The pro version allows more accurate modeling of the camshaft's rate of lift. Rather than the generic profiles standard with EA, EAPro allows you to input the cam's durations @ .005, .200, and .050. I modeled engines using both the Pro and standard versions and there is some variation depending on how aggressive the lobe profiles are.

 

ProFiler heads made in USA, and CNC ported by Chad Speier cost much less than comparable AFR heads and flow the same or more. Just under 300 CFM @ .6 lift @ 28 inches (dry flow) with 4.030" bore and 2.02" intakes. About 280 @ .5" lift.

 

The OP doesn't sound sophisticated enough to know what he's talking about RE: max power "needs" for his engine..................don't be too harsh with him. And, my apologies if I have offended the OP.

Most people don't know what they are talking about when they state their horsepower requirements. Most people on this board are older coots () whose only needs are for a slightly more powerful engine than existed back when these cars were new. They are not looking to embarrass a new Mustang, Camaro, Challenger or ZO6 Corvette. They simply want to take "the wife" to the corner grocery store to buy a dozen eggs and some milk.

If the OP wants to use dual quads and ram's horn exhausts, then throwing a lot of money at a build is a complete waste of time. He would be MUCH better served by using a 4.125" or larger bore and 4.00" stroke with pocket ported GM iron heads, and an L82 cam.

 

Not sure how you are going to get a 4.0" stroke small block.

The 3.85" stroke on my std deck height Dart Little M block needed a .050" smaller base circle cam so the rods wouldn't hit it, and I had to relieve the oil pan rails and dimple the oil pan a tad for rod clearance.

Here is a chassis Tq graph, we were doing AFR runs:

9.5:1,
4.185" bore, 3.85" stroke, (the bore size didn't need valve reliefs)
Mild hyd roller, I posted most of the specs earlier in this thread
1.62" primary long tube Heddman headers through full 2.5" exhaust (Borla muffs, and resonator cans, H pipe) out the back behind rear wheels, exhaust.
Dart Pro 1 CNC heads
Its a beast on the street in a 2800 lb car and its 15 lb flywheel.

As you can see, i need larger headers, and more height on the Vic Jr to extend my RPM range to take full advantage on the heads.

Doug

 

I started this thread asking about the subject cam thinking it MIGHT by chance be a possible choice for my build but probably not due to what I am doing.

OK, lets back up here a little and I will try to answer some of the questions/comments from those of you posting and also let me give you some personal info about me.

I no longer do my own work and even when I did I would not have built an engine like this myself. I don’t and never did have a machine shop. I have rebuilt stock engines but it has been over 30 years. I at one time owned an automotive repair shop but did not turn wrenches in it. I do not consider myself a mechanic but am mechanically inclined. I started in the car business in sales when I was 17 years old in 1968 so I have been around for a while. I have owned many high powered cars including a current 1966 Hemi Coronet that is blueprinted to NHRA stock specs and turns in the high 10’s so I have a pretty good idea of what “seat of the pants” h.p. feels like comparing it to the old original factory flywheel ratings and that it what I continue to reference, therefore it is pointless to talk about net h.p. to me. Many people in this thread are talking "over my head" with much of the technical responses also. Consider me a layman that knows enough to be dangerous.

I have used the link entitled “500hp 2 x 4 WCFB ! (well almost)” as a reference because I believe it is the closest type build to what I am trying to accomplish and what is capable with a 383 with my requirements which are as follows below. I will never bother to have the car dynoed so the 450-500 h.p. will never be PROVEN but I will have a pretty good idea if it is close or not.

1. When I open the hood I want the engine at first glance to appear to be a stock 283/270 dual quad engine without looking at numbers. So the heads will be camouflaged, and the reason for the dual quads and manifolds rather than header, plus the fact that I HATE headers for all of the obvious reasons in a street car.

