i have a 1989 d100 dodge truck, with a 318 motor, i was wanting to put a larger cam in, but was needing to know if i need to change the fuel system if the cam is not to big

 

what are the specs of the new cam ? chances are the lines and fuel pump are sufficient.

 

Only Changing the Cam...... Should be ok with what you have....

 

i had a 300 L with a 413 4 bbl. with a 268 degree .430 lift. 360 HP. the same engine in a new yorker had 248 degree .389 lift 340 HP. the 300 L got the same MPG, as the new yorker. very streetable. i think it is close to the magnum cam from the factory now days. a difference is the old one is single pattern. in the late 60s chrysler started useing duel patteren cams. if i remember right they had a little more duration and lift on the ext lobes. giving more power with out to much loss in drivablety.

 

the 89 stock engine will have a smog cam. if you replace it with a reg cam you get some improved power and MPG. i think. the factory started putting smog cams in late 60s or early 70s. and strange thing is in the late 60s they found out that a performance cam had better emissions at low RPM. cause of the intake / ext over lap. so the factory did that on mild cams for emissions. but iam not sure they did that for how long.

 

I would fill out a Comp Cam or Lunati recommendation form and see what they come up with, then post it here and maybe someone has used it and can give real world input.

 

thanks everyone, sorry for taking so long to reply, a little thump is all i need. will let you know what i did, thanks again