Magnum Cam Selection Suggestions

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Walker434

Walker434

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Hello,

I am building a 360 magnum for my 71 dart swinger and trying to get my cam picked out so I can order some EQ Iron Rams with the correct Springs and retainers.

The goal: High 11s or low 12s but still street friendly. I have been talking back and forth with LXguy about his build but I wanted to hear what other folks had to say as well.

The Car: 3410 lbs with gas and me in it (Full street trim and sheet metal)904 with an 8 3/4 3.91 sure grip with SS springs, drag shocks, frame connectors and 275/60/15 MT ET drag radials. (Already got the traction sorted out)

The Engine: Starting with a junkyard 360 magnum 80,000 mile short block. I will be using headers, an Air gap and Holley 750 DP with Iron rams and whatever cam I end up with. MSD distributor and MSD 6AL box.

I will have a stall converter custom made for my combo once I get farther along but I assume it will be around 2800-3200 stall?

Also, vacuum isn't a huge issue becuase it is a non PB, non PS, non AC car and will be using mechanical secondaries.

Any help will be much appreciated. I am thinking around 230 duration at 0.050 on a 110 LSA but not sure about lift.

Any Suggestions?
 

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Could check out Hughes,Imm here,(Brian),Or Racer Brown has a nice grind. You're dead on the money,spec wise. Just assembled my own Iron Rams myself. With the Hughes 1110 springs and matching retainers. I considered. 530 lift safe. I measured .580 between bottom of retainer and top of valve guide seal. I used a HOWARD'S" retro-fit" LA hyd roller. 229/233@ .050,110 with a 106 intake center line. Forgot it was on a 1.5 ratio. Switched to a Chevy rocker setup. .520/.515 lift on a 1.5 rocker ratio.(oops!).Heads will peak at close to .525 lift anyway.
 
Sounds about right.

Just a note on the converter, your estimation is a little low imo. If you contact a few good converter companies don't be surprised to get a recommendation for a 9.5" converter in the 3500-4000 range. Don't be afraid of that, it's a good thing, and will be one of the biggest factors in you meeting your goal ( which btw I think you will ).
 
Okay thanks for the input. UOP if I get a converter custom made and spend some coin will 3500 stall still be street friendly? I've never driven anything on the street with that high of stall converter. What are thoughts on a Trans brake? I know LXguy was running one. Cost?
 
With a good converter, you can still drive the street just fine. For what its worth, my 410 stroker has an 8" PTC converter that flashes a little over 5000 RPM and it behaves it self quite well on the street. If you were driving right next to me you would have no idea that I had that much converter in it....unless I smack the loud peddle :D
 
Smaller diameter converters tend to be more efficient at part throttle, so it'll drive just like normal on the highway. My 3400 stall is a lock-up, but I only use it on the highway. Even then the rpm's only drop a little because the converter fits my car nicely. Never underestimate the benefits of a good converter.
 
I ended up putting my roller cam and EQ heads on an LA block. I ended up with 224/230 on 110 LSA (Wanted 108 LSA). I wanted a street friendly grind and even with the small chamber EQ heads and thin head gasket I only netted 8.7:1 compression ratio. If you can get closer to 9.5:1 compression ratio I would be looking at 230/234 on 108 LSA.

I hope to get to the track soon to get some real numbers. I am running the M1 dual plane intake with a Holley 750 vac sec, long tube headers with 2.5" exhaust to the bumper. I am running a Edge Racing 9.5" converter with a 3400 stall speed. It drives real nice on the street. I am also running a 904 and a 8 3/4 with 3.91 gears.
 
I was of the impression with the EQ Iron Rams (58CC) and the thin head gasket you would be in the 9.5:1 range? I thought they were 9:1 from the factory? I guess I need to figure this out becuase that could make a difference on my cam selection.
 
La pistons .080-.100 in the hole. Magnums about .050-060". Plus the Magnum pistons have less dish. You should be 9.3-9.5 compression wise.
 
I have been talking with Comp Cams about this and they are recommending a cam with .513 lift. The guy says you can't go higher than .520 on the stock magnum bottom end without piston to valve clearence issues. Anyone else run into this? I thought LXguy was running .544 lift on a stock magnum bottom end?

Any help is appreciated.
 
Walker434 said:
I have been talking with Comp Cams about this and they are recommending a cam with .513 lift. The guy says you can't go higher than .520 on the stock magnum bottom end without piston to valve clearence issues. Anyone else run into this? I thought LXguy was running .544 lift on a stock magnum bottom end?

Any help is appreciated.
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I am not saying run his cam but the whiplash cam from hughes for the 360 is .544 and its for stock engines so the comp guy is full of **** but then again I do suppose it depends on duration too for how much lift u can run.
 
