Anyone out there running this cam in a 78 L-82 ? Comments?

 

Oughta run pretty good overall

 

I built two 406 engines last year, one got a 412 cam and one got a 422. The 422 has a slight lope, the 412 smooth idle. Both produce torque and good idle vacuum. Timing curve is different than a flat tappet cam for best performance.

 

I used this cam in a 383 a few years ago - agree, pretty good torque. I would not hesitate to use it in a 350-383 with good heads.

I think you would see a positive impact from the cam alone, but would suggest you might want to also look into heads for the greatest overall impact.

 

Look at the specs of the L-82 cam @ .050. Then look at the Comp cam K12-422-8 of only 218/224 110

Other than being a roller cam it is extremely wimpy with less intake duration than the l-82. So it is kinda a dumb idea. You are going backwards instead of forward.

Roller VS Flat You can run a lot bigger roller and still have higher vacuum.

 

Thanks for the info. This is what Comp suggested as a step up. I will look deeper.

 

I would be careful when some people post this cam as "wimpy". Engine HP and Torque numbers mean different things to guys who race cars versus the average guy building a Corvette for street use. Make sure you listen to the people who understand the difference, and that you build a motor for what YOU want. It is very common for race boys to push for a motor that works great at 5000 RPM, but if you never push the motor that hard, then its worthless. If you read enough about it, you will find that wise people will push you to build a motor with a strong torque curve in the 2000-4000 RPM range, where most people drive, and where this cam falls. What happens at 5500-6500 is irrelevant, unless that is your intent, and truth is you can't have both. Its a trade off one or the other,.....unless you just but a big block in it, then you have so much torque you can't use it!!

 

Thanks, I am really hesitant now on what to do. This kit isn't cheap. The engine has headers, alum. hds 64/200. I dont race it just looking for a good street performer. Appreciate your comments.

 

I agree - depends on what your goals are. Street driver or racing - two very different applications. I assumed the OP was working on a driver not a racer. The XR270HR is a decent street driving cam with good torque.

 

I'm running that cam in my new 350 Jon Barrett Hot Rod Engine that I put in my Vett last year. The engine is Blue Printed and balanced, roller rockers and Iron Eagle Heads . Really great low end torque . I am running Hooker Header side pipes with STS Baffles and with my combo I have a real radical lope!
It turns heads just idling.
Great can for around town driving. I think you will like it.

 

I would tend to stay away from 110. The marine cam is built with 112 and a later opening intake event for more vacuum and increased mpg

http://www.compcams.com/Company/CC/c...?csid=170&sb=2

 

Again, the suggestion for a "marine" cam moves the powerband higher, away from what the average person needs in a street car. The OP did not say he wanted a race car. I really think the people who "race" cars lose sight that not everyone wants a race car. And if you build an engine to be good in a race, it moves away from being good for the street. I am not saying you need to build a weak motor, but one that provides good torque in the RPM range that you can legally and responsibly drive a car on the street, and more importantly, how most people actually drive their C3 Corvettes on the street. What the engine produces at 6000 RPM is irrelevant.

I will say that most "race car" folks know way more about cams, timing, and building engines than I do. So, I could be wrong about what I am saying technically. But what I do know is that the hardest thing to do is to make sure the advice you are given, on this forum or elsewhere, is coming from a source that is trying to provide you information that applies to YOU, and aligns with what YOU want for your car, and not driven by their own desire to have the biggest motor, the fastest car, etc. If you follow that path, you need to go straight to putting a 70000 HP 8000 Cubic Inch jet engine in the car, or someone else will, and then you are just second best. I personally don't have those ego issues, and want a car that works well on the street.

 

Do you REALLY consider a rpm range of 1800 to 5800 to be a race cam? We are talking about an L-82 That was sold with forged parts and a just under 6000 rpm red line.

You must have NO experience with roller cams! They run so much smoother than the equivalent flat tappet. I also pointed out that his first cam even with less total duration has and earlier intake valve opening. Comp cams does this so the motor will sound like it has something in it with reduced idle quality. I call these all show and no go cams. They are are made for sound not efficiency. Factory cams are often 114 -116 lobe separation. It is for efficiency.

