dq

Jeremy · 03-30-2008, 08:29 PM

Cam lift checked .010 safe side with my check lifter during the inspection but Bruce would only accept an NHRA lifter. They used a big block Mopar lifter which is different push rod seat which caused an increase. By the time I figured out what was going down I was gone.

5 cc's of the port volume was because of the change from the stock tulip valve to a cut down Manley nail head valve and some more for the new any valve job.

Thanks
Jerry

Chad Rhodes · 03-30-2008, 08:43 PM

Quote:

Originally Posted by Jeremy

Cam lift checked .010 safe side with my check lifter during the inspection but Bruce would only accept an NHRA lifter. They used a big block Mopar lifter which is different push rod seat which caused an increase. By the time I figured out what was going down I was gone.

5 cc's of the port volume was because of the change from the stock tulip valve to a cut down Manley nail head valve and some more for the new any valve job.

Thanks
Jerry

how could a different pushrod seat make it move further? changed the rocker geometry i guess?

Alan Roehrich · 03-30-2008, 09:04 PM

The location of the pushrod seat directly effects the effective length of the pushrod. Now, a rocker arm is NOT constant ratio. The ratio of a rocker arm changes constantly as the ends rotate around the fulcrum. Raising or lowering the pushrod seat raises or lowers the pushrod, changing the effective ratio of the rocker at various points.

Larry Hill · 03-30-2008, 09:04 PM

If the lifter seat is and or the lifter is taller than the one used, the adjustment screw moves closer to the fulcrum changing the lift at the valve.
On head runner cc there is no rule in stock.

Alan Roehrich · 03-30-2008, 09:07 PM

I was told by 3-4 NHRA tech guys that they are pouring Stock heads at random, and collecting data to make a database.

Jeremy · 03-30-2008, 09:22 PM

Lifter push rods angle on a small Mopar and the Hemi's are very bad. If the correct lifter (with lots of clearance around the push rod)is not used the pushrod will hit the side of the push rod seat and cause the push rod to raise off of it's seat which will increase the lift.

Jeremy · 03-30-2008, 09:53 PM

Also: I cleaned the combustion chamber I was told to and they checked the dirty one next to it. Found out they use the common rounded off stroke number instead of the one that's carried out to the thousands, luckly I had pleanty of safety on both.

bill dedman · 03-31-2008, 12:11 AM

So, Jerry, are you going to appeal this on the basis of 1. the wrong lifter being used to check valve lift, and 2. no Stock runner cc's (port volume numbers) to adhere to?
Sounds like you'd have a pretty good case to me. But, what do I know?????????????

03-30-2008, 08:29 PM	#1
Jeremy Junior Member Join Date: Dec 2002 Posts: 95 Likes: 0 Liked 1 Time in 1 Post	Re: dq Cam lift checked .010 safe side with my check lifter during the inspection but Bruce would only accept an NHRA lifter. They used a big block Mopar lifter which is different push rod seat which caused an increase. By the time I figured out what was going down I was gone. 5 cc's of the port volume was because of the change from the stock tulip valve to a cut down Manley nail head valve and some more for the new any valve job. Thanks Jerry

03-30-2008, 09:04 PM	#3
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,125 Likes: 1,583 Liked 1,880 Times in 422 Posts	Re: dq The location of the pushrod seat directly effects the effective length of the pushrod. Now, a rocker arm is NOT constant ratio. The ratio of a rocker arm changes constantly as the ends rotate around the fulcrum. Raising or lowering the pushrod seat raises or lowers the pushrod, changing the effective ratio of the rocker at various points. __________________ Alan Roehrich 212A G/S

03-30-2008, 09:04 PM	#4
Larry Hill Live Reporter Join Date: Oct 2004 Location: Hickory, Ky Posts: 10,663 Likes: 1,954 Liked 10,830 Times in 2,251 Posts	Re: dq If the lifter seat is and or the lifter is taller than the one used, the adjustment screw moves closer to the fulcrum changing the lift at the valve. On head runner cc there is no rule in stock. __________________ IHM Used Parts https://ihmusedparts.com 888-821-1817

03-30-2008, 09:07 PM	#5
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,125 Likes: 1,583 Liked 1,880 Times in 422 Posts	Re: dq I was told by 3-4 NHRA tech guys that they are pouring Stock heads at random, and collecting data to make a database. __________________ Alan Roehrich 212A G/S

03-30-2008, 09:22 PM	#6
Jeremy Junior Member Join Date: Dec 2002 Posts: 95 Likes: 0 Liked 1 Time in 1 Post	Re: dq Lifter push rods angle on a small Mopar and the Hemi's are very bad. If the correct lifter (with lots of clearance around the push rod)is not used the pushrod will hit the side of the push rod seat and cause the push rod to raise off of it's seat which will increase the lift.

03-30-2008, 09:53 PM	#7
Jeremy Junior Member Join Date: Dec 2002 Posts: 95 Likes: 0 Liked 1 Time in 1 Post	Re: dq Also: I cleaned the combustion chamber I was told to and they checked the dirty one next to it. Found out they use the common rounded off stroke number instead of the one that's carried out to the thousands, luckly I had pleanty of safety on both.

03-31-2008, 12:11 AM	#8
bill dedman VIP Member Join Date: Feb 2002 Location: Conway, AR Posts: 1,739 Likes: 0 Liked 6 Times in 4 Posts	Re: dq So, Jerry, are you going to appeal this on the basis of 1. the wrong lifter being used to check valve lift, and 2. no Stock runner cc's (port volume numbers) to adhere to? Sounds like you'd have a pretty good case to me. But, what do I know????????????? __________________ Bill

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