To mill or not to mill. That is the question.
#1
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A fellow tech member is putting an engine together for me currently. LS1 block, crank, rods with aftermarket hyper-T flat top pistons. Z06/LS6 243 heads all stock. LS6 cam. This will be going in my 4wd Silverado in my signature. We're building it because the parts are on hand so just going for it. Should I mill the heads? The gaskets are 051 thick. I run premium of course, minimum of 91 octane, many times 93 in my area.
I'm curious as to what my compression will be as is, and how much I can mill without worrying about detonation and PTV clearance. He's headed to a machine shop tomorrow so I'd like to be able to tell him yes or no and how much by tonight. If I can mill these things and get a nice, safe bump I'd like to do it now and touch this engine once. I am NOT looking for any max effort, max cutting number. Just a good, reasonable amount. Milling is relatively cheap so I don't want to leave power and drive-ability on the table because the cost isn't an issue. I'm not looking to change any other parts of the build because it's all there and nearing completion. Anyone have input? Would be greatly appreciated. Thanks.
I'm curious as to what my compression will be as is, and how much I can mill without worrying about detonation and PTV clearance. He's headed to a machine shop tomorrow so I'd like to be able to tell him yes or no and how much by tonight. If I can mill these things and get a nice, safe bump I'd like to do it now and touch this engine once. I am NOT looking for any max effort, max cutting number. Just a good, reasonable amount. Milling is relatively cheap so I don't want to leave power and drive-ability on the table because the cost isn't an issue. I'm not looking to change any other parts of the build because it's all there and nearing completion. Anyone have input? Would be greatly appreciated. Thanks.
Last edited by AnotherWs6; 03-04-2017 at 12:32 PM.
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I would mill some. 11.3:1 would be a good aim. Run tr6 plugs if you do, not the stock. TR55
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I'd still run the tr6. Mainly because you mentioned 91 octane
#6
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If you are going to all this trouble you should really consider a different camshaft. You'll be leaving a lot of low end tourqe on the table with the LS6 cam. Remember that cam was designed for a light weight manual transmission car, not a big heavy truck. There are plenty of mild options out there that will still drive and idle nice, but will move out a lot better than the LS6.
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Originally Posted by stockA4
If you are going to all this trouble you should really consider a different camshaft. You'll be leaving a lot of low end tourqe on the table with the LS6 cam. Remember that cam was designed for a light weight manual transmission car, not a big heavy truck. There are plenty of mild options out there that will still drive and idle nice, but will move out a lot better than the LS6.
#10
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Gonna cut them 20. As far as the cam goes, I'm doing this on the cheap and the parts are on hand. If I want a cam later fine, but I'm sticking with it for now. It matches the springs already in the heads. Keeping it simple. Also, my truck has 4.88's and a 3,200 rpm converter so I think it will be OK. If not well then I learned a lesson first hand. In the mean time I'm still knocking 100 lbs off the truck while adding easily over 100 horsepower. I'll just see how I like it.
#13
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You're going to hate that cam in a truck. Just saying. Keep your eye out for a 220/220 range cam on a narrow lsa, and lifts below .600". Get pushrods, and springs, and be happy. Or waste your time to save a buck, and regret it. It's your call.
#14
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Oh it's only 1 buck for a cam, pushrods and springs? Well S, why didn't you say so earlier? I highly doubt I will hate the cam. What I do hate is the **** 5.3 that doesn't make any power until 2,800 rpm. Hence the 3,200 stall. With my stall I assure you that I am not going to "hate" anything. Have you ever driven a vehicle with a high stall converter? Doesn't matter, you're clearly an internet expert. I'd tell you to blow me but I'm not into that sort of thing. Learn how to talk to people tough guy. Nice lights BTW. You're cool because of them.
#15
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It's just simply a whole lot easier to put a proper cam in the engine now while it's being built, get all the clearances right once and then get it tuned once.
#16
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Thanks, that's why I'm keeping the milling conservative, that seems to be the consensus. Again, with my stall anytime I give even moderate/light throttle I'm at 3 grand right away. Pretty sure an LS6 with bumped compression, headers and true duals is going to be just fine above 3 grand. Thanks though.
#17
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Oh it's only 1 buck for a cam, pushrods and springs? Well S, why didn't you say so earlier? I highly doubt I will hate the cam. What I do hate is the **** 5.3 that doesn't make any power until 2,800 rpm. Hence the 3,200 stall. With my stall I assure you that I am not going to "hate" anything. Have you ever driven a vehicle with a high stall converter? Doesn't matter, you're clearly an internet expert. I'd tell you to blow me but I'm not into that sort of thing. Learn how to talk to people tough guy. Nice lights BTW. You're cool because of them.
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Edit - I'm not talking about the S10 in my sig. That thing is light enough that the LS2/LS6 cam is fine
#19
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I'm not the internet expert, hence me asking questions about milling. Why would I bend a valve or pushrod on a basically stock motor?
This isn't for the motor in my truck. It's a separate, build. Top to bottom. Cam is already in the motor. I set a budget for this thing and I'm sticking to it. Can't be worse than my 312K mile stock 5.3. Bigger, lighter, up 100hp and change. I'm gonna be just fine. My current motor runs strong, I'm changing it because I have access to CHEAP PARTS. Not shitty parts, cheap parts. Otherwise I wouldn't even be talking about a new motor until my current one blew.
I'll report back my dismal results when it's all done.
This isn't for the motor in my truck. It's a separate, build. Top to bottom. Cam is already in the motor. I set a budget for this thing and I'm sticking to it. Can't be worse than my 312K mile stock 5.3. Bigger, lighter, up 100hp and change. I'm gonna be just fine. My current motor runs strong, I'm changing it because I have access to CHEAP PARTS. Not shitty parts, cheap parts. Otherwise I wouldn't even be talking about a new motor until my current one blew.
I'll report back my dismal results when it's all done.