This cam ok for low comp street motor?

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dmopar74

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It’ll work fine.

Id recommend a valve spring upgrade to go with it.

And if the heads have rotators on the exhaust valves, you’ll want to replace those with regular retainers.
 
I just used that cam in my 8.5:1 400 build. It works well. Since the specs were very similar to the factory magnum cam, I just used stock replacement HP valve springs, but then again I don't rev it past 5000 rpm.
 
Yup. That's a decent one. It's a really old grind that's been around a long time. Very popular because it works.
 
I had a Cuda with an 8.5 comp 440. It had a small single plane and headers, stock roadrunner converter, 3.23s and a mp 284 cam. Car ran like a bat out of hell. Bottom end was great. 2000 to 5500 was really strong. For a daily driver the cam you have will work fine. I wouldn’t be afraid to use a comp 268 xe if you want some rumble and a little more power.
 
Tthanks all. I'm still trying to learn about cams, guess I need to learn about valve springs as well. Anybody know what lift stock 452 head springs are good for?
 
Most older Mopar heads and stock rocker arms will accommodate right around 500 lift. But springs need to be rated to that lift also, meaning just because the spring doesn't bind and The rocker can handle it doesn't mean the springs pressure will be adequate for the lift. Spring are no place to skimp.
 
aaronk785 said:
I had a Cuda with an 8.5 comp 440. It had a small single plane and headers, stock roadrunner converter, 3.23s and a mp 284 cam. Car ran like a bat out of hell. Bottom end was great. 2000 to 5500 was really strong. For a daily driver the cam you have will work fine. I wouldn’t be afraid to use a comp 268 xe if you want some rumble and a little more power.
Click to expand...
I would use a Comp if I was building something for one of my enemies.
 
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dmopar74 said:
Tthanks all. I'm still trying to learn about cams, guess I need to learn about valve springs as well. Anybody know what lift stock 452 head springs are good for?
Click to expand...
They won't support the cam you are talking about. It's not all about max lift. It's also about spring RATE. You need toe right springs for any cam. Even if you replaced a stock cam for a stock cam, because the old springs are worn, they need replacing, regardless.
 
dmopar74 said:
Tthanks all. I'm still trying to learn about cams, guess I need to learn about valve springs as well. Anybody know what lift stock 452 head springs are good for?
Click to expand...
You also have to watch spring retainer to guide clearance. Sometimes you need to trim the guides down to avoid contact there with higher than stock lift cams.
 
I am running that cam with the VS430 springs in my D100 - in an otherwise stock motorhome 440. Stock cast iron intake manifold. Fitech fuel injection. HEI distributor. Stock truck exhaust manifolds with 2.5 inch true dual exhaust. The pistons are WAY down in the hole. I'm guessing less than 8:1 compression. It works great in the truck for cruising around. I never rev it past 5000 RPM but it probably has a little more in it. Slightly noticeable idle. Stock converter with 3.21 open rear end. Plenty of low end torque - even in that heavy truck with relatively high gears and 29 inch tall tires. I'm overall very happy with the combo.
 
dmopar74 said:
Does anybody think this is too much cam for such a low compression motor? I'm kinda trying to keep with the summit cams cause they're so cheap and to swap from the /6 to the 440 I basically have to buy a whole new drivetrain from radiator to rear end.
Summit Racing SUM-K6421 Summit Racing™ Muscle Car Replacement Cam and Lifter Kits | Summit Racing
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People that know more than I do don't think your first cam is too much for a low compression 440. And for whatever it's worth, I would go with the first cam over the second.

PS: you can always mill the heads .060 to get the CR up.
 
Eventually I will put some aluminum heads on. For now I plan on the .020 steel head gaskets and will check to see how much to mill the heads. How far can you mill the heads without having to mill the intake as well?
 
dmopar74 said:
Eventually I will put some aluminum heads on. For now I plan on the .020 steel head gaskets and will check to see how much to mill the heads. How far can you mill the heads without having to mill the intake as well?
Click to expand...

I've milled heads .030 without milling anything else. Any more than that, I would mill the intake side of the head rather than the intake manifold.
 
Is it too big? It depends on what you're trying to do . It will give you a little more mid-range power but yes it's probably not be ideal for air conditioning and power brakes but it will work. And yes a little more compression would definitely help all around. Also you'll probably want to advance it at least four degrees.
 
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If you’re pulling the heads pull the valves and open up the shrouding in the bowls… It’s good for ten to twenty hp.
 
That is their version of a factory HP cam. You will note the duration at .050 is actually less than the 6400 cam. 208/210 versus 214/224. That is why I chose the 6400.
 
The K6421 is basically a repop of the old factory non-hp 4bbl cam*, and is a step down(in terms of power potential) from the one in the first post.

*325-330hp 383 vs the 335hp 383
350hp 440 vs the 375hp 440
 
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Sounds like the 6400 cam is the way to go.
Any experience with the summit carbs? Street demon? Again the summit carbs are cheap, I believe a 750 is sufficient.
 
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