Baldy

Assuming I'm not going to be changing elevations, a carb can yeild more power than stock EFI on a stock motor, right?



Are there sites that compare the different carbs available for the rx-7?



To me, they seem quite economical, allow removal of a bunch of crap from the engine bay, and they can be tuned for different environments, unlike stock EFI, right? Or am I disillusioned on the benefits of going with a carb?



I'm in my "information-gathering" stage at the moment. After I saw how cheap some of them were, I just had to ask more about them.

Tom93R1

I would say you are disillusioned by the benefits of a carb. The only benefit is you may be able to get a bit more airflow and a couple more HP out of it.

EFI will adjust for all sorts of changes like weather and altitude. To maintain peak performance in the carb it would have to be tuned constantly as the weather changes, EFI does this automatically. On top of that you dont need a choke with EFI, there is definately something to be said for that. What are your plans for the car? The EFI would definately be nicer if it is your daily driving car.

pengaru

I think you'd be better off with a SAFC on the stock EFI if you're looking to get bang for buck and good results.



Elevation is not the only variable you need to be concerned with, temperatures play a huge role also. I was at Grattan watching some formula mazda race cars run, and they ran like **** for the first set of runs early in the day. Second set of races they ran beautifully, the carbs were not touched. What changed? Ambient temperatures, the sun was high in the sky and we went from wearing hoodies to tshirts, and the cars noticed too.



Even the RC helicopter we were playing with last night was being a pain with the carb, we ran it in the garage where it was warm had it all tuned and running quite well... then we go outside to actually get it off the ground, start her up and just kept on dying @ idle. Just seconds ago it was idling beautifully indoors. It was around 2AM, cold night air.



I'd rather push some buttons on a laptop or other piggy back fuel controller, or even some ghetto rigged potentiometers to tune an EFI system than rejet carbs and deal with all the shortcomings that come with the lack of a microprocessor and sensors to deal with the very dynamic environment our cars operate in.



Carbs are static, they will operate with the paramaters you set when you last tuned them. So when you happen to drive in an environment just like the one you were in when you tuned it, you will have a happy car. Every other situation (the other 90% of the year? maybe more?) it will be off without adjustment.



EFI is dynamic, just like the world around you. Though it may not be perfect, it's certainly better.



These are just my opinions, I hope this doesnt turn into a EFI vs. Carburetion war

Baldy

ok, that's exactly the kind of stuff I was looking for. Just some stuff I was reading made carbs sound better, though I've had bad experiences with carbs on motorcycles. Thanks for the input! That's just one less thing for me to worry about in the future.

MPM

Instead of getting rid of the factory FI I would recommend changing it first especially if this is your daily driver. An stand alone EMS would let you eliminate the factory AFM(biggest bottle neck in the factory setup). I've seen dyno runs using a fuel only computer on a stock 13B 6-port engine that put 146HP to the rear tires. This car was still using the distributor from the previous carb setup.