Max lift and duration with a stock head & piston
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On The Tree
Joined: May 2002
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From: Richmond, Virginia
Max lift and duration with a stock head & piston I had posted the topic of what the max lift would be with a stock head and piston in the LS1 and was correctly told that not just the lift, but also the duration and setting of the cam as to the intake valve CL at TDC taking advance or retard into affect.
Assuming a stock head and piston, does anyone have a rough idea as to the max duration and max lift with the cam installed straight up would be.
This would help..... People who have installed some of the cams should know whether in their instance if piston to valve clearance became an issue...
Thanks again to all who have responded and to all who will respond to this modified question.
Assuming a stock head and piston, does anyone have a rough idea as to the max duration and max lift with the cam installed straight up would be.
This would help..... People who have installed some of the cams should know whether in their instance if piston to valve clearance became an issue...
Thanks again to all who have responded and to all who will respond to this modified question.
Joined: Nov 2001
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From: Cecil County Raceway!!!
Re: Max lift and duration with a stock head & piston I believe thunders new 230/224 cam is pushing the envelope...True PV clearance has yet to be measured with it though
Most any cam out there on the market will work with stock heads without worry of PV clearance.
I'd be concerned when you start exceeding 230 duration on the intake side.
Most any cam out there on the market will work with stock heads without worry of PV clearance.
I'd be concerned when you start exceeding 230 duration on the intake side.
Thread Starter
On The Tree
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From: Richmond, Virginia
Re: Max lift and duration with a stock head & piston Thanks Fireball for giving your much needed advice. I am sure that I and others appreciate it very much.. as it should keep our LS1's up and running rather than down and damaged.
Again... thanks...
Again... thanks...
Thread Starter
On The Tree
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From: Richmond, Virginia
Re: Max lift and duration with a stock head & piston Good Luck with your changes.... Please let us know how much you had to fly cut, and if only for the intake or did you have to do both. Or was there enough PV Clearance with the milled heads and the 232 Cam.......
Thanks again...
Thanks again...
Re: Max lift and duration with a stock head & piston </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fireball:
<strong> FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Don't you have to wait until fall? Isn't that the start of Moose hunting season? <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<strong> FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Don't you have to wait until fall? Isn't that the start of Moose hunting season? <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Joined: Nov 2001
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From: Cecil County Raceway!!!
Re: Max lift and duration with a stock head & piston edit...after reading my reply..it may be a bit unclear...the 230/224 is FINE with stock heads...but its starting to get close (at least
Thunder thinks so) so they are planning on measuring it since it pertains to what happens if the heads are milled <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Thunder thinks so) so they are planning on measuring it since it pertains to what happens if the heads are milled <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Thread Starter
On The Tree
Joined: May 2002
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From: Richmond, Virginia
Re: Max lift and duration with a stock head & piston Thanks again Fireball.... for clearing that up.
If the 230 is getting close but OK with stock heads.... how about when heads are changed to say one of the aftermarket stage 1,2,3 heads. Do they retain a stock valve to piston clearance.. or are they more like a head that has been slightly milled?
Thanks for your help.. it is enlightening and has given me a direction to pursue for my future cam.
If the 230 is getting close but OK with stock heads.... how about when heads are changed to say one of the aftermarket stage 1,2,3 heads. Do they retain a stock valve to piston clearance.. or are they more like a head that has been slightly milled?
Thanks for your help.. it is enlightening and has given me a direction to pursue for my future cam.
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From: Cecil County Raceway!!!
Re: Max lift and duration with a stock head & piston </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Jadeeglide1550:
<strong>Thanks again Fireball.... for clearing that up.
If the 230 is getting close but OK with stock heads.... how about when heads are changed to say one of the aftermarket stage 1,2,3 heads. Do they retain a stock valve to piston clearance.. or are they more like a head that has been slightly milled?
Thanks for your help.. it is enlightening and has given me a direction to pursue for my future cam.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thats where the concern lies. They are working on getting it measured soon. There are 2 factors to be concerned about with aftermarket heads:
1) bigger valves (puts the edge closer to the pistons)
2) milled bottoms (puts the valves closer to the pistons)
FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. I'm 99.9% sure my new setup will have some PV clearance issues on the intake side so I bought the isky flycutting tool to make some man-made reliefs <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<strong>Thanks again Fireball.... for clearing that up.
