DanaliHD

iTrader: (5)

so you say bone stock heads?

moregrip

iTrader: (8)

I disagree. This is the wrong way to design a package IMO if the money is there.

zippy

putting heads on the 408 would be a good idea, but he could have just put heads on the 6.0L also. i like to do stuff like this in steps. the more you change at once, the more problems tend to show up. the other thing is, if he gets the 408 in there and can't get more than say 8psi with the stock heads, going with bigger heads isn't going to be where 2grand would be best spent. for the money of the heads he may be better spending that money on the next size bigger blower. if he can make enough boost to be happy, then he'd just order the heads and dial it in again. one of my customers with a 408 ran his at first with the stock heads and then stepped up to AFR 225's. it was nice to have broken the engine in with the small heads and to see where the gain showed up for the most part. that truck with a 408 naturally asperated pulls 53lbs min through the maf and idles in traffic similar to a stock truck, except with a bit of lope.

zippy

not sure i'd say bone stock, you'll need valve springs because you'll want to go with more cam in the 408. for a referrence point, look how long parish kept his stock heads and the power he made with them. no doubt there will be a gain with good heads, but the better question is whether or not that is the best place to put that much money.

wkdivr

iTrader: (8)

Do the new style (GenIII) heads work better with a good multi angle valve job, like the old small blocks did? Or, is that not needed anymore?

DanaliHD

iTrader: (5)

Ok, how much money are we talking about for a valve job on my stock heads? I can get the wcch heads for $1300ish and not have to worry about how long it will take for my heads to be worked on.

as far as moving up to the next size blower, there isn't one. I'd have to end up switching to turbo or something which would be great and all, but, i can't afford the engine, nevermind another $5000 or more for a turbo.

zippy

all you'd need done is valve springs. those you can do yourself in an afternoon's worth of time. if you do go with the heads, don't go for a fully ported stage 3 type. you're not going to be able to run a big enough cam to take advantage of something heavily ported with that blower. on the other hand if you do go with a mildly ported WCCH head and have them polish the chambers you will certainly see some gains. i'd be guessing that there will probably be around a 30-50hp gain in going with the bigger heads, especially if they polish the chambers. polishing the chambers helps keep KR* down and allows for more timing to be ran than with stock heads. for a camshaft, try and keep the duration under 230º at .050 to keep from having to turn the rpm high. overspinning the blower alot will just make for alot of heat by about the 1/8 mile. if you run a cam with around a 224/228@.050 and lift around .580 or so you will be able to keep the shift points at around 5800 and have a huge torque number at around 3000 or so which is where the stock converter should stall to. it will be a tire spinning machine, even in 4wheel drive.

TieRod

If you go, Go all out! $.02