Weber tuning update. 

 

I have not ordered DCOE 45's, but I would love to try.

However I have decided to get my setup even more dialed in. Again, I have run the same setup untouched for 4 years now.  Car starts and drives beautifully. I decided to keep my LM1 wideband out visible while driving lately and found out how incredibly pig rich I was at 3000 rpm 4th gear steady state cruising. I decided that this was a main jet issue not an idle jet issue (due to the rpm) and checked my settings.  My air corrector was a 170 and my main jet was a 130. This combo gave me a 11:1 AFR at 3000 rpm. Far too rich for normal cruising.  This was with whatever Etube that came with my 151 DCOE 40's. I forget, F9 I think.  

 

Anyway, I decided to go down to a 125 main jet and leave the air corrector alone.  Car feels fine, if not a bit more crisp.   At 3000 rpm in 4th gear I am getting 12.3-12.5 AFR. now.  I have a set of 120's I will try this week.  If I can get around 13:1 I will declare victory and call it done. I have a beautiful idle at 850-900 rpm at 13.4:1 AFR. 

 

The webers prove to be so tunable yet again.  If I get these dead set and running perfectly I will have no other choice but to order 45's and start from scratch again.

You should be able to run stoich or even 15 to 1 at 3,000 rpm cruise with those carbs and proper tuning.  Literally, a well tuned set of Webers can almost equal fuel injection curves. Keep tuning. Maybe invest in a AFR gauge to mount permanently in car.  Gotta get the emulsion tubes bang on though...

This is the setup I used to run to achieve 420 hp on a daily driven 1986 Camaro. Could pull 25 mpg on Highway and set record times at Hillclimb. Aircare ( emissions testing ) came out as clean as specs for an FI engine.  Fairly mild cam, good HP figures and broad Torque band. Engine went to 7,200 at Hillclimbs.

https://www.facebook.com/TMPCarbs/

https://www.youtube.com/watch?v=5tKBwAruqXU

 

Edited April 19, 20177 yr by Chickenman

Zedy - Dave Rebello is finishing up dyno'n my engine this week that he built for me (hopefully it will ship the end of next week after the dyno).  I did step up to Mikuni 44's (Custom ported 38's venturi's from Dave) with a bigger header primary,  and moving to a larger exhaust as well.  Really excited wiht the complete increase airflow and horsepower.  Come on now........you know you want to do it!

You get out of my head you evil man!

 

 

On a really cool note. I took the time to mess with my air correctors this weekend.  I swapped out my thermostat and while the engine was warm I had a chance to try out my sync tool.   All of them were close to flowing the same volume of air.  However cylinders number 2 and number 6 were flowing a tad bit less air.  Having never touched my air correctors since the 40's were new, I gave it a shot to see what I could do.  I lightly backed off the jam nut and opened up the screw. The air flow quickly came up to match cylinders 1 and 5 and now all 6 cylinders are dead nuts even at idle.  And speaking of idle, the engine smoothed out even more than it was and it seems to be snappier off idle now.  I guess I am a believer in the air corrector adjustment.

Nothing better than six singing balanced Sidedrafts.........rock on my friend!

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