Ring gap, max boost stock?
12-17-2014, 11:06 PM
#2
Restricted User
Depends. High mileage motors have slightly wider gaps from wear.
If you keep the rings cool, they won't expand as much and you can get away with more. This is where water injection comes in.. or E85.
I asked this same question not long ago, there were a few guys making 800 or so to the wheels without opening up the ring gaps. I wish I hadn't taken my motor apart to open them up, especially since I had one bad top ring that was .028 gap but I noticed it had a slight chip it in so the edge facing the cylinder wall is closer to .040. I said screw it and put it back together. I'll run it this spring/summer and rebuild it next winter. I don't have time to mess with it. I would have probably never known had I not taken it apart.
If you keep the rings cool, they won't expand as much and you can get away with more. This is where water injection comes in.. or E85.
I asked this same question not long ago, there were a few guys making 800 or so to the wheels without opening up the ring gaps. I wish I hadn't taken my motor apart to open them up, especially since I had one bad top ring that was .028 gap but I noticed it had a slight chip it in so the edge facing the cylinder wall is closer to .040. I said screw it and put it back together. I'll run it this spring/summer and rebuild it next winter. I don't have time to mess with it. I would have probably never known had I not taken it apart.
12-18-2014, 11:00 AM
#4
Regarding a yard motor the consensus is leave 'em alone if the engine has some mileage (over 100K), less than that you should check. My 77k mile L9Q one or 2 at like .014-.015 IIRC and most like .019. Likely too tight for pump gas. Opened them to .026, one I made too big at .028 and stuck that into cyl #7 which is supposedly the "problem" cylinder. Suprising no blow-by or even the smell of oil at all.
12-18-2014, 11:32 AM
#5
I'd say 800 on a gen3 5.3 is a little sketchy.
With E85 alone, Stock48 runs 20/28 on his rings. Thats a 4" bore. You really shouldn't need over that on a 3.79" bore 5.3/4.8. According to Stock48, large gaps caused quite a bit of power loss. .026 on the top ring is excessive on a small bore motor IMO. Even on pump gas.
.005 -.006 X bore is typical for mild turbo engines.
With E85 alone, Stock48 runs 20/28 on his rings. Thats a 4" bore. You really shouldn't need over that on a 3.79" bore 5.3/4.8. According to Stock48, large gaps caused quite a bit of power loss. .026 on the top ring is excessive on a small bore motor IMO. Even on pump gas.
.005 -.006 X bore is typical for mild turbo engines.
12-18-2014, 11:54 AM
#6
I'm stuck on what direction to go. I can buy back my old 5.3 that ended up being a 4.8, and it's a 2008 model, but 99-04 5.3s I get for 400-500$ all day long from parts yards so it's hard not to go the cheap replacement route.
Still trying to figure out weather to use MS or the new Holley EFI self tuning. I hear MS has self tuning software but not much detail yet.
Need to figure out the cheapest external fuel pump and of course looking for cost effective turbo capable of my needs.
Of course a 6.0 would make it easier to hit 800 mark but I hear the stock slugs are being pushed at that range.
Still trying to figure out weather to use MS or the new Holley EFI self tuning. I hear MS has self tuning software but not much detail yet.
Need to figure out the cheapest external fuel pump and of course looking for cost effective turbo capable of my needs.
Of course a 6.0 would make it easier to hit 800 mark but I hear the stock slugs are being pushed at that range.
12-18-2014, 12:14 PM
#7
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Mine is a 80k mile gen 3 engine with gen 4 rods/pistons. My stock top ring was at 18 and with the new rings I gapped them to 24. I've pushed mine to 23 psi with that set up and plan on pushing it a bit more.
The newer version of the MS has the auto correct for the fueling like the Holley. The big difference between them is the speed of the correcting by the MS isn't as fast as the Holley.
The newer version of the MS has the auto correct for the fueling like the Holley. The big difference between them is the speed of the correcting by the MS isn't as fast as the Holley.
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12-18-2014, 12:51 PM
#8
I'm stuck on what direction to go. I can buy back my old 5.3 that ended up being a 4.8, and it's a 2008 model, but 99-04 5.3s I get for 400-500$ all day long from parts yards so it's hard not to go the cheap replacement route.
Still trying to figure out weather to use MS or the new Holley EFI self tuning. I hear MS has self tuning software but not much detail yet.
Need to figure out the cheapest external fuel pump and of course looking for cost effective turbo capable of my needs.
