Re: LS3 Carbed build
Posted: Sun Feb 02, 2020 9:37 am
"Blue" on these sheets indicate the Late Mode Plus fuel.
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It is an 8896 1050 that Mark Whitener converted to 2 circuit with some quickfuel blocks I had and quickfuel boosters. It had 85 Holley jets all 4 corners on Late Model fuel. I put 89's in it for the Q16 pulls.
i think it just proves that valve events only work in a narrow set of parameters like rpm,engine load etc.CGT wrote: ↑Sun Feb 02, 2020 9:30 am Well, been looking everything over. Cam 2 is a better cam...in this engine anyway. It's down a bit or equal to cam 1 below 6200 but is better after that. It is 10 or 15 better on average after 7000...and is smoother, more consistent up there. It appears to keep the valvetrain more stable. Same lobe families, so think about that one for a minute.
We did a few pulls on Q16, and the pull on the videos was one of those. The best pull on Q was 763hp and 560 torque, I'm not convinced at all that it has peaked yet. The best pull on the Late model plus fuel was 758hp and 550 torque. Just noticed, I have 59 pulls on this thing already
New vacuum pump seems fine, the Schumann ER oil pump system did not change the oil pressure issue in any way that I can tell...other theories are evolving So that was a bit upsetting. Probably won't be the last 500.00 I will light on fire
Biggest hp gains from the 2 day session.... the decision to turn the engine higher.
For sure. The "perfect" cam if there is such a thing, can only be for a snapshot at a time through a given range. The wider the range your operating in, the more this becomes evident. And cam position can be like that also...until you get enough of the events out of whack that it just gives up everywhere ....I think itd be pretty easy to make a solid roller better from start to finish on this this thing though, but im sure that could be humbling.steve cowan wrote: ↑Sun Feb 02, 2020 1:01 pm i think it just proves that valve events only work in a narrow set of parameters like rpm,engine load etc.
Randy brought up a good point about cam 2. Same lobe family, same lobe lift....longer duration(cam 2) should be slightly tamer...and that could be responsible for how things smoothed out some up above 7000.steve cowan wrote: ↑Sun Feb 02, 2020 1:01 pm is it possible that spring rate and cam worked in better sync at higher rpms
One advantage of mechanical distributors, the timing light will tell you exactly how far you moved the cam.
It's really what would be expected from a cam change like this was. Bigger cam and it's a little better up top but down or the same down low.steve cowan wrote: ↑Sun Feb 02, 2020 1:01 pmi think it just proves that valve events only work in a narrow set of parameters like rpm,engine load etc.CGT wrote: ↑Sun Feb 02, 2020 9:30 am Well, been looking everything over. Cam 2 is a better cam...in this engine anyway. It's down a bit or equal to cam 1 below 6200 but is better after that. It is 10 or 15 better on average after 7000...and is smoother, more consistent up there. It appears to keep the valvetrain more stable. Same lobe families, so think about that one for a minute.
We did a few pulls on Q16, and the pull on the videos was one of those. The best pull on Q was 763hp and 560 torque, I'm not convinced at all that it has peaked yet. The best pull on the Late model plus fuel was 758hp and 550 torque. Just noticed, I have 59 pulls on this thing already
New vacuum pump seems fine, the Schumann ER oil pump system did not change the oil pressure issue in any way that I can tell...other theories are evolving So that was a bit upsetting. Probably won't be the last 500.00 I will light on fire
Biggest hp gains from the 2 day session.... the decision to turn the engine higher.
valves dont only float at peak rpm.
not sure if you are using same valve springs as before?
is it possible that spring rate and cam worked in better sync at higher rpms
18726543 4-7 2-3 swapsteve cowan wrote: ↑Mon Feb 03, 2020 11:27 am firing order with tri-y headers but I can't verify a LS firing order??
Yes, GZ actually overnighted me a completely new one, upon receiving my original.steve cowan wrote: ↑Mon Feb 03, 2020 11:27 am Was wondering if your new vac pump was replaced under warranty??
This is 2 LS engines now I've tested these goofy looking try-y's against a nice set of 4-1's. Same result both times, they were better from start to finish. The other engine was 429 CI ls7. By looking at the 2, you'd swear the 4-1's would have to run better...at least up top...nope. Exhaust stuff is humbling.steve cowan wrote: ↑Mon Feb 03, 2020 11:27 am With the tri -y headers I thought there might be some overscavanging at high rpms but I don't think that's the case, I read a while back that C Elston doesn't recommend using a 4-7 swap
I bet Randy will find a way to make it peak there if that's what he wants.steve cowan wrote: ↑Mon Feb 03, 2020 11:27 am I calculated that 454 will peak around 6500 with 2.8" average CSA but Randy advised me it was a bit bigger so I think it will be close to 7000 rpm.
Using the flowz posted and guessing at the rest here is what I come up with at the valve for cam 3 but the lift would require solid roller.randy331 wrote: ↑Wed Jan 29, 2020 12:00 amIs one of them speced with flowZ ?
Here's a thread you may want to read before ordering a 3rd cam. Talk of pros n cons of using flowZ to spec cams.
viewtopic.php?f=1&t=59855
Randy