So here is the deal.. I already have a 87' TII, 91' Vert, 86' LT1/T-56 and just picked up a 1990 GTU.

The GTU was abused and all sorts of vac lines are plugged ports hardwired open and home made block off plates used on everything. The TPS is shot and the vac switch is dead..

All these mazda parts to keep everything working properly are a crap shoot on ebay and even the forums here as they are all used or NOS 20+ years old. Instead of spending almost 2k on just sensors and switches OMP etc to get the car running correctly again I'm thinking of going carb.

I know everyone says FI for better tune/gas mileage and more reliability of idle and so forth. I plan on doing a mild street port eventually and I know nothing of carbs on a rotary as my other cars are bone stock restored except the LT1 converted of course.

What is the best intake manifold for a 6-port NA and is side draft webers/mikuni/etc an easier go route like a lot of the BMW guys go w/ 2002's or do I go w/ the J-Tec (or w/e its called) or RB upper intake manifold and drop a holley on it?

 

You could install a Haltech Sprint RE and flying lead harness with brand new sensors for less money than a good carb setup.
Platinum Sprint RE ECU

However, if technology confuses you, then here are some links about carbs:
Rotary Tech Tips: Carburetor Applications
http://www.racingbeat.com/manuals/intakeguide.pdf

 

I'll check into this, thanks.

 

Only need this to delete the limp mode from OMP failure I do not see it useful and already contemplated an rtek 2.0 for disabling this option. Rtek being the cheaper option. My harness is fine its all the components on the engine that are removed/disabled I would need to get actuators for the 6-port etc etc.

Does this replace the TPS and vac switch? If not together those new are 800+ if you can find them and I have already been that route on the vert buying 2 garbage units. One from forum, other ebay. I then was able to purchase one from a company in Japan NOS.

 

By Vac switch you are talking about the map pressure sensor?With the haltech you can use any aftermarket sensor,use a gm map sensor.They are cheap and some vendors here in the forums offer them with pigtails for a decent price.On the tps you can get one cheap 2 and some guys here and on ebay offer a warranty on them.
For any other 6port hard parts use the forum or ebay.Sadly 6port people dont build 6 port stuff and most of the times they let go the parts cheap or free.I just scrapped a ton of sixport crap just 2 clean room on my garage.lol

 

Entry level EFI systems are around $300. Check out the MegaSquirt if you are willing to learn.

 

sorry for hijacking this thread but searched alot and i cant seem to find the answer im looking for. now ive read that people have done this,but what i want to know is can i use my stock efi ignition while running a holley carb sorry for u guys that dont like carbs but i find them very easy to tune and maintane. now i realize ill have to run premix while deleting the omp what i want to will the ecu still be able to advance the timing using just the cas since thats all im going to utilize along with the rest of the ignition system and my fuel pump is already wire to a switch po did a real number on this car so im going to just take it down to the basics with what i kno

 

You have to retain all of the stock sensors for the ECU to properly handle ignition when running a carb. Including the AFM.

 

ok but what about tps since i have an s5 na with an s4 uim i dont think its hooked up or atleast correctly