What year magnum engine are you running?

My son and I are building a 91 360 engine which is the last year before magnum. I ordered a cam from Hughes and told them I wanted the cam with the extended nose for the mechanical fuel pump. They sent me the cam for the electric fuel pump and a "band-aid nose extention kit" at an additional $30 with the cam. Instead of waiting until they got the proper cam in and sending that to me at the same price minus the $30 for the shoddy nose extender kit. I did not like the way is was designed, so I did some of my own modifications to make it work better. I would have preferred that they sent me the proper cam, even if it meant I had to wait.

Don't let them do the same to you.
 
It is a 2001 out of a 1500 ram. I too would like to run a mechanical fuel pump so I will be asking for the longer snout cam. I'd rather not run the extender.
 
walker434 said:
it is a 2001 out of a 1500 ram. I too would like to run a mechanical fuel pump so i will be asking for the longer snout cam. I'd rather not run the extender.
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do not let them give you the extender. It has been nothing but headaches for me. It is underdesigned!!! If they send you the cam without the nose and include the 'extender' package send it back!!!

It's a bs way of charging an extra $30 instead of sending the correct cam. You tell them i said so and i was not impressed with the way the nose extender was engineered. I had to redo it myslef. Lucliky i have a mechanical engineering degree.
 
Walker434 said:
I have been talking with Comp Cams about this and they are recommending a cam with .513 lift. The guy says you can't go higher than .520 on the stock magnum bottom end without piston to valve clearence issues. Anyone else run into this? I thought LXguy was running .544 lift on a stock magnum bottom end?

Any help is appreciated.
Click to expand...
Pretty freakin funny,gross valve lift has nothing to do with VP clearance. Your best choice would be to call Tim @ Bullet cams. I'm guessing the Comp guy was talking guide to retainer clearance, who knows,just do not rely on a Comp phone answer guy to give good advice,he's only looking at some limited notes.LOL
 
What is it with advice from Comp lately? This is one of may threads where they have given people flat out wrong info. Bad thing is, like on another thread, the guy's gonna listen to um. Oh well.
 
RustyRatRod said:
What is it with advice from Comp lately? This is one of may threads where they have given people flat out wrong info. Bad thing is, like on another thread, the guy's gonna listen to um. Oh well.
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Comp's been good at that for years,there are some good guys but you better know how to reach them and they don't answer the consumer phone. Been that way for years.
 
Ok guys just an update. I ended up going with a comp custom grind. They ground it on a long snout so I can use a mechanical fuel pump. Below are the specs. I'm really hoping this thing will scream. It's very close to the cam they put in the 380 HP 360 crate engines which made closer to 400 HP with the right intake and carb. Thoughts and opinions are welcome but I've already made up my mind becuase it got here in the mail today :blob:

Lift: .506 .513

Duration @ .050: 230 236

LSA: 110

Intake C/L: 106
 
krazykuda said:
do not let them give you the extender. It has been nothing but headaches for me. It is underdesigned!!! If they send you the cam without the nose and include the 'extender' package send it back!!!

It's a bs way of charging an extra $30 instead of sending the correct cam. You tell them i said so and i was not impressed with the way the nose extender was engineered. I had to redo it myslef. Lucliky i have a mechanical engineering degree.
Click to expand...

If that's not enough, that damned cam extender I bought from them had to be machined down to properly fit-that ran another $30. I got a little too pissed about that one in my 5.2 Magnum install thread-over it now, and looking back I was being irrational, but not before I had some less than stellar things to a fella named Dave on the phone at Hughes. I was just upset that they sell a parts kit that needs to be machined just to use when that's its only function...effectively doubled the price.

What is it with advice from Comp lately? This is one of may threads where they have given people flat out wrong info.
Click to expand...

Truth-this crap has been going on for years. My friend and I called COMP four times in one day to get advice about a good grind for his blown '95 Cobra with a 331-none of them gave even remotely similar recommendations. I like their products, but there's no way in hell I would actually solicit advice from any of their techs after than incident. I'm sure there's plenty of good ones, but it seemed at the time as though their customer mentality was more like fast food-toss out a rec, take the order, move on to the next customer almost without regard to the level of accuracy.

...maybe we just talked to the wrong folks.

Sorry...rant over
 
Not at all.Phone techs ,can drive you batty. For cams,George Strigel(Clay Smith), he answers the phone,AND grinds the cams. Oliver Reed at Crower,TOP NOTCH. Engle Cams,has a good guy at the phone,just can't remember his name.
 
How much did the cam cost you??? And what is the part # or how to order this grind...

I would like to try this cam....

Thanks.....................................PETE...................
 
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