Of course a 6.0 would make it easier to hit 800 mark but I hear the stock slugs are being pushed at that range.
Still trying to figure out weather to use MS or the new Holley EFI self tuning. I hear MS has self tuning software but not much detail yet.
Need to figure out the cheapest external fuel pump and of course looking for cost effective turbo capable of my needs.
Of course a 6.0 would make it easier to hit 800 mark but I hear the stock slugs are being pushed at that range.
4.8 also has a better bore/stroke ratio for boost. More RPM means cheaper converters. ($450 10" PTC units work great) A 4.8 can easily make 800 hp. I was making about that at only 19lbs. Trapping 151. Could have run 25-28lbs and made well over 800 IMO.
I run an MS3. It has autotune, works great.
Any of the 75-76mm S400 line of BW turbos would be the cheapest/best route IMO.
Are you runnign E85? Magna fuel 4303 is a great single inline pump that would meet your needs.
Price VS performance the cheapest route is multple inline 255HP walbros. 2 for pump gas... 3 for E85 at 800hp levels.
12-18-2014, 02:59 PM
#9
Mine is a 80k mile gen 3 engine with gen 4 rods/pistons. My stock top ring was at 18 and with the new rings I gapped them to 24. I've pushed mine to 23 psi with that set up and plan on pushing it a bit more.
The newer version of the MS has the auto correct for the fueling like the Holley. The big difference between them is the speed of the correcting by the MS isn't as fast as the Holley.
The newer version of the MS has the auto correct for the fueling like the Holley. The big difference between them is the speed of the correcting by the MS isn't as fast as the Holley.
I'd go with the gen 4. Gen3 rods tend to be the weak link on 5.3/6.0 and get bendy around 600-700 on many setups. Some have pushed then farther.
4.8 also has a better bore/stroke ratio for boost. More RPM means cheaper converters. ($450 10" PTC units work great) A 4.8 can easily make 800 hp. I was making about that at only 19lbs. Trapping 151. Could have run 25-28lbs and made well over 800 IMO.
I run an MS3. It has autotune, works great.
Any of the 75-76mm S400 line of BW turbos would be the cheapest/best route IMO.
Are you runnign E85? Magna fuel 4303 is a great single inline pump that would meet your needs.
Price VS performance the cheapest route is multple inline 255HP walbros. 2 for pump gas... 3 for E85 at 800hp levels.
4.8 also has a better bore/stroke ratio for boost. More RPM means cheaper converters. ($450 10" PTC units work great) A 4.8 can easily make 800 hp. I was making about that at only 19lbs. Trapping 151. Could have run 25-28lbs and made well over 800 IMO.
I run an MS3. It has autotune, works great.
Any of the 75-76mm S400 line of BW turbos would be the cheapest/best route IMO.
Are you runnign E85? Magna fuel 4303 is a great single inline pump that would meet your needs.
Price VS performance the cheapest route is multple inline 255HP walbros. 2 for pump gas... 3 for E85 at 800hp levels.
What all comes with the newest MS? I think I saw a complete ECU and harness for 1100$ but could not tell if it had the connectors on it or what all needed to be done. And cheaper is better. I would only have to set timing? I'm only familiar with MSD software for timing control on my carbed engines so I am curious how user friendly MS is.
And I'll be running 93 **** water and probably throw methanol inj at it. I assume I can have it controlled with the MS or Holley to come on at XX amount of boost level?
12-18-2014, 03:20 PM
#10
There are no ring differences between Gen3/4. Rod strength/floating pistons & crank/cam teeth are the main differences.
Depending on your technical/electrical skill level a complete MS setup can be done under $400. There are many different MS boxes with all different price ranges. If you want a “plug and play” LS MS setup I’d go here. http://www.efisource.com/ They have the harness and all ready to go. You don’t set timing and an LS, you just verify/sync it with the MS… most don’t even do that. The MS3 units can easily control meth inj.
Read around a little, your questions aren’t anything new. The Gen4 4.8 will take a ton of abuse. Pump gas will be the limiting factor for an 800HP goal. You’re not going to make 800HP on pump gas without spending some money. Easiest upgrade by far is E85. If you can’t swing that, I’d look into 317 heads and thick head gaskets to get the compression down. Otherwise you’ll run into detonation well before your goal.
Depending on your technical/electrical skill level a complete MS setup can be done under $400. There are many different MS boxes with all different price ranges. If you want a “plug and play” LS MS setup I’d go here. http://www.efisource.com/ They have the harness and all ready to go. You don’t set timing and an LS, you just verify/sync it with the MS… most don’t even do that. The MS3 units can easily control meth inj.
