Mismatched Cam and Heads?

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ColeTrickle74

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I've been reading around a lot and it looks like alot of people are using a .509 cam with Eddy heads on a 360. I picked up a cam with 519/524 lift and 250/256 @50. Would I suffer any huge performance loss when using stock port eddy heads? I couldn't really find an RPM range for the heads, cam is advertised at 3,000-7,000. Going with a 3k convertor and 4.10 gears as well.
 
you'll be fine. I would try to get your compression up to 10.5 - 11 though. should still run good on pump gas.
 
Thats what I'm hoping for. I already have a set of kb107's and I'll be using the scat rods so I think I should be close to 10.5.
 
Heads don't really have an RPM range, they have port volume and port flow at certain pressure drops along with valve sizes. BTW do you really need that much duration? I suppose if it's a more strip-oriented car though...
 
That cam is fairly large. The .509 is a race cam in most small blocks with stock stroke, and is not used by guys that really know what they are doing. I would replace it with something smaller by about 10° less at .050. The heads are fine, they will work very well on a 360 in stock form. But, make sure you replace the springs with thte ones the camshaft manufacturer recommends. The Edelbrock ones are not very strong, certainly not enough for most modern grinds.
 
I've been running the Edelbrock heads on both my 416 and 366,with the springs they come with,i have been using cams with .513/.533 and .533/.552 lift for 3 seasons will no spring problems..
 
So long as they pass muster (like the pressures). I know for anything beyond 230°@.050 in a modern fast rate, they are not strong enough by themselves. That's a Comp XE274H, the Lunatis beyond their 268, etc. Those all take true dual springs. If they have worked for you, that's great. I've used one set of OEM Edelbrocks. All the others got better ones.
 
lol well its kind of too late to decide if I need that much duration. Everything is about to get put together within the month. Considering I already have the cam and heads, what would you suggest to remedy this situation a little bit, or should I just shut up, bolt on and go? Everythings still in boxes so if I need to buy a new cam so be it.
 
The heads will work fine with that cam but a 3000 converter is pretty tight for a 360 with a cam that big. You probably need a converter closer to 4000~4200 or go with a smaller cam. JMHO
 
Thats ok, the converter I don't have yet. So move the converter up 1k. Anyone else have an opinion on this cam/head combo?
 
What is the honest intended use for this car. If it is mainly going to see street duty with an occasional jaunt at the strip, I agree with Moper re: a slightly less aggressive cam change.
 
Yes mostly street driven, a few days a week. How bad would the drivability on the street be? I'm not too too concerned with it being rough, I'm already used to having no vacuum. What else would I have to worry about? Would a 4k convertor be too loose for a street machine?
 
Well, the cam has a RPM range, that is where driveabilty really starts. Seeing that you have a 4.10 gear, you can kind of get an idea how long the car will take to get to that RPM where the cam kicks in. You'll feel it (The cam) come in, turn on sort off.

Looking at the combo, I myself would opt for a smaller cam by 10*'s.

OR

Make a jump in gear ratio to get out of the hole at a reasonable rate. The cam is large enuff that the 4.10's are actually holding you back.

Also, the Edelbrock heads, in a OOTB condition are very good for a street strip 360 in it's port size and advertised flow rate. The cam controls the RPM in which the engine and therefore, the car operate in.
The head and cam can be slightly unbalanced and still give a good performance, however, in this case, theres a bit much cam for the set up at hand.

Along with the gear ratio is converter, carb, compresion and cars weight.

The MP .509 cam is good for a A body to be propelled into the 12's easy, low 12's with a good set up. I have met 3 or 4 guys running hi 11's in a lighten race Duster. And I mean a race car only. No wipers, heat/defrost, 1 seat, roll cage etc..... you know the drill.
 
The heads can have a port to small, or not flow enuff for a given engine size and made worse with a big cam. To small a port and the engine will not make power up top.

To large a port, no power down low and power only up top and often, to high in the RPM range.
The RPM head is good for a street strip 340/360 and up to approx. 372 cubes. Of course, this is build dependent. You could use the Edel. heads on a 400+ cube engine. But I would not expect it to spin and make noteable and worthwhile power past 6000 rpm. Porting the head is the answer or a move to a different head.


I might have created a bit more fog in this answer, but I hope it did get a little brighter out.
 
Okay that was a good answer :)
I figured I would be taking a little performance hit with a bigger cam. I was shooting for 12's this year, think its still reasonable with this cam and stock eddys? I doubt I'll have the funds to get my heads done this year. I already have the cam and lifters, so it looks like I'll find out what happens. I might be able to get another cam but I kinda spent most of my money on those shiny heads.

Looks like I'll be switching to a 3500-4000 converter, so that should help out a little.
 
Personaly I would loose both those hyd cams Go with a solid "less duration @ same lifts" and run the comp up to 11.5 with .030 Quench otherwise using the eddys over a set of irons knida pointless since the eddys dont flow much better than good irons and the thermal loss from the aluminum is costly~
 
Loose the cam...get something smaller. You'll be happy you did. Check out Hughes for a good selection. Hydraulic or Solid either one. Get some 3.55's or 3.91's and shoot for 1500-6000 range. You'll love the low end torque on the street and you'll have the potential to hit 12's at the strip forsure.
 
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