Wonderin how high I can turn my 5.3 safely.
#31
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Went back and looked at your dyno numbers, the second time around wasnt as bad as i thought and look on par or close to it. I still think they should be peaking a little higher than that, but that could be to a couple differnt variables and i wouldnt worry about it. as long as it feels like it just keeps pulling...
#35
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I agree with most of the people on here, shift higher until you feel it doesn't help. And as for everyone that is telling you to worry about the rod bolts, thats not going to be the the part that breaks. That issue was with the early ls1's having weaker rod bolts that would stretch and wreck the bearings, but this was corrected somewhere around 98-99 or so. The valve train is the part that needs the attention, something nobody has referenced. Not sure what you are running for valvesprings, pushrods, etc, but that needs to be up to par the higher you spin it. I would feel comfortable spinning a bone stock 5.3 up to 6300, with a higher revving cam and good valve springs, hardened pushrods, and the newer style lifters, I wouldn't hesitate to spin it to 7k if it makes power there. Note, I say safe meaning safe, not meaning its going to break 50rpm higher. This are just my opinions I have formed with my experience, I ran my 5.3 stock, with a big cam, stock 6.0l, 6.0l with a tr224, along with helping a few friends set their engines up with different combos.
#36
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Jamedee
Since you run shifts at 6200rpm now try another 100rpm and test that and maybe go from there up to 6400.
You gotta remember this is a forum and like any other forum you need to take everyones post with a grain of salt. Just because people say they run a certain shift doesn't mean you should. Get it dyno tuned so you know everything is right. I just don't wanna see you try and compare to someone elses similar cam that supposedly runs for example 6700rpm shifts, then you go try it and mess your stuff up. Yeah these engines can take abuse but I would stick with a shift that YOU feel safe at.
You just gotta be careful what you read on forums sometimes. One example I see a lot on forums is a lot of guys on many forums says cam swaps on our trucks take 4 hours which is not true lol.. Maybe someone that works on LS engines every day for a living can do it in 6 hours that has the proper tools etc can do it fast but someone that is not familiar with these LS engines may take 3-4 days and you need to make sure you have all the right tools on hand.
Maybe you understand what I'm getting at different people have different experience levels. I just thought this all needed to be said.
Since you run shifts at 6200rpm now try another 100rpm and test that and maybe go from there up to 6400.
You gotta remember this is a forum and like any other forum you need to take everyones post with a grain of salt. Just because people say they run a certain shift doesn't mean you should. Get it dyno tuned so you know everything is right. I just don't wanna see you try and compare to someone elses similar cam that supposedly runs for example 6700rpm shifts, then you go try it and mess your stuff up. Yeah these engines can take abuse but I would stick with a shift that YOU feel safe at.
You just gotta be careful what you read on forums sometimes. One example I see a lot on forums is a lot of guys on many forums says cam swaps on our trucks take 4 hours which is not true lol.. Maybe someone that works on LS engines every day for a living can do it in 6 hours that has the proper tools etc can do it fast but someone that is not familiar with these LS engines may take 3-4 days and you need to make sure you have all the right tools on hand.
Maybe you understand what I'm getting at different people have different experience levels. I just thought this all needed to be said.
#37
My point is not everyone on the forum is experienced, and you see fellas on every forum giving advice to newbies telling them it will take them 4 hours to do a cam swap in our engines. It's misleading to some people.
If the person is not familiar with these LS engines and does not have the right tools at hand and does not have all the parts ready to go at the garage that time adds up fast. You gotta have all the parts at hand and not be taking several trips to your local parts store for various parts. My advice like stated is make sure you have EVERYTHING ready to go and get ALL the proper tools and no cheap valve spring tools.
I have seen guys that have built older gm small block engines and they attempt to do an LS engine cam swap (never done one before) it might take them a few hours just to do the valve springs or longer. It could be just that they are not familiar with the LS engines or have the wrong valve spring tool. Not everyone can do a cam swap in 7 hours and not everyone should run their engine at 7000rpm's is all I'm trying to say.
#39
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I agree with most of the people on here, shift higher until you feel it doesn't help. And as for everyone that is telling you to worry about the rod bolts, thats not going to be the the part that breaks. That issue was with the early ls1's having weaker rod bolts that would stretch and wreck the bearings, but this was corrected somewhere around 98-99 or so. The valve train is the part that needs the attention, something nobody has referenced. Not sure what you are running for valvesprings, pushrods, etc, but that needs to be up to par the higher you spin it. I would feel comfortable spinning a bone stock 5.3 up to 6300, with a higher revving cam and good valve springs, hardened pushrods, and the newer style lifters, I wouldn't hesitate to spin it to 7k if it makes power there. Note, I say safe meaning safe, not meaning its going to break 50rpm higher. This are just my opinions I have formed with my experience, I ran my 5.3 stock, with a big cam, stock 6.0l, 6.0l with a tr224, along with helping a few friends set their engines up with different combos.