Is a MP 509, 292 purple shaft a decent cam on a supercharged motor

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hemichuck

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I’ve got a 360 long block that’s built but never ran yet, it’s got the Mopar Performance 509/292 can in it. I was wondering if it would work on a supercharged application (B&M blower) or should I change to another grind
 
There is always a better grind, always.

If you go with that cam (because you have it already?) I hope it is the one on a 112 and not the 108 center line.
 
What does the rest of the combination consist of? If it actually has enough compression for the engine to properly work with that cam (at least 10.5:1, maybe even more!), then it’s not going to work too well with a blower.
Well, there are ways to do it, but it requires something more than most typical 360 long blocks floating around out there....
 
What does the rest of the combination consist of? If it actually has enough compression for the engine to properly work with that cam (at least 10.5:1, maybe even more!), then it’s not going to work too well with a blower.
Well, there are ways to do it, but it requires something more than most typical 360 long blocks floating around out there....
Good point but possibly the horse before the cart here.
 
76* of overlap on the 108 version is a long long time to be blowing gas and air straight across the piston and out into the header pipes. What if it catches fire in there?
Many supercharged or big nitrous hit engines make the headers glow, but I bet that cam would make them melt out from under the car..
 
I’ve got a 360 long block that’s built but never ran yet, it’s got the Mopar Performance 509/292 can in it. I was wondering if it would work on a supercharged application (B&M blower) or should I change to another grind

This cam would make an excellent cam for a streetable blown small block. Especially for the price. Summit Racing® Classic Cam and Lifter Kits SUM-K6901

If you want something a bit "bigger", try something more like this one. Summit Racing® Cam Kits SUM-K50062

Interestingly, this second camshaft has the same lobe separation and duration as the wildly popular "sloppy stage 2" cam in the LS world. Which may be useful if you want an idea how it might idle.

There are a number of articles on blown old-school brand x v8's with custom camshafts that spec somewhere around 234/232 on 114 LSA.
This is what i plan to do for my own supercharged 360. There doesn't seem to be anything like this as an off-the-shelf cam.
 
76* of overlap on the 108 version is a long long time to be blowing gas and air straight across the piston and out into the header pipes. What if it catches fire in there?
It already happens. It doesn’t need to be supercharged to do that. Baseless worry....
Many supercharged or big nitrous hit engines make the headers glow, but I bet that cam would make them melt out from under the car..
Never happen
 
Ok, so I ran an old school MP crate 360 short block that had 9.5:1CR and the .509 cam with the 108 LSA.
I also ran a B&M 174 blower at 6PSI and at the time a 75 shot of N2O.
I had 451hp and 589tq at the rear tires.
While there was an insane amount of torque off the line (3:55 gears) the combo was as expected, totally mismatched. I had to run an extremely small upper blower pulley to get 6PSI of boost due to the overlap.....
I’d be spinning the blower well over B&Ms max rated rpm.... That simply beat the **** out of the air and created an undesirable overheated intake charge. Using the smallest blower pulley also resulted in belt slip as there was little surface area for belt grip (6 rib pulley)...

My uncoated headers wouldn’t be glowing cherry red but there was a great amount of under hood heat. Damn floor boards were super hot as well!

Go with a wide LSA (114) and I’d recommend a 10 rib pulley setup.

I’d also run 360* full groove main bearings to provide full time oiling to the rod bearings.
 
Rumblefish, I don’t know which centerline it is, it’s the one that came in the short block. I’ve got the actual B&M cam that they sold with the blowers, it’s like 441 lift with 276 duration, pretty much equivalent to a 68- 340 4 speed cam. I thought it was pretty mild. I might just pop the 509 out and use the B&M cam, it’s going in my sons Dakota convertible.
 
MiradaMegaCab, thanks for your reply, that’s the kind of real world experience I was hoping to hear. Sounds like it’s not the best choice of cam.
 
turbos and blower cams are pretty small compared to NA power cams. Also compression needs to be addressed to fully utilize forced induction.
 
Rumblefish, I don’t know which centerline it is, it’s the one that came in the short block. I’ve got the actual B&M cam that they sold with the blowers, it’s like 441 lift with 276 duration, pretty much equivalent to a 68- 340 4 speed cam. I thought it was pretty mild. I might just pop the 509 out and use the B&M cam, it’s going in my sons Dakota convertible.
IF that is a crate engine, It ain’t a MoPar crate engine.
I’d run the other cam in a second flat. The 292 Purple cam is more than likely to be on the 108.