As for me I don't buy off the shelf cams for my builds, I go to the lobe book and have the valve events set to my specs. I'm also Pro altered firing orders.

 

Interesting always wondered how a marine cam would behave esp with a tall street gear
Tried their old line of extreme 4x4 cams many yrs ago in a heavier car actially worked well (til it went flat). no real contribution here just thinking out loud, like seeing different idears.
gkull I hope you have AC

 

I also spec in my own cams. For those that aren't aware SBC cam specs are made for 350ci engines. Any deviation above that up to 454ci tame these cams and you need a bigger cam.

Another point is the power range of a cam. I have a bigger SBC and have a cam card that says 3000-8000RPM. Also I have and intake that specs 4000-8000RPM. ( As far as I remember)

Now this does not mean that it runs like crap below the specs. On the contrary my 427ci runs fine from 1500RPM and up. I run around town at RPM's well below the specs of the cam. It smooths out around 1400RPM and I can tool around town at this RPM.

So my suggestion is not to take what sound logical when selecting a cam but rely on someone who's been there, done that.

 

When you buy any roller cam it is worth spending a few extra buck and getting the billet steel with a sleeved on distributor gear.

One of the first cams in my79 L-82 was a crane marine cam. I knew how my L-282 cam ran. It was supposed to make max hp at 5500 rpm. With specs of: The L82 used a "modernized" version of the old 350HP cam, PN 3896962, with 222*/222* Duration @ .050"; .450"/.460" lift and 114* LSA.

I was also installing bigger 64 cc heads to increase C/R along with headers and true duals.

I wanted a little more cam, but something I could drive 10,000 miles a year.

 

To each his own, it really depends on what an owner is going to do with his car. As an example "ME"
I did not want a race car, I wanted an around town car that sounded mean, I am 70 years old and have had my Vett for 40 years. In my youth H/P AND speeds were my thing, ( and tickets ) now it slow and loud. I'm like the old bull with his young son on top of the hill looking down on all the young heifers in the field , the young son says to his dad let's " run " down and x#%$& one , the old bull says to his son let's walk down and do them all.
So its what you plan on doing with your car , than you pick your can , don't take me wrong my car is fast with lots of low end tourqe, but I will not win any top end races, but you will have a hell of a time keeping up with me from 0- 60 off the line. Gas mileage not so great around 10- 12 MPG. I have had 5 corvettes in my life pre C3s , compression ratings around 10.1 . I had this one built with 9-6.1 and its real happy eating 89 octain.
I would not change my can for anything. There are days that I am out in my car and never even hit 4th gear, its all around town driving slow and loud. LOL.

 

This is one thing everyone should do. A few years back when I was spec'ing in a cam for my 427ci I called Comp Cams and gave them all the numbers ( you see at the end of cam ).

It was basically an Xr286R solid roller with a few duration and lift changes and I ordered a billet cam with pressed on iron gear. I also ordered a small base circle. The cam I got was a work of art At the time all this cost me only $40 extra, not sure how much it costs now but it is still worth the money

 

That is sad MPG. Installing more efficient cams can really boost MPG. I went from crappy l-82 mpg ( I bought my 79 new and continue to improve it even today) Heads, headers, single plane intake, edl 750 carb, and Crane marine cam of higher lift and duration and my MPG went to over 21 mpg on trips.

it was so nice to go 500 miles between fill ups (25 gallon tank) TH350 and 3.55 rear end and the AC on all summer long. It gets to 110 in Las Vegas.

my worst MPG vehicle is my 2007 4X4 Expedition @ 17.4 mpg. It gets better mpg now than when I first got it because I have an additional power chip hooked into the ECM and the K&N 102 MM throttle body and intake system

 

I wasn't complaining about my gas mileage, in fact I would not trade my low end performance or the cam lope sound for better mileage, I have 5 other autos for that, in fact 4 of my other auto , two Motor homes and a 4x4 get around the same MPG. I do have a scion that my wife drives if I want better long range MPG.
As I stated before it's all up to what he operator is looking for.
I will stick with my k12-422-8 cam. I think that if I could keep my foot off of the gas pedal more on the 0-60
take offs it would improve. LOL