Stock L92 Head Flow Data
i would think that these heads were gonna be used on the lowest cube
as 364 ci
i dont think i would even use these heads on 4 in bore
i am going to a 4.06 bore just for peace of mind
or a 375 ci
or use the 4.06 bore with a 4 in stroke to build 414 ci
streetnstrip:
plz pst p/n for valves and related valvetrain parts
like rocker stands,spring seats,valve seals
for these heads
thanx
think about this:
for decades guys have been hogging out intake runners... with a large cam, large displacement, you make large peak numbers.. great for racing.
but on the street, you end up with the usual drives shitty drag car. the "area under the curve" drops waaay down when you're not using that big port.
so AFR and other cyl head guys work their best to make a large flowing head, that also has enough velocity to work on lesser flowing motors... like everything, its a compromise.. and for 90% of the market, it works better..
CC is a ok way to compare ports in the same way that PSI is a OK way to compare boost.... in other words, its somewhat related, but really doesnt mean squat. lol.
think about the millions in R&D work GM put into the LS7 head program.. they're using what they learned there on their massed produced cars.. the less intake restriction, the better. and with this new cyl deactivation routine, these engines will be seeing double the airflow in each cyl. GM figured out a way to make these heads flow alot and work well thru alot of R&D.
companies like ETP and AFR are somewhat limited in that they have to remain close to "stock ports".. otherwise, headers, intakes, ect would come into play, and you'd end up spending waaay too much for those heads to work for you. so even if they know widening the port, doing xyz makes the head flow better, they cant do it. GM did not have this limitation.
really, these heads probably arnt going to be best for everyone.. but for the engine im trying to build, i believe it will work great. im also not expecting an ideal street car. lol.
Also i seen ome of these heads on ebay, and wanted to find out if you can run regular LS1 type headers on them, or do you have to have L92/LS7 specific manifolds/headers.
These really do seem to good to be true.
Also, does anybody have the part number for the holden intake manifold, i think the truck one will be way to tall to fit in am f-body or corvette or the GTO. Thanks
The Best V8 Stories One Small Block at Time
P.S.
Are these 12° heads like the LS7?
These are essentially a unported LS7 head on a 15 degree valve angle.
Nate
Not trying to discourage experimentation. Just a little caution for us amateurs.
I remember when we thought 200cc Intake Ports were to much for a street small block.

PS A little Birdy told me that a better high rpm intake for the L92 heads will appear on the 2008 Vette (425 bhp 6.2L).
Gene
Brandon
The LS1 and LS6 heads had pretty large volume intake runners. GM seems to be keeping with tradition on making large volume intake runners for the Gen 3 and Gen 4 engines. Looks like the intake ports will develop nice airflow gains with minimal port work. This head will be a very impressive street car head.
Richard
Brandon
https://ls1tech.com/forums/showthrea...t=l92+variable
It uses a variable cam sprocket of some sort (Advance/ retard cam timing).
https://ls1tech.com/forums/showthrea...t=l92+variable
It uses a variable cam sprocket of some sort (Advance/ retard cam timing).
Nate





