416" small block cam

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ncDemon

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I'm not generally one to solicit advice on such a polarizing subject, but I really can't convince myself that I know enough to make a good decision here.
Here's the goods-
416" sb- forged rotating assembly
Heads- waiting on the Predator sb heads to come in from Marsh performance (basically sounds like an edelbrock copy, but with the benefit of coming from a machine shop- so quality should be better.) I've heard good things about the big block version. + half the price of the eddy's. Going to port and polish the heads, gasket match intake.
I understand the heads are going to be the limiting factor in feeding the increased volume- which leads me wonder about the cam. My question -Is it worthwhile to go to a solid (or even hydraulic) roller with this type head? I feel like it would be a no brainer on w2 heads.
Gut says just to go with a big hydraulic flat tappet and don't worry about. Brain says we are only doing this once, do it right.
Car is 72 demon, 4 speed, 355 gears, currently on stock 14" rally wheels (wheel tire and suspension will be the next round of upgrades) going more pro touring type, I'm all done with drag racing ( aside from the occasional stop light thing...
All input is welcome
Thanks!
 
What are your constraints?:

Idle quality/loudness?

Street friendly-ness and ability to idle at length in warm weather (traffic)?

I went solid flat tappet to get a little more rpm and reliability at rpm out of it on the top end. But I think that's more of a personal thing. Some just don't like the tappet sound.
 
Probably best to talk to your engine builder or cam company's. Pro touring I would think would be mild like right around 240 @.050 and 530 to 550 lift if not reving more than 6,400 or so.
 
I originally had a hydraulic flat tappet in my 360, but now I am going with a pretty mild ish solid roller cam. Really depends on how deep your pockets are but I definitely think it was worth it to convert to a roller cam. My cam is 242 @.050 and .570 lift. Solids are a bit noisy but I like the sound, some dont.

I had this debate on here about either hydro of solid roller and came to the conclusion to go solid based on others advice.
 
I have a Comp Cams 268XE in my 69 340 4 speed Cuda. With an Air Gap, headers a 750 CFM carb, and 3.55 gears it really screams. Should be right at 370 HP since I followed a recipe in an old Mopar Muscle magazine. The 268XE runs great with a nice, lopey idle. For your 408, I would seriously consider their 272XE. With headers, Air Gap and 750 CFM carb, 425-430 HP should be easy.
 
EL5DEMON340 said:
Probably best to talk to your engine builder or cam company's. Pro touring I would think would be mild like right around 240 @.050 and 530 to 550 lift if not reving more than 6,400 or so.
Click to expand...

That's about what I have in my 416 stroker, E-brock heads, 9.8:1. I run a Comp XE274-S. With a handling suspension on the more serious side, it doesn't hook up on the street. I would trade off low rpm HPTQ for HP/TQ over 3000 rpm.

I'm running a M1 single plane and a BG Silver Claw "750" DP in an attempt for more upper rpm power. Carb could be too big. I believe BG rated those differently than common Holley 750's :dontknow: I still think it starts going flat after 5800-6000 rpm.
 
Got a Voodoo 30200741 solid flat tappit in my 9.8:1 aluminum headed 416 .546/.566 243/251 with howards direct lube lifters. Engine made over 525 HP w 540 TQ on the dyno. Mike @ MRL did my heads.
 
Have used the Lunati "voodoo" 10200705 .533/.552 hyd. cam in 2 different engines with great results 416 and a 360:D:D
 
autoxcuda said:
What are your constraints?:

Idle quality/loudness?

Street friendly-ness and ability to idle at length in warm weather (traffic)?
Click to expand...

This. I too had the thought going through my head about doing it right the first time and not wanting to regret not building the engine way I wanted. So I dug deeper in my pockets for MRL solid rollers and a Comp custom cam setup. It's all about what YOU want the engine to do.
 
The problem with going milder on the cam, which more suits what you describe - is that you have to have the dished pistons to get it to live well on any pump swill you want to run. The 4" stroke gives a lot of compression by itself - so you have to build the lower end with regard to the top end and cam choices. Not the other way around.
What pistons do you have with the kit?
 

I guess I should have included this from the start. 20 cc dish forged pistons. should be right around 10:1 with the predator heads.
Noise really isn't a concern. I don't think lifter noise is going to drown out the exhaust note. If it does I'll get some of those fancy electric cutouts :) .
Too much power to hook up? That would be a nice problem...I'll just keep going down(numerically) gear wise till it suits me.(I'm also looking at a 6 speed swap down the road)
My thought with the roller cam was geared more toward being able to get the valve open quicker- I like the idea of this combo operating as efficiently as possible with the block,heads and rotating assembly selected. Aside from waiting on the heads and an above freezing day to clean the block off (post machine shop) I'm ready to start putting this thing together.
I'm saving enough the heads to make up some of the cost on the more expensive valvetrain so that's less of an issue, within reason. The lunati email-
"The cam I recommend is part number 40200731. This cam is 237/243 at .050,
.566/.578 on the lift, and it is cut on a 110 LSA with a 106 intake
centerline."
Discussions with other cam companies (I wont call names) were all over the map depending on who I talked to, leading to a low degree of confidence in their recommendations.
Id like to go to Todd (Marsh) with a couple different ideas when he finally gets my heads in.
Any thoughts on rockers if I go the solid roller route?
Thanks a bunch for all the great feedback here. I really do appreciate it.
 