I think they put that 292 cam in the 380 hp crate motors ..... which were independently tested at ~400hp,IIRC
Almost right; the 380s had a 288/292/108 and 9/1 SCR
The early crate engines were the 360/300 & the 360/360. I forget what the 300/360 had for a cam. But the 360/360 -*IIRC*- used the MP Purple 284/.484 Hyd. cam. I gave away all my old books to friends and old club members. So I cannot check for the particulars.

That cam you list is for the roller cam 360/380 crate engine. I’m not 100% sure they used the Hyd. 292.
It is a good bracket cam. Very basic, performs well, even with stock heads though a good gasket matching and more importantly a bowl porting really help that low .509 lift cam to go. The cam seems to like a good bit of compression. But bad for adding pressure. If it was his only cam and was ready to run I’d just say use it, or, IMO, better yet, sell it and roll the money over into a better cam.

I still think the MP Purple cams are good for brackets. Not a big fan of “that” one in the street. BTDT, not thrilling unless it was at WOT. Even worse in a heavy E body.
 
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IF that is a crate engine, It ain’t a MoPar crate engine.
I’d run the other cam in a second flat. The 292 Purple cam is more than likely to be on the 108.


The early crate engines were the 360/300 & the 360/360. I forget what the 300/360 had for a cam. But the 360/360 -*IIRC*- used the MP Purple 284/.484 Hyd. cam. I gave away all my old books to friends and old club members. So I cannot check for the particulars.

That cam you list is for the roller cam 360/380 crate engine. I’m not 100% sure they used the Hyd. 292.
It is a good bracket cam. Very basic, performs well, even with stock heads though a good gasket matching and more importantly a bowl porting really help that low .509 lift cam to go. The cam seems to like a good bit of compression. But bad for adding pressure. If it was his only cam and was ready to run I’d just say use it, or, IMO, better yet, sell it and roll the money over into a better cam.

I still think the MP Purple cams are good for brackets. Not a big fan of “that” one in the street. BTDT, not thrilling unless it was at WOT. Even worse in a heavy E body.
I’m starting to rethink this whole project about now. The 360 crate motor is a 509/292 flat tappet and since the motor is most of the way together I might just go ahead and drop it in my old Duster bracket car (naturally aspirated) and use one of my magnum based 408 short blocks to build my son a truck motor. I have 2 408 Magnum short blocks that were built for a supercharger so the only obstacle I have to get around is a magnum style head with LA intake bolt pattern. I’ve got some EQ heads that’ll solve that problem. I’ve got 4 or 5 Magnum roller cams that have better profiles for blowers. Plus the Magnum short blocks are forged piston and cranks, wasn’t certain about supercharging a crate motor with Hypereutectic pistons anyway.
 
^^^BEST OPTION YET!^^^ That’s perfect, just follow the advice on the drive pulley and belt and make it breathe. What are your specs on your custom blown magnum cam grinds?
 
I’m starting to rethink this whole project about now. The 360 crate motor is a 509/292 flat tappet and since the motor is most of the way together I might just go ahead and drop it in my old Duster bracket car (naturally aspirated) and use one of my magnum based 408 short blocks to build my son a truck motor. I have 2 408 Magnum short blocks that were built for a supercharger so the only obstacle I have to get around is a magnum style head with LA intake bolt pattern. I’ve got some EQ heads that’ll solve that problem. I’ve got 4 or 5 Magnum roller cams that have better profiles for blowers. Plus the Magnum short blocks are forged piston and cranks, wasn’t certain about supercharging a crate motor with Hypereutectic pistons anyway.
I like your thinking....
It’ll be detonation that will kill the hypers, not the boost pressure.
It was asked before, but, what is that 360’s compression ratio?
 
^^^BEST OPTION YET!^^^ That’s perfect, just follow the advice on the drive pulley and belt and make it breathe. What are your specs on your custom blown magnum cam grinds?

FB47CF42-04B7-4898-A7A3-6A4B8F3D632D.jpeg
 
A possible option is if you change to the EQ heads you may be able to a thicker head gasket to drop compression some. If the micro finish isn’t at spec for cometic MLS head gaskets, SCE has some options that may be viable. That cam is a healthy torque builder for a boosted engine.
 
As others have said - a supercharger cam is better suited to be on a wider LSA and less overlap than an NA camshaft. I am going to be running a cam on a 114* LSA with around 290/300 Duration - but it is a lazy grind so duration at .050" is fairly mild.

Should run very well on the street with my 8-71.
 
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