Cam Recommendations?

[dcdoug]

Yes I have the solid lifters and they are in the order they came off the lobes. The lifters are Holman Moody solid shell type hollow lifters.

As for the cam, I loved this cam on my standard bore/stroke 427. It had a great loping idle, wasn't too wild and was easy to drive - but was great at WOT too. It did have a fair amount of overlap though, so it didn't like to be lugged, but that was only an issue if I was too lazy to downshift in heavy traffic and I never found it to be a big deal.

Here's a few vid links:

Start-up on an engine stand: https://youtu.be/EUBzCll5Cg0

Autocrossing in 2nd gear: https://youtu.be/ifiZnPmcvKU

I wouldn't replace the cam, except now that I've had to do a clean-up overbore AND found a hairline crack in my crank, I'm changing to a stroker rotating assembly resulting in a ~482. Brent tells me my cam will feel like a RV cam in the new motor.

I did tell him I wanted to come up with a comparable grind for the new motor with the one addition that he could tweak it for autocrossing duties as I'm doing more of that now that I was before.

[eschaider]

Originally Posted by FatBoy

I've never had to spec a cam before, so are you able to elaborate a little please?

"more split between the duration" does that mean more or less duration, or something else?

With regard to the lobe separation, do I need to be looking in the 110-112 region? What does changing the lobe separation do and is it the inlet that is opening later, or the exhaust that is opening sooner or a bit of both if I reduce the LSA?

Whilst I'm more than happy to accept your experience, I do like to understand why I'm doing something.

ATB,
Paul

Paul,

I have attached a zip file with a browser application (runs like a page in your browser) that will help you visualize the effect on opening and closing events that duration, centerline and LSA (Lobe Separation Angle) has.

The app was written by a good friend of mine, Mark Olson, and is free for all to use.

Installation procedure:

Unzip all 4 of the files in the CamChart.zip file into the same directory.

The files are:

CamChartCandDr1.htm
CamChartOandCr1.htm
wz_jsgraphics.js
CamChartReadMe.txt

How to run the program:

Make sure Javascript is enabled in your browser's options.

Double-click on either of the .htm files.

If the browser asks if you want to "allow blocked content", run a script or allow an active control, click "yes".


The app essentially lets you create a cam card for any cam you wish to that will illustrate the effect on valve opening and closing points that duration, centerline and LSA have.


Ed


Ahhhh, the forum will not allow zip files greater than 39KB. This zip file is 745KB. PM me an email address and I will send it to you by email.

BTW this is what the output looks like. For some reason the CC image comes up fuzzy but the actual screen image is sharp.

[Shootnride]

Paul,

I personally think one of the most important aspects of cam selection that is often overlooked, is dynamic compression. If you're not familiar with what dynamic compression ratio is, there are some pretty decent articles on the web. Here's one :
Dynamic Compression - Hot Rod Network

Ted

[eschaider]

For those who would like a copy of the s/w here is an alternative way to get it if you want.

Go to => CamChart s/w and download it from the post that you will see over there.


Ed

[FatBoy]

Hi Doug,

Can you drop me a PM and let me know how much you want for your cam and followers please. One big advantage of your cam is that it has already been run in, so I wouldn't have to go through the stressful breaking in process.

Paul

[dcdoug]

Originally Posted by FatBoy

Hi Doug,

Can you drop me a PM and let me know how much you want for your cam and followers please. One big advantage of your cam is that it has already been run in, so I wouldn't have to go through the stressful breaking in process.

Paul

Will do. I'd be happy to see it go to a good home.

[Gaz64]

Originally Posted by Shootnride

Paul,

I personally think one of the most important aspects of cam selection that is often overlooked, is dynamic compression. If you're not familiar with what dynamic compression ratio is, there are some pretty decent articles on the web. Here's one :
Dynamic Compression - Hot Rod Network

Ted

Yes, that is why the inlet closing timing point is the most important event of the four opening and closing points.

[FatBoy]

I've exchanged a few PM's with Doug and it looks like his HM cam may well have found a new future home. Using Doug's cam has the added advantage that it's already been broken in, so I won't have to go through the stress of doing it myself.

This will be my winter project, so I'll keep you posted.

Paul

[patrickt]

Originally Posted by FatBoy

I've exchanged a few PM's with Doug and it looks like his HM cam may well have found a new future home. Using Doug's cam has the added advantage that it's already been broken in, so I won't have to go through the stress of doing it myself.

This will be my winter project, so I'll keep you posted.

Paul

Good. Of course, there's a $200 additional fee for him to individually label each lifter with 1I, 2E, 3I, 4E, etc....

[blykins]

I would still use a small break-in period.

Yes, the lifters have been burnished to that camshaft, but the lifter bore positions vary from block to block, and even the lifter bore clearances vary.

A lot of guys buy cams already broken in from Cam Research, since they have a "cam break-in machine" and I have heard of several instances of the cams failing even after that procedure.

Not trying to be a negative Nancy, but just urging you to be cautious.

[FatBoy]

Point taken.

[A98Coupe]

Paul,

I recommend you stop using Valvoline VR1. It doesn't have sufficient ZDDP. It's probably why you lost you cam eventually. You need to switch to a proper performance oil. Joe Gibbs Driven hot rod oil is the only way to go. Take a look at the Anglo American Oil website and all will be explained. They are the UK distributer for Joe Gibbs & Sunoco racing fuels.

[FatBoy]

Hi Stuart,

I've been using VR1 specifically because it has high levels of ZDDP. Many people swear by it and you're the first person I've heard question its suitability. What level of ZDDP do you think we need in our engines?

