Cam suggestions

I would like any input on select a cam. It's going to be a weekend driver I'd like to do 5000 rpm time to time has a auto trans. My motor is a 66 200 block 77 head in the process of porting it now has the exhaust runners almost all blended and smooth, I will blend the intake how far do I smooth if at all? Has 3-4 port diverder. Thinking I'll install the 1.468 values from the 144 in the exhaust, has anyone done anything with bigger valves? Modified the intake to a two barrel carb. Has a hei dizzy will run it for now may change later. Will run the vintage inline header. Have 1.6 adjustable rockers. Compression will be 9.5 to 10 no major machine work has been done yet. I'm not sure of which cam, spring setup the ford six book does say a lift over 420 is pointless without major changes which I think I have done. I want I'm thinking of vintage inline csc-264110 duration 264/264 lift 450 lobe 110. Or compcams 65-236-4 260h duration 260/260 lift 440 lobe 110. Any input is greatly appreciated. Thanks in advance.

First if you have the stock stall converter, stay away from the 110 L/C cams if going over 260 degrees of duration.
Don't get the Comp 260 cam cause its a antiquated design.
The CSC 264 with a 112 L/C & better springs or call Jerry at Schneider cams for some more info.
Get as much lift as possible. Remember if you have over .440" lift you will be hitting the max flow twice, once opening & second upon closing. Yes the flow at very high lifts maybe slightly lower at that point, but you will have more area under the curve.
For valves i would get the SI valves from vintage inlines.
The Ford DS11 distributor with a MSD-6al ignition is a better combination than even the HEI. Do not get the DUI cause it has shaft oiling problems plus other problems.
Get your distributor recurved for your engine combination. That will be a major gain in performance & overall drive ability.
Get a set of headers, the best is Hookers to a dual exhaust system with a X pipe or a crossover pipe. If you can't afford them there are other choices.

Howdy All:

My suggestions are not far from WSA111 but I thought I'd add my two cents too. I'd sure look into VI's 1.5" exhaust valves. They may be close in price to the old 144 intake valves for your exhaust. Check it out. I used the 144s back in '02, before I became aware of the stainless steel valves, which in my opinion, are a better way to go. Make sure your machinist adds a back-cut to your intake valves.

On the cam, either is a good choice but with an auto trans you will want a wider cam lobe separation to improve vacuum and compliment your auto trans. On the cam lift, I'd recommend that you get the lift you want from the cam and get the manufacture's recommended valve springs.

On the ignition, if you already have a DUI system have the advance curve redone to match your cam and situation.

What carb are you planning on using? Keep us posted on your decisions and progress.

Adios, David

David, i believe you have covered the most important items.
On the intake valves, lap them in to the seat & then use a 30 degree back-cut to the lap in point for a significant amount of flow.
Another plus would be to weld in oil control baffles in the oil pan.

Thanks for the replys. With the 1.5 exhaust valve would it be shrouded by the chamber? And your opinions on this clay smith cam 264/264 duration .441/.441lift 112 lobe center 2000-5700 rpm? On my carb it's currently a webber 32 36 on a 1 barrel adapter so with making the head a 2 barrel it might need to be re jetted.

Howdy Back 4-5 Mustang:

Shrouding is not an issue on the exhaust side. The exhaust gases are being forced out of the cylinder in a high pressure, explosion-like environment, so shrouding is not a problem. Shrouding is an intake problem, especially if you were to attempt to use an intake valve bigger than a stock, late model, 1.75" diameter head valve.

The machining of the valve seats as Bill described will get the most in valve airflow.

The Clay Smith cam is right in the same camp as the others. Be sure to compare the @ .050" lift specs as well. As BIll alluded to, there is more to cam lobe design than the numbers. If you think of the cam lobe as an oval egg shape, then note that some eggs are more pointy while other a more round. Modern cam lobe designs tend to be more round. In this case the .050" spec will be a higher number. That gets the valves opening quicker and staying open longer through the opening and closing cycles. It pays to study, compare and shop.

On the valve lift question, more is not always better. I prefer to get valve lift from the cam, using a stock type adjustable rocker arm for a street type engine. There are several reasons for my preference. High lift rocker arms may be a good way to get more lift from a stock type cam, but they do add to side loading the valve as well as adding stress and possibly coil bind to the valve springs. If I were spending that kind of money for a rocker arm upgrade I'd be looking at roller tip rockers. The roller tip reduces side load and friction. Finally, going from a 1.5:1 rocker to a 1.6:1 rocker arm will only add approximately .030" lift to the valves while adding stress to the rocker and shaft. PS- be sure to thoroughly clean the inside of your rocker arm shaft in the course of your rebuild.

Lastly, your carb choice may be a limiting factor in your engine project. Which Weber is the one you are using? Is it a staged or staggered opening type? What is it's total cfm flow rating? Direct mounting will help it. But, I would suggest that you build your carb mount so that you will have the option of a carb capable of more performance. And yes, rejetting, as part of the tune, will be likely with your new engine.

Good luck and, again, keep it coming.

Adios, David

WSA111 small subject change, your opinion on the Pertronix 3 for small block (250) Ford six?

hotrodguy":14nde1op said:

WSA111 small subject change, your opinion on the Pertronix 3 for small block (250) Ford six?

Click to expand...

The Pertronix 1 is a good product. The 11 was junk. I have no knowledge on the 111 unit.

The description of the cam lobe as a egg is a good one. I'll take a closer at the .50 numbers. I'll have to look up the cfm of the webber it's progressive. If that doesn't go i have a 230 cfm holley 2 barrel collecting dust.

HOwdy Back:

It's the spec at .050" that will be listed. That's what you will need to look at for comparison between the cams you are looking at.

I don't think it has been covered yet, but I'd sure recommend a double roller chain timing gear set while you are doing the cam.

Keep it coming.

Adios, David