What cam would you run?

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73Scamp318

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I've decided that I want to do a cam change on my Duster. What cam would you run? I'm looking to get into the 11s and it runs solid 12.20s @ 110ish now.

Here's the current setup:
74 Duster, guesstimated weight of 3300 to 3400 with driver
'71 360, .060 over, 10.2:1 CR
Edelbrock Performer RPM heads, OOTB
Edelbrock Performer RPM intake, as cast
Hughes 1.6 ratio rockers
Holley 750 DP
1 5/8" cheapie headers
Torqueflite 727,TCI Streetfighter valve body, PTC 9.5" converter flashes to 4400
4.30 gears, 28x9" slicks
Current cam: Edelbrock Performer RPM

Part #: #7177

Vehicle Type: CHRYSLER

Engine Application: 318-340-360 V8

RPM Range: 1500-6500

DURATION AS ADVERTISED INTAKE: 308° EXHAUST: 318°
DURATION @ .050 INTAKE: 234° EXHAUST: 244°
LIFT @ CAM (Lobe) INTAKE: 0.325" EXHAUST: 0.34"
LIFT @ VALVE INTAKE: 0.488" EXHAUST: 0.51"
LOBE SEPERATION: 112° INTAKE CENTERLINE: 107° IDLE VACUUM @ 1000 RPM: 10"

The information below is for verification of
opening and closing events.
INTAKE TIMING @ .050" LIFT: Opens: 10° BTDC
Closes: 44° ABDC
EXHAUST TIMING @ .050" LIFT: Opens: 59° BBDC
Closes: 5° ATDC

Posted via Topify using iPhone/iPad
 
Do you want to stay with hydraulic cams or change over to solid lifters?
 
RustyRatRod- I was was looking at the next step down on that cam line as one of the front runners and have heard nothing but good things about the Voodoo cams. I'd wind up with around .590" lift with the 1.6 rockers on that one.

70aarcuda- A hydraulic would make my life easier, since I shouldn't need to dig up new pushrods, but I'm not against running a solid cam.
 
Not for nothing, BUT, you may end up with new pushrods anyway since the cam is getting a little big at this point. IMHO, change over to a solid cam and run 1.6 rockers.

I think Tony has you covered since most of his rides are in the 10's.
 
If the new cam requires another set of pushrods, I won't sweat over it. I'm planning on putting on new springs with the new cam, at the least. Any specific recommendations for a solid?
 
I think, given this is primarilly a race car going by the parts you have - that the better choice would be a solid flat tappet, single pattern, with at least 250° @ .050 and lift in the .550 range (with 1.5 rockers). A hydraulic will be struggling with the springs you'll need and frankly - you'll be buying lifters, springs, and probably pushrods anyway. You're doing very well as it sits - but expect to need to have the convertor adjusted too.
 
You could go with a large hydraulic if you used the Rhoads VMax lifters. Those bastards will rev to 9K.
 
Engle KV-3

252/252 @ .050 .575 lift with 1.5 rockers...
 
I think I should say that this isn't a full blown race car. I do drive it on the street more than the strip.

Do I need to ditch the 1.6 rockers? I'd rather not if I don't have to... How much lift can I get away with before I need to pull the heads and have them reworked?

I've been mulling over having the converter restalled at some point, I guess this would be the push to get it done.
 
You wanna go flat or roller? Remember a roller brings you into the power curve sooner and keeps you there longer vs a flat tappet cam
 
Keep the 1.6 rockers. Considering the geometry of the small block and such, the 1.6 rockers will give you the lift at the rockers the cam is advertised at or real close to it. It also adds a slight bit more intencity to the cam.

Due not that the solid cams vs. the Hyd. cams are approx 10*'s larger for the same performance window.
 
Believe me, I'd love to go roller. It's just too large of an investment for me at this time, so I'm stuck with a flat tappet.

I'm also stuck with the converter I have. I don't think it'd cost too much to send it in to PTC and have them adjust the stall, but dropping the coin on a new converter is out of the question and I don't know how much further I can go with the 9.5". I'll have to drop them a line and pick their brains a bit...

