Suitable push rods for L05 CSB Vortec swap?

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Dec 21, 2017 | 03:22 PM
  #1  
Hello
I'm in the progress of doing a head swap to Vortec heads modified for higher lift cam.
The engine is a L05 factory roller block rebuilt to carb.
When I disassembled the top end i discovered that one of the push rods is bent. Not much, but I need to switch it.

Should I switch them all?
I see prices vary a lot. I know I must have hardened push rods.
Should I avoid push rod sets for 40-50 USD?

I cant find the exact same length anywhere. Mine measure 7,197". The closest i can find is 7.218"
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Dec 21, 2017 | 09:33 PM
  #2  
Re: Suitable push rods for L05 CSB Vortec swap?

Your push rods nominal length is 7.200". The difference you are measuring is because of the oil hole.
A decent set will cost about $100.
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Dec 22, 2017 | 03:56 PM
  #3  
Re: Suitable push rods for L05 CSB Vortec swap?
Best convenient unexpensive ones to get are Trick Flow. https://www.summitracing.com/parts/t...7200/overview/ In the $100 neighborhood as stated above. They come in .050" increments, and .025" within certain ranges of length. Exact length can vary WIDELY without any noticeable effects on anything. Stock length is something close to 7.200", can't recall exactly.
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Dec 24, 2017 | 03:13 PM
  #4  
Re: Suitable push rods for L05 CSB Vortec swap?
Ok, thanks
But is it correct to assume that increasing the cam lift by app 0.1" would require 0.05 shorter push rods to maintaine the same rocker arm geometry?
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Dec 24, 2017 | 04:22 PM
  #5  
Re: Suitable push rods for L05 CSB Vortec swap?
Quote:
But is it correct to assume
Never.

Quote:
increasing the cam lift by app 0.1" would require 0.05 shorter push rods
ABSOULTELY INCORRECT.

The "nose" of cam lobes is almost always as big as it can be, and still go into the block. Stock or aftermarket.

The way a cam is made "bigger" is to grind off the BACK side of the lobes. Which is why you can REGRIND a cam to make a "bigger" one (within certain other limits) but it's EXTREMELY difficult to make a cam "smaller".

In general, if push rod length needs to be changed due to a cam swap, it'll be toward LONGER push rods. But every situation is different; which is why the way you started out your sentence is SO WRONG on every possible level.

If you want to get it right, assume NOTHING, and measure EVERYTHING.
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Dec 26, 2017 | 06:00 AM
  #6  
Re: Suitable push rods for L05 CSB Vortec swap?
Thank you for a VERY clearyfying answer! I understand why my assumptions were wrong.
I'm going to buy one of those pushrod length check tools.
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