This cam appeals to me. What do you think? I am hoping the 540 and blower tame it down, Even if it states .714 lift after setting lash it will be about .680
The lash setting of .020 appeals to me. It makes for a quieter operation


CRN-138131 $319.95
Estimated Ship Date: Tomorrow
Warnings Application Warranty Show All

Brand: Crane Cams
Product Line: Crane Racing Camshafts
Cam Style: Mechanical roller tappet
Basic Operating RPM Range: 4,200-7,800 RPM
Intake Duration at 050 inch Lift: 262
Exhaust Duration at 050 inch Lift: 270
Duration at 050 inch Lift: 262 int./270 exh.
Advertised Intake Duration: 294
Advertised Exhaust Duration: 302
Advertised Duration: 294 int./302 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.714 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.714 in.
Valve Lift with Factory Rocker Arm Ratio: 0.714 int./0.714 exh. lift
Lobe Separation (degrees): 114
Intake Valve Lash: 0.020 in.
Exhaust Valve Lash: 0.020 in.
Computer Controlled Compatible: No
Grind Number: R-262/420-2S1-14 IG
Quantity: Sold individually.
Notes: Requires cam button spacer. Camshaft incorporates an integral cast iron distributor drive gear. Aluminum-bronze distributor drive gear not required. Also fits Rodeck 481 aluminum engines.

Camshaft, Solid Roller Tappet, Advertised Duration 294/302, Lift .714/.714, Chevy, Big Block, Each

 

Yup, that will work. If it were me I might go a little more duration and less lift, but it is certainly in the ballpark. Good luck Norval

 

the 114 lsa will tame it with around 500 cubes. It should be fine at 540.
-Scott

 

That will run pretty sweet. It will have a little thump at idle..but nothing crazy. I just "heard" the street roller cam the other day in a tunnel ram 454 with rect port iron heads. It's the # 138641 262/270 on a 114 with .632 lift. It actually sounded pretty tough when it fired up and idled clean even with the tunnel ram and 2x750's and around 10.0 compression. His "street roller" has a lot more adv duration and I expect yours will sound even mellower than his.

He runs it in a street rod deal and it hits 10.80's@123 with 4.10 gears. That seems a little down...so I think he has some mismatching issues with cam/heads etc considering his car is very light.

Yours is based on the old R262 lobes. That one and the R268 have been "stds" of the world for a long time. Those are proven lobes and should do very well. Crane usually has reliable lobes..not crazy stuff.

I had that Engle 262/273 in mine on a 112 LSA with .672/.675 lift. It peaked Hp at 6200 rpm and TQ @ 4600 or so. When I capped it up in the car, interestingly it still peaked HP at the same rpm, but TQ peak dropped to 4300 rpm. It sill made 615 RWHP uncapped with unported heads, small intake and 10.5 compression. It idled very clean and I expect yours will do the same or better with wider LSA and blower.

You are getting the iron cam gear..good deal. No issues there.


JIM

 

It will be interesting to see if the blower lowers the peak hp and tq rpm #'s....a little like nitrous does.

 

John I agree on the less lift. Since this is a street machine and valve train life is important I would prefer a little less lift too.
Jim suggested an alternative and I am looking it up now. With it's less lift it looks like a better alternative

 

Jim that cam appeals to me even more with it's lower lift but same duration but check out the price?? It might be a mistake but I will phone for a price at 9 and if it is the same I will order it today
CRN-138641 $436.39
Estimated Ship Date: 9/28/06
Warnings Application Warranty Show All

Brand: Crane Cams
Product Line: Crane PowerMax Camshafts
Cam Style: Mechanical roller tappet
Basic Operating RPM Range: 3,800-7,400 RPM
Intake Duration at 050 inch Lift: 262
Exhaust Duration at 050 inch Lift: 270
Duration at 050 inch Lift: 262 int./270 exh.
Advertised Intake Duration: 312
Advertised Exhaust Duration: 320
Advertised Duration: 312 int./320 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.636 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.636 in.
Valve Lift with Factory Rocker Arm Ratio: 0.636 int./0.636 exh. lift
Lobe Separation (degrees): 114
Intake Valve Lash: 0.020 in.
Exhaust Valve Lash: 0.020 in.
Computer Controlled Compatible: No
Grind Number: SR-262/374-2S1-14 IG
Quantity: Sold individually.
Notes: Requires cam button spacer, camshaft incorporates an integral cast iron distributor drive gear, aluminum-bronze distributor drive gear not required. Also fits Rodeck 481 aluminum engines.

Camshaft, Solid Roller Tappet, Advertised Duration 312/320, Lift .636/.636, Chevy, Big Block, Each

 

John check out the other cam with it's lover lift. That is more appealing.
When I ran a nitrous motor with 340 cc intakes the heads were a dog below 5000 without nitrous. Once the blower was installed those same heads worked from idle on up. I hope the large cubic inch and the blower tame the low end torque down and yet allow the motor to breath.
What about the torrington bearing? In past motors I just drilled a 1/8th hole behind cam sprocket into the high pressure oil passage and ran the gear against the block. Being a roller it doesn't pull back against the block as hard.
I haven't drilled this hole yet and keep wondering about spending the extra and run a contained bearing behind the sprocket.
Is it worth the expense?? Since I run high pressure, high volume oil pump the loss of the extra oil doesn't concern me.
You can drill right into the oil passage that goes from the main to the cam bearing and bleed a little oil off behind the gear.

