Well the engine is built and in the car, and other than an "Exxon Valdez" problem yesterday will spining it over to build oil pressure, we are going to fire it up tonight at about 6:30pm for those who wish to see "the big moment" lol

 

The amount of work that went into that must be incredible. Do you have a site or thread somewhere that shows your off the build in more detail?

Hope you bring this by Mosport in May so we can check it out!

BTW: Where did you get your braided SS lines and terminals from? Looking for a good supplier out here...

 

http://abrracing.com/

 

Thats why we put all the work into it is to race it at Mosport! lol. The May10th weekend is our 1st race weekend of the year, and we will be racing that weekend! (unless it rains)

 

What's the advantage of running a carburetor set up versus modern electronic fuel injection?

 

The honest answer is ....................Thousand and Thousand of $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

The carb set up costs about $1000.00usd. No one other than Mazda itself has had lots of success with EFI on a periperhal port engine that revs over 8500 rpm. It can be done but would be way way way over my budget.

 

man, thats sick. never heard a peripheral port run in person...cant wait to hear it in may. just curious, what kind of carb and how much fuel is it good for?

 

The carb is a 51 Weber IDA. It flows about 700 cfm of fuel, it is fed by a Mallory Fuel Pump that puts out 140 GALLONS (not liters) per hour. We run about 7-8psi of fuel pressure with a return system from the regulator. Then car at Mosport will use about 8 gallons of gas in 20 minutes of racing. We do about 15 laps in 20 minutes and each lap about 4kms or 2.459 miles. That equals about 4.6 miles per gallon or 61.4L/100kmh

 

just to put that into prospective i average anywhere from 30L-45L per 100km on a track day

 

wow, thats pretty crazy. I want to put something like that in my FB when its all done...but its not realistic or necessary for a car that will likely only see a race track once or twice.

i always wondered, what happens to the original intake ports when you go the peripheral port way? do they get covered over or do yous till use them, just for some moral support for the gaping holes now in the rotor housings? Al, i cant really tell from the pics either. all you can see is the two tubes running to each of the new ports and you cant make anything out in between there.

 

We use 4-port turbo side plates from a 1989-1991 RX7. We completely fill the stock ports with Devcon Ceramic Putty. We also seal off the injector ports and the oil injection ports as well. We run 100/1 premix 2 stroke racing oil i the fuel, thats why it is always smokie on start up.

Btw, she fired on the 1st crank tonight, 125lbs oil pressure at 1700rpm idle. (lol) We need to clean the carb again (thats for all you premix guys with the stock oil injection) and set the timing with a timing light that can read through the 10mm ignition wires.

 

ah, good to know. You use those plates for any specific reason? smaller ports to fill or something? and grats on the good easy start up. i bet you're just chomping at the bit for the race season to start now eh. haha.

 

Yes the turbo plates are easier to block up and supposedly they are stronger as well.

 

So you're saying aside from cost, there is no technological advantage to running a carburetor vs EFI? From my understanding, EFI will better atomize the particles thus promoting a more efficient combustion process.

 

Al, that's looks amazing. I just aspire to get me car as cleaned up and well prepared as yours. (But I'm working on it.)

Not to drag your thread down, but, since I currently have the same Carb as you, I'm wondering (other than who your sourced the air filter from, as I need one now that I've "adjusted" the hood enough now to clear one) do you have more information on how you set up your ignition?
I seem to be having serious issues with noise on my ignition (can't get a clean tack signal) and it's breaking p at higher RPM. Getting that sorted is my main project for this winter, so any info on how you have ours set up would be great.

Also, 7-8psi on the Weber? Wow... as I recall, Racing Beat told me under 5psi. Any more info on your fueling setup as well?

 

No... that's not what he's saying.

What he's saying is that in order to get FI working properly wuth a PP you have to spend stupid amounts of money and be willing to turn a blind eye towards all the others who've tried and ended up blowing engines, or having to limit how high it can rev too. The only people who've really been able to get it to work properly is mazda themselves..

 

What? Al's race car is FI??? I thought it was NA!

 

I think you are just being smartypants (which you are haha)

Of course he meant Fuel Injection not Forced Induction...he may miss the "E" part keke

 

We run the higher pressure because we have a "gross jet" for the main jet. That allows you to run higher and more consistent fuel pressure. If yoru running a 51 weber on a bridgeport you are wayyyyyyyyyyyyyy over fuelled, thats why your breaking up at higher rpm. We had the 51 jetted down to a 48 or below when we ran a bridgeport. I think we have 42 chokes in it now, Racing Beat says to run 46's on the Pport.

 

I seriously thought he was talking about forced-induction when we wrote FI.

 

Thanks Al. We've got the 51 choked down a lot and the jets smaller. Partially went with the 51 so that I had it when the budget allows me to go PP down the road. (Also, at the time, Racing Beat, and Rotary Racing and Reliability in Cali both recommended it.)
Still sorting out the fuel, but have an ignition issue as well. Friend of mine who built my gauge package could barely get a clean signal to run the tach (he had to average across 25 ignition pulses and reject the outliers to get a steady reading) and if I try to dyno the car, once we hit around 6000rpm the signal gets so noisy that the dyno losses the signal and we can't get an RPM reading.
I'm not sure if it's a bad 12A distributor or a bad 6AL, or something else. Also noticed you have 2 ignition boxes, so curious how you have it all wired up, as I know there are dozens of schools of thought on doing ignition in these things.

 

We run seperate leading and trailing MSD 6A and Blaster Coils one box and coil per side. We also have the weights in the distributor welded in place so there is no mechanical advance. My rev limiter is my right foot lol. What rpm chip do you have in the MSD6AL box?

 

That's about what I get in the city. Highway is a little better

 

Mine is actually the Mallory 6AL, which is pretty much the same box. (They even look the same.) Except, RPM is set with DIP switches. (It was what the local shop had in stock when I needed it RIGHT NOW. )
I've tried a few different setups, but currently the car is set up with the 6AL running MSD Blaster 2 coils direct-fire to the leading plugs, with another coil running the trailing off the cap.
I tried a few setups, but the car always seemed to run best with direct fire.

While it doesn't explain my poor signal, you do bring up a good point about the weights in the distributor. I don't believe mine are welded.