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Strap on the JATO
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Discussion Starter #1
A couple of my intake rockers seem to be off the valve stem
1/4 of the width of the roller tip. All the exhaust rockers are
perfect. I've got Manley guide plates, Crane roller setup, Crane gold
rockers, 990 heads. Do the intake rockers seem to ride off the stem
normally? I've heard of grinding, cutting, re-welding etc. I've also
heard of the adjustable Dart's. I wanted to check with some of you
knowledgeable people before I do anything. Thanks in advance.....
 

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steelcomp was here
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26,512 Posts
Yes to all the above. You basically need to do whatever it takes to get the roller tip centeted over the valve.
 

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Strap on the JATO
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305 Posts
Discussion Starter #3
So what do you guys do under this situation? I know someone's
got an opinion here, Steelcomp, Warp, Cstraub, please help a
brother out.....:)hand
 

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Strap on the JATO
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305 Posts
Discussion Starter #4
Steel, you were replying while I was typing. Is it weird that I'm
only having trouble with the intake rockers?
 

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steelcomp was here
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Steel, you were replying while I was typing. Is it weird that I'm
only having trouble with the intake rockers?
You can loosen the guide plates like Art said and try and shift them around, but chances are you won't get them right. I've never tried a set of the adjustable ones, which might not be a bad deal. Some guys just cut them and torque the studs down to hold them in place. I'm not a real fan of that idea. IMO the only right way to do it is cut them, align the PR's, and weld them back together. If you're going to wire weld them, get an old head you don't care about. You can just tack them together on the set you're running, then bolt them down to the old head to hold their shape and weld them without getting the splatter all over. Tig welding would be better.
 

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Strap on the JATO
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305 Posts
Discussion Starter #7
Thanks Guys! I tried moving them around & even grinding a
little on the inside of the hole, as directed by the shop I had
everything done at, but it didn't do any good. Does anybody
have any info on the darts? It looks like adjusting for one
rocker will effect the other?
 

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Thanks Guys! I tried moving them around & even grinding a
little on the inside of the hole, as directed by the shop I had
everything done at, but it didn't do any good. Does anybody
have any info on the darts? It looks like adjusting for one
rocker will effect the other?
I ran into the same deal on my engine and I bought the Darts and they are kick azz, work great. Give 'em a try you'll love'em.
 

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Loosen the guide plates and see if you can center them, if that don't work cut them in half, center the rockers and weld them up!..
Hey gofast, Its casting flaw and the bbc is notorious for this situation. The intake rocker tips tend to run to the back of the block. Roller tips help the situation. I personally would not cut in half but v the guide plates and center. cut about 3/4 thru and bend accordingly while still bolted down but loose. Center stuff up and if so inclined reweld off the head. then you may come into tip angle problems and wear on either the guide or push-rod, so keep an eye on that. Iron heads are good for this and is fixable. Just be careful of wear paterns that may pop-up. In my 2cents.M
 

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Nobody
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Hey gofast, Its casting flaw and the bbc is notorious for this situation. The intake rocker tips tend to run to the back of the block. Roller tips help the situation. I personally would not cut in half but v the guide plates and center. cut about 3/4 thru and bend accordingly while still bolted down but loose. Center stuff up and if so inclined reweld off the head. then you may come into tip angle problems and wear on either the guide or push-rod, so keep an eye on that. Iron heads are good for this and is fixable. Just be careful of wear paterns that may pop-up. In my 2cents.M
Well, regardless the problem is either too wide or too narrow and needs to be centered and a partial cut don't always work only if it's close, guide plates are not a precision piece either and you can thru a bunch before you get some that are really close, especially with factory ones!... But a partial cut does work at times, I've done it before!..
 

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steelcomp was here
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Well, regardless the problem is either too wide or too narrow and needs to be centered and a partial cut don't always work only if it's close, guide plates are not a precision piece either and you can thru a bunch before you get some that are really close, especially with factory ones!... But a partial cut does work at times, I've done it before!..
Never been able to get that to work. It changes the distance between the two stud holes on the guide plate. I guess if the holes are large enough, or like Art says, if the error isn't bad it might work, but in most cases, they need to be cut completely, adjusted individually, and welded. This is fine for someone who can do this kind of work in his garage, but not everyone can weld, or has a welder, in which case I think the adjustables are the ticket. Probably try them myself on this next build.
 

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Nobody
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Never been able to get that to work. It changes the distance between the two stud holes on the guide plate. I guess if the holes are large enough, or like Art says, if the error isn't bad it might work, but in most cases, they need to be cut completely, adjusted individually, and welded. This is fine for someone who can do this kind of work in his garage, but not everyone can weld, or has a welder, in which case I think the adjustables are the ticket. Probably try them myself on this next build.
Well, it hardly ever works,LOL. Like I said I'd go thru a bunch getting them close and some would be close enough, but 9 out of 10 I'd cut them and that takes a lot of time, now that the adjustable ones are out gotta be the way to go!..
 

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mo balls than $cents$
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I ran into the same deal on my engine and I bought the Darts and they are kick azz, work great. Give 'em a try you'll love'em.
adjustable dart guide plates are the only way to go:)devil make tip alignments soooo much easier.
 

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Strap on the JATO
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Discussion Starter #15
I think the Dart's are the way I'll go, The web-site says for Dart
heads though, will they work for the GM's?
 

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Had same problem with AFR heads on SBC. Used AFR guide plates supplied and could not get rockers centered on valve tip. Purchased Isky adj. g plates to resolve issue.
 
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