Thread: 305 Valve lift?

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Whats the highest recommended lift for stock 305 heads, I'm just trying to get a little more torque out my of a 305 rather than swaping it for a 350

If they are Vortec heads, .470 is maximum.

Originally posted by dcurtis
Whats the highest recommended lift for stock 305 heads, I'm just trying to get a little more torque out my of a 305 rather than swaping it for a 350

HAVE YOU VALVE SPRINGS CHECKED BEFORE YOU GO PUTTING ANOTHER CAM IN IT.

the biggest cam lobe lift that can safely be handled by stock springs pre 87 are .500......and vortecs less than that.....but on the other hand.....if you are going to run a bigger cam with stock valvetrain i would use nothing bigger than a 216@.050 and a lift of about .450".....reason being, old springs tend to loose their strength with the test of time.....any decent bigger cam would be better with the matching springs.....much safer in the long run....no use putting all you time in a cam swap and then breaking the springs a short time later casue usually when a spring breaks it will also take a lobe out with it......I have seen bigger cams used on stock springs but IMO thats playin with fire.....take your time and do it right the first time.......you will be thankful in the end knowing that your entire valvetrain is matched and will withstand a beating when tested.....hope this helps.

Well, for the umpteenth time, I'll say it again.
EVERYBODY STARTS ON THE WRONG END OF THE CAR.

Install a looser converter and numerically higher rear gear and you may find that you don't need more cam. Without changing the converter and gear, your cam change will just move the effective window of operation of the motor higher in the rpm band, away from streetability.

well.......instead instead of repeating yourself for the umpteenth time, maybe answering each question and then follow with a recommendation will help the person out alot better than having to make the same statement more than once.......so far he has received an answer to his question and with your post a possible gear and convertor change.....for all I know he may have already done a gear and convertor swap.......and is seeking a little more power form the motor.....this person seeking an answer to his question might not have read your 5000+ posts indicating for the umteenth time. Can't presume some of the people asking questions are going to remember all of your posts in the threads....I like to answer the question asked then if i can make a suggestion i will, but i dont presume other parts on the car......

Curtis , highest lift isnt going to give your 305 more torque.

Originally posted by stepside454
Curtis , highest lift isnt going to give your 305 more torque.

WHY DON'T YOU TAKE A LOOK AT SOME OF THE AFTERMARKET CAMSHAFT'S.WELL WOULD YOU TAKE A LOOK AT THAT MORE LIFT THAN A STOCK CAM.IF YOU WANT TO BUILD TORQUE THE GENERAL IDEA IS OPEN THE VALVE QUICKLY AND THEN SHUT IT QUICKLY THUS BUILDING VELOCITY OF THE FUEL AND AIR CHARGE.I MIGHT OF OVER SIMPLIFIED THINGS LIKE YOU CAN'T HAVE TO FAST A RAMP RATE BECAUSE THE LIFTER WILL DIG INTO THE LOBE BUT I THINK YOU GET THE GENERAL IDEA.

maybe more lift...but not the highest lift. Id be more concerned with duration & valve timing than actual valve lift. you can open the valve as far as you want ....but if it doesnt open...& close in a manner that is benefecial to producing torque for this application, it isnt going to do any good

Originally posted by stepside454
maybe more lift...but not the highest lift. Id be more concerned with duration & valve timing than actual valve lift. you can open the valve as far as you want ....but if it doesnt open...& close in a manner that is benefecial to producing torque for this application, it isnt going to do any good

AS LONG AS HE KNOWS THIS HE WILL BE FINE IN MAKING A CAM CHOICE.

I don't need a stall as I plan to use the stock one, I have a turbo 400 tranny with 3.73 posi gears, the 305 is completly stock so all I wanted to do was basically make sure the heads would handle something like a performer carb,intake and cam to help out the lack of torque, I'm not planning on anything outragious just a little more torque. Thanks for your replies

curtis, yes itll handle it. as far as the carb goes, Id recomend a 500 cfm