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Discussion Starter #1 (Edited)
Need some clarification if the parts I have gathered will work together. Specifically if the offset lifters, standard rockers and .100 pushrod length I have are correct.

Background is as follows
GM 817 Block/4340 Eagle crank 400sbc/400 mains/3.75 stroke/5.7 Rod Length4340 eagle h-beam rods/5700 B3D or 5700 BLW/Forged Wiseco Pistons/5016H3/11.4:1/.038 gasket/.010 Deck/tool steel rings. AFR227 1/2 set 1..6; 1/2 set 1.52 rockers/Jomar stud girdle. I also have lifters Comp cam 847-16 that are .180 offset, and springs from Comp cam 999-16.
Cam is as follows.


Thanks and sorry for the long post.
 

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Are you sure you will need the offset lifter? If you could stay away from an offset lifter I would. I'd rather put the offset at the rocker.

Pushrod length......you are going to have to mock it up.......
 

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Discussion Starter #3
Thats why I am asking cause ive never dealt with these offset stuff both in the lifters and valve spacing?
The AFR's have a 60/40 valve spacing and i thought thats what the offset was for?
The lifters I got as a package with the cam.
If you say to use offset lifters which ones do you suggest that can accomodate the 60/40? Its not out of the question to sell the lifters and get new ones as well as selling the rockers/stud girdle/etc.. and get a shaft mounted rocker, but I was thinking of a 1.7 and havent been able to find any.
 

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Its not out of the question to sell the lifters and get new ones as well as selling the rockers/stud girdle/etc.. and get a shaft mounted rocker, but I was thinking of a 1.7 and havent been able to find any.
This will enable you to do many different things to improve the valvetrain. You will be able to center the load in the lifter reducing side loading and wheel failure, and by going to a shaft system your offset can be set up to allow a larger dia pushrod to be used as well as the pivot length changed the give the rocker some room to do its job. Definitely the "right" way to do it, its just money.
 

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Thats why I am asking cause ive never dealt with these offset stuff both in the lifters and valve spacing?
The AFR's have a 60/40 valve spacing and i thought thats what the offset was for?
The lifters I got as a package with the cam.
If you say to use offset lifters which ones do you suggest that can accomodate the 60/40? Its not out of the question to sell the lifters and get new ones as well as selling the rockers/stud girdle/etc.. and get a shaft mounted rocker, but I was thinking of a 1.7 and havent been able to find any.
You should be able to get enough offset with just rocker for that head........and then run the lifter straight up. Like Shawn said, thinking about the side load. I have an offset intake lifter with my 7/16 pushrods.......it is something I watch closely.
 

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Discussion Starter #6
Any ideas for a shaft mount system with 1.7 ratio that wont break the bank? or 1.7 intake and 1.6 or 1.6x on the exhaust?

As far as the lifters I just need standard ones correct? Any recommendations? These were pricey when they were new?
 

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Discussion Starter #7
Why even run an offset lifter? Is offset different then valve spacing? If it is then why not just get a set of rockers with the correct valve spacing?
 

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Because you made need more I had offset intakes and rokers on my 23* stuff to clear the big runner because you could not grind into the port without making a vaccum leak
 

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Discussion Starter #10
The part I see is YT6617 which has a 1.65/1.55.
It says they are for the AFR227 but makes no mention of the 60/40 spacing.
Is the intake listed first?
 

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The part I see is YT6617 which has a 1.65/1.55.
It says they are for the AFR227 but makes no mention of the 60/40 spacing.
Is the intake listed first?

Pretty sure that is the correct part #, but I would verify directly with YT or a dealer here in the US like Chris Straub. Yes, 1.65I/1.55E.
 

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Discussion Starter #12
Because you made need more I had offset intakes and rokers on my 23* stuff to clear the big runner because you could not grind into the port without making a vaccum leak
So your saying to keep the offset lifters?
What is the desired difference between lifts from
intake to exhaust if any? For example if i use the
yella terra 1.65x1.55 intake lift will be .709 and exhaust
.674. Ive always heard exhaust will exit no matter what so
have intake more?
Any thoughts? If it does matter how much split between them?
 

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I dont know how much push rod your going to have to move but its not unheard of to run them depending on the port and size rod you choose. My 15* has a offset intake lifters and .750 offset rocker to clear.
 

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Discussion Starter #14
What about the difference between intake and exhausts lifts?
Are there opinions which should be more and by how much and any theory behind it?
 
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