firebird99

iTrader: (2)

Ok so i finally found a new short block and my question is would i be able to make 400whp with 243 heads or should i pick up some 317's since i have forged flat top pistons and not the stock ones i shouldnt have to mill the 317's as much as if i had the stock pistons correct?.......Thanks Guys

-6.0 60 over
-367/353@50 624/600 lift
-mid length headers(size unknown)
-ory
-borla exhaust open plate
-k&n filter
-forged diamond pistons

◦Lightweight Forging
◦Small Nitrous Applications. 2618 Alloy
◦Ratios figured for -.010" (positive deck)@9.240"
◦Standard 1.5mm x 1.5mm x 3.0mm Ring Package
◦Premium 8620 Wrist Pins Included
◦Gasket Volume=11.8cc
◦Top ring down= .210" to .250"
◦Valve Relief Depth= .165" Intake and .107" Exhaust
Specs:

◦4.060 Bore
◦3.622 Stroke
◦6.098 Rod
◦466 Grams Weight
◦.945 x 2.500 Pin
◦-2.0cc
◦Set of 8
-Stock crank and rods with arp bolts
-ls6 manifold/stock tb

Scooter76

Both are Great heads for what you are aiming for........ with the combo u have listed you should be well over 400rwhp as it is ! probly closer to 450 rwhp with a good tune , Imo dont mill the heads , flat tops will already have you a little over 11-1 compression with 243's !

firebird99

iTrader: (2)

When i bought the motor it came with cometic head gaskets but i dont know how thick they are i was hoping that a machine shop could tell me before i mill anything

firebird99

iTrader: (2)

Forgot to mention that i have mid lenght headers,ory,borla exhaust,msd wires,k&n filter,ls7 clutch and ram aluminum flywheel

firebird99

iTrader: (2)

So i guess that was a stupid question or nobody wants to chime in?

redbird555

iTrader: (14)

the 243 and 317 are the same heads you would make power with the 243 because of the higher compression with 317's you would need to mill the heads down to achieve the same compression

redbird555

iTrader: (14)

but you are correct the 317 wouldnt need to be milled as much

garygnu

get some l92 for more power,you have the big bore to fit the bigger valves.

redbird555

iTrader: (14)

he stated in his other thread he cant affor dthe l92s with the added cost of the intake, tb etc but ya they would make more power

firebird99

iTrader: (2)

Well i managed to pick up a set of Patriot Performance cnc'd 243 heads with all brand new lunati parts and 64cc chambers for a very low price from a guy on craigslist and the website said they flow 302 cfm at 600 and my cam is good for 624/600 so these should work good now i just need a ls6 intake since i cant find a cheap Fast intake so with these heads what do you think ill put down to the tire with a ls6 intake?

redbird555

iTrader: (14)

a guy with a 408 and 799s which are the same as 243 put down 447rwhp with an ms4 cam. Being you have a slightly smaller cam and cubes but better heads id say u throwdown about the same. with 11:1 compression on those heads make sure u always use premium and get a damn good tune so u wont have any knock issues

redbird555

iTrader: (14)

oh sry i didnt see that you were using mid length headers id subract 15hp for that with a built motor if u can get a decent set of lt's for a good price DO IT they go for 250 for a used set and that motor will def appreciate it.