Am I crazy for turning this kind of rpm? And timing?
#1
Am I crazy for turning this kind of rpm? And timing?
I have a couple questions for you experienced forced induction fellas. First off, it’s a 2004 ls1 gto. I’m wondering if it’s a gen 4 rod engine? It had the 13mm bolts on the exhaust manifolds and valley cover if that makes any difference.
What I have is a 227/234 Brian tooley stage 2 cam, non turbo version. 113 lobe separation. The heads are ported 243’s, quench is about .039 and the combustion chambers were smoothed and polished. I’m running 17-18 degrees timing st 6-7psi boost right now. My afr was 10.8 so it’s a little rich. It never had knock at 27-28 degrees timing when it was n/a. So do you guys think I need to turn the timing down?
Also, I’m shifting it at 7000rpm. Am I playing with fire? Should I lower it a tad? This motor won’t be in here for a whole lot longer but I can’t blow it up betim giving it to my son and building a boost friendly 5.3
whats your take on this? Thanks in advance fellas.
What I have is a 227/234 Brian tooley stage 2 cam, non turbo version. 113 lobe separation. The heads are ported 243’s, quench is about .039 and the combustion chambers were smoothed and polished. I’m running 17-18 degrees timing st 6-7psi boost right now. My afr was 10.8 so it’s a little rich. It never had knock at 27-28 degrees timing when it was n/a. So do you guys think I need to turn the timing down?
Also, I’m shifting it at 7000rpm. Am I playing with fire? Should I lower it a tad? This motor won’t be in here for a whole lot longer but I can’t blow it up betim giving it to my son and building a boost friendly 5.3
whats your take on this? Thanks in advance fellas.
#4
Can't really say you're crazy for the rpm, but personally I'm not a fan of buzzing a street motor as it's hard on parts...namely valvesprings. Many around here do it though, but they are what I would call racecars, with no real expectation of longevity.
#5
93. No meth right now. I’m running low boost. I won’t be putting it on e85 either because we only have one pump here in town. This isn’t a max effort car by any means. My goal is about 550-600rwhp reliably. I’m on 6lbs right now and I may not need to go any higher than 8psi. It honestly feels like at least 125 shot of nitrous. I happy with how it currently runs and it’s not even dialed in yet.
#7
TECH Veteran
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If you have stock pushrods, they are already bent. If you upgraded, spin it and enjoy. As to your last question, 200 rpm ain't nothing until it all of a sudden is. Energy goes up as the square of velocity, so at some point that last little bit makes a huge difference. With aftermarket cam and springs, at a certain point you have to worry about the stock lifters. You may not be there yet, but keep it in the back of your mind.
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#8
If you have stock pushrods, they are already bent. If you upgraded, spin it and enjoy. As to your last question, 200 rpm ain't nothing until it all of a sudden is. Energy goes up as the square of velocity, so at some point that last little bit makes a huge difference. With aftermarket cam and springs, at a certain point you have to worry about the stock lifters. You may not be there yet, but keep it in the back of your mind.
#9
Mines a gen 4 SBE 6.0 . When it was N/A, I hit 7 k on the reg all the time. But, I put 3/8 pushrods in when I did the cam . Springs went in about 10k. Just wouldn’t hit 7 k anymore. Put BTR duals in, now it’s fine. Now that it’s supercharged, doesn’t really need to hit 7 k anymore. Just going thru the traps @ top of 3rd
#10
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I used to spin my 04 LS1 to 6800 every time i drove it. Man that motor was awesome. It was always just NA though.
Here's a vid with a gopro, motor sounds great at that rpm.
Here's a vid with a gopro, motor sounds great at that rpm.
#12
Well before it was boosted I was turning it 7000-7100 on the regular and I didn’t worry about it. Now that it’s got probably another 150fwhp I do worry about it. It’s likely over 500 at the tire. Before it was maybe 390-400ish. 4000lbs trapping 113mph and my injector duty cycle actually estimates it to be 430-440rwhp. So I’d rather estimate lower. If anyone cares to watch, I shifted around 6900, does it look like it was still pulling when I shifted or maybe it dropped off? My afr was 10.8 on this run. Just 6psi.
#14
I used to spin my 04 LS1 to 6800 every time i drove it. Man that motor was awesome. It was always just NA though.
Here's a vid with a gopro, motor sounds great at that rpm.
https://www.youtube.com/watch?v=QebpMH3HwVc&t=94s
Here's a vid with a gopro, motor sounds great at that rpm.
https://www.youtube.com/watch?v=QebpMH3HwVc&t=94s
runs good. What it run?
#18
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Well before it was boosted I was turning it 7000-7100 on the regular and I didn’t worry about it. Now that it’s got probably another 150fwhp I do worry about it. It’s likely over 500 at the tire. Before it was maybe 390-400ish. 4000lbs trapping 113mph and my injector duty cycle actually estimates it to be 430-440rwhp. So I’d rather estimate lower. If anyone cares to watch, I shifted around 6900, does it look like it was still pulling when I shifted or maybe it dropped off? My afr was 10.8 on this run. Just 6psi.
https://youtu.be/xiYeZOONbPA
https://youtu.be/xiYeZOONbPA
#20
And this is what prevents blower cars from being solid performers . Man I had to.