cam experts?

[Viperwolf1]

The duration at .050 is on the cam card and on the web sites for all the cam makers but what the card says and what the cam does is two diffrent things on a ots cam, never had a custom cam yet but thats gonna change soon.

If the cam doesn't match the card then you have the wrong cam or card or there's something wrong with your degreeing method or instruments. Don't rely on one single measure of cam phasing. Do it enough times so that the results are repeatable and you are comfortable with them. It's very easy to bump a degree wheel or pointer in the middle of the measurements. In my opinion the most critical point is in how you determine TDC. I use a piston stop that is adjusted as far down in the hole as I can get it.

 

[av bronco]

If the cam doesn't match the card then you have the wrong cam or card or there's something wrong with your degreeing method or instruments. Don't rely on one single measure of cam phasing. Do it enough times so that the results are repeatable and you are comfortable with them. It's very easy to bump a degree wheel or pointer in the middle of the measurements. In my opinion the most critical point is in how you determine TDC. I use a piston stop that is adjusted as far down in the hole as I can get it.

No, it's because big the cam grinders are not as accurate as the custom grinders. I have degreed sevrel cams in my life and the closest thing to the cam card was isky. the worst was Crower and my latest Comp cams is two degrees advanced more then it's supposed to. on top of the 4 degrees of built in advance if I dident degree the cam in I would have possably bent some valves. P.S. I have never seen a perfect cam set in by the timing marks.

 

[ft bronc]

I think it's been mentioned already on the thread, but the entire system has to be matched up well to get best results. It doesn't do any good to put a cam with 300 degrees duration in a motor that's restricted on either the intake or exhaust sides. By the time you get to the RPM levels that the cam is designed to work at, you either won't be able to get enough air in or get enough exhaust out. That creates all kinds of bad flow characteristics within the engine. Likewise, a high-rise single plane manifold won't work worth beans matched up with a 262 cam. At the RPM range the cam is designed to work at, the velocity of the air coming through the manifold won't be high enough to keep the "atomized" fuel suspended in it, and the motor won't run as well as it could with a dual-plane manifold with smaller diameter runners that would keep the incoming air velocity up.

My opinion is that most cams in the 262-272 range from the major manufacturers will work well for your application if they're matched up with the correct heads, intakes and exhausts.

 

[73azbronco]

Comp cams answer to my question why, seems they now use .05 in their new cams

I am not sure off hand why that particular lift was chosen but that has been the problem with advertised duration since the beginning and is why we now have duration @ .050. The @ .050 numbers let you compare cams from different companies. There is no set standard for where to measure advertised duration so most all the cam companies measure it in different places.

 

[blubuckaroo]

Well, I just might go back with an Edelbrock Performer cam or one of the generic ones like it. That's what came out of it and it ran pretty good. I'm not building racer, just want good pep. The car has power brakes and want to keep the vacuum up. With the Windsor JR heads it should pick up some flow there. I'm concerned that it might come pretty close to the 9.5:1 compression limit on that cam though.

 

[broncnaz]

The performer is a good choice and is relatively close in specs to all the other cams already mentioned.

 

[blubuckaroo]

The performer is a good choice and is relatively close in specs to all the other cams already mentioned.

The thing is that the valve springs on the Windsor heads is only 100 lbs at the seat. Most of the other cams need 110-115 lbs. I'm not oppose to changing the springs but these should work with that cam.

 

[DirtDonk]

That shouldn't even be a consideration I wouldn't think. No stumbling block at all. Because you're going to change the springs too.
Right?

Here's what I'm sayin'. I don't remember reading where you have new springs and don't want to change them out, or have new heads or what, so new springs are a no-brainer in my book. ALWAYS go with the spring recommended by the cam manufacturer. Wheter their springs, or someone elses that are less expensive, they should have similar specs.
Just don't put all this thought and energy into an engine re-do and not use new springs at the same time. Yes, stock ones are good quality. And yes, original springs with 200k miles on them can be found to be in good shape and the odd shim added here and there to bring a tired one up to spec. But you're never going to see the full benefit of any cam (even a stock replacement) on old springs. Period.

Sorry for the preachy tone there buckaroo, but now's not the time to scrimp on a relatively inexpensive part of the whole package that you're building.
It definitely falls into the category of "cheap insurance". Right up there with new battery cables. Only more expensive.

Paul

 

[DirtDonk]

Ok, re-read where you're willing to change the springs (got a little excited there for a minute). But again, unless the existing ones are new already, don't under-engineer the valvetrain.
At the very least, if they can sacrifice some travel, shim them up for a higher seat pressure to match the cam.

Paul

 

[blubuckaroo]

Ok, re-read where you're willing to change the springs (got a little excited there for a minute). But again, unless the existing ones are new already, don't under-engineer the valvetrain.
At the very least, if they can sacrifice some travel, shim them up for a higher seat pressure to match the cam.

Paul

Sorry Paul, I wasn't very clear. After I re-read my post I see where you are coming from.
Here's the deal,
The Windsor heads are new. They come with springs that have 100 lbs at the seat. They have more than enough lift for anything I would run. The Edelbrock cam requires factory 302 springs or their replacement which is 90 lbs. According to my machine shop my 100 lb springs are close enough to replace the Edelbrock recomendations. The other cams, I have listed in previous posts, need anywhere between 110 and 120 lbs.

