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-   -   Going down this road again Cam suggestion (https://forums.maxperformanceinc.com/forums/showthread.php?t=611592)

Nickv 09-23-2009 03:12 PM

Going down this road again Cam suggestion
 
Ok, I know I've been down this road again about changing out my cam in my 72 lemans convertible. Many suggested the Crower 90916 cam, which In fact I bought, I did not install it yet because after running some Dyno 2000 simulations comparing it to my current cam the Crane 272H, the 60916 seem to lose some low end and mid range horseppower and torque but gains in the upper rpm range. I'm thinking my car would actually be slower with the 60916 cam. I don't have a higher stall and only 3:23 rear, which I don't want to change out.

Here is my current setup again. I'm thinking a Hydraulic Roller would be the best choice.


400 +0.030
TRW pistions
Stock Rods with arp bolts
Stock crank with studs for the mains
72CC E-heads ported and polished. Overkill I know.
Edelbrock RPM instake
Holley 750DP carb
Crane roller rockers 1.65
Crane 272H cam currently in car
Heddman Hustler headers with 2.5”, flowmaster mufflers
CR is 10.2. Runs fine 93 octane pump gasoline
TH400 with shift kit.
3:23 10 bolt safe-t-track rearend


The car runs a 13.6@102MPH with street tire and a 2.1-2.2 60' time.

Any suggestions for a cam upgrade to provide some additional power?

Thanks!

ta man 09-23-2009 03:39 PM

You are currently undercammed for those heads.A roller cam would be an excellant choice.I'd guess something in the 225/235 range with as much lift as your heads can handle with a 110 to 112 lobe seperation would wake it up.You would be in the mid 12's easy with properly matched camshaft for your current combination.

PONTIAC DUDE 09-23-2009 03:41 PM

Yes a Custom hyd roller in the 230 range would run faster and still maintain great street manners.

Only change would be cam, lifters and pushrods.

Nickv 09-23-2009 03:48 PM

Wouldn't I have to change the valve springs on the E-heads? They are lunati springs not the springs that you would normally get with out of the box E-heads.

PONTIAC DUDE 09-23-2009 03:52 PM

Quote:

Originally Posted by Nickv (Post 3774757)
Wouldn't I have to change the valve springs on the E-heads? They are lunati springs not the springs that you would normally get with out of the box E-heads.

Need to know seat and open pressure......... (at the lift you are gonna end up with). Plus how much coil wire clearance at lift.

Nickv 09-23-2009 03:53 PM

How about a CompCam XR276HR?

Nickv 09-23-2009 03:54 PM

Quote:

Originally Posted by PONTIAC DUDE (Post 3774765)
Need to know seat and open pressure......... (at the lift you are gonna end up with). Plus how much coil wire clearance at lift.

I'd have to dig out the paperwork from the engine build. Not sure right now.

66bonne 09-23-2009 10:35 PM

Take the guess work out of it - just call P-Dude and he'll set you up with exactly what you need for your combo. I had one of his custom grinds in my Catalina and beat the dog-sh#t out of it at the strip and drove it on the street nearly every day.
Liked it so much that I ask him to set up a new hyd roller for my next motor.

Jim
Keefer's Nut Hugger

Cliff R 09-24-2009 05:03 AM

What torque converter are you using? This is the key player in what camshaft is going to work well with your combination. Unless you have some stall speed, a stock cam is probably going to outrun most any high performance cam you would purchase, at least on the first part of the track. Big cams are also horrible on the street, so a true steet car needs a cam that produces good vacuum at idle, and strong power right off idle.

With just over 10 to 1 SCR, the 60916 cam is a pretty good choice. With a good converter behind the engine, the larger 60243 cam would work even better......Cliff

Nickv 09-24-2009 11:49 AM

Quote:

Originally Posted by Cliff R (Post 3775242)
What torque converter are you using? This is the key player in what camshaft is going to work well with your combination. Unless you have some stall speed, a stock cam is probably going to outrun most any high performance cam you would purchase, at least on the first part of the track. Big cams are also horrible on the street, so a true steet car needs a cam that produces good vacuum at idle, and strong power right off idle.

With just over 10 to 1 SCR, the 60916 cam is a pretty good choice. With a good converter behind the engine, the larger 60243 cam would work even better......Cliff


Right now the car has a stock converter and 3.23 rear. I can change out the converter no big deal, but right now I want to keep the gears because it makes for a great highway driver.

If I were to go with a 2000-2500 stall converter with those read end gears would the 60916 cam work well?

Right now the car has great street driving manners with lots of torque. And like I said it runs a 13.6@102 right now as we speak.

David Jones 09-24-2009 12:27 PM

I run a small hyd roller in my 400. 220/224 @ .050 with .513/528 lift. It's a Comp Cam and P Dude ordered it for me 3-4 years ago.

400 .030 over.
Mildy ported #48 iron heads
TRW pistons (I'd figure more like 9.5-1 compression by what I've read with a 72cc chamber)
800cfm qjet I built
Factory iron manifold...gasket matched
Stock crank and rods.
1.5 Harland Sharp rockers
Dougs headers with 2.5 pipes and 20" super turbos
Stock T400 with an 11" PTC converter 2000/2300 stall
3.55 gear
Makes 15-16"vacuum and idles nicely at 725-750 rpm in gear. Just enough "bump" to say it's got a cam.

On a 2.12 60 ft (3-4 year old 255/60-15 Radial T/A's) it did 13.2 @ 105.5. With some traction it should be a 12.90 something car

I have the trans set to shift at 5200.

Get a 225/230ish Hyd roller. You'll like it.............

Cliff R 09-24-2009 09:11 PM

I agree, keep the gears, no need for any more gear than that. I use 3.42 gears, and a Continental 10" converter. Drives very much like a stock converter, you never really know it's there till you go to the track. Flashes to apprx 3400rpms with good traction, the rest is in the signature below.....Cliff


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