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L20B Rod Fitment Help


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#21 Stoffregen Motorsports

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Posted 10 October 2017 - 06:25 AM

Resized.

 

They take so little material out that the change in length is negligible. Ideally only a few thousandths.

 

Yes, they should do all four, but that's more of a balance thing.



#22 jcd0402

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Posted 11 October 2017 - 07:39 PM

Yup, resized as Stoffregen said. They remove material from the rods and the crank. But the removal is so minute that I would like to think it won't mess with the compression. 

 

About the weight difference, I do believe there will be some, but nothing that can't be fixed with a grinder and a scale. :)  


You know this is a beautiful car; it's still got a good engine but until we get that piece that fixes the engine its not going anywhere.


#23 datzenmike

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Posted 11 October 2017 - 07:41 PM

The thicker bearing would make up for it.


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#24 jcd0402

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Posted 11 October 2017 - 07:50 PM

The thicker bearing would make up for it.

True, maybe that's why they made me get a 0.020 undersized rod bearing . To take .010 from the crank and .010 from the rod. 

Just making a guess, I'm not really sure. 


You know this is a beautiful car; it's still got a good engine but until we get that piece that fixes the engine its not going anywhere.


#25 datzenmike

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Posted 11 October 2017 - 08:00 PM

I think only the rod cap bolt area is trimmed to make the big end less oval and more round. They don't remove 0.010" all the way round the rod and cap.


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#26 jcd0402

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Posted 12 October 2017 - 06:45 PM

I think only the rod cap bolt area is trimmed to make the big end less oval and more round. They don't remove 0.010" all the way round the rod and cap.

Oh, okay, guess you learn something new every day! Specially here :thumbup:


You know this is a beautiful car; it's still got a good engine but until we get that piece that fixes the engine its not going anywhere.


#27 jcd0402

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Posted 12 October 2017 - 06:51 PM

Ask them to measure the crank to see if it can just be polished.

 

Also make sure to get good tri-metal bearings. Aluminum bearings are horrible and have lots of problems. Clevite makes tri-metal bearings and anything stamped with an "NDG" is a factory type bearing.

It has TDC and R2040 stamped on one side and T-2 on the other side.


You know this is a beautiful car; it's still got a good engine but until we get that piece that fixes the engine its not going anywhere.


#28 scooter

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Posted 14 October 2017 - 07:08 PM

[quote name="datzenmike" post="1522739" timestamp="1507641586"]

Rods bored???

[Quote]

I thought I read that's possible... take material from the parting joint, reassemble rod then hone to size ....
I could be wrong....
If that's the theory wouldn't that effect the install height of the piston?
Should all 4 be done to match?
Maybe it's minimal or not even possible.. I really don't know for certain....

 

your right... and yes. usually you lose 4-10 thou deck height from this operation which isn't a huge deal for one of these.

if your gonna do one, may as well do them all and INSTALL NEW BOLTS in the process. 

 

alot of the time when you put in arp bolts you have to automatically do this as the clamping loads are higher and distort the rod compared to stock.