stock ls1 head flow

**stangslayer98** · 06-06-2008, 09:50 AM

i was wondering what is the biggest valve an ls1 head can have and what would be the maximum flow the head can have after being ported

**OnEbAdReDSS** · 06-06-2008, 10:03 AM

you can port them as far as you want... what i have read and from experiance with other engines... is port the intake runner to the same with a LS6 Manifold then Port match the headers with the exhaust runner... now for valves i think you can go up to 2.055 on the intake valve before serious modifications to the head and a 1.6 exhaust. A lot of builders back in the day with the LS1 Heads do the port match and polish w/ 2.055 intake valve and a 1.60 valve... with a ls6 manifold and a 221/221 cam they made over 420 hp

**OnEbAdReDSS** · 06-06-2008, 10:04 AM

this is what i am planning on doing with my heads when we do a stroker this winter

**stangslayer98** · 06-06-2008, 10:39 AM

i was looking into geting a set of ported heads the shop owner/tech told me after porting his heads flow 300cfm i dont know at what lift though. he charges $850 plus core exchange

**OnEbAdReDSS** · 06-06-2008, 04:50 PM

thats not bad at at!

**BlwnCamaro** · 06-06-2008, 07:29 PM

Originally Posted by stangslayer98

i was looking into geting a set of ported heads the shop owner/tech told me after porting his heads flow 300cfm i dont know at what lift though. he charges $850 plus core exchange

not impossible but on the high side for port job on stock heads, probably more realistic is like 275 cfm at around .600 lift on stock ported to the max head. 300+ is more like aftermarket head territory. They probably flow low 200's stock maybe 230 at most. Tell this guy to provide flow chart numbers not being rude but to back up claims. I port heads but dont have flow bench so am not bragging numbers but if you know what you are doing the results speak for themselves. Any other flow bench guys please correct me on the numbers but this should be close for stock and ported ls head. Good luck