2. I will be running the stock 9 fin valve covers with no mods for crank case ventilation therefore I bought a 327 block with draft tube. It is a casting number 3892657

3. The head manufacture will be Edelbrock E street series with supplied springs and these heads will take up to a 550 lift cam. Flow data here:
http://www.edelbrock.com/automotive/...low-data.shtml

4. I use this car for all around driving just as it would have been back in the day with the exception of driving it for everyday errands and on days it is raining. In other words I drive it around town, on the freeway, stop light racing and an occasional 1/4 mile drag race. This is NOT going to be a race engine and I am looking for a good all around high powered engine no different than say a WORKED 1970 LT1 or better. We all know those engines would hang with a 435 h.p big block back in the day.

5. I currently have 3.70 gears but will likely change to 3.08s as I believe with the added power I will have with the new engine I will be satisfied with the low end and it will be easier on the engine at freeway speeds. I am willing to give a little to get a little. However in the future I may change to an overdrive trans and then change the rear gears to something lower again.

6. Again the build will be a .040 over 327 with 383 crank, 0 deck 10.5 comp., aluminum heads port matched 2 1/2” ram exhaust manifolds , factory dual quad intake and carbs modified for max flow and port matched.

7. So the cam is the only unknown. I have communicated with Tom (DZAUTO ) about his build in his 1956 which is similar although his is a 400 SB with factory F.I. and he said his cam was a .510 lift and about a duration of 235 @ .050 in. He also said, "I am a big advocate of using roller TIP (NOT full roller) rocker arms (attached). You can spend the big $$$$ and go with Comp Cams roller tip rockers OR, use the rockers that look like stock rockers, but have a roller tip. Personally, for a mild/moderate engine, I feel those are quite adequate.
I have only used one major name brand cam in the past. Otherwise, I’ve used an “in house brand X” type cam from a vendor such as Summit. Summit (and others) usually have a very broad selection of cams/lifters that are MUCH cheaper than the name brands (most likely they are generic or clone copies of the name brands). I have NEVER had an issue with a “generic” cam. By now, all cams are ground on computer controlled machines and the profile is simply programmed into the cam grinding machine and whips it out."

8. I know the cam is really the heart of this build for me wanting a hydraulic 5800 rpm red line. So given the info I have provided I am looking for cam suggestions.

 

Not sure how you are going to get a 4.0" stroke small block.

I understand it can, and has been done with the "right" block with enough meat for reliefs needed for crank. I'd rather use the largest bore possible, with slightly shorter stroke. Here are a few examples:

http://www.speedtalk.com/forum/viewt...hp?f=1&t=45638

I'm sure you know places like Stahl's that can make you a set of 1 7/8 or 2 inchers. Or stepped 2" to 1 3/4".

I like the screaming short strokers, but one day my goal is to build a maximum size smallblock using 15 degree heads.

You have monster torque, for sure. Looks like fun.

 

Well, it really depends on what you mean by: "looks stock".

There are plenty of engines that "Look stock" but make huge amounts of power, and are quite streetable. The architecture that you choose to begin with will sap the potential of your build. The architecture of a dual quad setup just doesn't flow as well as a single, larger CFM 4 barrel. Once you put the air cleaner on it, it will be as "undetectable" as your "disguised" aluminum heads. Let's face it.............anyone who knows what they are looking at will spot it in a heartbeat.

It sounds like you are trying to save money, yet you are prepared to waste money on an expensive set of aluminum heads and then choke them with a plug in the intake and another plug in the exhaust. Makes no sense. Then you are going to remove a perfectly matched for 5 speed overdrive trans, 3.70 gear for a 3.08........and then later re-swap back the 3.70 which you shouldn't have removed in the first place and install a 5 speed? The difference in any car with a five speed is impossible to describe, but is startlingly dramatic. IMHO, you ought to do that before tearing into the engine if you have some money to spare. Hell, if you do that you might not feel the ned to make the engine more powerful......because you won't need to: not only will you have overdrive (perfectly matched to a 3.70 gear) but you'll have a lower first gear ratio................around 2.70 - 3.20 depending on what you use. So quicker acceleration and lower engine speed at cruise with resulting quieter driving and higher fuel economy. Money well spent! I would leave that 3.70 right where it is.

