[andy669]

500 RWHP from a N/A 306 is doable, but isnt going to be streetable. But, that depends on your version of streetable. My 306 that made 420RWHP with a limited selection of parts wasnt very streetable.

500 'streetable' RWHP from a 306 is easy, and can be done for around $17,000 including upgrading the drivetrain as well. A stock block will work just fine if the engine is tuned right. Saying that 500 RWHP is the limit for a stock block, perpetuates a myth that as soon as you see 500, the block is going to split. Thats not true at all. A stock block can take much more than that for extended periods of time, but you want to make sure the tune is right. Start detonating a few cylinders and you will have problems in a hurry.

Heres how I see it:

$4000 for a decent shortblock with stock cam
$1500 TFS TW heads, pushrods, rockers, and upgraded springs
$1500 TFS Street Heat intake, 80mm TB, Mass Air Meter, Power
Pipe
$800 Aluminum Flywheel and good clutch
$1000 AFM PMS
$500 72lb injectors
$2500 Vortech V2 SQ 6.87 lower and 3.33 upper
$1500 Tremec TKO
$250 FMS Aluminum driveshaft
$1000 Decent axles, Gears, Detroit Locker
$1500 Sumped tank, braided line, Eliminator pump, fittings, filter
$1000 1 3/4 shorties, 3" h-pipe, 3" catback

This combo will make around 490 with 93 octane and 20 degrees of timing. Put 100 octane and 25 degrees and if its put together right it will make 550.

Andy