Where can I buy these at? The part number is 300-8243. I know I can get them at Jegs, but they are on back order and I need to get them as soon as possible. Thanks for any help.

 

If you really have LT4 rockers[ not 'hotcam kit' ones] that are on an LT4, the nuts are different... [they don't'adjust' they tighten down to a certain point... different studs, too]
Regular locknuts for regular[including Crane Gold, hotcam kit, etc]studs, [including LT4 heads sold by GM], you should be able to get no prob..

 

I am not sure if they are from the hotcam kit or if they are the ones on a real LT4. I just know that it is the crane lt4 1.6rr and the part number to the lock nuts I need is 300-8243. I was told that these are self adjusting rockers. Thanks for any and all help.

 

Look at the pics of 'A' LT1 and 'B' LT4 heads about halfway the page here, to see the difference in the studs I am talking about.. http://www.malcams.com/legacy/misc/LT4.htm

An LT4 that came from the factory on a car[not 'LT4 heads' bought from GM they have reg 12552126 3/8" LT1 studs on them] uses a 'shouldered' stud, and you don't 'adjust' the valves you tighten the nut down...
I would say that odds are you have the regular LT1 3/8 studs, so regulare 3/8" nuts and locks..
You just have to be sure that you have regular 3/8" studs, or 7/16 studs, or LT4 'shouldered 7/16 studs..
I am not familiar with the part # you give, sorry..
You mean 'self aligning' not self adjusting, right?
Heres' Crane info for the Gold roller rockers..
http://www.cranecams.com/master/goldrace.htm
From that chart I would say you need Crane 99795 nuts..
I did a search on your p/n and came up with nothing..
Charlie

I can send you a pic of a regular Crane [as in hotcam kit etc] 1.6 self adjusting RR and locknut too, if that would help you.. [I have some here someplace]