My old school 340 upgrades and results.

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Yes I mistyped. Open pressure. 100 to 150 seat pressure.
I don't think I am overthinking it so much. Maybe a little. 1.7 installed height .508 (assuming true .508) puts me at 1.192. Coil bind advertised is 1.16. Puts me at .032 which is way to tight before coil bind. If I have a valve athe 1.68 then I am in negative territory. See why I am worried a little. Now I did measure 1.145 as true coil bind. So I gained a little back but it doesn't take much to make for a disaster. Yes I probably bought the incorrect springs. I own that.
 
340dartley said:
Yes I mistyped. Open pressure. 100 to 150 seat pressure.
I don't think I am overthinking it so much. Maybe a little. 1.7 installed height .508 (assuming true .508) puts me at 1.192. Coil bind advertised is 1.16. Puts me at .032 which is way to tight before coil bind. If I have a valve athe 1.68 then I am in negative territory. See why I am worried a little. Now I did measure 1.145 as true coil bind. So I gained a little back but it doesn't take much to make for a disaster. Yes I probably bought the incorrect springs. I own that.
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How are you measuring installed height?
 

gtsdude said:
Any +.050 valve locks available for your type of valve?
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I will check on them.

I just got the spring tension of my old vs new springs. Old springs have 180 seat pressure and 460 open. Pretty stout spring. New spring mind you it isn't broke in , comes in at 210 seat pressure and 510 open. Good news is broken in it will be very close to the other spring. Bad news is both seem too high.
 
Sounds like a different spring would be a better way to go, if you need shims let me know, I can send some your way, I bought way too many when I set up my X heads.
 
gtsdude said:
Sounds like a different spring would be a better way to go, if you need shims let me know, I can send some your way, I bought way too many when I set up my X heads.
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The old springs were on there for about 21 years. I imagine they have lost some of their tension over the years. Plus The machine shop was measuring the springs with the inner spring compressing at the same distance as the outer. In reality it sits about .22 shorter than the outer. That would bump the old springs above 500 open pressure. I bet the springs are real close in spring rates. My thoughts right now is the pressures are close to what the were. The cam has lived for 30 years. If coil bind turns out to be not an issue the. I will run them. Maybe I am wrong but the machine shop tester seems to run high. I am installing the 273 rockers as well.
 
340dartley said:
Keepers and retainer on the valve. Cylinder pressure to hold valve shut digital dial caliper measuring from seet to retainer spring seat.
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Unless you are gumby it's about impossible to be very close using caliper so to measure installed height. If you are that close, spend the money and get the correct tool then you will KNOW exactly what you have. Otherwise you are pretty much guessing.
 
yellow rose said:
Unless you are gumby it's about impossible to be very close using caliper so to measure installed height. If you are that close, spend the money and get the correct tool then you will KNOW exactly what you have. Otherwise you are pretty much guessing.
Click to expand...
Not sure why you need to be Gumby. It fits in there pretty easily.
 
340dartley said:
Not sure why you need to be Gumby. It fits in there pretty easily.
Click to expand...


When you are dealing with numbers small enough to use a caliper, and you are there, you need to keep the caliper parallel to the retainer and seat. There isn't much room and you can easily be off .030-.040 with what you are trying to do. Unless you have a special caliper. You'd be better off with a snap gauge and micrometer. As you might be able to tell, I'm not a fan of calipers. On a good day, they are accurate to only a few thou depending on what you are measuring.

You are close enough to coil bind that you need to be more accurate in measuring.
 
yellow rose said:
When you are dealing with numbers small enough to use a caliper, and you are there, you need to keep the caliper parallel to the retainer and seat. There isn't much room and you can easily be off .030-.040 with what you are trying to do. Unless you have a special caliper. You'd be better off with a snap gauge and micrometer. As you might be able to tell, I'm not a fan of calipers. On a good day, they are accurate to only a few thou depending on what you are measuring.

You are close enough to coil bind that you need to be more accurate in measuring.
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I agree. I am not a huge fan of calipers myself. It is what I have here presently. I am confident that I am parallel and I am as accurate as my calipers are. That being said a snap Guage would be better and to verify the numbers it is cheep insurance. I will take your advice.
 
