Stop in for a cup of coffee

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114° is good for lobe separation on a street engine...

The larger the lobe separation, the less overlap and more cylinder pressure (good for lower compression engines)... Lower lobe separation (110°, 108° etc) gives more overlap and less cylinder pressure (good for higher compression or high RPM engines)....

Lobe separation is how many degrees between max intake and max exhaust lobe lifts.... Or how many degrees between intake lobe center line and exhaust lobe center line...

Lobe separation directly affects overlap... If they don't specify overlap, you can calculate it using both lobe center lines, or using intake center line and lobe separation..
I never quite understood LC and IC and why both measurements are needed.
 
Friday Fish fry is still alive and well here in WI. I prefer perch or blue gill if they have it.

It might be halibut soup here for dinner. Good to hear they still have the Friday fish fry there.

Yesterday was bread baking day for me.

Bill

Brød-17-okt-2019.jpg
 
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I never quite understood LC and IC and why both measurements are needed.

Intake center line is where you usually degree the cam to and is where the intake lobe center is.... You can also calculate it using the intake open and intake close numbers...

Lobe separation is where the exhaust center line is from the intake lobe center line... If they don't give it, you can calculate it from intake lobe center line and lobe separation angle... Or calculate the exhaust lobe center line using the exhaust open and exhaust close numbers....

Very few manufacturers give overlap numbers, Chrysler is one of the few that does... However I like to look at overlap as it gives an idea of how much duration both valves are open which affects idle vacuum... The larger the overlap, the lower the cylinder pressure and lower the intake vacuum...

Intake closing also is a major factor in dynamic compression... The later the intake valve closes, the less dynamic pressure... The earlier it closes, the higher the dynamic compression.... The cylinder can't develop compression until both valves are closed when the piston is travelling upwards.... The intake valve is the last one to close...

Overlap also affects cylinder scavenging, how well the cylinder can get all of the old burnt gasses out of the cylinder to make room for the new intake charge... You can't burn the old gasses again, so cylinder scavenging is important for making power and efficiency... You want to get all of the old burnt gasses out of the cylinder to make room for the "fresh" charge to come in... Any left over burnt gasses in the cylinder is taking up room preventing you from getting new fresh air and gas in to burn for the next cycle....

Plus when the intake valve closes, it creates a pulse in the intake... This pulse can affect how the cylinder fills... If you tune the pulse correctly and it gets to the intake valve just as it opens creates a 'ram effect' which helps push the charge into the cylinder... That was the theory of the ram induction and max wedge intakes... The long ram induction manifolds were typically tuned to 2500 RPM and the short ram were typically tuned to 3500 RPM, where the max wedge intakes were typically tuned to 6500 RPM...

The pulse is determined by the mach number of the flow in the intake which is determined by the area and length of the port... If you tune the intake using that theory you can make it efficient for the RPM range that you need....
 
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Have you ever tried a Crover cam, the one with the least duration for good trottle response ?

Bill

I had Dave Crower make a custom cam for my ex's slant 6... It was around 260° duration and .490" lift... She hasn't complained about the cam yet... (but how much she knows is limited....)

Crower makes a good cam... I haven't tried them on any of my engines yet... But would not hesitate to....

Unfortunately Dave has passed away since then, but Crower Cams is still in business last I knew...

I have run Crane Cams and been happy with them...
 
I finally got an appointment for my internet cable company to hook up the new feed cable...

Those idiots keep thinking that they need to bury a new line... Every time I've called them in the last 4 weeks they keep telling me that they need to bury a new cable... It's been buried going on 4 weeks now - I've told them that for the last 4 weeks.... :mad: :BangHead:

I've tried to be patient with them, but last weekend on my birthday after getting blown off twice by supervisors/managers that were too busy when I called and were supposed to call back and didn't, I called and asked to talk to one... They had me on the phone for an hour (literally), so I unloaded on the grunt phone operator when he told me that they needed to bury a new cable and had to get permission from the village to do that... I had to scream at him and tell him that the cable is already buried, you just need to send a guy to crimp a fitting on each end and connect the damn thing!!! :mad:

This week - no connect... So I called again yesterday and demanded a time and date for a tech to come out... They finally gave me an appointment for Monday between 8 and 11 AM.... :wtf:
Didnt say which monday....
 
I had Dave Crower make a custom cam for my ex's slant 6... It was around 260° duration and .490" lift... She hasn't complained about the cam yet... (but how much she knows is limited....)

Crower makes a good cam... I haven't tried them on any of my engines yet... But would not hesitate to....

Unfortunately Dave has passed away since then, but Crower Cams is still in business last I knew...

I have run Crane Cams and been happy with them...
And Harvey is now gone. LOL Interesting story about Harvey crane. Back in the 60's when John Deere was designing a 4 and 6 cylinder diesel to replace the old "Johnny Popper". Their prototype engines would barely run. A friend of mine in the engineering department contacted Harvey and he came up with a design that worked. From what my friend said, the engineers were thinking along the lines of a square lobe. LOL
 
So, if you your mom and uncle are 3/4 German, they are only 3/8 German each ? :D

Bill

the next generation gets cut in half....

My uncle is 3/4 German and 1/4 Polish, so his contribution is 3/8 German and 1/8 Polish... My aunt is 100% Japanese, so she contributes 50% Japanese to my cousins...

That makes my cousins, 1/2 Japanese, 3/8 German and 1/8 polish...
 
the next generation gets cut in half....

My uncle is 3/4 German and 1/4 Polish, so his contribution is 3/8 German and 1/8 Polish... My aunt is 100% Japanese, so she contributes 50% Japanese to my cousins...

That makes my cousins, 1/2 Japanese, 3/8 German and 1/8 polish...
Sushi and sauerkraut for dinner
 
I had Dave Crower make a custom cam for my ex's slant 6... It was around 260° duration and .490" lift... She hasn't complained about the cam yet... (but how much she knows is limited....)

Crower makes a good cam... I haven't tried them on any of my engines yet... But would not hesitate to....

Unfortunately Dave has passed away since then, but Crower Cams is still in business last I knew...

I have run Crane Cams and been happy with them...

I see. I had a Grower cam in the 351 Windsor I had, worked sweet. Igo that after I had a Crane cam in and could not understand anything of that can untill I put a degree wheel on and found that the opening and closing time were up to 7 degrees wrong and not one single cylinder was equal. I guess you could call it a multi engine, it was tuned to whatever need the owner had. I promised myself never to touch a Crane cam again. So you see how different experiences two people can have with the same brand.

Bill
 
Sorry I missed yall this mornin. I ain't feelin good today.
 
Naw, pretty sure it's not the flu. I have none of the usual symptoms there.
 
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