Custom vs Catalog Cams

[CamKing]

How many of you that are ordering custom cams actually spec the cam, how many rely on the company's expertise?

None of my customers do.
If someone calls me, and lets me know that they "Know" more about what their engine needs for a cam, I politely send them on their way.
From my experience, those are the guys that will take all the credit, if it works well, and blame the cam company, if it doesn't.
I want as much information about the engine, as the engine builder can give me, including any experience with other cams.
The data I collect in a year, on how engines react to cam changes, in a multitude of different applications, is more then most engine builders will learn in a lifetime.

[CamKing]

How do you (you personally) decide when to go with a catalog cam or have a custom cam made?

How do you evaluate a cam listing that does not include important information about the design such as acceleration values and a graph of the curve?

If, for example; you were buying a hydraulic roller for an 454 BBC, what would bring you to the conclusion that the catalog cams did not provide what you need?

How does price figure into the decision for you?

IMO, there are only 3 reasons to buy a catalog cam.
1: Price
2: You need it tomorrow.
3: you're building an engine package that you've built before, and you know what the cam will do.

[LoganD]

Most cam companies have precisely zero experience evaluating cam lobes for durability, things like assessing asperity contact for different oil types and valvetrain deflection just aren't within their capability. Thus, I tend to spec everything myself, even the lobe design. I use LSM.

[RevTheory]

Jon, are we answering your question in the manner you'd intended?

That's not a snarky comment; I'm curious to see where you're headed.

[CamKing]

In my 30+ years, I mass produced 2 different cams to sell. One was for the Richard Petty Driving Experience, where they needed about 75 cams a year, all the same.
The other was a hydr flat tappet cam for a 350 Chevy with iron heads, 9-10:1 compression, Edelbrock performer manifold, headers, 650 carb, 5,500rpm power peak. It was something we developed to make 400+ft/lbs, and 400+hp, and was dyno tested in multiple engines. Since that engine combination was so popular in the 80's and 90's, it made since to have them sitting on the shelf.

[Roundybout]

Off the shelf cams are designed and have to take into consideration all the variables that might come into play in a typical build. I always laugh at "will work with 265"-400" SBC, 1500-5500 RPM range, choppy idle, gear and higher stall recommended." That one cam will perform very differently in a 302" compared to 400" engine. Now add one guy using a Victor Jr with a 750 carb and another guy a dual plane and 650 carb, 2 points difference in compression ratio and differing exhausts and yet that cam is "supposed" to work with all that. It may or may not be a perfect match at some hypothetical build spec, might be close or just plain way off from optimum. You can build around known cam specs and have great results but when the cam is designed around how the actual engine is built you'll get much better results. That's where a custom cam spec will shine. He/she will get as much info as possible, the more the better and be able to recommend what works from past experience, testing and results from similar builds. A good cam designer can be 90% there or even spot on the first time getting you maximum performance from your assembly of selected parts you've chosen for a build.

[Orr89rocz]

you're building an engine package that you've built before, and you know what the cam will do.

Lot of late model engines fall into this. L98 LT1 type efi small block chevys. Internet forums out there have many hundreds if not thousands of posts showing dyno and track results of ppls builds using shelf cams. Alot of them work very well

Like comp cams xfi series hyd rollers. The 280xfi cam 230/236 .570’s on a 113. Works fantastic with Afr 195cc or equivalent heads in a 355-383 up to 6500 rpm with the right valvespring and Short runner efi intakes. Guys wanting 350-425 whp ish which is common request, this gets job done

Only thing is i’d opt to have it on a billet core for 400-425 lb open pressures.

Or the old lt1 world, comp cc306 or their 8-503-08 cc503 cam. Soft lobes that sound good and make power. Tried and true, satisfies alot of requirements ppl want for street car

Ls1 stuff esp alot of “custom” grinds became shelf grinds and flat out work. Ls stuff seems to not be picky on specs

Outside that, custom for more custom builds or more max effort stuff

[CamKing]

Internet forums out there have many hundreds if not thousands of posts showing dyno and track results of ppls builds using shelf cams. Alot of them work very well

Yes, if your goal is to be only as good as someone else.
If you want to build something better then someone else's engine, you need to go with a custom cam.
Personally, I would never go to all the effort of building an engine, to try and be "Just as good".

