Clone head flow
- Thread starter Poorboy1
- Start date
Big Chris
Member
I've been using it and really like it. I can tell you the 223 is a strong performer on the dyno, and I think properly prepared may slightly outperform the 181. Keeping in mind that I focus almost exclusively on plate engines, and I've gone on record saying that IMO the 181 was THE restrictor plate head.
I've been meaning to do a side by side by side with the 158, 181 & the 223. ( I have a brand new unmodified 181, 158, and many 223s) However this time of year is super busy for me, and customers are my priority right now. That said, I haven't gotten a chance to test side by side by side. I have however updated many engines this spring with the 223 and I like what I'm seeing dyno-wise.
I plan to do the same as before and do a comparison as cast, as cast w 3 angle valve job, and ported with a 3 angle valve job. I'll also do a green, purple, blue and open side by side.
Now here is the caveat: In my journey down "porting road", I have found that some heads that show real well on the superflow, dont always show well on the dyno. As a general trend they sure do, but there are exceptions. Why this is, I still haven't figured that out. I suspect that the flow the our engine wants is different than what flows at 28 inches of water. As a matter of fact, one of the tests I'd like to do once I get past the spring rush is determine exactly what vacuum the clone pulls at WOT, and do some flow testing there.
Here was the link to the old testing I did: flow testing.
I've been meaning to do a side by side by side with the 158, 181 & the 223. ( I have a brand new unmodified 181, 158, and many 223s) However this time of year is super busy for me, and customers are my priority right now. That said, I haven't gotten a chance to test side by side by side. I have however updated many engines this spring with the 223 and I like what I'm seeing dyno-wise.
I plan to do the same as before and do a comparison as cast, as cast w 3 angle valve job, and ported with a 3 angle valve job. I'll also do a green, purple, blue and open side by side.
Now here is the caveat: In my journey down "porting road", I have found that some heads that show real well on the superflow, dont always show well on the dyno. As a general trend they sure do, but there are exceptions. Why this is, I still haven't figured that out. I suspect that the flow the our engine wants is different than what flows at 28 inches of water. As a matter of fact, one of the tests I'd like to do once I get past the spring rush is determine exactly what vacuum the clone pulls at WOT, and do some flow testing there.
Here was the link to the old testing I did: flow testing.
Last edited:
Dover Power
Member
Its as good of a cast gead that you will find presently.. Very consistant.... BUT if you are running AKRA rules where you are allowed to port then head casting selection becomes a No Big Deal, pretty much all can be made good in unrestticted, but on the smaller rest classes be in search of smaller sized ports to work with.. JMO
Dustinbuck68
Member
Did you ever do you side by side by side testing of the 158, 181 and 223?
Might be a lower cylinder fill percentage. A good cylinder fill can be determined by the swirling motion induced by an asymmetrical bowl design. Hog wild porting can reduce the swirl and lower fill reducing HP in the end.