Scat c-45 camshaft, what is actual duration? Torben?

[modok]

I have a very OLD scat c-45 cam and decided to degree it today.
I found it has nice long .012 or so lash ramps more like WEB than engle, which is good!
The intensity is low enough to use 1.25 or even 1.4 rockers no problem. at .050 I found 254 degrees. It is on a VW blank, and very small base circle, not sure if I actually want to run it, maybe I get a newer one.
So I look at the catalog and it says the c-45 is 262 @ .050, so they changed it?
BUT, look at the cam card, it says 262, but do the math, 19+55+180=254

https://www.thesamba.com/vw/gallery/pix/602924.jpg
SO..........is 262 a typo?
Several of the numbers don't add up right on the other cams too.
Very shameful.

Has anyone degreed a newer c-45, what numbers did you get?

[vwracerdave]

I have a very old cam list the shows the C45 has [email protected] and the C95 has [email protected]. Maybe somebody got the 4 & 9 mixed up in typo.
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[Alstrup]

Hello.
I have not had a C45 through the cam analyzer. Only dialed it in in a case. I have noticed, as you, that the C45 is somewhat low compared to the advertised figures. They usually mic out at about 293 - 295 seat, 256-257 @ 0,050" and 108 LC and hovering in the 0,388 -0,390" cam lift.
The old ones, like you have is ground on a std billet, which results in a rather low base circle. But I wouldnt worry. Use VW lifters with it.

The C45 pulls "flatter" compared to say a W120. It works very well with 1,3 rockers if the engine can exploit the extra air. Even 1,4´s, but then I would absolutely recommend ally PR´s, or the valve train noise becomes a little too much for my taste. I like it. In fact I have had better results with the C45 than the W120 when it comes to power. But then again, I never was an Engle guy.

Be aware that if your port volume is on the high side for the displacement, especially your exhaust side and header, you would do wisely in installing the cam on 106 ILC, or you might run into a stumble in the progression rpms (1700 - 2000) That can be rather annoying. (It is more sensetive to that because it is not ground advanced)

T

[modok]

Thank you Torben.
Most likely the cam cards are a mistake.
ACN website has .050" duration listed as 254.

I have a set of old eaton lifters that could go with it, to make a great vintage set! I would run 2-4 degrees advance.

What I want to do is have a web 110 with more intake lift, but the web110 has very high intensity so I don't think 1.25 rockers should be used with it.
And if web is using different cam blanks....... everything is changing.

Refaced and cryo treated scat lifters worked OK for me 10 years ago, maybe I'll try that again. If nobody can grind a cam good enough to run I guess I'll use these 30 year old parts LOL

[Alstrup]

Erhm, youre a bit wrong with the Web 110. It is actually quite OK on the ramps, also with the use of 1,25 rockers. With Oteva sgl HD springs, Ti retainers and ACN ally pushrods I have no problem spinning 65-6600 rpm.
Oteva´s are of course not readily available in the US, so Racemaster duals might be in order. They are about 280 lbs over the nose which is plenty.
The C45 is somewhat "worse". Same set up with that and you get valve float around 6500.
With the C45 and 1,3 rockers you do get about 0,018" more valve lift over a Web 110 with real 1,25´s and if the engine can exploit the extra lift/flow you will get a tad more power.
Eaton lifters should be fine.

T

[modok]

You may be right.
The data I collected of the ramp area of the scat cam is somewhat "wavy", I do not know if this is measurement error, crust from old age, or just because it is a crude profile.

I will graph the ramps of both in greater accuracy, and compare.

[modok]

zero to .100 lift
Degree wheel was timed so they are both synched at .100 lift, which is off the chart, but that's how I do it.

web is red, scat is black

Just looking at the graph you might conclude the scat is merely a poor quality copy The bumpy the acceleration ramp are there on all lobes, while the web is smooth as silk! If it wasn't for the bump it would be a smoother cam, but the bump IS there at .023 lift. What is that??

And so much for the intesity being less on the c-45.... they both are almost the same.
If I synched them at .050 lift the c-45 would be a few degrees fatter at .100 and that might be an advantage to making good torque.

