Autolite 2100 carb sugestions

[drukkosz]

I have a 68 mustang conv I6. Currently have Weber 32/36 but would like to upgrade it. I am planning to purchase aluminum head from classic inlines and upgrade my cam to 264/264/10 or 12 open to suggestions as well.


Could you tell me what size carb should I get??

Thank you for your time

 

[68_sixpeashooter]

If your going to get the aluminum head I'd suggest getting the adaptor to the mount a 4v carb.

 

[drukkosz]

Thank you for your response. Now the question is which one??

Should i go with the smallest one Autolite 4100 465cmf? or holley 4610 390?? I have been reading about carburetors for weeks and i think i just getting more and more confused ;(

thank you

 

[ludwig]

You want to get a cfm rating that peaks out at the RPM and speed you plan to drive. If you have a drag car and want max revs, the larger rating is for you. If you plan to use it for a daily driver, the one at about 300 will be a better choice.

There is a formula for calculating the optimum cfm rating. I don't know it offhand but I spent a lot of time calculating these numbers for the I6. I came to about 300 to 350. You might want to start a new string because there are several guys here who can help you with the calcs and give you much better advice than I can.

Nevertheless, I believe you will be over-carbed at 465, especially if you make no other mods to the cam and head.

 

[68_sixpeashooter]

Yea it really all depends what kind of driving you'll be doing. I'm not good on what choosing what cfm to get but if you go on the classic inlines website mike has the formula to calculate your cfm.

 

[drukkosz]

I do more highway but i like to cruse in the city as well. I did use the formula but i got lost on RPM. What RPM our engines have? I dont have the gauge. I assume its close to 5000? using the calculator it did tell me around 300cmf. so does it mean that for example all 4 bb are to big?? the holley 4160 is 390

 

[ludwig]

With a C4 standard auto tranny, you will be driving around 3500 rpm on the highway.

 

[drukkosz]

oh, ok i didnt know that thank you for the info

 

[chad]

Hi Drukkosz!

AND welcome to the forum (I hope it's not too late to say so) & site!

(What is your typical need/driving mix? What result sought?) Do you drive in a typical large USA city (stop'n go, lots of lights & between the block driving?) is it autobahn type highways (sorry don't know kph, more familiar with mph) at 70/80 mph? What % of total 4 each...

I'd agree, a tach purchase/install may B a good 1st step B 4 the alu intake/carb mod. C how you R driving NOW, take some useful data (we're all scientists, no?).

 

[drukkosz]

HI Chad and thank you
I driving style is mixed. probably 50/50 highway/city. I live in Cleveland so traffic is not so bad here. what i am looking for is a nice comfortable ride on the highway with a little kick on the start It would be fun to spin the tires from time to time