I was hoping for just a cam and spring change, but I have the feeling it's going to be more extensive.
 
I think you might just get away with it. Your looking at .20 to get where you want to be. Your converters flash is 4400? You say? Also perhaps a on h drop in tire diameter for a little more finish line rpm?

Since a converter is pricey, even if it sent to be adjusted by the manufacturer for less money than new, try the other things first before the converter comes out. Figure that can wait until winter.

Everything else can be done sooner.
 
The RPMs are good the way they are for a lot more cam than you have - but there's no point in going any bigger unless and until they get ported. I would suggest that an 8" convertor would be a much better choice given the weight and gearing, and will hit harder and be more efficient (slip less) in high gear than the 9.5. You might ask PTC about trading that one in.
As far as the rockers go - I like using 1.5 rockers. Some disagree but I'd rather get the cam I want rather than worry about the issues with more ratio. The cams I would like for this are larger and the 1.6 starts to really push the lift beyond where it helps any and it's harder to find a duration in a cheaper non-custom grind to get the .540ish lift at the valve and still have decent duration. Ratio does not do much in terms of changing duration figures.
 
Call Hughes Engines they can recommend you the best cam for your combo. I have had good results when using one of their cams they recommended. They also have good customer service.
 
This may seem like a 180 from where I'm talking about heading, but I figured I might bounce it off of you guys since we're talking about cams...what about advancing the cam that's in there 4 degrees? I installed it per the cam card and, if I remember right, it came up at 107.5 ICL when I degreed it, so I left it alone. I'd have to dig through my notes to be sure though.

I've attached a screenshot of one of my LM-2 logs to show how the car currently runs. You can see after leaving the line at 2k, it hangs around 4300 to 4500 briefly, then takes off.
 

Attachments

  • LM2_log.jpg
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Hey Scamp318. Sorry to interrupt, I'm gonna have to look you up if you're going to the Mopar meet at CF Raceway in a couple weeks. toolmanmike
 
That's when the convertor is flashing.. The car doesn't accelerate much nor do the rpms climb when it's getting closer to it's stall. A smaller diameter unit would have less of a gentle climb during that time because it hits harder.
 
Hey toolman, I'm planning on going and I'll see you there.

Thanks for the info moper. Going off of that, it looks like I could probably pick up at least a little with a smaller diameter converter with a higher stall.
 
73Scamp318 said:
I've decided that I want to do a cam change on my Duster. What cam would you run? I'm looking to get into the 11s and it runs solid 12.20s @ 110ish now.

Here's the current setup:
74 Duster, guesstimated weight of 3300 to 3400 with driver
'71 360, .060 over, 10.2:1 CR
Edelbrock Performer RPM heads, OOTB
Edelbrock Performer RPM intake, as cast
Hughes 1.6 ratio rockers
Holley 750 DP
1 5/8" cheapie headers
Torqueflite 727,TCI Streetfighter valve body, PTC 9.5" converter flashes to 4400
4.30 gears, 28x9" slicks
Current cam: Edelbrock Performer RPM

Part #: #7177

Vehicle Type: CHRYSLER

Engine Application: 318-340-360 V8

RPM Range: 1500-6500

DURATION AS ADVERTISED INTAKE: 308° EXHAUST: 318°
DURATION @ .050 INTAKE: 234° EXHAUST: 244°
LIFT @ CAM (Lobe) INTAKE: 0.325" EXHAUST: 0.34"
LIFT @ VALVE INTAKE: 0.488" EXHAUST: 0.51"
LOBE SEPERATION: 112° INTAKE CENTERLINE: 107° IDLE VACUUM @ 1000 RPM: 10"

The information below is for verification of
opening and closing events.
INTAKE TIMING @ .050" LIFT: Opens: 10° BTDC
Closes: 44° ABDC
EXHAUST TIMING @ .050" LIFT: Opens: 59° BBDC
Closes: 5° ATDC

Posted via Topify using iPhone/iPad
Click to expand...
Any cam would be an improvement over that garbage grind. Call Tim @ Bullet cams or PM me and I'll pick you up a bunch.
 
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