[WANTED] Looking for 7.20" push rods...

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No, they probably would be custom push rods. (unless those 273's would work?) This is what happens after they mill the heads and deck the block.
 
360 LA

Just like this... but shorter.

pushrod.jpg
 
I just bought some Comp Cams 7.342" for my 273 build. Did you use a pushrod checker to determine the length? Crower has pushrod kits where you cut the tube and install the end. I have a customer who races Mopar powered stock cars that takes stock pushrods apart, shortens the tubes and re-installs the cups. He has never had a failure. Toolmanmike

http://www.summitracing.com/search/...ll-Length-in/7-342-in/?keyword=mopar+pushrods

http://www.summitracing.com/search/...ll-Length-in/7-325-in/?keyword=mopar+pushrods
 
The one you see in the picture there is 7.334, and it's to big. Barely fits under the rocker without the adjuster even in place.
The thing is it comes to 7.2" but ain't I suppose to add .025 to that? If that's the case I guess I really would need 7.225.
Oh, and I am using a Trick flow adjustable pushrod to measure length. It starts at 7.2, and that's what seems to fit. I don't even have to adjust it further.
 
What you need is a ball/cup pushrod for an adjustable rocker/hydraulic lifter combo, which is about the length you mentioned. Only the 340 6-pack engines came with them as original equipment.

273 pushrods are too long because they had solid lifters - 7.5". When they switched 273's to hydraulics, they also got the stamped rockers. The 7.342" pushrods are advertised to work with hydraulic lifters but I found them to be too long also.

You'll need to do some research for part #'s. Summit has some good search features for parts. Crane had the right length but don't know if any vendors have any leftovers. I don't have the part # handy at the moment.

Be careful because there are 2 ways to measure:
1) Overall length - tip of ball to top of cup.
2) Effective length - tip of ball to bottom of cup.

I think the "effective" length is usually used.
 
If "effective length" is the preferred measurement I wish the manufacturers would state that. I can measure that if I knew I needed to. Mike
 
Your right, I keep hearing the "effective length is what is used the most, BUT the adjustable Trickflow I have is end to end, and so is the Crane 7.334. So yes, I have to be careful who I talk to. I called Crane, they have nothing that size anymore, nor do they make custom sets anymore. I called Smith Brothers, they can make them for me for $180.00, and another place said $150.00 so I was hoping maybe someone on the fourm had a set they'd be willing to sell for cheaper.
 
I decided against Smith brothers mostly because of the price but because of the 20 questions they ask for proper fit. I need a stock replacement pushrod just shorter. If I was building a exotic race motor they would be the first I would call.
 
Although they are not available, Summit shows these Crane pushrods as being 7.330" overall! I think that's the ones I have been using which are around 7.2" "effective". Also, "I think" that when I had some Comp Cams pushrods advertised at 7.3-something, they actually measured 7.5" overall! If you can find some or have someone confirm the "effective" and "overall" length of any brand pushrods, you might find something that works.

I think that the Summit G-6420 should work even though it shows their "overall" length at 7.234". The more I look, the more it seems that the way different companies show the measurement is NOT consistent. I suppose you can ask for a rep to specifically measure an actual pushrod for the overall and effective length instead of relying what the book or computer says.

Crane:
http://www.summitracing.com/parts/CRN-69691-16
 
I used a pushrod checker and measured overall length and ordered the Comp #7692-16 which is overall length. Just .008 difference.

Mike
 
toolmanmike said:
I used a pushrod checker and measured overall length and ordered the Comp #7692-16 which is overall length. Just .008 difference.

Mike
Click to expand...

If you have a dial caliper, you can measure the depth of the cup and subtract the depth from the overall length to get the effective length.
 
It seems to be from what I am noticing... the overall length seems to be what they are going by. Which is the opposite of not only what I was told, but also diagrams I have scene on the net! We just have to make sure we ask the company before we buy the pushrods. I'm glad someone else noticed this as well.
I measured my cup and it reads .1585 Which means my effective length is actually 7.0415

Joemopar, it's hard to read with that flash, it's exactly at the wrong spot! :)
It looks like 5/16's though?? If so that would be 7.3125. That's about .10 to long if I am reading that correctly.

Why does it seem like we should move this thread to a different spot on the forum? :)
 
I can't see any good reason why cup pushrods would be measured any way other than overall length. The ball end measurement isn't subtracted so why subtract the socket depth? I'm sure there's a good reason.
 
Well... Before I even questioned the length of those Summit Push Rods, I called them and they told me that they would be fine for a stock replacement, and nothing more because they are simply plain steel pushrods. That would explain why they are $37.00 as oppose to the $180.00 for Smith Brothers even if they did fit.

How did you figure out that they are hair more than 7.375 OAL though??
 
toolmanmike said:
I can't see any good reason why cup pushrods would be measured any way other than overall length. The ball end measurement isn't subtracted so why subtract the socket depth? I'm sure there's a good reason.
Click to expand...

Cup depth from the lip to the bottom may vary and the "effective" length is the actual, physical, mechanical pushrod length, like the overall length of a ball/ball pushrod. The cup does nothing more than locate/capture the adjuster. Stamped rockers have the cup built into them.
 
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