Looking to cam up

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MopaR&D

MopaR&D

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I have a Voodoo 256/262 cam in my 360 that I swapped over from my old 318 but I think my engine could really use a bigger cam. It's .060"-over, KB flat tops (10.4:1 comp), untouched Magnum heads, Air-Gap intake, Hedman shorty headers 1 5/8" and 750 Mighty Demon (when I'm racing, 625 cfm AFB for the street). 904 trans with mild shift kit and stock converter; I have an 8 3/4" rear and plan on swapping between 4.10 gears for the strip and 3.23 gears for the street so it needs to have decent low-end.

The main issue I'm running into is max lift at the valves, the heads are stock Magnums with the Hughes retainers and 'straight' springs #1110, I believe this is good up to .525" lift (am I right??) which is very easy to go over with the factory 1.6:1 rockers. One I'm liking so far is the Bracket Master 292 .480" but people have mentioned it's pretty old-school. I would go with the 268/276 Voodoo in a heartbeat but I'm afraid the exhaust lift will be too much. I'm open to other brands too but they seem to share pretty similar grinds when it comes to the conventional slower-ramped profiles.
 
I'm not sure what the maximum lift your Mag heads can handle.....Obviously bigger and some more duration would be better with the 4.10's, but I have to think if your looking for some "et", the best money spent at this point would be on a good/custom torque converter...
 
You should be careful. Unless your engine spark knocks even on super, no way is your compression 10.4 with iron heads and that little bitty cam. If you "cam up" as you call it, you will likely lose some bottom end torque. If you run a compression test first, that should give you an idea. If you really have 10.4 with that small cam, your cylinder pressure should be pretty high. I would suspect in the 180 PSI range.
 
You would be right Rusty but a couple things come into play... one I reside around 6000' above sea level, two my engine is a proper "quench" build with zero-deck pistons and .040" head gasket thickness I cc'd the heads myself and actual static compression was 10.42:1. I actually run mid-grade (87 octane up here) on the street and there's no pinging unless I really try to; timing is 10* idle with around 32* all in by 2200 and I think it could use a tad more for max power.

Good point OldmanRick I will definitely consider a converter but I do have ultimate plans to convert my car to a 4/5-speed stick depends on how much money I start making over the next couple years lol... I do have a "mystery" torque converter (~2600 stall) I recently swapped out for a stock unit because the slippage got on my nerves.
 
RustyRatRod said:
You should be careful. Unless your engine spark knocks even on super, no way is your compression 10.4 with iron heads and that little bitty cam. If you "cam up" as you call it, you will likely lose some bottom end torque. If you run a compression test first, that should give you an idea. If you really have 10.4 with that small cam, your cylinder pressure should be pretty high. I would suspect in the 180 PSI range.
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This is a good idea.

I'm supposed to have 10.5:1. Car makes 160 psi cranking compression with [email protected] and 112cl
 
I'm telling you guys my compression is for real I purposely built this engine for max cylinder pressure at high altitude... I can do a quick compression test to prove it but it would be easier if you just believe me I cc'd all 8 chambers myself and measured the quench distance with clay when I put the engine together :evil3:
 
I have 185 cylinder pressure 10.5 mahle pistons block zero decked 65 cc heads and no way can I run anything under 94 octane , still pings once in a while with the iron heads , changing to alu heads , hope to get rid of pinging .
If you are running 87 octane please tell me how , cause there is no way in hell I can , we have played with timing , carbs everything and no way it can run 87 octane .
What times are you running in the 1/4 mile ? If you tell me under 13.00 I'll be at your door next week for complete overhaul .
 
GUYS pay attention lol I am at 6000' elevation if I was at sea level it would be a whole different ball game. Jerry6 what's your quench like?
 
roccodart440 said:
This is a good idea.

I'm supposed to have 10.5:1. Car makes 160 psi cranking compression with [email protected] and 112cl
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roccodart440 what kind of cam and rocker ratio are you running and what lift does it make at the valves? Also what's your gearing and converter stall like? Not to mention what's your elevation where you live if you happen to know? 242* @.050" is on the upper end of durations I'm considering because like I said the thin air up here in the mountains lowers the dynamic compression ratio a significant amount; a cam that would work well with 10.5:1 static compression around sea level might lose enough low-end torque to be sluggish at high altitude.

Just to give you an idea my current engine/drivetrain combo should be good for mid-high 13's at sea level. BUT up here at Bandimere Speedway my best run so far has been a 14.9 @ 96.4 MPH. Cars running 13's at this altitude are built up much more than mine thus would be running in the 11-12 second range at sea level.

It's a real bummer when you're racing guys with blowers/turbos the difference to N/A is drastic with the thin air. For sure my next major engine project will be to rebuild my old 318 into a turbo engine and make an easy 500 HP.
 
