What's wrong with this cam card?

Jimmy 2Coupes

SCCoA Member
Who can figure out what's wrong with this cam card besides the, "3.8 TURBO // BIRD". Keep in mind these spec's were supposed to be based on a 1.73 rocker ratio. :confused:


Comp%20Cam%20Card.jpg
 
I was informed by a Comp Cam's tech that the .285 was gross lobe lift, (not lift at .050) which would mean a 1.79 rocker ratio would be needed to come up with .510 gross valve lift. With 1.73 rockers I come with .493 gross valve lift. My question is would that mean some of the other spec's like total duration, overlap, ect. would be off as well using 1.73 rockers.
 
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Usually they tell you on the cam card WITH 1.73 rockers or WITH 1.5 ect..I dont see that..ALso 114 lobe seperation..Your car will run hot with boost and that type of lobe seperation..Anyone else have comments for him?
 
when i got my grind from comp i was told that you cant change the stock lobe serperation. My cam was profiled with a 112* LSA....and after the grind it was still 112*. My cam has a .493 lift both intake and exhaust, with a 210/220 durration @.050". This is Coy Miller's stage one cam. His old cam had a .493 lift and a 210/210 durration, but he changed it because of boost blowing out the exhaust. Now that its not a single plane cam, i guess it performs much better. The guy i talked to at Comp. looked up Coys orders and ground my cam to Coy's specs after talked with Coy's sales rep. I really dont see anything wrong with what you got there. On my card, it does say all my specs with a 1.73 rocker ratio. Here's a copy of my card, Coy stage 1.
 

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Your car will run hot with boost and that type of lobe seperation.

I've actually had this engine/cam installed in my 95 SC for the last year but it's never ran hot and it see's 14 psi of boost regularly. Thanks for the tip though.

fastsc92, thanks for posting a pic of your cam card. It's interesting our cam card's have the same part #'s but different grind #'s. I've had this engine/cam installed for the last year and it really doesn't feel bad at all, in fact it runs very good, especially after a Jerry W. tune. I was looking over the cam card latley and noticed the discrepancy in the spec's so I was just wondering what else besides valve lift would be off between a 1.79 & 1.73 rocker ratio's. I'll have to give Comp a call and ask more questions but right now I'm not really too concerned about it since the car run's like a scalded dog as is. Thanks man. :)
 
Seems to me like you got the "early" profile James and the rest of us got the newer one. I'm running the same cam (210/220) in my car so you know it can support some HP. :D BTW, it really likes 1.8 rockers. Too bad I bent my pushrods using them. It was worth 10rwhp on the big end.
 
XR7 Dave said:
Seems to me like you got the "early" profile James and the rest of us got the newer one. I'm running the same cam (210/220) in my car so you know it can support some HP. :D BTW, it really likes 1.8 rockers. Too bad I bent my pushrods using them. It was worth 10rwhp on the big end.

Hmmm... isn't that interesting Dave? The 2 of us picked the 'right' profile about 4-5 years ago. I didn't need any help from Coy to get the right one. :)

Although, my new one's alittle different. And no... it's not a solid roller, the valves don't need adjusted... it just ticks alittle. :D

Oh.. and on the wide lobe sep making it run hot... Ummmm.. Hunh? I've never, in all my years of building engines, working at an engine shop, racing car and talking with Crane and Comp both EVER heard of that one. Actually, with a blown motor, the wider the angle the better. 113.5 is the STOCK sep angle on most of the 89-93 cams and 114 is stock for the 94-95s. If I could, mine would be up around 116 or more, but you can't change the sep anlgle on a regrind. What does change with the more agressive regrinds is the advance. The stock cams had 5 degrees advance and the more the basecircle is cut, the more that goes away. My grind like Dave's still had 4 degrees in it.. the new one had 1.
 
so you guys both have that lift (.493) and that durration (210/220)? How do you like it? I'm excited to get the car together and see how it performs. Does it have a noticable idle? I added a set of fully ported heads with stock size valves as well with new stock springs, and a raised top. I hope to make good power all around, and have a little shake in the idle to make it known that it has a cam. With the heads and cam, as well as my N20 kit..i hope to run a 13 flat, if not high 12's. But we will see.
 
Jimmy, not that it makes any diff but those numbers actualy work out to 211 deg duration and 113.5 lobe sep.

Stan W
 
You will make more power with a blown car and a larger lobe seperation however its been my experience a car will tend to run hotter with one...Most of us know that a larger lobe seperaton will allow less boost to pass through the exhaust while having a slightly smaller lobe seperation will allow a bit more to pass through. It's another one of those comprimises..The fact that a larger lobe seperation cam will prevent less boost leaking out the exhaust will giv eyou more power however it also keeps the temps slightly elevated...Ehh maybe its just me
 
BTW, it really likes 1.8 rockers. Too bad I bent my pushrods using them. It was worth 10rwhp on the big end.

Ya Dave, I thought about maybe using 1.8 rockers to bring this cams valve lift up to the advertized 510, (would be 513 actually) but I don't know if it would be worth the effert and I definitely don't want bent pushrods. Have you gave up on using them all together or will you try using them again?

What does change with the more agressive regrinds is the advance. The stock cams had 5 degrees advance and the more the basecircle is cut, the more that goes away. My grind like Dave's still had 4 degrees in it.. the new one had 1.

That's interesting Steve. Unfortunately my cam was never degree'd so I have no idea how close or far away it's installed relative to the 110 ICL installation my cam card is based on. It's installed using the stock timing set. Got a ball park guess as to how far off it is either way? Anyone?:D

Jimmy, not that it makes any diff but those numbers actualy work out to 211 deg duration and 113.5 lobe sep.

Stan, that's exactly the type of info I was looking for. Like I said in an earlier post, I think I'll just leave it along for now. Thanks for the help.
 
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I bent two pushrods using 1.8's although it's maybe possible they were bent before and I just didn't notice. But the two problems were, first the stock pushrods are junk, and second, the altered geometry with 1.8's caused a few of the pushrods to rub on the edge of the pushrod holes (the holes in the head where the pushrods go through, can't remember the real name of these holes...) Anyway when rebuilding the heads I fixed it by getting some Trick Flow one piece hardened chromoly pushrods, and chamfering the edges of the pushrod holes. I'm pretty sure there aren't going to be any more bending problems.
 
That is exactly what I found as well with the pushrods. Since I do not intend to tear the motor apart and chamfer the pushrod holes, I am leaving the stock rockers in this motor. Next motor will get the 1.8's and stronger pushrods.

Fast92 that cam will give you *just* noticable lope at idle most people will just think its a POS Tbird lol. Some people will notice.

You should have no trouble with 12's on the nitrous. I'm running 12's without nitrous on mine. ;) Mid 13's on motor should be cake.
 
i sure hope to see 12's......we'll find out. Brian at FFW had an older Coy cam with a 210/210 durration. Mine is 210/220, and i really liked his idle. While i was on the dyno and his was idleing in the lot, a few people stopped and noticed it. Like you said, its just enough to hear it, but like you said, people might think its a ratty t-bird. But that ratty sounding t-bird can run 12's......now thats the part i love.
 
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