tweeder06

Hey guys im new to the forum and kind of new to the RX7's. I was curious on what kind of streetable power the 12a can make. Ive looked through the dyno and engine building sections but havent seen what mods really create power in these motors. Also how much power makes this a fun little dd?

sen2two

if you dont mind loud car. get a holley 600, Racing beat intake manifold, good headers, and a bridgeport.



if you want it more quiet...a street port, or even no porting will be good enough. just do the above mods minus the porting.



if you want to go wild, a Peripherial port on the street cars has been done.



if your not sure what these ports are. do a search on here. its all there...

tweeder06

Well i looked into the porting and was deciding between an agressive street or a bridge port. I want to add a new carb, a ported intake manifold, ported headers and exhuast along with a msd ingnition with a fc radiator. I would really like to put 200hp down on the pavement but looking to be streetable. Are those numbers achievable with that kind of set up or am i just dreaming? I appreciate the info.

zeroecco

All those are possible and get some serious numbers on a first gen (remember the chassis is less then 2600 lb) but another why to go and I think the more reliable and fun way is a low boost turbo or a supercharger. you will see the same or better numbers and the added benefit of a smoother dd. REMEMBER these little cars made 100 bhp origonal power, so if your going to tack on another 75 to 100 bhp you really need to think about the suspension and the brakes because the car wasn't made for that extra stress and it will show with the extra "go" factor. But to answer the question directly



a light weight flywheel~300.00-600.00

header~250.00

upgraded emissions (modern high flow catalytic converter w/ smog pump)~ 300.00

a weber dcoe, ida 48(which I have), or a holley 600 (will need fuel pump)~700.00

short shifter~200.00



total is approx. $2,000.00



That will give you alot of "go" about ~ 130 rwhp which is around 150~160 bhp



Another thing you can do and I heavily suggest is trying to find way to drop some serious pounds on the car. if you can get it down to 2100 lb you would find that those 150 horses will put a real smile on your face.

RE_TurboFB

I agree the lighter the car is, the faster it is. It will corner better and have quicker stopping distance also..



I also like the low boost turbo idea ( like 5-6 psi ) I think the turbo will make better numbers. plus I think you will "feel" the power of the car cuz of the torque from the turbo..



You can find a stock FC turbo for like $50-$100. A basic rebuild kit is like $50 for it.

You have to make a 12A turbo manifold but thats prolly the hardest part..



you can turbo a 12A for cheaper then most people think... Just look at the stock turbo setup one the Nissan turbo 300ZX (Z31)

It has no intercooler or blowoff valve.. Not saying I would run it that way, But thats the way they came stock and it worked....

sen2two

turbo does always seem to be the best route.



but tuning with a carb and boost can be tricky. and converting it to fuel injection just isnt worth it. much easier to drop in a 13b. a stock S5 (89-91) NA with a holley or some webers, will feel great in a 1st gen. especially if you drop some weight!



but if you want to stay with a 12a, and be streetable. maybe some nitrous is in order. a 75-100 wet shot would feel great! and you dont ware on the motor unless your spraying it. thats a good daily driver feel until you open that bottle.

RE_TurboFB

True that! Nitrous is by far the biggest bang for your buck, and it keeps it as streetable as it's going to get...



what are the chances of detanation when running enough nitrous to get 75-80 HP..????

sen2two

not sure...but either going to run a 50-100 shot on my stock un-rebuilt 12a. we'll see how it goes.



just make sure its a wet shot. im going to tap the priamary, or the secondary runners (not sure wich yet) on my RB manifold. so its a direct port injection. i think it will hold up nicely. just be sure to retard the timing a bit. it would be better to have an MSD 6btm. but im going cheap and will just turn the dizt. back a little....lol

j9fd3s

a stock block 12a flows enough to do about 150hp flywheel

a "street port" will do up to about 180-200 depending on the size and quality of the porting

a bridge is capable of 250ish, but its really dependant on the size and shape of the bridge



if you wanna do about 200hp down, you're looking at a really dialed in street port, or a mid sized bridge.



my numbers are old, its prolly possible to beat em nowadays, people are running larger exhausts, you can get efi, bigger than 51mm etc etc

tweeder06

Thx for all the info. As i do want to stay 12a and carbed. What would be one of the better carbs to supply alot of power and torgue through out the power curve? My next project after this will be boosted. As for the suspension i want to swap the entire rear end to a gsl-se, put tokico blues and possibley rb springs. As for the brakes i would like to do stainless steel lines with hawk pads and better brake fluid. The nitrous would be great but im looking more for an autocross car. I will be living in indiana when this gets done so i wont have to worry about the emissions. What is a good wheel and tire size? I was looking for 15/7-15/7.5 work emotions.