The static ratio is too high for that cam. At least IMO. I'd like to see 1/2 pt of static lost if you want a cam under 245 @ .050. Or have them open up the LSA by 2-4 degrees. Especially with the 6sp where the rpms will be down, you'll want to watch the dynamic compression, and the only way to do that is with lowering the static if you want a smller cam. You'll need adjustable rockers regardless of the cam choice. The hydraulics need preload adjustment, solids need lash. I think hydraulic rollers are a waste of money, and solid rollers need the block bushed. So those in terms of my opinion are out. Go with a solid flat tappet, follow the breaking assembly and procedure, run the right oil, and you'll be fine and you can pocket the cash the roller stuff needs.
 
I've had a stroker since 2003. Hydraulic roller all the way. Smooth, no broken parts, no break in, no oil nonsense. More money, but worth it.
 
Gmachine- did you go with one of the drop in lifters? I've already got my block back from the machine shop and I hate to take it back...5 hour round trip..
 
Moper- pardon my ignorance, but what is the advantage of a solid flat tappet over hydraulic flat tappet?
 
The solid should rev much higher, hydraulic lifters tend to pump up and start to "float" valves over 5,500 or so
 
I was thinking that using the edlbrock type heads would limit rpm to 6k or so on a stroker anyway.
There is just way to much to sort out with cam selection! It's no wonder so many people just use a cookie cutter recipe...
 
I use the comp drop in lifter. I had a solid roller initally and took it after the first couple years. I ran a scott brown design 230/243 for about 8 years. I just freshened thr motor and had Brian Hafligler spec me a new cam that has a little more intake duration and a 112 lobe center. 11.5 comp with ported eddy and 2.08 intakes. Runs real strong.
 
ncDemon said:
I was thinking that using the edlbrock type heads would limit rpm to 6k or so on a stroker anyway.
There is just way to much to sort out with cam selection! It's no wonder so many people just use a cookie cutter recipe...
Click to expand...

That's why if you go roller, get a custom grind for your setup. It's no more expensive than a cookie cutter roller cam. Tell the mfr what you want and they will tailor a cam to that. A lot of roller lifters are drop in nowadays so don't let people tell you that you need to bush the lifter bores because you don't. And don't concentrate much on what the static CR is. Just get your dynamic around 8.5 or less and you'll be fine on pump gas.
 
ncDemon said:
I guess I should have included this from the start. 20 cc dish forged pistons. should be right around 10:1 with the predator heads.
Noise really isn't a concern. I don't think lifter noise is going to drown out the exhaust note. If it does I'll get some of those fancy electric cutouts :) .
Too much power to hook up? That would be a nice problem...I'll just keep going down(numerically) gear wise till it suits me.(I'm also looking at a 6 speed swap down the road)
My thought with the roller cam was geared more toward being able to get the valve open quicker- I like the idea of this combo operating as efficiently as possible with the block,heads and rotating assembly selected. Aside from waiting on the heads and an above freezing day to clean the block off (post machine shop) I'm ready to start putting this thing together.
I'm saving enough the heads to make up some of the cost on the more expensive valvetrain so that's less of an issue, within reason. The lunati email-
"The cam I recommend is part number 40200731. This cam is 237/243 at .050,
.566/.578 on the lift, and it is cut on a 110 LSA with a 106 intake
centerline."
Discussions with other cam companies (I wont call names) were all over the map depending on who I talked to, leading to a low degree of confidence in their recommendations.
Id like to go to Todd (Marsh) with a couple different ideas when he finally gets my heads in.
Any thoughts on rockers if I go the solid roller route?
Thanks a bunch for all the great feedback here. I really do appreciate it.
Click to expand...

I run 20cc dished Icon piston in a 4.070" (340 0.030 over). I cc'd my Small Chamber Edelbrock heads at 65cc. Even though they are advertised at 63cc.

That netted me 9.7-9.8 to 1 compression with quench between .015 and .030". I smoothed the edge in the combustion chamber and matched the chamber edges to the actual bore too. Maybe that helps a little

I'm on the edge with pinging 91 octane California pump gas with a 236/242 @ 0.050 cam. Probably would be better at 9.5:1. Just as Moper suggest BTW.

Wonder what a 65cc Edelbrock head (actually measures 67cc) drop the compression too?

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I see no problem with the "cookie cutter" cams, as long as you pick the right one for your combo. Case and point, my 410 stroker. It has a small solid roller (Comp XR286R), Edelbrock heads, pump gas compression, weighs around 3200-3250 lbs, and runs mid 10's....its all about the combo and the tuning.
 
moper said:
The static ratio is too high for that cam. At least IMO. I'd like to see 1/2 pt of static lost if you want a cam under 245 @ .050. Or have them open up the LSA by 2-4 degrees.

You'll need adjustable rockers regardless of the cam choice. The hydraulics need preload adjustment, solids need lash. I think hydraulic rollers are a waste of money. Go with a solid flat tappet.
Click to expand...

I'm with this guy.

This cam is along the lines of what he is talking about.

Crower: CRO-31321
 
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