: how important is head work?



BranndonC
08-02-04, 02:20 PM
my brother says spend $$$ on head work, but i dont have that much $, so heres what i'm doin
i planned on the ek-01 kit here
http://users.elknet.net/mts/page47.html
and what ever cam shaft Ed (At 500cid.com) recomended, thats 1300 plus cam shaft i think
Ed stated that would make 450 hp or so and 550 or so tq, i think that guestimate is a little high, but he knows his stuff, so i trust him.

i called a local machine shop today and he quited me $105 to machine the block and bore it 30 over. and 350 for head work including parts
these prices sound great, but is there any reason i need to spend more for my application of an offroad vehicle. i want a raliable 500 power numbers around what i stated. :)

lux hauler
08-02-04, 02:37 PM
Which cam? What's the head casting? What kind of head work does that $350 get you?

BranndonC
08-02-04, 02:40 PM
just basically a stock rebuild, hew bardened something er others, new everything i think, hot tanking. i mean would it give me like 10 more HP or like 40?

the cam i'm not sure of, i called ed back today and didnt get an answer, so i'll try back soon
the head is a stock 76 head, which casting is that?

also

he did mention doing a 3 angle valve job in that price and the hardened valve seats, as far as port work, he said they dont do that in shop but he could refer me to a shop. He said port work would be like 300-450 though and i dont want to spend that $ for 10-20 hp, does that price sound right?

lux hauler
08-02-04, 07:22 PM
Ok.....let's start from the beginning here.....
First you need to know what you have. You said the head is a stock 76 head. I'm going to assume that you mean a head from a 1976 engine....? There are two combustion chamber sizes for the 472/500 engines. One head has 120cc chambers ('74-'76), the other has 76cc chambers ('68-'73). I wasn't sure if you meant 1976 or 76cc. If you'll look at the heads, either under the rockers or on one of the exhaust ports you should see some numbers cast into them. I can't remember exactly but I think they might be a series of six digits. The last three numbers is what you want to look for.....250, 902 or 950 (these are the early, 76cc heads). My 120cc heads had the number cast onto the exhaust port of the head....the casting numbers for the later, 120cc heads are 552 and 493. Let us know what you have.

Next, you need to know what you want to do with the engine.....What are you putting it in? What are the plans for that vehicle?
Thowing out a power level you want to achieve isn't really a good way to approach things....especially on a budget. 450 horsepower may or may not do what you want it to do and it may even be complete overkill.

Now.....figure what you can spend. The more power you try to make, the more money it's gunna cost....the more power you have, the harder it's gunna be on the rest of the drivetrain. Don't set your self up for disappointment by building a high power engine without building the rest of the project too. It would be a shame to have lots of money in an engine and not be able to use it 'cause you can't afford to rebuild the tranny or rear end that the engine ate up. Build it so everything can work together.