well i just got a ms4 cam and a set of stock 5.3s that i plan on haven tricked a little. but what i am wondering should i get bigger valves if so what size should i go with. not really worried about driveabilty. i would like to get 420 or more to the wheels if possible. any advice would be greatly appreciated.

 

You'll need bigger valves, fully ported and flycutting your pistons.
That cam is seriously mismatched unless the heads are fully ported and worked on.
So serious it would make sh*t power

 

Too much cam for unported heads, you really need a fast intake setup to take advantage of its potential.

 

well im planing on using the new street warrior intake and am gona have the heads done but im not familiar with valve sizes.

 

For the money that you'd spend to get those done right, I'd sell it and get some ls6 heads. 420 should be doable with a decent intake.

 

heads need to be fully ported.. otherwise its stupid to use an ms4.... you would make more power with a smaller cam..

 

You'll have to flycut

 

+1... you have to use stock valve sizes with the big cams..

 

theres no need for fly cutting the pistons when you have forged pistons with valve reliefs right?

 

Instead of us running around in circles, why don't you spill the beans and give use your motor 's full info so we can answer properly.

 

ok sorry dont mean to be a pain. its a forged 346 minus heads and cam. right now i have a bbk intake and throttle body which will soon be finding a new owner.

 

if you have not bought the cam or heads yet...

you have many options not just a handful..

any cam with afrs
any cam with 5.3s
any cam with trickflows
any cam with ls6s

the list goes on and on and on and on..


if your only shooting for 420.. any decent sized cam with decent heads and a good intake will do the trick...

if you buy afrs or trick flows you can get there with a smaller cam easier..

ms4 prcls6s and ported 9090 will get you there.. i know that from exp..

BUT there are MANY MANY more setups that will get there..

you are asking a VERY open ended question.

 

Im running the 5.3's from tsp and a baby cam with LS6 intake and got 420. Its all a money game man, buy the best heads you can and then get a cam to match your needs/wants.

Oh and the street warrior? Good luck.

 

yea i know. ive already made the decision to go with the ms4. just want the best head setup i can and if i can get more than 420 with the ms4 then thats even better. its just i have a guy thats really good at head work but he cant get the parts for them.

 

you chose your cam before you chose your heads? Kinda backwards, as most choose heads and then a cam to best suit them.
Ok simple answer TFS or AFR, those heads wouldnt even be close to moving the type of air the ms4 needs, your cutting your own throat with 5.3's.

 

backwards..

yes VERY backwards... although sadly, 98% of the people do choose their cam then their heads..

if ALL your looking for is 420rwhp.. ms4 and PRCls6 heads or 5.3 heads will do the job..
BUT! you are going to be leaving a lot on the table.. like said, a set of AFR or something would compliment even more, and then there will probably still be some left..

if your going with 5.3s.. i would drop down to a smaller cam.. you would be over camming your car if you decide on the 5.3s..


QUESTION... why have you decided to go with the Ms4???
(and before you think i hate big cams and this and that... i have an ms4 in my car currently!)

 

If you are set on MS4, get the heads from TSP as well. Since you have reliefs you can run some nice 5.3L milled to your liking for more compression.
Give TSP your setup and let themm take care of ya.

 

ok im getn confused now. i chose the 5.3s first i wanted them for more low end torque but i was told that the ms3 and 4 where suposed to be the best for 5.3s. im going on hear say. but i guess you are saying that ls6s would be the better choice. i havent bought either cam or heads yet. was about to last night but saw this first.

 

ive got a thread a page back about the same thing. i can understand why u want the ms4. If u already have the forged pistons why dont you get the stage 2.5 ls6 from texas speed. that combo should make massive power.

 

Honestly dude you want everything out of the MS4 get AFR or TFS heads. All anyone here is trying to say is that the 5.3's will work, but not as well as the afr/tfs.

If all you want is 420 then get the 5.3's, mill them and get a 224 cam.