Lunati 60406 vs PurpleShaft P4452761

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71duster06

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I was looking at the Lunati cam for a future upgrade but it looks very similar to my existing Purple Shaft cam. Only noticable difference is the intake/exhaust lift
Take a look at the following spec and let me know if this is even a worth while upgrade. Thanks

Lunati spec on the left vs Purple Shaft on the right

Intake duration @ 050 inch lift
226-----228
Exhaust duration @ 050 inch lift
234-----231
Advertised duration (intake)
268-----268
Advertised duration (exhaust)
276-----272
Intake valve life with factory rocker ratio
.494 in-----.450 in
Exhaust valve life with factory rocker ratio
.513 in-----.455 in
Lobe separation (degrees)
110-----110
 
I dont know what motor you have but i have that purple cam in my 340 and it is a dog down low and not a lot better up top I plan on replacing it the next time the motor is out of the car.
I see your from West MI ever take your car to Martin?
 
It'll perform extremely close but better than the Purple cam now. The biggest key here is cylinder head flow and the abilty to accpet the lift of the new cam. Also, at .494 lift, a bowl porting is a real nice plus.

The extra spread in durations are also a plus. The stock head or bowl ported head to a lesser extent (hopefuly) has a not so great balance ratio between them. The extra exhaust help the engine breath in better and fresher air and fuel charge. More of the incoming charge is fresher since more exhaust is exiting out. This is like adding intake duration without the penalty of adding rpm to the operation.

Due not that the difference will be mild and the butt dyno may not think much of, if at all, about any gain worth talking about. But also relize that it should very well be a more effiecnt engine making more power. Tune it well. I'd bet you'll use less gas as well.
 
I dont know what motor you have but i have that purple cam in my 340 and it is a dog down low and not a lot better up top I plan on replacing it the next time the motor is out of the car.
I see your from West MI ever take your car to Martin?

Yes, I try to get to Martin 5 or 6 times a year. I live in Lowell, MI now.

My engine is a 1970 340 out of a 70' Cuda. High compression.
 
What does it run right now? I try to go to a few of the midnight madness events each year, maybe ill see you there. Also with that cam i think you will need to get the heads cut for springs, who do you use for machine shop work around here? sorry to kinda hijack
 
What does it run right now? I try to go to a few of the midnight madness events each year, maybe ill see you there. Also with that cam i think you will need to get the heads cut for springs, who do you use for machine shop work around here? sorry to kinda hijack

Hoping for mid-high 12's. Have yet to get there.

The machine shop I use is Renew Performance Machine shop in Greenville, MI.

Also I try and get to the midnight madness as frequent as I can too. Ill look for you this year.
 
I have that Lunati cam in my '74 Duster, I'm quite happy with it. A little on the mild side, but not a bad cam. My next cam is going to be more radical.
 
The Hughes is a bit larger cam than the MP. Remember, the lift affects the curtain area along with duration. If you have 226°@.050 on the hughes, but it has to lift the valve an extra .044", there will be a much larger window for the air to enter through. Not to mention the Lunati will have a much faster rate of lift over the MP which is not apparent on the published specs.
 
The Hughes is a bit larger cam than the MP. Remember, the lift affects the curtain area along with duration. If you have 226°@.050 on the hughes, but it has to lift the valve an extra .044", there will be a much larger window for the air to enter through. Not to mention the Lunati will have a much faster rate of lift over the MP which is not apparent on the published specs.

So is the Lunati and Hughes cam similar in spec?
 
Sorry...lol. The LUNATI is bigger. Hughes has no dog in this fight...lol I'm just being a moron...
 
Try to get the duration at .200 numbers for both to help tell more of the story.
 
Keep in mind if you do not degree a cam, it will be possible for it to be installed pretty much anywhere. I've had one that was 11 degrees retarded dot to dot. What do you think that would have done for performance?

Also, you cannot really compare those two cams and here is why. That purple cam is ground using the Mopar .903 lifter as a reference for the lobe design. The Lunati is not. They use generic Chevy lobes on those cams. So to try and compare anything with a Chevy lobe to something that's ground specifically for a Mopar really shows you nothing.

I'll say this. That particular purple cam was one of the best street cams in the purple cam lineup. Installed correctly, it would run fantastic. Just because something is old doesn't mean it's bad.
 
Keep in mind if you do not degree a cam, it will be possible for it to be installed pretty much anywhere. I've had one that was 11 degrees retarded dot to dot. What do you think that would have done for performance?

Also, you cannot really compare those two cams and here is why. That purple cam is ground using the Mopar .903 lifter as a reference for the lobe design. The Lunati is not. They use generic Chevy lobes on those cams. So to try and compare anything with a Chevy lobe to something that's ground specifically for a Mopar really shows you nothing.

I'll say this. That particular purple cam was one of the best street cams in the purple cam lineup. Installed correctly, it would run fantastic. Just because something is old doesn't mean it's bad.
I ran on in the 340 in my challenger. 3.55 gear, 340 high stall converter, headers, and a performer intake. It was a lot of fun. For an engine that had stockish J heads with 2.02 valves that had peak flow at about .450 it worked well. If someone is going to upgrade the heads then another cam would work better with the combo.
 
It's also worth noting that sometimes extra lift won't make a big difference in power. There's some pretty interesting Dyno testing out there comparing low and high lift versions of the same cam and power levels being within margin of error.
 
It's also worth noting that sometimes extra lift won't make a big difference in power. There's some pretty interesting Dyno testing out there comparing low and high lift versions of the same cam and power levels being within margin of error.
And too, more lift is where you run into the extra cost for more costly valve springs and sometimes the machine work necessary to enlarge the spring seats for the bigger diameter. I would venture to say 90% of street builds don't really need anything much over .480 lift. Especially if still retaining stock iron heads.
 
Keep in mind if you do not degree a cam, it will be possible for it to be installed pretty much anywhere. I've had one that was 11 degrees retarded dot to dot. What do you think that would have done for performance?

Also, you cannot really compare those two cams and here is why. That purple cam is ground using the Mopar .903 lifter as a reference for the lobe design. The Lunati is not. They use generic Chevy lobes on those cams. So to try and compare anything with a Chevy lobe to something that's ground specifically for a Mopar really shows you nothing.

I'll say this. That particular purple cam was one of the best street cams in the purple cam lineup. Installed correctly, it would run fantastic. Just because something is old doesn't mean it's bad.

No sir, Lunati does not use Chevy lobes. Their cams are based on the .903 lifter.
 
Are they? Then my apologies. I stand corrected if that's true.

Well, they were when I bought the 60404 that’s in the 340 in my Duster and the 60403 that’s in the 318 for my Dart.

The Lunati’s have faster ramps than the purple cams did, higher lift on similar durations. That would be really tough on a narrower lobe.
 
Well, they were when I bought the 60404 that’s in the 340 in my Duster and the 60403 that’s in the 318 for my Dart.

The Lunati’s have faster ramps than the purple cams did, higher lift on similar durations. That would be really tough on a narrower lobe.
I know the Voodoo line is more aggressive, but I was unaware they actually used Mopar lobes.
 
I know the Voodoo line is more aggressive, but I was unaware they actually used Mopar lobes.
Yep,
UD Harold design for the .903 lifter
Asymmetrical lobes.
Faster opening , slower Closing
Then Comp XE line.
That Are on a Chevy lobe.
The Voodoo line is Quieter too.
 
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