If he is already building the motor he could do both. (383 ci can hold more boosted air than a 350). *veiw from under the shade tree*

 

ok, how about a real cheap upgrade just for instance... my motor is close to stock inside, has a new edlebrock 600 and weiend intake and a new hydraulic crane cam with about a 500 lift i think... if that sounds right. what i'm wondering is if i could just put a new set of like 64cc aluminum heads and some forged pistons in the motor and achieve like 10.5:1 compression ratio without having to bore or replace anything else? first of all, would it work or is it not possible, secondly, what else would be a have to in order to do it, and thirdly, what kind of power would i get outta that? i'm open for suggestions.... thanks for all the input so far guys, i'm learning slowly...

 

For something like that a nice 100 shot would do the trick.

If the cylinders are fine (no scratches your nail can hang in) you could get away with a ball hone and new pistons and rings.
If youre adding a point or more of compression, you'll need to rethink your ign timing and fuel a little, maybe even drop a heat range in plugs.

 

Just wanted to say thanks to the guys making huge posts with lots of good info.

 

i'm still wondering about my last post, i'm wondering if i can just put some new heads and cylinders in my motor and get some decent hp...

 

Clarify a bit , I think you mispoke when you said , new cylinders.
Unless of course you mean pistons.

But I think you were meaning heads and camshaft correct?

 

Okay, Lets assume you keep as many parts as you can, but want to make the 400 honest horsepower. What's your budget? Do you have access to a die grinder? If so, lets do this:

1) Keep short block, retain existing crankshaft and rods, but upgrade rod bolts. Have block cleaned and freshened up for some mid-priced pistons. Hmm, in fact,,,, I think I have a used set of +.030 forged TRW pistons laying around here that have had the tops freshly ceramic coated for nitrous.... Just about perfect for a budget rebuild! ($1000 for machine services, piston rings, bearings, seals, gaskets, and pistons)

2) Buy a good performance hydraulic flat tappet cam that's ground for Nitrous Oxide. (Comp Cams P/N 12-264-4) 230/244 dur @ .050, 113 LSA. ($160)

3) Install a set of Vortech cylinder heads that you have cleaned up with a few hours of sanding rolls. Or, just run them as-is, but double-check the valvetrain's clearance (.501" total valve lift) and make sure to install the Comp valve springs & retainers. ($850)

4) Get a used set of true roller rocker arms, 1.5 ratio. ($160)

5) Buy the Edelbrock intake that fits the Vortech heads ($450 ? )

6) Install a used nitrous wet kit with a carb plate. ($350)

That's still nearly $3000. About the only way you are going to cut costs any more than that is to buy used performance heads, buy a used intake, and to do most of the shortblock assembly yourself.

 

yes sorry i mispoke, i meant new heads and pistons... on that post i wasn't really talking about gettin 400 hp so much. that was more of a question of what will new heads and pistons get me if i targeted like 10:1 compression ratio with like some slightly used 64 cc aluminum heads or so? i didn't really wanna buy a new intake and cam becuase i already put those in a few months ago along with the edelbrock 600 and i wanted to know what kind of hp i could get from the heads and pistons. will the rest of my motor be able to hold up to that 10:1 compression ratio(i.e. rods, crank, rod bolts, ect..)?

 

I'm gonna hafta suggest buying a short block 383 or the like. It's definitely the most economical and if you haven't built an engine before I wouldn't spend 1000's on parts and try it....there are some tight tolerances that need to be checked and some specialized tools needed to assemble an engine to be reliable. All in all...I've spent close to $12K on my engine now...
Crank, rods, pistons - $2500
AFR 195's - $1800
Comp cams valvetrain - $500-600
MR intake - $1200
Fuel lines, larger injectors, TB - $800
oil pan/pump, water pump etc - $500
SLP coated headers - $600
Balancer, flexplate, starter, ARP bolts, gaskets, seals, misc. stuff - $1000+
Machine work, assembly, etc - $2000+
Engine dyno - $500
etc........

In hindsight I probably would have bought a built forged shortblock and built the topend myself, but now I know for next time.

- Joel