Looking at the Isky "280-MEGA" .485" lift, 232* @ .050" anyone used this before? Saw RRR mentioned them in the other current cam thread ha

BTW just checked jerry6 Montreal is basically at sea level lol you're making a solid 25% more power and torque than in my location... no surprise you have pinging with that compression and run so much faster than me :wack: Still running those Tight Tubes btw your thread on them saved my butt when I was in a bind putting my car back together.
 
MOPEkidD-3 said:
roccodart440 what kind of cam and rocker ratio are you running and what lift does it make at the valves?

It's a mopar purple shaft.

1:5 rockers

lift at valves? Don't know. advertised is .528 with a 1:5 ratio rocker. .557 with 1:6.

Also what's your gearing and converter stall like?

Used to have 3:73 with 26" tire. Now have 4:56 with 28". Will be going to 29" when these are done.

3500 convertor.

Not to mention what's your elevation where you live

anywhere from 600-2000ft.

.
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Hope that helps
 
Yes on .525" lift with the 1110 springs,and stock valve guide height. The valve guide height limits you,can be turned down,heads off the engine.
 
Abodybomber said:
Yes on .525" lift with the 1110 springs,and stock valve guide height. The valve guide height limits you,can be turned down,heads off the engine.
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"Word" as the kids say... Any more lift than that anyway would need porting to flow at all these stock Magnums level off around .500" IIRC

Next stage will be ported EQ's or E-brocks depends on how much money I wanna burn ha :twisted:
 
MOPEkidD-3 said:
"Word" as the kids say... Any more lift than that anyway would need porting to flow at all these stock Magnums level off around .500" IIRC

Next stage will be ported EQ's or E-brocks depends on how much money I wanna burn ha :twisted:
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You got it. E.Q's a 20+ c.f.m out of the box, to start . Adding a 58 c.c. chamber,doesn't help. How about contacting OU812?.
 
AJ/FormS said:
To Jerry6; I run 87 with [email protected] @900ft and the edelbrock65cc heads, and .035 quench. 14 years/125000miles.Still strong.Goes 93mph in the 1/8th with 3.55s
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I hope to do as well , hope the edelbrock heads do the trick , running with 87 octane will save me 20-30 cents a litre , it adds up quickly . I would be real happy running 93 mph in the 1/8 th , hope to test next week if the weather cooperates .
 
Abodybomber said:
You got it. E.Q's a 20+ c.f.m out of the box, to start . Adding a 58 c.c. chamber,doesn't help. How about contacting OU812?.
Click to expand...

That's why i'm kinda leaning towards the edelbrocks, I also want to convert "back" to shaft rockers and LA intake bolt pattern it'll make things much easier in the future
 
MOPEkidD-3 said:
That's why i'm kinda leaning towards the edelbrocks, I also want to convert "back" to shaft rockers and LA intake bolt pattern it'll make things much easier in the future
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For my money,good move for your combination everywhere. Did Eddy's & E.Q.'s, different situation's both. The Eddy's would be the better choice ,on that 360. Lap in the seats,& and check valve to valve guide clearance at a minimum, personal experience.
 
Abodybomber said:
For my money,good move for your combination everywhere. Did Eddy's & E.Q.'s, different situation's both. The Eddy's would be the better choice ,on that 360. Lap in the seats,& and check valve to valve guide clearance at a minimum, personal experience.
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For sure after all the quality control issues I've read about with those I'm gonna buy the heads bare, port them a bit myself, then have a shop do the valve job and check the guides. Honestly the only reason I put on Magnums in the first place was because of the closed chambers, unfortunately they are the only factory heads for 360s configured that way. LA-style heads with shaft rockers, LA manifold mounting AND closed chambers would be optimal for me. Needs to lose some weight off the front end as well my car has like a 56/44 weight distribution lol; definitely gonna relocate battery to the trunk, also thinking of ditching the power steering.
 
MOPEkidD-3 said:
For sure after all the quality control issues I've read about with those I'm gonna buy the heads bare, port them a bit myself, then have a shop do the valve job and check the guides. Honestly the only reason I put on Magnums in the first place was because of the closed chambers, unfortunately they are the only factory heads for 360s configured that way. LA-style heads with shaft rockers, LA manifold mounting AND closed chambers would be optimal for me. Needs to lose some weight off the front end as well my car has like a 56/44 weight distribution lol; definitely gonna relocate battery to the trunk, also thinking of ditching the power steering.
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The most logical moves.
 
Also I think I'm gonna use Rhoads lifters with that Isky 280 cam the more I look into them the better they seem... variable valve timing on a muscle car engine HELL yes. Should have noticeably more "area under the curve" with all that extra torque on the lower end from the reduced duration.
 
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