I borrowed some snap Guages and got the same readings I had when reading with a dial caliper. I am sure they are more accurate but in this case it came out the same. I installed a ultralight spring I made from some wire and measured valve lift at the valve today with my dial indicator. .488 was my measured lift. All this together has my coil bind clearance at least .050 on all cylinders some more due to variances in installed height. I then installed my 273 rocker arms and custom pushrods I had from an old motor I built and took apart 20 years ago. I brought each cylinder to TDC compression stroke and adjusted the lash to 0 plus 3/4 of a turn. Had some honey dos to take care of so I will put the valve covers on in the morning and fire it. Here is a pic of the rocker set up.
 
yellow rose said:
Hey, you headers are junk. PM me and we can work out a price!!

I'm just pooping you. That is my FAVORITE header. They just don't make them anymore.

I will buy them if you want to take them off and sell them.
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LOL thanks. The car has a lot of sentimental history with me and my friends father. There is a lot of old world engineering from when the car was built.
 
what headers are they and what is the outside diameter? keep us posted cuz that is some killer spring load for a hydraulic with .500" my old 5303 hookers
DSCF0266.JPG
 
Marcohotrod said:
what headers are they and what is the outside diameter? keep us posted cuz that is some killer spring load for a hydraulic with .500" my old 5303 hookersView attachment 1714934505
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You are very lucky I am a nice guy. Those headers are JUNK JUNK JUNK. Who ever stuffed those up your butt gave you a serious screwing. Since I am said nice guy, I will, because of my overpowering concern of and care for the MoPar fraternity, take those junk headers off your hands. I'm sure we can come to an agreement on price.

Remember I only offer this because my concern is that you not kill a perfectly good combination with those junk headers.those are race only pieces, not for highway use (just ask ebooger, Calvin Elston and many others) and they are just WAY too big. I don't make this offer often but I'm in my helping mood. It won't last long.

PM me soon and I'll help you out.














LOL. Just kidding. I will buy them though if you want to sell. Best small block A body A engine OTS header.
 
Started it up this morning. Have some interesting results. First off don't know why at all but it started and idles way easier than it did before. I revel it up to 2000 and let it break the springs in. After having it running for a few minutes it died. Lol out if gas. Added some gas to the fuel cell and restarted. Starts and idles well. Snaps quickly when revving the motor. Now for the high rpm test. It still breaks up at high rpm. Now this is no load so just for grins I dropped it in to 2nd and power braked it pulled up to 3000 in gear clean. I am starting to think that no load revving is an invalid test. I don't have to opportunity now but I would venture to guess that it will pull clean when in gear WFO. The popping at 5200 was most likely the valve springs but I think I am chasing ghosts by revving in my driveway. Need to get it to the track or at least a deserted road.
 
yellow rose said:
You are very lucky I am a nice guy. Those headers are JUNK JUNK JUNK. Who ever stuffed those up your butt gave you a serious screwing. Since I am said nice guy, I will, because of my overpowering concern of and care for the MoPar fraternity, take those junk headers off your hands. I'm sure we can come to an agreement on price.

Remember I only offer this because my concern is that you not kill a perfectly good combination with those junk headers.those are race only pieces, not for highway use (just ask ebooger, Calvin Elston and many others) and they are just WAY too big. I don't make this offer often but I'm in my helping mood. It won't last long.

PM me soon and I'll help you out.














LOL. Just kidding. I will buy them though if you want to sell. Best small block A body A engine OTS header.
Click to expand...
Those headers are the same ones the I have but on mine they areally bit rough. Collectors are held on with springs still and have been dented and weld repaired many times . I like them though.
 
Sorry for the rough video I thought didn't realize I already started recording with the phone in my lap.
 
On a little more serious note. My neighbor who is a car guy as well recently had a pretty bad series of strokes. He typically has no problem with me running my open header car. He came home from the hospital this weekend and I went an knocked on his door to make sure my revving the motor up would not disturb him or his wife.
His wife answered and said he likes when I start it and it will do him good to hear it. Anyway just wanted to post some well wishes on here and send him and is family some prayers.
 
So now I am in the waiting game to get it to the drag strip. My plan was to baseline it with the current set up. Yes I changed the valve springs and rockers but that was more to make the current set up healthy. My problem is I really enjoyed coming home and working on the car in the garage. I am very tempted to go ahead with the intake swap just to make the engine look sexy and give me something to do. Lol.
 
340dartley said:
So now I am in the waiting game to get it to the drag strip. My plan was to baseline it with the current set up. Yes I changed the valve springs and rockers but that was more to make the current set up healthy. My problem is I really enjoyed coming home and working on the car in the garage. I am very tempted to go ahead with the intake swap just to make the engine look sexy and give me something to do. Lol.
Click to expand...


Refresh my memory. What intakes are you swapping?
 
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