I am going to rebuilding a late 60's 427 for strictly street use. I can get a deal on this cam. Any thoughts as to how this will compare to the stock cam that came with a 390 HP 427?

http://www.lunatipower.com/Product.aspx?id=2149


Lunati cam
Part # 06201
Grind # HI-262
Hyd. Flat tappet

Duration @ .006 = 262/262
@ .050 = 202/202
Lift w/1.7 = .445/.445
Lobe separation 112
Intake center line 108

 

Might be ok for a truck or low performance vehicle, but for a BBC corvette, you will want a duration of 225 to 240 for medium performance; go bigger if high performance.

 

Yeah go bigger, something in the .520-.540 lift range.
Your stock cam is .461/.480 so this cam is even milder than stock.

 

Thanks that is what I need to know. Wasn't sure what the stock cam was.

 

Just so you have all the data on it for comparison, the stock cam is 214*/218* @ .050 (268*/274* adv) X .461"/.480" w/115 LSA.

 

On my 1970 big block, i went with a Lunati 232/242 at .050 , .575/.595 lift, 112 lsa Cam. There is a slight lope at idle . If you dont want a lope, Id not go over 215 duration.

 

How much compression are you planning to run?
The more compression the more cam you need to bleed of some pressure to run pump gas!

I am running a 60203 with 9/1 comp 1,800-6200rpm, 227-233*, .542 & .554 lift. Being a strickly street car I sometimes wish I had gone for the 60202. That's what I'd recommend depending on the rest of your configuration.

http://www.lunatipower.com/ProductGr...?id=287&cid=56

 

srx6, Does your car have a lope to it with that 60203?

 

What does lope mean?

 

in Laymans terms, the Lope refers to the idle quality of the engine (affecting the entire car) , or the amount it shakes at idle , simply put. The higher the duration camshaft in degrees, the more unsteadyness youll notice from the engine at idle. On my 454 cid Street motor, Im running a 232/242 duration at .050" and since its a Big Block, its not an objectionable unsteadyness at idle for me ; but having that same duration in a small block engine , it would be much more noticable. Also, the LSA (Lobe Seperation Angle) ground into the camshaft affects the idle quality as well --- the lower the number (ie: 108) would produce a poorer idle quality than a larger number LSA (ie: 114). This is why i mentioned earlier that a cam larger than approx. 215 degrees duration in your small block engine might very well be objectionable to you regarding how much the lope is. , especially if its used for 100 percent street driving. (Plus, people you pull up alongside at a traffic light will look at your car and think theres something wrong with it if its sitting there rockin' back and forth <<<< not a cool thing for a snazzy looking Corvette . The look on thier faces would resemble this >>>> ...lol....

 

P.S.,,, oopppss, sorry, I confused you with another Poster , but, the jist of my post above still stands. Regards.

 

i have a 69 427/390hp and love feeling that engine shake with that ticka-ticka-ticka sound. My engine is for the street only during the summer with stock carb and exhaust manifolds but I do want an aggresive unsteady cam. What should I be looking for in a cam? Thanks for the info

 

Your joking, right?
A ton of the people that want to change cams want to do it just to get that kind of idle.
Heck, Comp developed a whole line of cams [Thumper] just for the purpose of getting that idle.
Have you ever heard an LS6 idle. Its not smooth, but very cool.

 

Among others, I'd suggest looking into CompCams Xtreme Energy line of hydraulic flat tappet grinds, but which one depends a lot on your CR and trans. These cams are far more aggressive designs than the stock stick, with significantly higher lift for given durations and much closer LSA's. The right one (perhaps the XE268H: 268*/280* adv, 224*/230* @ .050", .515"/.520", 110* LSA) ought to go thumpity-thump enough to float your boat and strain your neck.

 

Haven't figured out what I want to do for CR but certainly want to run pump gas. Muncie 4speed and currently has a 373 rear end but I also have a 308 set of rear gears. It will be a month or two before I get the block over to my engine builder and we will see what it needs. I assume I will have to put pistons in so I have a lot of choices. Yes a nice lope is always welcome, will only be street driven as I have my racing toy already.

 

No, im not kidding ; ive actually seen the look on motorists faces at a stop light when ive been in a car with a high duration/high lift cam ; thier face looks like >> or >>> ! Im not disputing some guys go for the rumpity, rumpity, rumpity, rump of a snotty-a__ little cam ... in fact, I lean a bit to that side myself. I confused the OP with another thread whos Poster was talking about wanting a cam for the street , so, my mistake for that error.

 

Yes, you can definately tell there's a cam in it, yet it draws lots of vacumm at idle to run brakes.

For questionable pump gas now days I'd recommend no more than 10/1 with the 60203 cam & my choice for a street cruiser would be 9/1 comp with the 60202 cam. They will both work good with stock exhaust manifolds, stock intake & quadrojet! 3.73s would be a great in-town gear with either combo but I would recommend second combo for the 308s.
JMHO
Just My Humble Opinion

 

Those poor people don't know what they are missing.
When I pull up to a car at a stop light that sounds like that I will turn
down the radio and roll down the windows just to listen to it.
If it turns out the car is burning race gas too, I am in pure heaven.

 

RobRace10, if your Muncie is a close ratio box I wouldn't advise putting the 3.08 FDR behind it, as the 3.73 was the tallest gear the factory saw fit to match with that gearset. Even if it's a wide ratio box, with that 3.08 you'd need to run a cam tailored more for bottom end torque, which would tend to require lower CR's due to the typically shorter durations of such cams. IMHO the better torque multiplication of the 3.73 would allow you to shift the power curve upwards with a higher CR/longer duration combo which wouldn't run out of steam just when things start getting interesting. Think in terms of matching the entire system, as the engine doesn't operate in a bubble, and the decision ought to come easier.



Sidebar: Beauty is in the ear of the beholder...

Once pulled up to a light next to an ASE certified mechanic (could see the patch on his shirt) who told me I had best get straight to a shop to fix the bearing in my AC compressor. I just said thanks and left him with his jaw hanging as the light changed, gear drive noise and all. I've had others tell me they thought a Harley had pulled up until they looked around and saw my shark instead. I tell them thanks for the compliment. It's the same as with music; what's a symphony to some is just noise to others, and as long as I'm enjoying the "concert" I don't care what some boob may think who hasn't a clue.

 

I think the Z06 sounds like an electric motor but then I think
a cam with 90 degrees overlap is a street cam.