of reading from those who have done this. I wouldn't recommend a supercharger for the reasons already stated.

A wicked combination with a street ported is a T3 based turbo such as the GT30R. Get the 1.06 turbine housing and then make a manifold.

Forced induction on carburetors sucks. Go with an inexpensive EFI setup such as a used standalone or a new Megasquirt.
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Old Nov 27, 2009 | 05:02 PM
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I have several of both species although I am not a tuning expert by any means I do have opinions that differ from those posted

Your choice of turbo or supercharger needs to really be based on what you plan on doing with the car.

If you are going to drag race the car by all means go turbo in the long run it will be cheaper and many others have done all the ground work for you. If you are going to autocross it, turbo is a good option, the power doesn't come on so low in the rpm band that it makes it uncontrollably tail happy. If you want a street car in a very simple form that is easy to maintain I recommend the supercharger. I won't push to much into detail just look up posts under my name with supercharger as the related tag you will find a few.

I am not going to claim 300 rwhp that is not realistic on a street setup, what you do need to look at is the s/c is much more fuel efficient which helps greatly on the street, much simpler to install and set-up it does produce alot of low end torque.

What most people fail to realize is the power differences between the 2 if you want high HP and torque but don't mind running at high Rpm all the time go trubo. great for pure racing applications and well developed. If you want a large HP increase and torque but want it in street useable RPM range (3500-8000) in a nicely streetable car go supercharger.

Don't get me wrong I won't give up my turbo cars but I will grab the keys for a supercharged one first.
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Old Nov 28, 2009 | 11:11 AM
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Well, turbos can be sized to produce any kind of powerband you want. Just because there are a load of single turbo setups out there with monster turbos mismatched to the engine, running on poor tunes and barely working, does not mean that any turbo rotary is laggy compared to a supercharger.

Has anyone ever posted some supercharger dyno graphs? I'd like to compare that to a stock TII dyno pull.
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Old Nov 28, 2009 | 04:58 PM
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Exclamation

Sorry if I'm wrong, but I'm a noob and am looking for clarification myself. From browsing this site the last few days it seems like the full b13t swap from an 86-88(using the ecu, tranny from the 13bt) is the most cost effective way to really up the hp from a 12a. Mod the 13bt and maybe get close to your goal?

Am I off base?
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Old Nov 29, 2009 | 10:02 AM
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No, you're not off base. In many cases that is the way to go as opposed to modding the 13B NA/12A.
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Old Nov 30, 2009 | 09:19 AM
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ive built my rx7

Originally Posted by 84stock
You will never see over 170 rwhp out of a camden and streetport. Not that that is bad, they promote a 30% increase and do not mislead promising more, we just usually have much higher expectations. As for turbo, go searching....
ive got a 85 rx7 with a fully built 12a streetported engine hooked to a 7 inch camdem supercharger with a holley 650 double pumper on her runnin 93 octane and im pushin 328hp and 273 torque. the whole reason i did it was bc people said it couldnt be done
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Old Dec 1, 2009 | 12:25 AM
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Pics please

Last edited by mar3; Dec 3, 2009 at 02:22 PM. Reason: Killd quote since reply was back-to-back to post in question...
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Old Dec 1, 2009 | 01:55 AM
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Originally Posted by jimbowatson2002
ive got a 85 rx7 with a fully built 12a streetported engine hooked to a 7 inch camdem supercharger with a holley 650 double pumper on her runnin 93 octane and im pushin 328hp and 273 torque. the whole reason i did it was bc people said it couldnt be done
I'm pretty sure the camden flat out cannot not flow that much, but feel free to post a dyno and prove me wrong.

As for the OP, I HIGHLY recommend turbo-ing on these engines. Rotaries put out immense exhaust energy and can spool some gratuitous size turbos compared to a comparable piston engine. That and they are too damn loud, which a turbo helps to quell. There's just too much going on with the exhaust for me to toss that out and recommend a S/C.

As for 300whp, that is EASY DAY on a turbo. With stock s4/s5 junk you can hit 250whp if you're spot on (I know, I drove one!). Go with a hybrid and you're there. kid's stuff compared to most on this forum.

I think blowthrough carbs is kind of neat, but a Stand-alone is the way to go.
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Old Dec 2, 2009 | 01:56 PM
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thanks everybody for the help. i think im going to use a tbi system with a turbo.
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Old Dec 3, 2009 | 12:01 PM
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ill post pics on here soon as i get back to the states, im kinda in the middle east right now but ill be sure to. that thing is my baby!!! hahahaha ....... oh and if anybody is from north WA ill be glad to get together if ya want.
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Old Dec 3, 2009 | 02:22 PM
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The actual DYNO sheet is what we all want to see...

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Old Dec 4, 2009 | 03:59 PM
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Originally Posted by Jmthegerm66
thanks everybody for the help. i think im going to use a tbi system with a turbo.
That sounds like a really good plan. What prompted you to go with tbi?
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Old Dec 7, 2009 | 10:38 PM
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if the tubo is too much trouble, you might try for a good carb and exhaust. I had a 1980 12a with a mikuni side draft and racing beat headers. this pretty much removed emissions (no thermal reactor) but it moved like a bat out of he!!
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Old Dec 8, 2009 | 02:34 PM
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Originally Posted by jimbowatson2002
ive got a 85 rx7 with a fully built 12a streetported engine hooked to a 7 inch camdem supercharger with a holley 650 double pumper on her runnin 93 octane and im pushin 328hp and 273 torque. the whole reason i did it was bc people said it couldnt be done
yea... no you're not. the camden simply can not move enough air to produce those numbers on the setup you described. but i'll wait for the dyno sheets...
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Old Apr 20, 2019 | 09:26 AM
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Hi
I am going ( i hope) tu buy my 1st rotary next week : it's a 1983 12 a. I was wondering if that project of building a turbo kit came into fruition....If anybody else know about kits i am interested.
Thanks
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