OK, DWALL and I are working on his motor. We have measured for pushrods and a target preload of .040. No we have a range between 8.602 and 8.640" that need our pushrods to be. I know for a fact that I had a set of factory pushrods that measured 8.640 or so but I used them on another motor. Cant remember what they came out of. Now we have a set of Engine Pro pushrods that measure basically 8.594 and very up and down from there .002". We also have a set that measures 8.674 or so with the same + or - .002". If we used the shorter 8.594 pushrods, 2 of our valves will have no preload at all. I we used the 8.674 rods, we will have a few valves that will have up to a .110 preload which is way to high. My question is what did the 8.640 pushrods come out of? We can also order Comps 8.650 but we'd still have a .090" preload. So with that said, and without ordering custom pushrods, what would you guys do? Use rocker shims?
Need oddball pushrods.....Can anyone help?
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steve hughes
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Smith Brothers Pushrods come in .050" incraments. If it ain't on the shelf they will make and send it out the next day.
Mike Licht
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we have many sizes in stock, we can get others in one day. They come in .025 increments, remember the pushrods are not measured end to end but 120* on the radius with many companies. The ppushrod tool in the best thing to use to figure this out.
Mike
Mike
dwall
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Possible adjustable pushrods?
Nice to know replacements ARE available - thanks.
- Are there any durability issues?
- If we used them couldn't the preload be set according to each variation in pushrod length and is consistant preload desireable?
Nice to know replacements ARE available - thanks.
Just a Six??
OK! Who Farted??
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I have used adjustables & so have 2 friends without issues. All 500-600 HP motors. They work fine for when different lengths are needed.
Yeah I asked the question about possibility of them them spinning loose to TA yesturday and they said they have never had a problem. And for extra insurance, use locktite! I know it's normal for the Chevy guys to use them but I really havent seen many people using them in a TR motor with flat tappet cams. Maybe I'm just not around the top builders enough to know but I can usually find the correct lengths out of my big box so I've never really had this problem.
Mike thanks for that info! Did Prasad call you? We were going to see if you can help us on this one. As far as measurements, I do know different companies measure them differently and like I said, I usually have the right ones here so I've never had to worry about it. I've got a set of Engine Pro's that are 8.600" long but tip o tip measurements are actually more like 8.590's. So I looked on Comps website and they seem to measure from tip to tip from what I've read.
Can I ask you a question? What do you charge for a set of pushrods? And can we get a mixed matched set? Also, if we can get a set from you, how can we verify that we are measuring the same way your company is measuring?
dr_frankenstein
Mad Scientist
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I just dont like the added weight and inertia on the flat tappets to use an adjustable pushrod.
unless your adding an oiling face tappet...
A.j.
unless your adding an oiling face tappet...
A.j.
By the way, here are our exact measurements we need, obvious we dont need to be exact but would like to keep it as close as we can to try to retain a .040 preload on the lifters:
8.602
8.606
8.607
8.612
8.613
8.615
8.622
8.626
(2) 8.628's
(2) 8.640's
And these measurements are tip to tip measurements with a digital caliper.
8.602
8.606
8.607
8.612
8.613
8.615
8.622
8.626
(2) 8.628's
(2) 8.640's
And these measurements are tip to tip measurements with a digital caliper.
Mike Licht
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I have not heard from Prasad on this, Comp does NOT measure end to end they get their pushrods the same place I do, If your valve job is off by .040" you need to fix that. I can order an oddball set like that but they come is .025 increments so some are going to be off 8.600, 8.625 and 8.650 would be what I can get
Mike
Mike
Ok, do you sell .015 stackable shims?
Mike Licht
I was here first
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what would you do with them? You cannot shim the rocker shafts unless you shim them the same.
I understand that. If I can shim .045 on each pedestal, With the ratio of the stock rockers, it should raise the required length of the pushrods roughly .060. If I can do that, I have pushrods the correct lengths that I can use!
JDSfastGN
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ive got adjustables from Smith Brothers and they have been great so far.
Yeah we thought about going that route. Did you weigh them by chance before you put them in?
JDSfastGN
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No I didn't, I wasn't too worried about it. I Don't know all the theory behind it but I was told in Smokey Yunicks Buick v6 book that pushrod weight wasn't critical when it came to valvetrain weight and stability... I'm sure somebody will disagree but I haven't had any issues so far.
Mike Licht
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you can get shim stock at any tool room supply. I would be very carefull shimming them that much, the distance at the bottom of the shaft to the pedestal and the distance on the sides is different. I have seen a few guys split the pedestals doing this.
Ok, thanks for that information! I got a very generous offer from another fellow member so i think we are going to try to go the adjustable pushrod route! Might pick up some shims and see if we can get it to a very minimum but if not, we are going to use adjustables. Scott231, you are the man, thank you!!!!!
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