Hello Everybody,

I have been working on my RX-7 for a couple years now. Doing things here and there. From the beginning I wanted to do a carburetor blow through setup. I settled on the Nikki and started working on the supporting mods. Its been a couple months since the turbo has gone on and its been working great. I would like to thank the forum members for there posts and how-to's, especially Jeff20B for all his Nikki information. It would of been hard to know where to start without that info.
Now to the specs

1983 RX-7 S (Base Model) 95,000ish miles

Engine and Turbo:
Stock 12a Engine (Yes, an un-rebuilt stockport)
1979 12a Intake Manifold
Modified Nikki with 22mm Primary Venturi's, prepped for blow through.
CXRacing Radiator.
Proform 67015 Electric Fan designed for a 1987-1993 Ford Mustang
CXRacing Oil Cooler (Mounted up front)
Mishimoto Oil Thermostat
Borg Warner S200sx-46 making 10 PSI
Tial MV-R Wastgate
2.5" Cold Side Piping
Ebay BOV
EMUSA Same Side Intercooler
3" Downpipe and Exhaust
Racing Beat Universal 3" Pre-Silencer and Muffler

Gauges:
Glowshift Wideband 10 Color
Glowshift 20 PSI Boost 10 Color
Summit Racing Fuel Pressue Gauge (Under Hood)

Ignition:
NGK B9EG spark plugs
Direct Fire Ignition using GM Ignitors
TFI Coils on ugly custom bracket
(Yeah, the wiring here is not good. But it hasn't given me any problems since I installed it over a year ago.)

Fuel:
MSD 29387 Fuel Pressure Regulator
MSD 2225 Fuel Pump

Suspension:
Racing Beat Springs
Racing Beat Front and Reat Sway Bar
Energy Suspension Control Arm and Tension Rod Bushings
Kosei K1's wrapped in 205/50/15 Nitto Neo-Gens

Don't have any numbers for HP or 0-60 or 1/4 mile times. If I ever do, i will post them.

 

Nice!

 

Hello,,,
nice work.... Can You tell me where You got that carb hat? OR did You have to make it Urself?

Thanks,
Sam

 

A friend made it for me. I happened to mention I was going to need a carb hat. And one dayday w I got home from work he had made one for me. It has a 2.5" inlet and the base is close to 4". I use a large o-ring to seal it.

 

Cool!

 

 

What transmission/rear end are you using?

Hehe looks like under my hood. Cool.

 

Another blow through Nikki!! Woo Hoo!!

 

Stock 83 transmission and stock 83 open diff with drums.

I have a spare 84/85 transmission and a 84/85 lsd rear end. I just have to clean up the diff, get emergency brake cables, and figure out the brake lines for it.

 

How much advance are you running on your distributer? I cut it down to about 6 or 7 degrees, and the car seems happy.

Why 22mm primaries? Is the 12a not that hungry? More torque?

I like the coolant over flow location... that's what I need to do to mine. I just kinda lazily shoved it on top of the charge piping with the idea of "I'll get to it latter"

I thought you would say turbo ii trans. Have you worn out your clutch yet? LOL it'll happen soon enough. hehe. I am trying out the ACT 6 puck clutch next. The 3 puck Exedy clutch is starting to give way after about 12k. I do kind of beat my car though.

 

I can assure you the 12A is quite hungry. I've got 24.8mm on mine and will try a bigger size next. The engine has a total of 8 miles on it (yes, I said eight) and I've already boosted it. The secondaries are transcendent. Hence the desire to up-size the primaries. Oh and smaller primaries do not equal more torque. People need to get that out of their head. Bigger = More Flow = More Torque.

Speaking of the clutch, it still smells a little like it's breaking in, because it is, but it consists of a new RB light steel flywheel, new Exedy standard duty disc, and RB street/strip p-plate. Enough grip and perfect effort. I tested an Exedy stage 1 and didn't like how stiff it was. Likewise tried a new Exedy standard duty which came with the disc, and hated how soft it was with the friction point at the very top of the travel, leaving all this extra useless travel. The RB SS p-plate is perfect so far.

 

I am currently running about 12 degrees timing on the locked distributor. I accidentally ran 20-25 degrees of boost because I read the timing marks wrong. That was when I was running about 7 psi of boost. It didn't have any ill effects. It started fine, idled fine. Didn't ping or knock. But I brought it back down to a resonable level.

I chose to make 22mm venturis because it was my first time modifying them. I didn't want to overdue it and lose the shape.

I used the mounting spots for the sub zero tank to mount the coolant overflow tank.

I did replace the stock clutch before I turboed it. It was about a year ago. The stock pilot bearing seized up causing the input shaft to keep spinning with the clutch disengaged. I put in a SPEC stage 2. It has been doing good. Not to heavy and not touchy. The stock transmission is a little slow to shift. It may be just the transmission or maybe the syncros. I don't have another to compare it to in the car.

 

I may try modifying another Nikki with bigger primaries. But my 12a is still a Stockport. It isn't flowing much air at the moment.

 

I just tried a 25.55mm Nikki today and the engine is still hungry for more. I wonder how much bigger I can go...

 

Awesome set up. Just beautiful.

 

I want to do this for mine! Your is great

 

I was wondering where I got that carb hat from ?

 

Post #4 mentioned that a friend made it for him.

​Sort of glad you bumped this thread though. Now I'm reconsidering my Nikki's 24mm primaries... we'll see...

 

Jeff seems you the man for running Nikki Carb blow thru. please PM

 

Id be so keen to know what the ins and outs are to do this to a 12a Bridgeport... or even if it’s possible... Jeff20b are you able to shed some knowledge on this? Have modified severl nikkis to run in na but now want to go down the rd of attempting to turbo 1...

 

Jeff20b hogged out my Nikki carb a little over four years ago and I’ve been super happy with it. I only have bolt on mods and I couldn’t be happier with his work. Would completely recommend his work 👌🏼

 

Jeff build one like 7 months ago with a mod dizzy as well. Im very pleased with his work.🔥

 

very clean set up man 🔥