Single carb vs dual carb

[durden510]

Hi there, I have a 69 2 door 510, had this for a few years never had a "fixer upper" before this, so forgive me for prettty much being a newbie but have recently got renewed interest in it and want to get it more to a daily driver status.

 

Its an L20b, with dual 40" webers, pretty hot cam (from what knowledgeable friends could tell) and high compression (maybe 11:1?) from what some experts in bay area and some friends they said I have too much carburetion for this engine. The guy who sold it to me was looking into putting single carb on it if he wasn't going to sell it, and I'm thinking about doing the same thing.

 

My desire is to cut down on gas consumption and keep it powerful on the low end but still OK on the highway when I want to pass someone. Is this a no brainer for someone looking to turn his dime into a daily driver? Or will I lose to much top end for it to be worth the change?

 

I appreciate all of your thoughts in helping this newbie out! :)

[Jesse C.]

I doubt you have too much carburetion going on, maybe badly tuned carbs, but not too much. I ran dual Mikunis on a L18 with a mild cam and SSS head. If you want better mileage though, you might want to switch to a 32/36 Weber carb. Better mileage and will tame your car down enough for daily driving but yet give you plenty of get up and go when on the freeway.

 

Welcome To Ratsun and you should post some pics soon before they bring out the pitchforks and torches! ;)

[ggzilla]

40s are the recommended size for a 1.6 liter engine. If they are tuned correctly (right size venturis) you can get 30+ mpg. Same story with the 32/36... must be tuned carefully. Just don't put your foot down so much. The stock carb is over-small, so it doesn't matter if you keep it floored.

[68Datsun510]

Would 40's on an 828 manifold work well with a big bore L18/closed chamber head/medium cam??? THeres a set available to me...

[flatcat19]

OIC's, or it didn't happen.