Help Needed/Couple Questions Regarding A New Setup
02-05-2014, 02:02 AM
#42
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Ok, since i found a guy who will inspect and pass my car, I'm for sure going the Super Victor/4150 TB route. I found a cam that I think will work very well. It is 236/248 .631/.631 111 LSA. Now the question is, will it clear my heads. My cam right now is 227/235 110 LSA and I have .069" intake clearance and .101 exhaust clearance. Here is something interesting that a guy posted in a thread I made over on another forum when I asked if that cam would clear: What do you guys think?
Fairly straight forward ....
Find your current cams tdc # on the ICL, multiply by the rocker ratio.
Now take the proposed new cams tdc # on the ICL, multiply by rocker ratio.
Subtract the difference between too. ......walla, new ptv number.....since you already know your current ptv.
This is just an example. .....
current 227 lobe on a 108 ICL @ tdc = 0.070" x 1.7 = 0.119".....this means your intake valve is open 0.119" at the nearest point in the revolution. ..aka; tdc.
New cam lobe 236, on a 106 ICL @ tdc = 0.089" x 1.7 = 0.151"
So.......0.119" minus 0.151" = 0.32"
So, you have 0.069" minus 0.032" = 0.037" of ptv with new 236 lobe on a 108 ICL.
Remember this ^^^^ is just an example.
You just need to find out what lobe family your current cam is and what your new one will be. Also, the same math will figure the exhaust lobe ptv too.
Fairly straight forward ....
Find your current cams tdc # on the ICL, multiply by the rocker ratio.
Now take the proposed new cams tdc # on the ICL, multiply by rocker ratio.
Subtract the difference between too. ......walla, new ptv number.....since you already know your current ptv.
This is just an example. .....
current 227 lobe on a 108 ICL @ tdc = 0.070" x 1.7 = 0.119".....this means your intake valve is open 0.119" at the nearest point in the revolution. ..aka; tdc.
New cam lobe 236, on a 106 ICL @ tdc = 0.089" x 1.7 = 0.151"
So.......0.119" minus 0.151" = 0.32"
So, you have 0.069" minus 0.032" = 0.037" of ptv with new 236 lobe on a 108 ICL.
Remember this ^^^^ is just an example.
You just need to find out what lobe family your current cam is and what your new one will be. Also, the same math will figure the exhaust lobe ptv too.