Cheapest way for you to "do" your engine would be to have your iron heads pocket ported with 3 angle valve seats (NO hardened seats), bore/stroke your 327 block out to 383, install a L82 cam and retard it 2 degrees. That cam is designed to work perfectly with 10.5:1 SCR (static compression ratio). Use a single 4 BBL carb, preferrably a 750 CFM Quick Fuel, and cover it with a drop base, Corvette air cleaner. Use a LT1 (Winters/GM) intake manifold. Set up your distributor with the most aggressive spark advance program that the engine will tolerate on (I assume) 93 PON fuel. Use 2 1/2" ram's horns into a low restriction set of mufflers.....like DynoMax.

FYI: I built a 327 engine that has plenty of torque for the street and so is VERY easy to drive, but, makes 480 net flywheel horsepower. It looks stock in every way except for the aluminum heads (which I chose not to paint/camoflage), and the headers which, BTW I like and are completely trouble free (if you know how to attach them properly to the heads). That's a specific power output of 1.47 HP/cu. in.

 

What I want to do is possible as you will see if you read the info here I am just not sure of what cam I want to use as this build uses a solid lifter cam:

https://www.corvetteforum.com/forums...ll-almost.html

I understand the challenges and the fact that I could much easier build a single carb engine to get the h.p. I have always liked Multi carb cars and the bling look. I am aware I could accomplish a better build with a single 4 bbl. and headers but that is not the look I want AND I have already purchased a 2x4 manifold and rebuilt clone carb as well a the 327 block.

Nothing cheap about any of this.

I am also aware of the choke points with the intake and exhaust.

Gear change may or may not happen.

Current engine is just a 220 h.p. 283 hence the need for the 383.

Just about as cheap to do aluminum heads then to buy and pay someone to work iron heads and the aluminum one will breathe better even with the choke points.

I had a 66 Corvette with a worked 327/350 with headers so I know what can be done with them.

 

I should say what a ranging thread this is. Well done, all.

 

Yeah, they some times get complicated and off track from the origin.

The real question here is what hydraulic cam red lining at 5800 will work best for this build with the known choke points? It will likely need a very specific certain lift and duration to make it work right but that is beyond my knowledge, hence the question. Everybody keeps suggesting a different build with single carb and headers. If I wanted to do that it would be easy as that has been done a million times, but that is NOT what I want.

I am thinking it will be a .510 lift and about a duration of 235 @ .050 in. unless someone else can tell me what would be wrong with it? But I am not sure if that is a hydraulic or solid lifter cam grind?

Another person I have communicated with told me this:
NO ONE designs HiPo modern cams with the intent of running cast iron exhaust manifolds.... i've been through this a dozen times with Lunati, Ultradyne, Bullitt, Comp, Crane etc. they all say "THIS SHOULD WORK FINE" but I always get better results with the OE grinds when using stock type exhaust manifolds.... now if you go to headers... then that is a completely different story.
This is one of the other battles here.
That is why I originally asked about the L79 cam.

 

I think that I need more duration to allow more time for air in/air out without screwing something else up?

 

Buy the Engine Analyzer program and qualify that thinking with an educated guess model.

 

OK, you have sold me on your knowledge.

Many of us here read that thread, as I did. Devildog is a very accomplished SBC guy and very knowledgeable, as well as a restorer of vintage aircraft!

If you are dead set on your build, and if you want to use a GM hydraulic cam, then I'd use the L82 cam retarded 2 degrees, with 1.6:1 rockers for a tad more lift.

If you want to use an aftermarket cam, then I (we) can recommend many. Flowrates for your aluminum heads at lifts from .1 to .6 would be helpful. If you go to the aftermarket, you should use a hydraulic roller. As mentioned before....if you want to "perfect it" then EA will let you do that. I (we) can make cam recommendations based on your SCR which will be close, but I can tell you that you will need a cam with low overlap because of your restricted intake and more importantly, your restricted exhaust. I (we) can specify a custom grind but something on 114 degree centers will probably suffice. The L82 cam has proper durations and low overlap, but the low lift will not take advantage of your heads' flow potential. In any case you will almost certainly need a custom ground cam in order to maximize torque/power from your build.

So, I (we) need two things before going further:

1. Your heads' flow at lifts .1 - .6
2. Are you willing to use a hydraulic roller cam? Aftermarket aluminum heads generally have extra high cover flanges to accommodate roller trunnions with stock valve covers.

