Boosted ring gaps
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Boosted ring gaps Ok, The LQ4 is at the machine shop finally. So I wanted to get good advise on ring gaps. Its a SBE "right now anyway " unless they find they have to bore it. Since I am new to turbos I am not sure what all info is needed to make the number accurate or there is just a standard gap to set them at.
Plan to run between 6-700 rwhp most of the time.
Thanks for the input. I did search this as well, but found different things.
Plan to run between 6-700 rwhp most of the time.
Thanks for the input. I did search this as well, but found different things.
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Theres my point. LOL. Another thread stated .26 to .28 on the top and .30 on second ring. So I am hoping to get some good info here. So this makes 2 opinions so far.
This was Texas speed recommendations when I bought all my parts from them and had my local machine shop do all the machining. So that's why I chose those specs instead of the 10 different sizes you get on tech. lol
I normally recommend .024 to .028 top ring gap depending on cylinder wear and piston alloy (stock/hyper,4032,2618). Then set second ring gap .002 larger than top gap.
If you go larger only you will know, if you go tight and they butt everyone will know when they come out.
If you go larger only you will know, if you go tight and they butt everyone will know when they come out.
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If the engine is at a machine shop, why wouldn't you let them make the call? If they don't know what to do and you have to ask on a forum, the engine should not be there anyway. Just my .02
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1st because they may not build the shortblock. I might build it.
2nd even if they do, I myself want to be sure its correct. This shop builds a lot of race engines including blown setups, but not turbo setups. And they are fairly new with the LS based engines but they have built them. When the owner says he will build the short block and tells me what he is going to set the gap at, I need to know its right and not just agree with him because he is a builder.
2nd even if they do, I myself want to be sure its correct. This shop builds a lot of race engines including blown setups, but not turbo setups. And they are fairly new with the LS based engines but they have built them. When the owner says he will build the short block and tells me what he is going to set the gap at, I need to know its right and not just agree with him because he is a builder.
Did one person have a failure and the other didn't? Id be more focused on peoples results. I have tried a few different ring gaps on SBE 6.0s. All have seen over 20psi and a few are over 150 in the 1/4. Never had a ring/piston failure. So id advise that the is likely a range that will work and peoples own testing/experience makes the call. Hence why you see many opinions.
With the factory stuff it depends a lot on piston temps. Which will vary with the tune, the fuel you run, water/meth injection, boost amount…etc.
.022/.024 is usually my go to and around what most high mileage motors are anyway. I wouldn’t want much tighter than that. I’ve seen some of my motors with a random cylinder as tight as .016 on top. I’ve never butted a ring, but I run E85 with water/meth and an intercooler. Pump gas builds I’d go another .002-.004 depending on the boost amount.
.022/.024 is usually my go to and around what most high mileage motors are anyway. I wouldn’t want much tighter than that. I’ve seen some of my motors with a random cylinder as tight as .016 on top. I’ve never butted a ring, but I run E85 with water/meth and an intercooler. Pump gas builds I’d go another .002-.004 depending on the boost amount.
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Did one person have a failure and the other didn't? Id be more focused on peoples results. I have tried a few different ring gaps on SBE 6.0s. All have seen over 20psi and a few are over 150 in the 1/4. Never had a ring/piston failure. So id advise that the is likely a range that will work and peoples own testing/experience makes the call. Hence why you see many opinions.
As for my setup.
SBE, S482 turbo running about 7-9 and maybe up to 13 psi street trim. I want to be around my hp numbers, so whatever that takes. And turn it up at the track. I do not know what this number will be, but I am shooting for 900 to 1000 rwhp at the track.
A2W IC, pump gas on street with a dedicated fuel cell for race fuel at the track. I will run meth injection if it needs it. I wont know until its complete and start testing.
I am going to try and have 2 base tunes so its easy to switch over to track mode. I am new to tunes as well as turbo setups so I am learning as I go. But I will learn it quickly once I lay my hands on it.
I do understand my question is a loaded gun so to speak. Everyone has their own ideas of what works. But again, I am looking for people that have actually done what I am doing. same engine, SBE, psi ect. I trust this more than what some book says you should run. And there are guys on here that have a lot of experience with this stuff. I can weed out most of the BS posts. LOL. Even after I get a number, I will research it before doing it just to verify.
I appreciate all the help I get, believe me. I do prefer actual experience over book smart any day.
800-1000 is big power in my book for any SBE build. Since you’re not going with an alcohol based fuel, your pistons will be hotter than they would be with something like E85. I’d go on the safe side and run .026/.028 on something like that.
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Yea, I know, but I cant help myself. LOL. I want to get on that list, but with real numbers, not a dyno queen. And this is the reason why I am going A2W and also meth injection if needed. I want to keep it as cool as possible without going to alcohol. Since its going to be street driven, I don't want to have to use a huge fuel cell and be stopping all the time for fuel. Its already going to be bad enough with just a 10 gallon cell that I have now. I may also put a vacuum pump on it too since I have one already. Just needs to be rebuilt. This will help free up some hp.
Taxman20... After rereading this thread with Forcefed86 chiming in on the stock piston VS forged. I have forged Mahle pistons with Total seal rings gaped to the spec's in my first post.
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It really looks like its going to be .26-.28 no matter what piston I run with. If forged pistons can be a tighter gap, I would rather run a little larger gap if it doesn't hurt anything just for safety sake.
This truck might see the track and higher psi 2-3 times a year most likely.
This truck might see the track and higher psi 2-3 times a year most likely.
When he started racing, the 392 hemi engines were really nearly stock (no aftermarket crankshafts, rods, etc even existed at that time)
He was noted for having engines that smoked bad on startup, and ran much larger bearing clearance than any of his competitors.
Cliff notes version: "If your engine clearances are too loose, only you will know, if they are too tight, everyone will know"
I suggest you make all the ring end gaps at least .030" and tell everybody they are .020
He was noted for having engines that smoked bad on startup, and ran much larger bearing clearance than any of his competitors.
Cliff notes version: "If your engine clearances are too loose, only you will know, if they are too tight, everyone will know"
I suggest you make all the ring end gaps at least .030" and tell everybody they are .020