 

[TDubya]

Well, I just might go back with an Edelbrock Performer cam or one of the generic ones like it. That's what came out of it and it ran pretty good. I'm not building racer, just want good pep. The car has power brakes and want to keep the vacuum up. With the Windsor JR heads it should pick up some flow there. I'm concerned that it might come pretty close to the 9.5:1 compression limit on that cam though.

The Crane H-260-2 cam that I have works very well with my set-up: Holley 600cfm, Edelbrock Performer, stock heads w/ Crane recommended springs. Sounds very similar to what you're running, except that you have better flowing heads. I have great vacuum at idle and is very responsive. I have to say that the recommendation from Crane 12 years ago was right on.

 

[broncnaz]

Contact world products and get the specs of the springs Most of the time you can shim or unshim the springs to give the required pressure. I Probably wouldnt sweat a 10 lb differance(with new springs) as most springs will also have a break in period and lose up to 15% of seat pressure after break in. The main place weaker springs will show up is at high RPM's

 

[blubuckaroo]

Summit just replied with this suggestion. Input?

Brand COMP Cams
Manufacturer's Part Number CL31-216-2
Part Type Camshaft and Lifter Kits
Product Line COMP Cams High Energy Cam and Lifter Kits
Summit Racing Part Number CCA-CL31-216-2

Cam Style Hydraulic flat tappet
Basic Operating RPM Range 1,200-5,200
Intake Duration at 050 inch Lift 212
Exhaust Duration at 050 inch Lift 212
Duration at 050 inch Lift 212 int./212 exh.
Advertised Intake Duration 260
Advertised Exhaust Duration 260
Advertised Duration 260 int./260 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.447 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.447 in.
Valve Lift with Factory Rocker Arm Ratio 0.447 int./0.447 exh. lift
Lobe Separation (degrees) 110
Intake Valve Lash 0.000 in.
Exhaust Valve Lash 0.000 in.
Grind Number 260H
Lifter Style Hydraulic flat tappet

Increase your street machine's gas mileage and powerband performance!
COMP Cams High Energy cam and lifter kits are designed for street engines with an 8:1 to 9:1 compression ratio. They also work well with all stock components, including intakes, exhaust manifolds, and carburetors

 

[broncnaz]

very tame cam well suited for a 4x4 although I would consider something a little bigger closer to the the edelbrock performer cam or slightly bigger than that especailly if your going to do any hiway driving without a OD.

 

[av bronco]

Make sure you follow the flat tappet break in proceedure and use good break in oil with zinc.

 

[blubuckaroo]

very tame cam well suited for a 4x4 although I would consider something a little bigger closer to the the edelbrock performer cam or slightly bigger than that especailly if your going to do any hiway driving without a OD.

What do you mean by bigger. Lift? Duration? What cam would you consider "slightly bigger" than the Performer? Yes some of my driving is in the 2800-2900 rpm range.

 

[broncnaz]

Mostly duration lift has little to do with powerband. The only reason to pay attention to lift is to ensure your valve springs will handlle it and piston to valve clearance is ok.
I run this crane cam with good results. Its a little bigger than a performer. good for hiway cruising and lowend is great as well. I really like cranes spec cards as they give some info that others dont. http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=363931&lvl=2&prt=5

I've also ran this cam in the past its a little bigger yet but would have good power if your always in the 2500 rpm+ range. If my stock cylinder heads had been rebuilt correctly I probably would still be running this cam. i thought about reinstalling it when I put on my TFS heads but it was in storage 800 miles away at the time. http://www.cranecams.com/index.php?show=browseParts&action=partSpec&partNumber=363941&lvl=2&prt=5

 

[TDubya]

x2 on the Crane H266 cam. I'm running the H260 which was matched to my gearing at the time (3.50 w/ 31" tires). I could use a little bigger cam with my current 4.10s and 33s, but I'm still pleased with the performance.

 

[blubuckaroo]

Mostly duration lift has little to do with powerband. The only reason to pay attention to lift is to ensure your valve springs will handlle it and piston to valve clearance is ok.
I run this crane cam with good results. Its a little bigger than a performer. good for hiway cruising and lowend is great as well. I really like cranes spec cards as they give some info that others dont. http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=363931&lvl=2&prt=5

I've also ran this cam in the past its a little bigger yet but would have good power if your always in the 2500 rpm+ range. If my stock cylinder heads had been rebuilt correctly I probably would still be running this cam. i thought about reinstalling it when I put on my TFS heads but it was in storage 800 miles away at the time. http://www.cranecams.com/index.php?show=browseParts&action=partSpec&partNumber=363941&lvl=2&prt=5

Yes the advertised duration on the Crane is a bit less than the Edel but @ .50" it is a bit more. I'll be using World heads with 1.94" in and 1.60 ex. Will that affect to outcome? I maen, could a bigger cam cause it to be more boggy?

 

[broncnaz]

Yes a bigger cam could cause the low end to be boggy. Your heads are not big enough to cause boggyness. Better heads only allow the powerband to move up a little or extend it a little. If you had some full race heads then it might cause a issue but really all the cam choices so far are fairly mild I doubt even "big" heads would cause any issues.
I run the 266 cam in my 302 with TFS heads 2.02/1.60 valves and it runs great no boggyness anywhere. I also run 33in tires and 3.50 gears, NP435 and get 17mpg with this combo.