 

You have a correct block for a stroker engine. Joe Randolph has done extensive research on what it takes to get a reliable bottom end with proper clearance on a 3.75" stroke ...657 block. Search for his posts.

There are hundreds of cams out there for SB Chevys. Determining the "ideal" lift and duration is a fool's errand. You only need to get it in the ballpark. Most aftermarket cams are designed for headers and open exhaust, so they have too much overlap for manifolds and mufflers that kills bottom end torque. The L-46 modest overlap is just right for a high performance road engine with manifolds and mufflers. It actually produces about the same power, all other things equal, as the LT-1 cam, but on a short stroke engine with massaged heads the lifters will pump up before the heads choke. On a long stroke engine that will not rev over 6000, it's just right.

The L-46 cam is a proven design that provides broad torque bandwidth from off-idle to at least 6000 RPM with OE valve train reliability, and as with any cam, top end power is a function of head flow.

The Edelbrock page shows dozens of SB heads by part number, and says nothing about E-series. Tell us the flow numbers of the heads you plan to buy. Also, the valve springs on those heads have waaaay too much force. The OE equivalent valve springs (F-M VS-677) will easily go to 6000 without pumpup, even if little attention is paid to proper installed height. Seat force is about 80 pounds and 200 at full lift with a 0.3" lobe.

Higher than necessary force springs will increase the possibility of lobe/lifter problems. If you use an OE equivalent cam like the F-M CS-1095R and OE equivalent VS-677 valve springs, you will have bulletproof OE valve train reliability.

Your desired configuration with the L-46 cam will have stump pulling low end torque that should easily pull a 3.08 gear unless you live in high mountain country. Depending on head flow peak power with the L-46 cam be in the 5000-6000 range and setting a rev limit of about 6000 is right.

A bigger cam will loose low end torque and move the peak power range to above 6000, which is above how high you want to rev it, so what's the point.

Search for a thread stated by me: "Tale of two camshafts". I was the system engineer on that project. We took a '57 283/250 FI engine and turned it into a stroker torque monster that made more top end power than the '61 Duntov-cammed, 461X head 283/315 HP FI engine. All the identifiable engine components are OE to that car. The "secrets" were all internal including a custom camshaft design, and the car went on to receive a NCRS Duntov Award.

Duke

 

Not true. Unless you are talking about a flat tappet cam. A bigger (meaning longer duration) flat tappet cam will "loose" bottom end/midrange because they are limited in their ability to increase lift without substantial corresponding increase in duration. Which is why the OP is limited to the L82 cam if he is wants a GM cam.

If the OP was using vintage iron heads, then the L82 cam would be sufficient. The OP is committed to aluminum heads, and for this reason his build needs a hydraulic roller to gain more lift at lower durations, which is the winning formula used by modern engines in order to get "stump pulling" torque at low engine speeds as well as higher power at high engine speeds. You correctly state that aftermarket cams are generally designed to be used with headers, which is why he should custom locate the lobe centers to minimize or eliminate overlap, gain maximum lift, and set the IVC location which matches his build's SCR.

 

I have sent my machine shop the above posts since I am getting two different suggestions here. Again you are asking me questions that are beyond my ability to answer so I am asking the shop for those answers. When I get them I will post them here.

In the meantime I would like to know the cam specs on the GM L82. I have Googled it but all the answers just talk around it and do not give the specific lift, duration and lobe separation.

 

I do not understand this? What would you have me analyze? Are you asking me to build an engine with some basic cam and then analyze it? Or just plug numbers into the program based on what I plan to build? I am not a "shop" just an individual that wants an engine built. I would have no need for a software program other than this particular engine.

 

I'd suggest you just buy the L 79 cam as was your original pick, stick it in the engine and be happy. Never mind all this smoke and mirrors stuff.

You might not make 500 hp but I'd bet you'll be happy.

 

I agree. This discussion is headed in a different direction that would waste a lot of time and money.

 

That wasn't so hard, one query on google "Chevrolet small block stock cam specs",a nd this was the second item on the first page.

http://www.kendrick-auto.com/chevrol...ory-cam-specs/

Doug