HELLO I( need some help !) on what color is the best carburetor springs to put in a 440 six barrel motor on the street . The car is a 1970 Road Runner with a 440 engine .Its a automatic car with 410 rear. Engine is 030 with L2355 pistons, Mopar 509 cam, 906 heads with big valves ,214 intake ,181 exhaust ,Hemi valve springs 933, new six barrel intake and carbs, TTI headers with 3" pipes, flowmaster mufflers. I ask a few friends and some says yellow and some says no color on them works the best . We can not feel the end carburetor,s come in at all . Please Help !! You can mail me back on Moparts or my e-mail is mosweethemi@yahoo.com . Thanks Moparts .Carburetor's springs Please Help !!

the colour of the paint is only relevant for the spring manufacturer. on that cam uou have i'd probably go with comp cams 930 spring set up at 1.9 installed height. if you're going to drive that motor in a spirited manner then maybe the 26094 spring. but thats just me.

You are asking about the secondary diaphragm springs right? There is no one-size-fits-all answer. The right springs will depend on a number of factors. Trial and error is the only real way to know which ones work the best for you and your combo.

Do you have a couple of Holley's spring kits? If not, you will need them. If so, on the back of the package is the color and rate chart. Personally, I always start with the quickest opening spring and if there is a bog, swap to a slower opening spring until there is no bog.

My combos have always wanted very light springs.




(This is where I would put the 2 cents...........)

I would start with purple and then progress to yellow. Seems like there were two yellows, a short and a tall, the tall being just a bit stiffer than the short. With the engine off, manually open the center carb fully, and hand operate the back carb to make sure it is not sticking. If not sticking, unscrew diaphragm housing off the carb, push the diaphragm rod up and then put your finger over the vac hole and the rod should stay up, if you have a mity-vac, use it directly on the housing passage and pull a vac and see if it operates and holds vac. If not, you have a torn/leaky diaphragm. You have to test the diaphragm off the carb as there is a kill bleed passage in the carb body that acts like a controlled leak to keep the carbs from coming in too soon.

yellow or purple

My car seems to like the white springs the best.

I agree. My car likes the purples in it.

Purples... 588 solid roller

https://www.youtube.com/watch?v=XoCaHhiqShI

no hesitation.