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sts70004
09-05-2009, 02:45 AM
I have an 89 5speed and I have found on this website that my cam is as follows:

89 Manual

Intake .448", 194 @ .050", ICL 106
Exhaust .457", 202 @ .050", LDA 110

I understand the first two numbers, but what is the .050" and ICL and LDA mean? And then second of all, if I wanted to use Roller Rockers to increase the lift and reduce valvetrain friction with stock valves and springs, what would be the limit in terms of ratio? Or what would you recommend? I'd rather not replace the cam but if I could get the same results or better for less money I'd be open to it. It just seems like it might be a bit of a job.

Stupid Canuck
09-05-2009, 04:20 AM
Harland Sharp and Morana have 1.8 ratio rockers but might require different studs and possibly machining. There are some previous posts. Cam would be cheaper, unless you miss the allen head bolt on the timing cover under the oil pump.

The stock valve springs are only capable of .520 lift, in good condition.

sts70004
09-05-2009, 04:27 AM
Harland Sharp and Morana have 1.8 ratio rockers but might require different studs and possibly machining. There are some previous posts. Cam would be cheaper, unless you miss the allen head bolt on the timing cover under the oil pump.

The stock valve springs are only capable of .520 lift, in good condition.

Well after reading some more posts about cams and rockers I came to the same conclusion. And I did catch that allen head bolt in a couple people's posts :-). I'm not ready for the cam yet but I want to get it all planned out in advance so i'm not sorta throwing parts on helter skelter. I'm trying to get things that compliment each other and such. I know that the Roots style blower is very sensitive to inlet restrictions, and since it doesn't pressurize the air, less boost as a result of things after the supercharger is a good thing actually, and Cam came to mind. I'm starting on my exhaust this sunday, so we'll see how that goes. Thanks for the reply

thunderkid84
09-05-2009, 11:20 AM
What are your plans for exhaust ?

sts70004
09-05-2009, 09:03 PM
Well for the imediate future, simply getting rid of the resonator, since that has the most restrictive part of the exhaust on it, and the crimp, but my plans are to run 2.25 or 2.5" downtubes to a magnaflow or similar muffler as the resonator, and then Borla or Flowmasters for the mufflers. At the magnaflow, I'll probably go to single 3" or similar. That's for next summer. The cam is along the same timelines, but I want to get research done ahead of time.

thunderkid84
09-05-2009, 09:59 PM
Sounds good.

The best thing u can for your sc is to read all the info u can on these forums.

It's a great community of friends too.

sts70004
09-05-2009, 10:12 PM
So I still a little confused as to what all the numbers on the camshaft specs are. Can someone explain them to me? I know what lift and duration are, but what are the other two?

Stupid Canuck
09-05-2009, 10:37 PM
Duration @ .050 lift (or more) ... standard rating stuff
Forget the anagrams but the last numbers are lobe separation.

sts70004
09-05-2009, 11:03 PM
ooh now I get the .050 part. Thanks for the help