Read around a little, your questions aren’t anything new. The Gen4 4.8 will take a ton of abuse. Pump gas will be the limiting factor for an 800HP goal. You’re not going to make 800HP on pump gas without spending some money. Easiest upgrade by far is E85. If you can’t swing that, I’d look into 317 heads and thick head gaskets to get the compression down. Otherwise you’ll run into detonation well before your goal.
12-18-2014, 05:26 PM
#11
Yea, I know I'm not treading new water, google gives me some info but some of it gets old digging through stuff and not finding the answers. "Self tuning MS" type searches didn't give me much detail. But I am liking the cash savings over the Holley setup if it works fine.
I was going for a methanol injection for sure and have some 317 heads available, but most say that giving up compression just requires more boost and the back and forth argument so I am not sure about it. Can make for a lazy boost time and all that, ect. Still may go with another 6.0 just to make it easier, but that's all depending on what I get my deal on.
I was going for a methanol injection for sure and have some 317 heads available, but most say that giving up compression just requires more boost and the back and forth argument so I am not sure about it. Can make for a lazy boost time and all that, ect. Still may go with another 6.0 just to make it easier, but that's all depending on what I get my deal on.
12-18-2014, 07:11 PM
#13
Yea, I know I'm not treading new water, google gives me some info but some of it gets old digging through stuff and not finding the answers. "Self tuning MS" type searches didn't give me much detail. But I am liking the cash savings over the Holley setup if it works fine.
I was going for a methanol injection for sure and have some 317 heads available, but most say that giving up compression just requires more boost and the back and forth argument so I am not sure about it. Can make for a lazy boost time and all that, ect. Still may go with another 6.0 just to make it easier, but that's all depending on what I get my deal on.
I was going for a methanol injection for sure and have some 317 heads available, but most say that giving up compression just requires more boost and the back and forth argument so I am not sure about it. Can make for a lazy boost time and all that, ect. Still may go with another 6.0 just to make it easier, but that's all depending on what I get my deal on.
Bought my MS3 and LS harness from a friend. It was built by a shop in canada.
12-18-2014, 08:32 PM
#14
I know the Holley kit is 1500$ right now, but I don't have that much.
Is the user interface anything like HP tuners? A friend has that and we use it to turn off VATS and all the odds and ends.
So far, I'm thinking I'll be in the build 3000$ between the electronics(Holley), a used s475, a a1000 fuel pump or comparable, and injectors. I already have a MAF and TB as well as truck intake, so it doesn't seem like I'll have to invest much. I can sell the mustang kooks LS swap headers, and I'm sure the X pipe, carbed intake, carb and ignition controller to get back a decent part of that. I have plenty of truck manifolds to use.
Is the user interface anything like HP tuners? A friend has that and we use it to turn off VATS and all the odds and ends.
So far, I'm thinking I'll be in the build 3000$ between the electronics(Holley), a used s475, a a1000 fuel pump or comparable, and injectors. I already have a MAF and TB as well as truck intake, so it doesn't seem like I'll have to invest much. I can sell the mustang kooks LS swap headers, and I'm sure the X pipe, carbed intake, carb and ignition controller to get back a decent part of that. I have plenty of truck manifolds to use.
12-19-2014, 03:44 AM
#15
You alredy got the msd spark box. Why not get the basic megasquirt v1 or 2?
Control the fuel w the ms and ignition w the 6010.
The 6010 and 6012 have a boost ignition retard that reads off map?
Seems like would b most economical. Denmah
Ran one of his builds this way iirc.
Control the fuel w the ms and ignition w the 6010.
The 6010 and 6012 have a boost ignition retard that reads off map?
Seems like would b most economical. Denmah
Ran one of his builds this way iirc.
12-24-2014, 11:32 AM
#20
The more I look the more it seems a high mileage 4.8-6.0 is what you want. 200k miles or so and let it eat with a cam swap.
Going to be fun. A 6.0 will make it easier, but the 4.8 and 5.3 thicker bore enjoy the abuse.
Thanks for the info guys, income tax will get the ball rolling unless I sell my s10 and don't replace it with a 4th gen daily.
Going to be fun. A 6.0 will make it easier, but the 4.8 and 5.3 thicker bore enjoy the abuse.
Thanks for the info guys, income tax will get the ball rolling unless I sell my s10 and don't replace it with a 4th gen daily.