If the 230 is getting close but OK with stock heads.... how about when heads are changed to say one of the aftermarket stage 1,2,3 heads. Do they retain a stock valve to piston clearance.. or are they more like a head that has been slightly milled?
Thanks for your help.. it is enlightening and has given me a direction to pursue for my future cam.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thats where the concern lies. They are working on getting it measured soon. There are 2 factors to be concerned about with aftermarket heads:
1) bigger valves (puts the edge closer to the pistons)
2) milled bottoms (puts the valves closer to the pistons)
FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. I'm 99.9% sure my new setup will have some PV clearance issues on the intake side so I bought the isky flycutting tool to make some man-made reliefs <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
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Re: Max lift and duration with a stock head & piston </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ragtop 99:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fireball:
<strong> FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Don't you have to wait until fall? Isn't that the start of Moose hunting season? <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">LOL thats funny stuff. he must be poching.lol
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fireball:
<strong> FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Don't you have to wait until fall? Isn't that the start of Moose hunting season? <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">LOL thats funny stuff. he must be poching.lol
TECH Apprentice
Joined: Jan 2002
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From: Dallas, TX
Re: Max lift and duration with a stock head & piston I am very interested in this as well, considering that I am in the process of ordering a new cam while I am rebuilding my motor.....
Just to through this out there since it was said that the TR 230/224 cam was pushing the envelope on P/V clearance. What about the new MTI X1 cam, it is also a 230 duration cam, but with .591 lift on the intake side, with S2 heads as well, which I would assume are milled slightly........
Any thoughts on that.......
Just to through this out there since it was said that the TR 230/224 cam was pushing the envelope on P/V clearance. What about the new MTI X1 cam, it is also a 230 duration cam, but with .591 lift on the intake side, with S2 heads as well, which I would assume are milled slightly........
Any thoughts on that.......
Re: Max lift and duration with a stock head & piston </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fireball:
Thats where the concern lies. They are working on getting it measured soon. There are 2 factors to be concerned about with aftermarket heads:
1) bigger valves (puts the edge closer to the pistons)
2) milled bottoms (puts the valves closer to the pistons)
FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. I'm 99.9% sure my new setup will have some PV clearance issues on the intake side so I bought the isky flycutting tool to make some man-made reliefs <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> [/QB]</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The milling is MUCH bigger of an issue than the larger valves. This is because milling is a direct amount putting the valves closer to the pistons whereas the increase in valve size only minimally reduces the clearance.
Since the valves are at a 15 degree angle and you are increasing valve size 0.010 per side of each valve, sin15*(0.010") = 0.00259" decrease in clearance vs. the 0.040" decrease in clearance due to the milling, all things being equal.
Thats where the concern lies. They are working on getting it measured soon. There are 2 factors to be concerned about with aftermarket heads:
1) bigger valves (puts the edge closer to the pistons)
2) milled bottoms (puts the valves closer to the pistons)
FWIW I'm going 232/232 .574/.574 112 with 5.3 heads milled .040 and 2.02 intake valves. I'm 99.9% sure my new setup will have some PV clearance issues on the intake side so I bought the isky flycutting tool to make some man-made reliefs <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> [/QB]</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The milling is MUCH bigger of an issue than the larger valves. This is because milling is a direct amount putting the valves closer to the pistons whereas the increase in valve size only minimally reduces the clearance.
Since the valves are at a 15 degree angle and you are increasing valve size 0.010 per side of each valve, sin15*(0.010") = 0.00259" decrease in clearance vs. the 0.040" decrease in clearance due to the milling, all things being equal.
I can shift faster than you.
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From: Baton Rouge, LA
Re: Max lift and duration with a stock head & piston </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by LIL SS:
<strong>Any new updates?? Has Thunder checked the clearences?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The results were posted here:
https://ls1tech.com/ubb/cgi-bin/ulti...c;f=1;t=005477
<strong>Any new updates?? Has Thunder checked the clearences?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The results were posted here:
https://ls1tech.com/ubb/cgi-bin/ulti...c;f=1;t=005477
