TheTwinTurboRX-7

Ok so now my car runs right. Now it needs to be tuned. I know not a lot about tuning carbs but I learn quick. Have the basics for carb tuning but I need an idea of what does what on my carb. Car has a Webber 45dcoe so I need to know what all the adjusting screws do and so forth. Also would appreciate any Webber specific tuning information. Thanks so much guys.

Ben

680RWHP12A

without knowing any specifics of your car, typically a 45 runs good with 36 venturies, 170 fuel jets, 160 air jets, f11 emulsion tubes, a 0 bypass on the acc. pump.2 to 3 turns out on the mixture screws ... this is a typical setup on a 12a with exhaust, stock port at 500 feet alt.

TheTwinTurboRX-7

thanks
I have a stock port 12a with racing beat streetport exhaust
all emissions removed
high flow pump
no A/C or omp
running below sea level or right at it

Also see above question about what everything does since I am not familiar with carb tuning and also how is it possible to tell what is already in the carb.

mperformance

170 jets for fuel are a bit high...but yeap he mentioned at 500ft above sea. For sea level I suggest a bit smaller.


You can see the venturis inside the carbs by looking into the barrels...they have a stamp on it. 36 is the correct size for your application like 680rwhp12a mentioned. The emulsion tubes and jets you can check by taking them out by unscrewing the top round cover and removing the 4 screws which are the tubes. Take them out and you will see the jets at the tip.

you also have a streetport exhaust so you should tune your carb to your liking and that takes practice but baseline figures are good to make tuning a bit easier.

hope that helps

TheTwinTurboRX-7

that helps some yes, maybe someone can still tell me what all the adjustment screws do or direct me to a diagram.

mperformance

the two screws only adjust the idle...not really that much of an adjustment.

pillage6

Doesn't the higher number emulsion tubes mean it will lean out at higher RPM's?

TheTwinTurboRX-7

ahh ok I got ya
so then my other question would be basics about the carb
how to change jets and so forth
again I have never tuned a carb before
maybe a book on webbers I could pick up or even if the carb came with a book of some kind and someone still has it.

Felix Wankel

That carb only came with an intake, air filters, and some packing foam.

RotorMotorDriver

iTrader: (1)

Go to the library. Youd be surprised what you can find . My local library has the actual FSM for 84-85 . Too bad theyre "reference" and cant be checked out, and they charge $0.10 per copy .

~T.J.

pillage6

What is wrong when I crack open the throttle and the car dies?

I have looked for vacuum leaks but found none.