360-508 mopar cam builds

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I'll just say, using a smaller valve to mask the lack of low end with that cam is fruitless. You'll gain little down low, and limit the high end potential. Can you use them, yes.....would I look to go there with the .508", no. You'd be better off picking a modern grind to use with the 1.88's to build some big mid range torque.
 
Im alover the place I know.I need to get it all figured out.it would be nice if the magnum head on this build would be the rite choice
 
Ok well how much better would the comp cam pp292h its the purple plus says it replaces the mopar 508 cam
 
060 360 with shaved j heads. It was about 9-1 compression. The piston's were a .100 in the hole @ tdc. The car was a 71 duster street car with a four speed and a 4.10 gear. I was running the comp 305h with .525 lift it was very choppy at idle and produced great mid range power it even had a torker II intake. Anyways it ran 7.90-8.00's on pump gas in the 1/8 mile at 86 mph. Put a mopar .508 in it and slowed down.

I think youd be happier with the 292h cam. The 305h was really to much camshaft for my combo but it was .2 quicker than the .508 mopar cam.

I sent the .508 to bullet and had it reground as a solid and running stock j heads and 1.88 valves on a 11-1 340 in a 70 dart, 5.13 gear and 28x9 slicks it ran 7.68 at 91 mph. Them heads really suprised me for being stock unported.
 
I run the Mopar 380 HP 360 LA short block in my Demon race car. I comes with the 508/292 hydraulic flat tappet cam. The pistons are KB flat tops that are around .060 down in the hole, so the compression is about 9:1, maybe a tad higher. The car is setup to run pump gas, 91 octane. I run the Aerohead 340 X heads with the 2.02 intakes. The heads and short block have no work done to them, I just installed as delivered. I run the M1 single plane intake with a Proform 750 carb. The car is all steel, it weighs 3050 with me in it. It has a stock bucket seat only with no carpet, a 6 point roll bar.
On the chassis dyno, it put down 300 HP at 5400, and 314 TQ at 4600. This is a race car, not street driven. The car has 4.56 gears with 30" tall slicks. With a mild street converter, it ran 12.30s. With the present 8" 4600 stall converter, it runs 11.60s to 11.80s at 114 MPH depending on how hot it is outside. It 60fts 1.51, 1/8 7.30s at 92 MPH. I shift at 5500 to 5800 and go through the lights at 6000.
This cam is a bracket race cam, and it makes great torque from 3000 to 6000. However the 360 idles at 950 with 5" of manifold vacuum. A lot of people don't like this cam, but it is a fine race cam. Since you have it already, use it. Keep in mind that there are better cams out there, this one is old, but it was made to be easy on your valve gear. I have been running this for 3 years and have never pulled off the valve covers since I set the lash after break in.
The people are right that there are better street cams out there, this one has 78 degrees of overlap, which makes is sound badass at idle, but not as streetable as some newer grinds.
Sounds like you have picked better heads than I have, so your power may be higher, and run better at a higher RPM. But if you run the pistons at 0 deck, make sure you check valve clearance to the pistons, you will need to notch them. Advancing the cam may give you more clearance to the pistons, I did not degree mine, just left it where Ma Mopar put it.
Of course there are better parts out there, but what you have will work.
 
damn your car is light.i wanna run 28 tires 410 gears,3500 converter,0 deck 107,magnum heads stock or the iron rams,should have perfect quench,m1 or rpm air gap,or 340 victor intake,of coarse the 508 mopar cam,750 dp later will add better carb,maybe a 904,have ford 8.8 what i hear is less hp lost using it.alum radiator,water pump will be electrick,have power steering,non ac car,fuel cell in trunk,will make alum brace and use fiberglass matt and resin,should be lightest alternative.i may even cut floor up and use the fiberglass cloth and resin.im gonna replace front clip with one peice fiberglass or run fib fenders and hood,will change to 70-72 style.this is my toy not gonna drive on street unless i race it.ill adjust my mindset if someone thinks something wont be good idea.
 
im getting my 360 on friday,i may just install the mopar cam in it for now while i build onother 360. just for fun to c how it runs comparred to the combo im gonna run later with it.
 
scratch that idea,ill have plenty of fun with the 318 first.dont wanna waste money i dont have lol.
 
