im lookin to put a new cam in my car i have a 305 and i wanna go with the biggest lift i can go with the factory computer any suggestion?

 

The computer doesn't care how much lift your cam has....
The duration of the cam has more of an effect on how the computer adjusts itself to vacuum and air fuel ratio.

I would say keep your duration under 220 if you want your car to idle properly, otherwise the computer will think it's too rich, too lean over and over again.

Now if you're worried about lift on stock heads keep it below .450" otherwise you'll hit the valve guide retainer and crush your valve seals....

The way I see it, a stock TPI won't breathe up high in the RPMs so keep your choice below 5500...
and since you're running a 305 go with something a step or two above what is stock... which in your case is 202/207 duration with .413/.428" of lift.

This looks like as big as you could go with stock heads.
http://www.summitracing.com/parts/CRN-104221/

Read this https://www.thirdgen.org/mods3

 

actually the biggest cam would be the crane 2032 cam its the 104224 cam... duartion is 214/220 112lsa and 452 465 lift... i had it in my stock headed none tune 350 tpi.... will also work in the 305... the price went up quite abit since i had it two years ago.... i only paid 279 on summit for this exact cam...


http://www.summitracing.com/parts/CRN-104224/

 

Biggest does not equal best performing.

Otherwise this guy I know with a 7.3 Powerstroke F250 that has 16 inch stacks would own the fastest truck in the world.





Bought my new front bumper for the Rustang from him. It was really neat to see this truck in person. The stacks are overkill, but I like it.

 

if those stock were like 5 or 6 inch they would be fine but 16....WTF!!

anyways those two cams are probobly the biggest you can go before doing the heads, which in honestly you should do anyway to maximize what the cam is doing, unless your just looking for a loopy idle