School me on LS7 Head Milling
#1
School me on LS7 Head Milling
Hey guys,
I'm swapping an LS7 into my C5Z pretty soon and everything is going smoothly.
The only thing i'm worried about was the LS7 exhaust valve issue so the shop who is doing my work here in Houston is going to install bronze valve guides and stainless steel exhaust valves.
They also added that the heads could be milled .030" for an extra fee... it would make a friendly pump gas compression at 11.7:1.
What are the pro's and cons on doing this? The exhaust valves and guides are are a for sure but i'm still a little skeptical about the milling.
Thoughts?
I'm swapping an LS7 into my C5Z pretty soon and everything is going smoothly.
The only thing i'm worried about was the LS7 exhaust valve issue so the shop who is doing my work here in Houston is going to install bronze valve guides and stainless steel exhaust valves.
They also added that the heads could be milled .030" for an extra fee... it would make a friendly pump gas compression at 11.7:1.
What are the pro's and cons on doing this? The exhaust valves and guides are are a for sure but i'm still a little skeptical about the milling.
Thoughts?
#2
TECH Fanatic
iTrader: (9)
Join Date: Apr 2012
Location: Georgetown, Tx
Posts: 1,053
Likes: 0
Received 0 Likes
on
0 Posts
Hey guys,
I'm swapping an LS7 into my C5Z pretty soon and everything is going smoothly.
The only thing i'm worried about was the LS7 exhaust valve issue so the shop who is doing my work here in Houston is going to install bronze valve guides and stainless steel exhaust valves.
They also added that the heads could be milled .030" for an extra fee... it would make a friendly pump gas compression at 11.7:1.
What are the pro's and cons on doing this? The exhaust valves and guides are are a for sure but i'm still a little skeptical about the milling.
Thoughts?
I'm swapping an LS7 into my C5Z pretty soon and everything is going smoothly.
The only thing i'm worried about was the LS7 exhaust valve issue so the shop who is doing my work here in Houston is going to install bronze valve guides and stainless steel exhaust valves.
They also added that the heads could be milled .030" for an extra fee... it would make a friendly pump gas compression at 11.7:1.
What are the pro's and cons on doing this? The exhaust valves and guides are are a for sure but i'm still a little skeptical about the milling.
Thoughts?
Milling will give you better throttle response, but I can tell you, from your stock LS6, this LS7 will seem like Superman! With a mild cam like the torquer, you will be adding more than 150 rear wheel! You won't believe how much of a torque monster that motor already is as well! Your tires will be getting a serious workout!
#5
TECH Fanatic
iTrader: (9)
Join Date: Apr 2012
Location: Georgetown, Tx
Posts: 1,053
Likes: 0
Received 0 Likes
on
0 Posts
You should be fine working with 510. Personally, I wouldn't just b/c I've seen great results w/o milling. The other thing is, if you do mill, keep in mind a CC is lost every .006 you mill. So, .030 will cut down 5cc's which will put them @ 65cc's. a cam will change your dynamic compression, so you should be fine. Tuning shouldn't be an issue. The LS7 is a bad motor, it doesn't take much to make great power. You don't need a huge overlap pain in the *** to drive cam to make big numbers. The torquer 116 has put down 550 wheel pretty consistently, and the 110 puts down 565 pretty consistently. Both a pretty mild and good driver cams. The new Katech Kavorka out performs both and is supposedly a better driver cam than the 110.
#7
You should be fine working with 510. Personally, I wouldn't just b/c I've seen great results w/o milling. The other thing is, if you do mill, keep in mind a CC is lost every .006 you mill. So, .030 will cut down 5cc's which will put them @ 65cc's. a cam will change your dynamic compression, so you should be fine. Tuning shouldn't be an issue. The LS7 is a bad motor, it doesn't take much to make great power. You don't need a huge overlap pain in the *** to drive cam to make big numbers. The torquer 116 has put down 550 wheel pretty consistently, and the 110 puts down 565 pretty consistently. Both a pretty mild and good driver cams. The new Katech Kavorka out performs both and is supposedly a better driver cam than the 110.
Trending Topics
#9
Sawzall and Welder Mod
iTrader: (46)
When you change to a camshaft with more duration, specifically more intake duration, the intake valve closing angle (IVC) is later in the compression stroke. This means the upward moving piston travels farther before the intake valve closes, dropping your dynamic compression.
Raising your static compression by milling the heads will help with all over power and especially drivability, but be aware of your piston to valve clearance.
Raising your static compression by milling the heads will help with all over power and especially drivability, but be aware of your piston to valve clearance.
#10
I had my LS7 heads milled 30 thou. I'm running the QM600 cam and this setup gives me almost 9:1 dynamic compression. Now the Torquer 110 and milled heads would move the dynamic compression to almost 10:1, way too much for today's gas.
Talk to whoever is specing your cam, he needs to know what you are doing to the heads.
Talk to whoever is specing your cam, he needs to know what you are doing to the heads.
#11
TECH Fanatic
iTrader: (9)
Join Date: Apr 2012
Location: Georgetown, Tx
Posts: 1,053
Likes: 0
Received 0 Likes
on
0 Posts
I had my LS7 heads milled 30 thou. I'm running the QM600 cam and this setup gives me almost 9:1 dynamic compression. Now the Torquer 110 and milled heads would move the dynamic compression to almost 10:1, way too much for today's gas.
Talk to whoever is specing your cam, he needs to know what you are doing to the heads.
Talk to whoever is specing your cam, he needs to know what you are doing to the heads.
Last edited by 427zm; 07-18-2013 at 08:15 AM.
#12
TECH Fanatic
iTrader: (9)
Join Date: Apr 2012
Location: Georgetown, Tx
Posts: 1,053
Likes: 0
Received 0 Likes
on
0 Posts
I had my LS7 heads milled 30 thou. I'm running the QM600 cam and this setup gives me almost 9:1 dynamic compression. Now the Torquer 110 and milled heads would move the dynamic compression to almost 10:1, way too much for today's gas.
Talk to whoever is specing your cam, he needs to know what you are doing to the heads.
Talk to whoever is specing your cam, he needs to know what you are doing to the heads.
BTW, looks like the QM 600 made some mad power in your setup it looks like!
#13
"BTW, looks like the QM 600 made some mad power in your setup it looks like! "
thanks, it made 572 sae N/A. The 682 is with a 100 shot of N2O.
#14
Moderator
iTrader: (20)
Higher compression helps make more torque, horsepower, and even better fuel mileage as long as the fuel can support it.
#15
TECH Resident
iTrader: (4)
Join Date: Dec 2003
Location: Huntsville, AL
Posts: 859
Likes: 0
Received 0 Likes
on
0 Posts
so mine where milled .039?? probably .040 is what I am going to assume because the ".006 for every 1cc" ratio was rounded?
thanks ahead of time for the response.