Milled 317's
Milled 317's I'm going to have my 317 heads milled on my lq4 by .030", and run a stock head gasket, along with ARP head stud kit. This is on my DD 2007 2500HD Classic CC 4x4, with 4.88 gears, lift and big tires. I have a baby cam in it, and I'll always have a baby cam in it. Clearance shouldn't be a problem with the pistons and valves, but I'm wondering if I should have the intake surfaces milled while I'm at it to help with the intake fitment. If so, how much should I have taken off? Thanks.
TECH Addict
Joined: Aug 2005
Posts: 2,305
Likes: 126
From: Monroe,NY
I would just pick up some 243/799 heads. You will never be able to mill the 317 heads enough to get the compression you would get with the 243/ 799 heads. Then you can switch them in a day instead of taking your heads off to have them milled and waiting to get them back.
FormerVendor
Joined: Jul 2016
Posts: 432
Likes: 7
Removing .030 isn't going to require resurfacing the intake, but like others said if its an option I'd sell the stock 317 heads and run a 243/799 casting that starts you off at a 64cc chamber without any milling.
Thanks guys. I realize that only removing .030" isn't going to get me to the same size combustion chamber as a set of 799s or 243s. The other day I discovered the driver side rear exhaust manifold bolt is broken off in the head. I'm only going to be able to repair it with the head removed. So I was just thinking while I had the head off I could repair the broken exhaust manifold bolt, buy some shorter pushrods, head gaskets, intake gaskets, some arp head studs, some arp exhaust manifold bolts, and have the head milled just enough to bump the compression a little bit, but not enough to cause valve train issues. I do realize that a set of 243s would be my best route, but I'm kinda on a tight budget. And I hate hate hate exhaust leaks. So really this is an exhaust leak repair, with the possibility of picking up a little bit more bottom end. And if I'm correct, I would still have a compression ratio low enough, that if I ever wanted to put a little positive pressure on it with a super charger I could correct? Thanks for the replies so far.
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Thanks everyone for the information. I've decided to just save the money and purchase a set of 799/243 heads, so I don't have the down time of waiting for the heads to be milled. Then I can sell my 317's to make up a little of the money. I'll just find a set of rebuilt heads, and transfer over my valve springs, and call it good.
Now for another question.
I know obviously that I'm going to have my truck tuned once I bump the compression, but will my truck be able to start and run safely with the current tune? The reason I ask, is because I live so far from any tuners. There is no one within 250+ miles of me, that I know that can tune my truck. So I've contacted BBP to get on the list for the next in person tune at Lake Havasu. This is a 5 hour plus drive for me. Would I be able to make the drive? Or would I need to send my ecu into them to get a basic tune first just so I could drive to the in person tune? Thanks for the help so far.
Now for another question.
I know obviously that I'm going to have my truck tuned once I bump the compression, but will my truck be able to start and run safely with the current tune? The reason I ask, is because I live so far from any tuners. There is no one within 250+ miles of me, that I know that can tune my truck. So I've contacted BBP to get on the list for the next in person tune at Lake Havasu. This is a 5 hour plus drive for me. Would I be able to make the drive? Or would I need to send my ecu into them to get a basic tune first just so I could drive to the in person tune? Thanks for the help so far.
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Verdad Gallardo Thanks everyone. The search for some 799's or 243's begins. Some lt headers are in the mix too. Plus I need to step up to a 255 lpm fuel pump. After that, I think I should be happy. I'm already happy with the power now, but I tiny bit more is always nice. Plus I like to tinker.
Well I looked and looked and looked for a set of 799 and 243 heads. I couldn't find a set under 450 shipped that didn't have a million miles on them. 450 for a set of worn out heads, plus another 300 minimum for a rebuild from my uncle comes out to 750-800 bucks, which just was a little too rich for me. So once again I'm back to milling 317s. I found a like new set of 317s with very very low miles, no broken bolts, and basically ready to bolt on. I'm going to have the heads milled .030 which isn't a lot, but it will at least get me over 10:1. I'm going to do a very mild clean up of the casting flaws in the intake and exhaust runners. I'll bolt them back on with stock gaskets, and new hardware. This will give me something to tinker with, give me a couple of ft lbs, and cure my exhaust leak which is driving me crazy. Also keep in mind that I want to put a pro charger on my truck in the future. I should be able to do this at 10:1 on 91 octane comfortably. The only thing I'm trying to sort out now, is where to get it tuned once it's done. I'm on the list with BBP fir their next trip to Lake Havasu, but I have no idea when they'll actually make it back there. So if someone has any suggestions on where I can get a legitimate tune near Page, Az I'm all ears. I'm willing to travel up to 250-300 miles. Thanks.
The milling won't cost me a thing. Family member is cutting them for free. How is a free 5-10 hp and 5-10 ft lb a bad idea? I'm going to clay the valves and check my ptv, even though I should be fine. Worst thing about the whole deal is that I'll have to get a new set of pushrods. But with a new set of heads, you run that risk regardless.
Last edited by PowellSixO; Jan 15, 2017 at 07:42 PM.
Well this isn't going to happen anytime soon. 
I tried to save a little money, and got screwed. A member here on LS1Tech (username KRENZ) did not send the heads after I paid him for them. I'm a little pissed about it honestly. I'm not a rich man, and the 275 I sent him is a pretty big hit to my wallet. It hurts even worse now that I've spent 350 additional dollars on all the necessary gaskets and hardware for the job. I've reported him in the Negative Trader Feedback thread. Seeing as how I sent him a money order, I know I'll never see my money again. Sucks to be me today. Lol. Here is a link to the negative feedback thread. His name is Alexander Ronald Krenz for anyone that might be doing business with the guy. Buyers beware. His username is KRENZ, and he's from Woodworth North Dakota, and his cell number is 701-320-8534.
https://ls1tech.com/forums/negative-...l#post19514812
I tried to save a little money, and got screwed. A member here on LS1Tech (username KRENZ) did not send the heads after I paid him for them. I'm a little pissed about it honestly. I'm not a rich man, and the 275 I sent him is a pretty big hit to my wallet. It hurts even worse now that I've spent 350 additional dollars on all the necessary gaskets and hardware for the job. I've reported him in the Negative Trader Feedback thread. Seeing as how I sent him a money order, I know I'll never see my money again. Sucks to be me today. Lol. Here is a link to the negative feedback thread. His name is Alexander Ronald Krenz for anyone that might be doing business with the guy. Buyers beware. His username is KRENZ, and he's from Woodworth North Dakota, and his cell number is 701-320-8534.
https://ls1tech.com/forums/negative-...l#post19514812
Well after pulling the heads on my truck, thinking i was getting some new heads, i discovered my heads both have cracks. They are cracked between the intake and exhsust valves. So i started looking for another set of heads. Thanks to superman22x, I've got another set of heads coming. He was kind enough to make me a good deal on a set of 243 heads. So after its all said and done, I'll be putting 243 heads on rather than milling my 317s. I'll post some pics later of the progress.