4.8 NA build

[danger_ranger83]

sounds like it should be sweet......not picking on 4.8s but we had a guy brag that he could get more power out of a built 4.8 than u could out of a 6.0 lol then he got outrun by a fully bolted 4.8.....guess it just depends on how u build it

good luck

[Frenchy]

Don't mill the heads more than .020 IMO.

[SNEEKY]

Is that because it would make the deck of the head to weak? Possibly thinner headgasket? Looking to get a safe but increase my compression here. Best headgasket/ milling to get the most compression without compromising durability

[SNEEKY]

any takers for the best head gasket / milling combo?

[SNEEKY]

guess no1 cares to bother since its a 4.8.... anyway update! got the truck tuned tonight. runs good. got it updated for the cam and t56. all the dash lights went away and the truck runs awesome. i need gears badly! thing wouldnt idle any lower than 1200rpms. guess im gonna have to live with it. (because of how large the cam is in reference to how small of cubic inches i have). also tuner told me hes buying a dyno mid april so hopefully by may ill have numbers by then as well

[George C]

there should be no reason why that cam cant idle at 850-900 in that motor

[straightaxle]

taking the motor out of the truck isnt really an option. but i do understand exactly what your saying.
since they are flat tops, does anyone know the actual compression with a stock headgasket/243 head combo. and also by milling off every.005 how much it would increase the compression? im gonna start googling this to see what i come up with

You don't need to take the engine out to cc the piston volume. It can be done in the car.

Things like head volume are not exact. These are just cast aluminum heads you are working with. I have seen CNC'd chambers that cc to a spec other than advertised. This is why I say to have the machine shop check this and mill accordingly.

Keep in mind you can't add 2 points of compression by cutting the heads. you can only mill the heads so far before bolt holes and intake ports won't line up anymore.

[SNEEKY]

hmm well the motor didnt want to cooperate with the tuner i guess...unless someone wants to live tune it for me think im gonna do some gears and an ls7 clutch before i do heads and intake. but they are in my future sometime this summer.

[blazinblue]

in not sure if a 4.8 has gone 12's n/a, go for it. a 6.0 can hit that cam only, it all depends on the money you have to spend. i started out with a 4.8 im now a 6.0 with a t76 fm turbo will see how it goes

[SNEEKY]

id love to touch that on motor