dyno numbers

[AJ/FormS]

I like that idea
Opening it up to 114LDA will pull back the ICA to 69*, and that,in at 112*, with an Scr of 10.5, will net a Dcr of 8.15/163psi; with no other mods. It does, however, reduce the overlap to 49*. In this application, I don't see that as a big deal.
But, if you're gonna go custom..... you might as well go whole hog custom.And that would require a call to your favorite Grinder.

 

[AJ/FormS]

The Voodoo 30200740 which specs out at 264/274/110 in at 106, and has lifts of .525/.546, with 050s of 235/243, is an incredibly fast cam. The Dcr with an Scr of 10.5 might be 8.84/181psi.
Have I got the right cam?
There is no doubt this puppy would be awesome with aluminum heads, but what's your thinking nm9?

I redid the numbers at 9.8Scr and they come in at 8.26/166psi. From 10.5 to 9.8 is more than gaskets for sure.But I love the speed of that cam. hmmmmmmmmmm

Hyup they have one bigger, that specs 272/280/110in at 108 the ICA is64* and that translates to 8.48/171psi, at 10.5Scr. That might work with hi-test, in this rig. For sure it will work in first, Second will be close. Third with the revs buried should be good.The overlap is back to 56* .. I like it.
Besides,retiming the cam to 110/112 or .060 headgaskets or a combination should drop the Dcr down to doable-eas, if needs be. With both; gaskets and; in at 112, I get Scr of 10.25,Dcr of 8.0/166psi.BTW the lifts are spec as .546/.566 with 1.5s, and we know the stock paddle-rockers ain't 1.5s. With 1.42s say, the lifts would squeak in at; .517/.536. I bet that's doable without yanking the heads.

Yeah I know it's more cam than he needs, but it will outperform that 2177 in every way possible. The Voodoo 272/110 pretty much steals all the extra numbers from the power stroke, and gives 'em to overlap/exhaust.Otherwise the advertised numbers are pretty much the same. Sweet! And the 050 numbers increase from 204/204 to 243/251, if you can believe that! That is a huge increase; about 7 cam sizes, for what is essentially the same advertised. FWIW this is a tight-lash design. I think I saw .016
I think I might get me one of those badboys.
Opinions welcome as always.

 

[nm9stheham]

Well, my thinking is that this Voodoo solid has the fast ramps and lots of lift to keep the torque band wide with limited duration to work with what is essentially a 3 speed manual. The next step up, the 272/280 will be decent but I would like to run as a narrow a duration as I could to keep the low end torque up. I would even limit ignition timing some to make it work. (Heresy LOL!) And the 272's lifts are pushing up there pretty good and the OP will have to pay more and more attention to valvetrain clearances; the exhaust side is getting well up there in lift even with the 264.

I am also questioning the actual SCR of the engine here. It is easy to say 10.5 based on a simple description of the parts installed in years past, but unless there are some compression numbers taken and posted, it will be somewhat of a guess. If it was actually 10:1 then the 262 solid would be better. And lowering the SCR/DCR 0.3 points is likely a matter of just 2-3 cc's in this case.

But I also keep forgetting that solid durations will be narrower than rated when lashed, so maybe the 272 one is the ticket. I have not looked much beyond these cams except at the standard Crane solid flat tappet units but I don't see the best choices there.

 

[Abodybomber]

thanks for the tips.

Here's the situation, I have a 408, its an older 408 done in the early 90s, its in my 78 powerwagon, it was done by my uncle and grandfather back then. I have it now, it has a little over 860 miles on the engine. I run it about once a month or so. It's in the body work resto stage now. it has a 4 speed, 4wd and has 4.56 gears on 33s..... but they stuck a plain jane Edlebrock performer intake on it. I feel it's limiting the engine quite a bit, so I acquired a holley street dominator for free essentially, thought I'd try it on there if it made a difference. Course I may open up the ports which from my research are the limiting factor of the street dominator and supposedly it comes to life when that work is done.

cam shaft is an Edelbrock, Duration 270, Lift .420/.420, holly 750 carb on top. Compression ratio is right at 10.5:1, just a shade under. Heads are stock with larger valves and an angled valve job done by a local racing shop. Cam is set 5 degrees retard. I forget what the total timing is. but it seems to fall flat after about 3500 or around 4000. Pulls hard till then. But when you're running 4.56 gears, you're RPMs are up there, which is one reason I don't drive it much. According to both my uncle and grandfather, the performer was the only intake they could find locally back then. we live in BFE with no performance shop options really, back then or now.

D.B.,keep what you have,unless you're sand dragging You never posted carburetor type,my man... That Street Dominator manifold's ,a keeper... Ignore the yahoo's,a basic street & strip car(1500 to 5000 plus,..) is a decent piece,just not here....

 

[AJ/FormS]

nm9
Agreed

 

[dukeboy440]

Ow, I forgot this is in a truck with that gearing. It is essentially a 3 speed on the street. IMHO, keep the duration on the lower end and widen the LSA if possible and keep the lift high. All in the name of keeping the torque curve as wide as possible. I think I would be looking at something like the Lunati Voodoo 3020070 to keep the lift from being too much, and look at your static CR to make sure it is not too high. BTW, have you run compression numbers on the engine so we can see if it really is close to 10.5 SCR? If not, we can be off in the recommendations.

Edit to add: I see AJ posted as I was writing this.... looks like the same thought process: wider torque curve to plan on a 3 speed operation on the street. The more I think about it, I think this is really going to wake up and be fun.

I have ran the numbers yes, i'll double check and report back. But those numbers were based on the sheet from the build shop with the piston part number, I havent measured them directly, no

D.B.,keep what you have,unless you're sand dragging You never posted carburetor type,my man... That Street Dominator manifold's ,a keeper... Ignore the yahoo's,a basic street & strip car(1500 to 5000 plus,..) is a decent piece,just not here....

Carb is a 4150 750 holley.

 

[AJ/FormS]

Since we know the displacement, and the ICA,( or at least can figure it from the cam description and the statement that it was installed 4* retarded),then If we had the cylinder pressure and the working altitude, it would be possible to "ball-park" the Scr pretty closely.
In any case without exact measurements and with the engine installed, there is almost no other way to figure it, short of pulling a head.
Man, somebody should make a tool for that!

 

[dukeboy440]

Well I'm just gonna sell this intake and get a new cam based on this. I'll pull the heads tomorrow and measure them. Was planning on new gaskets since it's been sitting any way

Since we know the displacement, and the ICA,( or at least can figure it from the cam description and the statement that it was installed 4* retarded),then If we had the cylinder pressure and the working altitude, it would be possible to "ball-park" the Scr pretty closely.
In any case without exact measurements and with the engine installed, there is almost no other way to figure it, short of pulling a head.
Man, somebody should make a tool for that!