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Basically, it opens the valves more, allowing more fuel/air in and more exhaust gases out.

The draw back is if you are not careful and sure they will work with your motor, you could bend your valves due to them hitting the pistons.
 

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Before my GMPP 1.6RR's and LT4 springs F body LS1's would have a car length on me @ 80mph, after I'm dead even @ 80mph.

After my EM long tubes, Hot cam and new chip I'll have the car length @ 80:thumbsup:
 

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BubbleHead said:
The draw back is if you are not careful you could bend your valves due to them hitting the pistons.
:surprised I hope this doesnt happen to me....I am installing a set of Harland Sharp 1.6 rollers in the spring.:lookinup: I will have a set of 7/16 stud 1.5 Harlad Sharp roller rockers for sale in spring if anyone is interested drop me a pm.:lookinup:
 

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Valve clearance is not a problem with the stock cam or the hot cam, the thing you need to look out for is valve spring coil binding with stock springs. That is why I replaced my springs.
 

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84GrandSport is not running a stock motor, his sig says 383. But, valve spring binding is another important point to remember.
 

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DC Crew
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Discussion Starter #7
Thanks for the info.I'm not sure what I want to do just looking at different things. Do you think this is a worthwhile mod?
 

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the change made a nice difference on my old engine. I figure to go with 1.6's again on the new one. The added valve stroke is not that much that you should fear piston interference. Most important is to check your push rod length and make sure the rocker bearing stays centered on the valve stem. Off center load will cause premature wear of the guides.

I will also change out the springs with the new barrel type springs from Comp Cams. These springs behave like the dual rate suspension springs and consequently reduce valve train dynamic weight.
 

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raidmagic said:
Do you think this is a worthwhile mod?
Yes I do, even if you dont do enything else. But I had planned from the start to replace the cam. Also the rr's do make a little more noise than the stockers. If you go with the 1.6's you will lose some manifold vaccum but that should not be a big deal if your running MAF, my MAP system has some trouble at Idle but I'm getting that fixed with new programmming after the hot cam goes in.
 

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BubbleHead said:
84GrandSport is not running a stock motor, his sig says 383. But, valve spring binding is another important point to remember.
I have about 5000 miles on my new engine so I doubt I have to worry about valve springs either.:)
 

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Didn't '87's have roller rockers to start with??
I think they did so there would be no gain going to rollers
the ratio change.... I hear 1:6 intake 1:5 exhaust is best with a factory cam
the stamped steel roller rockers get weak, as low as 1:42 was found in a stock engine so just replaceing them is a gain.
why not get a cam with a profile you like and some good (1:5)roller rockers to cut down on valve train stress??
 

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JCswm said:
Didn't '87's have roller rockers to start with??
No, roller lifter's yes, LT4 was the engin with factory RR's
 

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84 GRANDSPORT said:
I have about 5000 miles on my new engine so I doubt I have to worry about valve springs either.:)
Milage has nothing to do with it, the lift of the cam, x's the rocker ratio can not excced the springs lift or crush if you will.. If it does the springs coils will bind and bend push rods and other stuff.
 

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Discussion Starter #15
I would agree but I don't want to spend the money and not be able to use it in a new motor. I am trying to do stuff that is A) reasonable in price or B) useable on a new engine. i.e. headers.
 

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C4CRAZY787 said:
Milage has nothing to do with it, the lift of the cam, x's the rocker ratio can not excced the springs lift or crush if you will.. If it does the springs coils will bind and bend push rods and other stuff.
Ok I will contact my engine builder & see if it would damage anything putting them in?:huh: Thanks for the info guys.:thumbsup:
 
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