American Heritage

... Dont want to use LS7 heads on their LS7
AHP is offering the Ultimate Permanent LS7 cylinder head fix for those that dont want to use the GM LS7 castings...
AHP Stage 3 LS3 heads specifically designed for the LS7/4.125" bore.

These are not your run of the mill LS3 heads. Our stage 3 LS3 heads are CNC ported to increase air flow on both the intake and exhaust ports. The combustion chambers have also been CNC ported to both increase volume (70cc chambers) and airflow. We offer these with our Hardened PM valve guides or our Premium Moldstar90 valve guides. Heads are loaded with Ferrea Hollow SS 2.20" Intake Valves and Ferrea Hollow SS 1.60" exhaust valves. Assembled with your choice of springs.

Some brief flow numbers on our Stage 3 LS3 heads vs the stock gm LS7 heads:
Intake Lift - GM LS7 - AHP Stg3 LS3
.600" 368cfm 367cfm
.650" 352cfm 377cfm
.700" 345cfm 383cfm

Exhaust Lift - GM LS7 - AHP Stg3 LS3
.600" 217cfm 250cfm
.650" 220cfm 254cfm
.700" 222cfm 255cfm







To run these on your C6z06 you will also need a GM or FAST LS3 intake manifold with GM LS3 or FAST fuel rail.

https://americanheritageperformance....cylinder-heads

JABCAT

Why might one choose these over the Archangel heads or the Stage 4 LS7 heads?

ClothSeats

So, the 70cc combustion chambers reduce compression ratio, then?

Sleazy Rider

yeah, what he said.

grinder11

So, these heads flow more on the intake side at .600" lift than .650" lift? Also flow more at .650" than .700"??? I'm assuming inverted numbers, or???

double06

The OEM non-ported GM heads actually begin to flow less after 600 lift. I think that is what the chart was referring to OEM LS7 head.

herwawan

Yeah if you look at the numbers on this post, it does start to flow less past .600" lift.

https://www.corvetteforum.com/forums...-and-data.html

Apocolipse

Area under the curve of max lift is most important. Peak numbers mean fk all.

Pounder

I would love a set of Stock heads (stay in A street, AutoX) that I could be comfortable in driving for 100K without the fear of complete engine failure !!

JMB

What does a stock LS7 head flow on your bench?

herwawan

They shared that in another thread, should answer your question.

Apocolipse

Stock ones do last that long - for many. They made lots of LS7 engines.

Pounder

the KEY word "was comfortable"

Apocolipse

I hear ya there - some people are never comfortable lol no car is bulletproof.

Pounder

I would say the LS 1&6 are pretty much bullitt proof !!!

Apocolipse

Ya the whole 200hp worth haha and actually they do have oiling issues on tracks.

JABCAT

I had one LS1 replaced under warranty & the second (different cars) was starting with the same symptoms before I sold it. There were plenty of LS1s & 6s with oil consumption issues. GM's history of issues with their high-performance engines is the number 1 factor causing me to wait several years before considering the C8 Z06. That and the continued issues with the DCT. I already have an LS7 that I need to spend good money to proactively "fix", I don't need to drop $100k on another ticking timebomb.

Sonicdave

Would a Z06 with these heads be able to make the same power as the regular Package 4 LS7 Heads?

Pounder

our 1999 coupe was at 95k when sold, no issues all all, 2002 Z06 went to 127K plus one set of valve springs, our present 2001 Z06 is at 136k uses no oil or any other issues !!! Both Z06's were AutoX'ed. I would hardly class those in the LS7 category which can disintegrate at the tune of 10 grand or more !!!

Apocolipse

And how much power did those engines make?