Removing the B3 camshaft from the front of the engine??

[fujioko]

Hi 'ya folks,

I know the B3 camshaft comes out of the Festiva head from the back side .... but will it also come out from the front?

The reason I'm asking is my B3 is in a rear wheel drive Miata and I don't have the ability to pull the cam from the back unless I pull the head off the engine.


Jim

[blkfordsedan]

Yes, it comes out the front. You'll need to replace the cam seal obviously.

B3 in a Miata, huh? Gas prices must really be out of control! At least you'll never burn the clutch up or tear up the tranny!

[Safety Guy]

Fujioko has put a Geo Metro 3 cyl. into a Miata as well as the B3. There's a thread or two around here that you can read. Very interesting stuff!

Karl

[fujioko]

Thanks!

I know a lot of folks like to ditch the B3 in favor of a Miata or Escort GT engine. I ditched the 1.8 for a 1.3... sort of backwards but I love it!

The three cylinder car is getting ready to go back on the road for the winter.

Jim

[sketchman]

What kind of numbers are you getting now with the B3?

[fujioko]

What kind of numbers are you getting now with the B3?

Hi 'ya Sketchman,

Good question! I have several numbers to report.

The Miata is a lot heavier than a Festiva and the overall drive ratio makes the B3 spin about 500 RPM faster.

So...

I got about 35-36 MPG with a 1993 Festiva ECU

I added an LC-1 wideband O2 and programed an offset to fool the ECU into running at 15.5 AFR. The MPG was 40-42 without air conditioning and 37-38 with air on. The offset worked well in cruising but under hard acceleration the engine would run too lean.

The Megasquirt II delivers 41-42 MPG. The engine runs at 16.1 AFR in cruise and under hard acceleration I get a nice fat mixture (12.5 AFR) Overall the difference in performance is well worth the expense of the megasquirt.

I expect better numbers in the near future and when summer gasoline blend comes back I'll likely see additional improvement.

The engine is nearly stock with the exception that it has coilpack ignition instead of a distributor.

I'm going to run it one more week then switch to a roller cam and rockers.

This project is all about better MPG and not performance, however Any boost in performance without sacrificing MPG is a bonus.

If you are interested just google "B3 miata" and you will find the build thread.


Jim

[blkfordsedan]

What kind of MPG did the stock Miata get? I had a 94 Protege with a B8ME and auto that would get 32 to 34 no matter how hard you drove it. I figured a Miata would do about the same.

[fujioko]

My 02 SE and my 94 got around 27 to 32 mpg. Some folks can get a little more and some folks can get a little less.

My goal is to get 50+ MPG. I think it can be done so I'm giving it a shot.