[RevTheory]

Speaking LS engines, one thing I find interesting is that the cam catalogs and the internet are loaded with cams on 113+ LSAs and then SAM comes in with an EMC entry on a 104 and builds monster torque right out of the gate that carries out through the full pull. And who can forget Kaase's 98 +6, although I forget the engine he built that year.

I'd like to know more about their tradeoffs between competition and actual car on the road.

[CamKing]

Speaking LS engines, one thing I find interesting is that the cam catalogs and the internet are loaded with cams on 113+ LSAs and then SAM comes in with an EMC entry on a 104 and builds monster torque right out of the gate that carries out through the full pull. And who can forget Kaase's 98 +6, although I forget the engine he built that year.

I'd like to know more about their tradeoffs between competition and actual car on the road.

The EMC rules, and they're scoring that heavily favors power below 5252rpm, require a cam that's not what you would normally run in a street engine.

[Orr89rocz]

Internet forums out there have many hundreds if not thousands of posts showing dyno and track results of ppls builds using shelf cams. Alot of them work very well

Yes, if your goal is to be only as good as someone else.
If you want to build something better then someone else's engine, you need to go with a custom cam.
Personally, I would never go to all the effort of building an engine, to try and be "Just as good".

I agree but how much more can you get for that price and time? Not that its much more in cost but for a typical street 355-383 guy, using most shelf type heads in the 190-200 cc range, hyd roller, sub 7k rpm, low maintenance etc, how much more power can you expect?
For other applications and use, i suppose theres more merit.
So many guys come into my friends shop and ask i want 400 whp or 450 whp from their late model lsx stuff. So many guys want 500 hp sbc. Some shelf recipes just work fine for that.

[CamKing]

Internet forums out there have many hundreds if not thousands of posts showing dyno and track results of ppls builds using shelf cams. Alot of them work very well

Yes, if your goal is to be only as good as someone else.
If you want to build something better then someone else's engine, you need to go with a custom cam.
Personally, I would never go to all the effort of building an engine, to try and be "Just as good".

I agree but how much more can you get for that price and time?

In most cases, 20hp or more, but there are many people who will never miss that 20hp.

[RevTheory]

Speaking LS engines, one thing I find interesting is that the cam catalogs and the internet are loaded with cams on 113+ LSAs and then SAM comes in with an EMC entry on a 104 and builds monster torque right out of the gate that carries out through the full pull. And who can forget Kaase's 98 +6, although I forget the engine he built that year.

I'd like to know more about their tradeoffs between competition and actual car on the road.

The EMC rules, and they're scoring that heavily favors power below 5252rpm, require a cam that's not what you would normally run in a street engine.

Yes. My question, I guess, is why? Do those cams simply refuse to be dropped into gear or do they make the throttle act more like an on/off switch or do they just over-torque the traction capabilities of a street car or what? Are they just a miserable prick to drive around?

[plovett]

Speaking LS engines, one thing I find interesting is that the cam catalogs and the internet are loaded with cams on 113+ LSAs and then SAM comes in with an EMC entry on a 104 and builds monster torque right out of the gate that carries out through the full pull. And who can forget Kaase's 98 +6, although I forget the engine he built that year.

I'd like to know more about their tradeoffs between competition and actual car on the road.

The EMC rules, and they're scoring that heavily favors power below 5252rpm, require a cam that's not what you would normally run in a street engine.

That is the main reason I stopped following the EMC. They count torque twice. Once as torque and again in the horsepower. It is silly.

That and pandering to the largest demographic via rule changes.

JMO,

paulie

[CamKing]

Yes. My question, I guess, is why? Do those cams simply refuse to be dropped into gear or do they make the throttle act more like an on/off switch or do they just over-torque the traction capabilities of a street car or what? Are they just a miserable prick to drive around?

Because they don't make the most average power, thru-out the RPM range of the engine. They sacrifice power above 5252, for power below 5252, because it will score higher.