It's even been suggested that I just use a good quality diesel engine oil, so it is really difficult to get definitive advice when it comes to oil. I even called Opie ould and spoke to one of their technologists and he fundamentally said that "high" ZDDP content oil was just marketing bull**** and that any good quality oil would have sufficient levels. Then there's the whole mineral vs. synthetic argument. There is a synthetic Mobil 1 that has higher levels of ZDDP, which has been recommended.

I don't know why my cam failed, but I could reasonably have argued with all conviction that VR1 was "the only way to go" based on 30,000 miles of trouble-free motoring, right up to the point when it failed.

I'll take a look at the website and read with interest.

Thanks,
Paul

Paul

[patrickt]

Here's a VOA for Valvoline VR1 from 2016. https://bobistheoilguy.com/forums/ub...pics/4177567/1 These values for zinc and phosphorous, if accurate, are too low for solid flat tappet cams. Now, the VR1 data sheet lists the values as higher (0.14/0.13). Most SFT guys nowadays go with either Joe Gibbs or Brad Penn exclusively. I use the latter, and you can order either brand off of Amazon, even if you live in the Arctic Circle.

[Shootnride]

Here is a link to a VERY lengthy article that one SAE engineer wrote on his testing of hundreds of oils. If you get to the last portion of the article he ranks all of his tests with results. In his testing he ranked the Valvoline VR1 at #36 and the Joe Gibbs Hot Rod at #97. It's an interesting read. You can make your own opinion about his testing.

https://540ratblog.wordpress.com/201...-test-ranking/

Ted

[patrickt]

I forgot to mention that I also add a bottle of the original GM EOS, not the stuff they changed to about five or six years ago and then kept the same name. I still have a case of it. That's probably the equivalent of that author's "Oil Extreme Concentrate" stuff, which bumped the BP rating up to the #20 slot.

[olddog]

Originally Posted by Shootnride

Here is a link to a VERY lengthy article that one SAE engineer wrote on his testing of hundreds of oils. If you get to the last portion of the article he ranks all of his tests with results. In his testing he ranked the Valvoline VR1 at #36 and the Joe Gibbs Hot Rod at #97. It's an interesting read. You can make your own opinion about his testing.

https://540ratblog.wordpress.com/201...-test-ranking/

Ted

This is too much to read in a reasonable time, but it sure is interesting. Thanks for the link.

In short, I find this to be the best information I have ever found. It fits with everything I have experience with, with one exception (later). His chosen test method, in my opinion, is exactly what you need to know about cam failure.

I have often said I believe there is something to the ZDDP, but I am not convinced that everything said is gospel. This data shows that it is not ZDDP alone, and I believe his tests are accurate.

He states that oil is not compressible. It is typically stated that polymers are like oil and are not compressible. I do know that polymers are compressible. It is very little, and it takes a lot pressure. It doesn't matter at small volumes, but it can with vary large volumes. I suspect a large volume of oil at a high pressure will slightly compress as most things will. Now that said this is a technical point for geeks and clearly not the audience the data was intended for, and will not matter in an engine. For all practical purposes, this guy is spot on, on everything I read. I only made this point, because someone always wants to criticize on some technicality, for various motives. Sure nothing is perfect, but I really think this is the best information out there and only a fool would attack it.

[patrickt]

FWIW, Brad Penn oil is the Kendall oil that we all knew as kids. It's green, and always has been green. The Kendall oil they sell now is not the Kendall oil of yesteryear. The GM EOS that they sell now is not the GM EOS that they sold many years ago. The "classic old school" oiling method that everyone I ever knew, and who is still alive, used back in the day for a SFT, and before ZDDP was a household word, was to use Kendall oil with a bottle of EOS. But, if you just trot to the auto parts store this afternoon and brought home Kendall Oil and a bottle of GM EOS, it would be completely different from what it once was.

[FatBoy]

Originally Posted by Shootnride

Here is a link to a VERY lengthy article that one SAE engineer wrote on his testing of hundreds of oils. If you get to the last portion of the article he ranks all of his tests with results. In his testing he ranked the Valvoline VR1 at #36 and the Joe Gibbs Hot Rod at #97. It's an interesting read. You can make your own opinion about his testing.

https://540ratblog.wordpress.com/201...-test-ranking/

Ted

Ted,

That's very interesting (and VERY long) article, thank you for posting the link. It pretty much confirms what I was told by the techs at Opie Oils, in that ZDDP is just marketing nonsense and bears very little relationship to the actual wear protection capabilities of the oil.

I haven't read all of it (obviously), but I didn't see anything specifically in regard to oil weight. Could I use a 10W40 oil, or even a 0W40?

I liked the idea of the Valvoline Maxlife High Mileage, because it has extremely good wear protection characteristics but also has additives to minimise oil leaks, which has to be a good thing. What wasn't so appealing was the price here in the UK at over £70 for 5 litres. However, if the oil change intervals could be extended to 2 or 3 years, it looks like much better value. Presumably a full Esther synthetic isn't going to degrade and form sludge deposits like a mineral oil.

Paul

[Shootnride]

Originally Posted by FatBoy

I haven't read all of it (obviously), but I didn't see anything specifically in regard to oil weight. Could I use a 10W40 oil, or even a 0W40?

Paul,

In Section 2 of this article, the author goes into selection of the proper oil viscosity. Basically, he promotes using the lightest oil that will still maintain adequate "hot" oil pressure for your particular engine. He says that the old rule of thumb of 10 psi/1000 RPM is a reasonable standard.

So, based on his recommendation, I suppose each engine would require a bit of experimentation, because all engines are not built with exactly the same bearing clearances. I think at my next oil change I'm going to try changing to a 10W30 and see how it works out. My engine runs pretty high oil pressure even when hot and I'm currently using a 15W50 oil.

Ted