Scat cam going back into storage..........or maybe scrap bin. When I polished the crust off it I revealed chatter marks LOL.
I'd rather have a WEB even if it on chinese iron.

[stan_tichomirov]

What do you guys think of Web 109 compared to these?

Stan
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[Alstrup]

That little bump makes the world of a difference when it comes to valve train control. And yes there are a lot of cams that are aalmost the same.
But yes, the Web cams are nicer in general.

The 109 should be an equivallent to the Engle W125. But, it has less upper rpm power than the 125. It is a nice driver cam in engines in the 2l to 2,2 l area. The 109 can deliver great torque though. In my book the range would be the 109, then the W125 (which is one of the few W cams I like) then the Web 121/125...

[modok]

[modok]

[modok]

Also, it is rare for two cams to be so similar
Here are a few more. The pauter cam is almost two straight lines, it might BE two straght lines and a hand filed transition

The engle you'll note the lash ramp is only .008-.009 tall, but very smooth acceleration. some engle cams should be as quiet as web but you'd need to run zero or negative lash.

[Alstrup]

The little bump that the scat has is what makes the valve train that bit harder to control, but also what helps the cam to make more power.
I honestly do not know enough about it to explain all of it. But maybe I should see if I could find a C45 and put it in the cam analyzer to see what lift coefcient it really has. Sometimes we get surprised.
I definitely wouldnt worry about using 1,25´s on the Web 110.

You are correct about some of the Engle cams being very similar on paper. One of the "silenter" running Engle´s is actually the W125. One of the things I have noticed over the years, and not just with ACVW cams is, that the more precise the cam is the gentler it runs and the more power it delivers.

Elgin wrote an article about this subject not too long ago. I will see if i can find it again.

T

[modok]

I noticed the "bump" is when the lifter is going across the flattest part of the lobe, so it may simply be "push off"....a machining error.
But is the error in the cam or was it in the master? Maybe they are all like that.

I had a reground stock cam marked only "110", decided to check it out.
Worst cam ever! duration at .050 checks 244,245, 246, 265. I checked the screwed up lobe first, and at first I thought it was hydraulic but it would have to be reverse rotation as the opening ramps are gentle and the closing FAST. Never seen anything like it, I think it was loose in the machine when they were grinding it. I threw it away.
Most of these cams are junk.
How hard can they be to make? they only have four lobes LOL

I wonder if the chinese-ground cams are any good? they must have newer machines at least!

[Alstrup]

I dont do it always, but one should actually measure all cams prior to installation due to exactly such issues. Some grinders are worse than others. The problem usually is that they are too busy and let the grinder run too fast. But I have only seen it so bad on one cam which was actually a C25 cam something like 18-20years ago. Sounds like somebody did´nt do a proper job in those days.
I do not know who gets their cams made in China. But if the machines are ok, and the machinist has the patience to let the master run at the correct speed I do not see a problem with it.
T

[bugguy1967]

Torben? Are you ready to provide me some info on the single Otevas yet. I don't care if they have to be shipped over.
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[modok]

good idea, especially if empi discontinues the racing springs.

I had one engle 110 that had one weak intake lobe, and I didn't find it until after running it for months. Lesson learned, and since the they all get degreed.

[SLAKKER]

Anyone have a cam card for the Web 110 cam

[Dan Ruddock]

It is on the webcam site. Click on the grind #

[mark tucker]

the run of the mill acvw cams are the lowest quality grinds I veer seen. like they wont clean the rock or the bearings are dead in the cam grinder.web aint so bad. I havent seen the china cams...I wonder if they are a better quality grind the cb 2250 I put around 130000 miles on looked great at 40000 miles, I assume they have a better shape cam grinding machine than engle.or possiably they just clean it. I stoped ploting the vw cams, inconsistancys...and nothing you can do about it it is what it is.I may of gotten lazy too...just a deburr lobes, visual inspection, check duration& lift,degree it like I want. if you require a quality cam...it aint from the major main stream vw cam companys for the $80-120.