My old school 340 upgrades and results.

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Nice tool to have on hand. Glad to hear the good news.
 

340dartley said:
That would be cool but I would be happy with an 11.99 lol
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If it goes 11.2 then I will have to start getting the roll bar or cage up to par. Seat belts will have to be replaced also. Not sure what else. If I am 11.50 or slower I am ok.
 
As funds allow I will upgrade . Would feel good to eventually run 10s. Will need more motor and car though. Maybe a 150 shot of nitrous but jk
 
New parts show up in the mail today. Can't wait to get them installed.

20160511_132343.jpg
 
Double springs that are not broken are a pain in the *** to get off. Any ideas with the heads still bolted on. Also found a slightly bent pushrod today.
 
Don't think I bent a valve. No air leaking when pressurized with air . Also while searching my treasures aka old boxes of junk I have collected I found a new set of intake gaskets for a magnum. I placed them on my Performer RPM that is scheduled to go on and the ports and holes all line up. No provision for exhaust cross over which I would be blocking off anyway.
 
For the record i got 4 springs swapped out. The problem is my spring compressor obly hooks on the outer spring. I have to over come the inner spring by manually pushing it down while trying to fish the keepers out with a magnet. Kind of wish i had just found 3 inner springs and just swapped them out.
I will take my 273 rocker arms and pushrods to work tomorrow so I can get them cleaned up. These new springs are stiff and I just don't see the pushrods and or rockers living that long. I my fire it with the stamped rockers if I don't have the others ready in time.
 
340dartley said:
Already planned on it. The rec installed height is slightly off from what I am using. They rec. 1.8. The valve I measured was 1.735.
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Spring installed height is 1.80.....and you are setting them at 1.735?.......How much lift does the cam have...and at what height does the spring go into coil bind?
 
Ok thanks for pointing this out. I just relooked this special up. I may have made an error. Advertised lift is .508. Coil bind is listed at 1.167. I just went and physically measured one of the springs at coil bind. I measured 1.145. If I have 1.735 installed height then I think I am ok. If my installed height is 1.6ish then I am in trouble. What I have measured so far is exhaust of number 1 is 1.7 intake 1.73 number 3 intake 1.7 and exhaust 1.735. 1.7 is tighter than I want to see. My calculations puts me at .045 coil bind clearance. I would prefer to see .060 to .080. I may be removing heads to correct installed height . It seems to be never ending lol
 
One other thought I just had I should measure the lift at the valve. If the rocker arms are not true 1.5 to 1 then I may not be opening the valve a true .508. Can I do this with the rockers that are on there or do I need a solid lifter?
 
What you would need is a better rocker arm. Crane has excellent mechanical rockers or step up to a roller rocker.

You do not need a solid lifter but to only check the lift. One lifter and one pushrod at the correct length.
 
rumblefish360 said:
What you would need is a better rocker arm. Crane has excellent mechanical rockers or step up to a roller rocker.

You do not need a solid lifter but to only check the lift. One lifter and one pushrod at the correct length.
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Why do I need a better rocker? The way things are looking I would be better off if my rockers come in at 1.45 ratio. I would like to know true lift at the valve. I have read we lose about .010 in lift at the valve due to lifter to pushrod alignment. That coupled with 1.45 ratio rocker arms may get me my clearance from coil bind. I don't want to just go on what I have read. Would like to measure myself so I can sleep at night.
 
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Nice detective work,Dartley. Kudos to all that helped him,get it right.
 
Why not run a spring with the factory installed height of 1.68-1.70, then shim them up? By the measurement of your installed height it sounds like they are stock length. Here is my home made spring compressor made from an old stamped rocker with a pipe welded on, worked good on my dual spring.

tool.JPG
 
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gtsdude said:
Why not run a spring with the factory installed height of 1.68-1.70, then shim them up? By the measurement of your installed height it sounds like they are stock length. Here is my home made spring compressor made from an old stamped rocker with a pipe welded on, worked good on my dual spring.

View attachment 1714933815
Click to expand...
Slick looking spring compressor. As to why I didn't go with different springs, I couldn't find any with the pressures and travel I wanted that fit in the installed height that I had in my price range. When I went with these I my have made a miscalculation but I had looked at so many springs they all started to blend together.
 
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