MonteCarlo_Nate336

Hey guys was trying to get some information. My name is Nate/MonteCarlo_Nate and was wondering what needs to be done to achieve 500hp out of a 71 Olds 455 (396021F).
I was planning on changing camshaft (not sure which yet). Double roller timing chain, new performance intake, getting crank balanced, grounded and polished. Stuck pistons unless stocks are not perfected or damaged. Currently has 750 Holley vacuum secondary. Wanted to either get C heads or keeping G heads and get ported milled, polished and valve job. All information will be greatly appreciated.

oldcutlass

I moved your post to the performance section. If you do a search you'll find a lot of info already out there in addition to what ever answers you get with this post. Post a proper intro with pictures when you get a chance.

74sprint

A great place to start would be to read through this thread: https://classicoldsmobile.com/forums...ld-thread.html These are engine builds that members have posted, depending on the weight any car running low 12's or high 11's will be 500 shp. I have stock 'G' heads on my car and they flow 221 cfm which means that the max I can get out of my N/A engine is 426 shp. To get more like 500 shp I would have to port the **** out of them, easier to just go aluminum. To figure out how much airflow you need go to this website: http://www.wallaceracing.com/calcafhp.php, the most your going to get out of the 'G's is about 270 cfm, which is enough for 512 crankshaft Hp.


Good Luck
Ray

Fun71

Stock pistons are deep dish for factory 8.5:1 compression ratio. Prolly gonna be hard to make 500 hp with those.