 

It's a done deal.. I just ordered the lower lift one of the 2, the one with .636 lift. It will be alot easier on the valve train. It cost $429 CDN but uses the stock distributor gear.
Thanks Jim drawing my attention to it and John for recommending the lower lift. I agree with you.

 

That cam should give you a lot of trouble free miles. I think that a 540 with an 8-71 is not going to ever have to worry about tq. I'll bet you will be very happy with the motor / tranny combination. I would like to drop your motor into my drag car and see what it would run.

 

Thanks John. The lower lift will be easier on parts and spring pressures are lower then the higher lift cam.
My new motor won't be much better then what you are running now. I thought you were also working on a bigger motor???
Your old cam also appealed to me.

 

I know that you already bought it. But it has been my racing experience that the sub 7600 rpm motors with sub .800 lift springs and valve train really hold together for years and it was the guys with over .800 lift and over 8000 rpm that were always breaking springs.

I would not have any qualms about running @.700 even with 2.300/1.90 if you used the lighter weight valves and possibly titanium retainers. it's rpm that kills the stuff and I don't imagine that your ever going to rev it up to 7000

 

I know I will never rev maybe to even 7000 anymore but I also worry about the roller lifters. I was under the impression when I bought mine 7 or more years ago that a roller would last forever then I join this forum and learn that I should be checking them yearly?? I really considered going back to flat tappet but then by WEAK springs are about 180 pounds installed at 2.100 and about 550 open with .600 lift and those would kill a flat tappet cam. Change springs?? Not really an option. My heads take the big springs , the what 1.625 or so and they just don't make soft springs in that diameter. To run just the single outers with no inner bothers me, running adapters for smaller springs again bothers me so i am stuck with these WEAK large spring.
I do run titanium retainers with the 2.3 valves
I am trying to be nice to my valve train and while I could make a quick phone call and change the cam to the .714 lift again I feel more comfortable with the .636 lift.
I am considering replacing my 308's which I love with 3.55 to allow the motor to cruize with a little more rpm. Right now I am 1250 at 50 and 1550 at 60. The new cam might not like those low rpms.

 

Never run a dual or triple with less springs or damper. The harmonics might just break a coil or go into float at some really low rpm.

I've got that one roller cam that used .008-.012 lash. Very quiet valve train. I turned my Comp suggested .020 -.022 down to .014 and it's amazingly quiet compared to how it was. Talk to the tech people about what the true minimum is with your lobe profile.

 

I was told I could go as much as .010 under on valve setting without a problem. I actually set my valves cold .006 tighter then the hot specs.
I agree with not running only part of a spring.
I am going back to crane this time

 

In a drag race only BBC I would have no issues with a .700++ lift cam either, but Norval wants to set up his valve train to be as trouble free as possible. A .700 lift cam is not going to last 5000 miles before it kills a lifter. You have to consider his car also, we are talking about a 540 in. 8-71 blown, small tire, 5 speed car. It will be severely traction limited with the "smaller" cam anyway. For the small amount of power he would gain compared to the valve train reliability he gives up, I think he made the right decision to go with the cam with less lift.

 

Running the combination I now have but with the 4.11 gears it was 4th gear before you could lean on it. At the top end of 3rd if you got a little too agressive the tires would go up and I actually went right around on the highway. A very scarey thing. Part of the reason for going to 308 was to kill off a little of 1st gear and at least make 3rd more usuable.
I find the car much faster off the line with the 308's. At least you don't shock the tires so much with the torque of 12 pounds of boost and a low gearing.
I too feel John is right in that my lower lift will cost me little with a blower and save the valve train.
Jim is also the guy who put me on to this particular cam with it's lower lift but same duration as the one I picked.
I am also glad it has the cast iron gear and can run the stock distributor gear.
Crank is in the block and ready to receive the pistons.

 

I always drill that same oil passage to lube gear. Works for me!!

That cam will be pretty street friendly and not hurt stuff. It has more adv duration so manners might not be as crisp in a N/A application, but again, I figure blower will help all of that. The guy I know has been running his a long time.

I did talk to a guy running a 8/71 blown 496 a few weeks ago with a flat tappet in it. He was running 9.70's@139-140 in a 3700 or so lb Camaro with big tires on the back. He went flat tappet for better reliability too.

So cam is ordered? Did you ever check with Engle? I bet my old one with the 262/273 on a 112 with the .672/.675 would have been a decent choice too.

Don't worry..you will have all you want with it. I saw a 502 with iron Merlin rectangular ports make 675 HP N/A with only 9.0 compression or so with that same series of Crane street roller. I think they had tighter LSA. You have more cubes, better heads by far and an 8/71...ought to be fun!!

JIM

 

Did I post on drilling this hole??? I drill a small hole into the oil passage that goes from the front main to the cam bearing. It is a short drill and puts presurized oil on the back of the cam gear. I must have posted on this or you wouldn't have mentioned it
A blower seems to cure everything. With instant boost anytime the throttles are popped open the boost is right there.
I looked at Eagle but our local speed shop deals mainly with Crane and Comp. I ran 6 crane's flat tappet before this comp roller and really never had a problem with comp. I went back to the old reliable source.
My 262/270 @ .050 is righ where I want to be in duration and about equal to yours and I know you run strong.

 

Norval Your super charger should cram the engine with plenty of air
with the lower lift cam. A non supercharged engine may need a
very highlift cam can't see where you would need it.