You can get the car light without cutting on it. My ride is all steel, the floors are stock except for mini tubs. Just remove the basics. Going from power steering to manual drops about 45 pounds. Remove the heater box, etc. I did remove the undercoating from the chassis. There is no fiberglass on mine. The windows are also stock. I also have Strange front disc brakes, they took 45 pounds off the front compared to the 9" drums.
 
The first motor that I ran in my D50 was a 380hp 360 but it was a magnum with the cam that came in it from the factory. .501/.513 hydralic roller cam. It was also 9 to 1 comp. stock everything. I ran a best 7.32 @ 94 mph, .513 gears, 30 in tall M/T Drag radials, 315/60 and 8 in convertor at 2950 lbs. I switched from a 9 1/2 convertor to a PTC 8 in and almost 10 and half. I would say the magnum heads work pretty good for a stock head. I have a Indy headed 340 in it now and it has run a 6.29 driven to the track.
 
Lookin for magnum headed la 360 0 decked kb107s with the mopar 508 .I can handle a 50/50 mix of trick and 91.whats with the kb pistons made for the magnum head la.I would rather have a ferfect quench.plus the kb107 r cheaper priced.
 
You need to establish, what you want it to do,dude. If you have a short block & no budget,tell us. If you have a nothing ,tell us. We don't know ,what you have...
Favorite low buck 12'ves Famoso combo : 4:10's ,727 trans,2800 stall converter.Stock .030" over block,re honed dingle ball. 9to 1 Speed Pro hyper pistons,Arp bolts,rods resized. 1:88/1:60 valves,pocket porting ,GOOD valve job.(where the money counts)....Crower "Ultra Street Beast" ,(269/282 advertised,223/235@.050,112 lobe centers.The headwork & attention to detail matter most here. Air Gap intake nice,a Rpm/LD 340 intake just as good. All steel 72 Dart,with a RPM idiot as a driver....
 
Might go 430 gears unsure yet maybe 456 im leaving 28 tires and slicks.or find some 29/9 slicks
 
It appears it will end up fastest with 456 I looked in summit they have 29 &30 slicks @9" wide.
 
Well the 360 I was gonna get the decided he didnt want 440.now im stuck with a 440 and 2 318s.what to do now.damn scrath the 508 of the board.I dont wanna run a 440 tomuch headache.
 
Wow...I have a small headache from reading all of that...LOL! Two things have to be rock solid: 1) Goals. What do you want the car to do? Daily driver capable, race only, street/strip?? 2) BUDGET. There are some pretty cheap ways to go fast without breaking the bank. Using what you have already helps.

My $.02...

440? You can bottle brush hone a 440, reuse the OE cast pistons, slide in a MP swap meet cam (.484 grind works GOOD), fresh CORRECT valve job, fresh springs for the cam, swap meet Holley Street Dom Manifold, swap meet (plan to rebuild it) Holley 750.

Rebuild stock 727, or one that you know works, OE 11" converter, add 3.91's, make it hook and you're deep in the 11's.

Been there, done the cheap 440 Abody thing a few times. Can't beat it for bang for the buck.



Now, if you're stuck on a small block, trade that 440 for a good 360 core. Same basic rebuild, with the KB 107's at zero deck. Or even cheaper is the Sealed Power HP405 slug, since you're going to have to deck the block either way) that MP .508 stick, advanced 4 degrees, EQ magnum heads (1.92's will work fine), Comp 26995 Beehive springs, Eddy Air Gap intake, same swap meet 750 DP as mentioned above. Get the quench right, .035-.040 max.

Add a 904 behind it and if you're REALLY bucks down, a reman 904 slant 6 converter. Same 3.91's and make it hook and you are also in the 11's.

Of course, basics have to be covered such as a recurved parts store distributor, a good ignition (MSD Street Fire is cheap and works great at these power levels) and either combo might take some tuning to get there, but I assure you...this ain't rocker science!
 
Man my brain is bleeding! Well three years later what did you come up with.

Jeff
 
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