690 FWHP DLRE, MMS, Cam Motion, LLR, FAST 102 W MID LENGTH RUNNERS
08-15-2017, 11:35 AM
#62
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08-15-2017, 05:03 PM
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08-15-2017, 06:00 PM
#67
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08-15-2017, 06:24 PM
#69
Our LS3 loves a 239/251 110+2 hydraulic. Very similar valve events with more lift. It'd rip. I think advancing it a little more would be beneficial..maybe +4.
I think there's a lot of untapped potential still with the short runner intakes to really get after it with overlap. My latest bad idea is 243/254 110+3 or 4 in my 402. Pretty much the same except a little bigger for the 4" stroke.
I think there's a lot of untapped potential still with the short runner intakes to really get after it with overlap. My latest bad idea is 243/254 110+3 or 4 in my 402. Pretty much the same except a little bigger for the 4" stroke.
08-15-2017, 07:36 PM
#70
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The reason not to advance further is to move the power peak to the right. If you look at valve events, it moved two degrees later IVC. But it's solid, so it'll be 2.5-3 degrees earlier after warming up. So 46.5-47 ABDC warm. Peak HP around 7200
08-16-2017, 08:35 AM
#73
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Done and Done!
That's why the bigger duration. 239 on a 108 ICL opens the intake at 11.5 BTDC and closes it at 47.5 ABDC. Advancing the cam will bring the peak power tot he left. Torque comes in sooner, peaks earlier. By doing a 245 duration on a 107 ICL, Intake valve opens at 15.5 BTDC and closes at 49.5 ABDC. Later IVC supports higher RPM, and earlier IVO to help support higher RPM breathing.
It'll want to buck a little more. Sometimes you can correct that by pulling out timing in the low load / low RPM cells where it bucks.
It'll want to buck a little more. Sometimes you can correct that by pulling out timing in the low load / low RPM cells where it bucks.
08-16-2017, 11:37 PM
#74
Yeap Darth's my cam guy also helped me out while driving.
Wanted more but not enough compression = Darth saying: I agree. Might even hurt some. I'll just do what I'm told. I'll confirm what we came up with and try to make a purchase.
Wanted more but not enough compression = Darth saying: I agree. Might even hurt some. I'll just do what I'm told. I'll confirm what we came up with and try to make a purchase.
Last edited by Patron; 08-16-2017 at 11:43 PM.
09-09-2017, 05:32 PM
#76
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Our LS3 loves a 239/251 110+2 hydraulic. Very similar valve events with more lift. It'd rip. I think advancing it a little more would be beneficial..maybe +4.
I think there's a lot of untapped potential still with the short runner intakes to really get after it with overlap. My latest bad idea is 243/254 110+3 or 4 in my 402. Pretty much the same except a little bigger for the 4" stroke.
I think there's a lot of untapped potential still with the short runner intakes to really get after it with overlap. My latest bad idea is 243/254 110+3 or 4 in my 402. Pretty much the same except a little bigger for the 4" stroke.
Do you have the SPS Haymaker Heads yet?
With those Heads in your RX7 I would
Go 243*/252* 112*+3* with your
Mid Runner would run really well
From Off Idle to 7200+ RPM.
Daniel
(lol)
09-19-2017, 05:00 PM
#77
Oh hey..not yet. Delays after delays. I'm not a big sponsored build so it keeps getting pushed aside. They're really very nearly done. One of my heads was just a display piece at LSFest so that's cool I guess. I'm being accommodating since I'm still daily driving my rx7 while working on my other car. I'm not quite able to start the project yet anyway or I'd be raising hell.
You're really close to what I was thinking. Last cam I saved in the calculator was 243/254 110+4, int 15.5 open 47.5 close, exh 61 open 13 close.
47.5 was my target intake closing as it gets ~ 8.25 dynamic compression with 11.6:1 static to hopefully be 91 octane friendly.
I wanted to open the intake at least 14* BTDC to try and best utilize the intake manifold, and keep the exhaust valve opening later than 63*. My only worry is the exhaust choking out at high rpm, but the exhaust ports flow like a mother on the SPS heads and there has to be a compromise somewhere or the cam will just keep getting bigger lol.
You're really close to what I was thinking. Last cam I saved in the calculator was 243/254 110+4, int 15.5 open 47.5 close, exh 61 open 13 close.
47.5 was my target intake closing as it gets ~ 8.25 dynamic compression with 11.6:1 static to hopefully be 91 octane friendly.
I wanted to open the intake at least 14* BTDC to try and best utilize the intake manifold, and keep the exhaust valve opening later than 63*. My only worry is the exhaust choking out at high rpm, but the exhaust ports flow like a mother on the SPS heads and there has to be a compromise somewhere or the cam will just keep getting bigger lol.
