Installing camshafts on CR TDI

A little video of my cam install.

Go easy on me, I'm a rookie.

https://youtu.be/5WpD85s4fDY

Nice, solid content. Interesting to see they've made cast cam blanks mimicking the tube and lobe VW cams

I am curious if these are better compared to my dbilas camshafts.

Will have a pretty much stand alone test of before and after dyno.

The only things changed are cams, stiffer valve springs and ARP head studs.

I'll post the before and after numbers.

Cool. Can't wait to see how much power the cams and springs add. Great video!

Curious myself With some fuel and more boost you should pass 300.

in the for the # difference

Lobe profile is different from mine , colt is much rounder at the tip.

Finally got the rig put back together. Had some serious lifter tick for about 60 miles of easy but varied rpm driving.

Here is a video clip of shortly after first start:

https://youtu.be/_sE7x6asf1Y

Was starting to get nervous something was put together wrong, but then the last start, perfect.

The exhaust note is noticably lower and more grumbly. Sounds mean. Took a couple stabs up above 4,500 rpm. Seems to be real happy up on top end.

Now to get some logging done and tune tweeks. Dyno appointment is for Tuesday, but I don't think I'll be ready by then.

More to come.

travis45 said:

Finally got the rig put back together. Had some serious lifter tick for about 60 miles of easy but varied rpm driving.
...
Was starting to get nervous something was put together wrong, but then the last start, perfect.

Click to expand...

yeah, you've usually got to give her a taste of the rev limiter to pump up collapsed lifters in a quick manner, otherwise they take quite a while to come up.

Go for it! Curious what you get this time. Would be nice to compare with the old tune to see what camshafts alone bring.

Bad news kids. Warmed up to pull some logs. Was really running nicely. The first stab at WOT and there was a pop at 4,370rpm, engine quit.

Pulled over and first check was the timing belt, all perfect there. No oil spraying anywhere. First flabed ride home.

Poped the injector covers and stuck the borescope in there and several rockers we're off on the intake side.

Pretty bummed out. Not sure what the cause of failure was. Will have to pull the valve cover off and review the carnage.

Oh crap. Feel really bad for you bud. But it might not be that terrible. Hopefully the bolts just worked loose and nothing got hurt too bad.

Which bolts? The cam girdle? Didn't appear to be the case. The rockers aren't bolted to anything

We had looked into the manufacture of an upgrade cast cam for the CR, before the DieselGate fiasco. Our decision was with so many vehicles around, and years of the problem 'cam rings', it would be a good replacement. But with so many to be crushed and no continued run, we nixed it until the dust settled. I think it has not only settled, but there are other, bigger issues.

Probably the single factor that stops us, is not the cam itself, but the rest of the components, which cannot handle the pressure or lift. There is also a geometry issue that we felt caused a limit for height, mostly because the rockers themselves were too weak. The only thing causing the valves to rotate is a small and weak contact on the rocker. The rocker is an inherently weak design, without a good way to bolster it.

We got more confirmation when we received a cylinder head by way of one of the 'aggressive builders' on the Club, a CBEA head, that was sent to a customer of ours. It was claimed to have only 6,000 km on it. Every valve on the exhaust side had stopped rotating and had a hammered flat spot on the valve stem, every rocker was flattened, and every roller was not turning, because of the flattened needles inside the roller. I don't know what horsepower was intended, but I believe it might have been an attempt above 250hp.

At that point, our interest in developing power for the CR faded completely away.

My though is you would have knocked the rockers off of the exhaust side cam.

Frank, you sent me an email a year and a half or two years ago saying the same thing.

Very good chance in this case I put something together wrong as it was my first time inside a head.

Darkside has built CR's north of 400hp and some others are close to that, so I know it can be done.

Hate to jump to conclusions before taking a look at it more thoroughly.

travis45 said:

Which bolts? The cam girdle? Didn't appear to be the case. The rockers aren't bolted to anything

Click to expand...

I guess I was thinking the cam journal caps might have loosened up. I don't want to get your hopes up, but if the rockers aren't mangled, sometimes they'll just pop back on and be ok. A good long warm up period before revving out the engine can help keep oil pressure from rocketing too high- which can cause rockers to pop off.

I rans also some reground cams I think made by colt cams. The performance was good but didnt work without making pockets in pistons. Learned the hard way, intake valve dropped after few k km.

If someone wants them, still gathering dust.

Frank, on that car you say lifter rolled seized you are sure the springs didnt bind? I run upgraded spring in mine for 30k with approx 300hp. Works just fine. Stock cams.

Ruben, what engine were you running said Colt Cams in?

oval port w piezo inj. no that it matters afaik.

Ruben, so you have the same common rail head design with the same roller rockers?

I need to open it up and take a look again. Looks like there is at least one exhaust valve that lost a rocker.

All cr use same rockers including v6. Could be that the EA288 is different but I dont think you one of these.

Are you sure the valves also didnt kiss a piston and this made it get stuck or damaged a rocker?

This car has stock rockers, I dont even swap them for new, never dropped one in all the time we have ran these engines hard:

https://www.youtube.com/watch?v=s-g1x4m6YhE&list=PLz_nHs7o9ueXUmnewp0YVAtfLPo_dxHKs

This one does too:

https://www.youtube.com/watch?v=2ODijZUayKI

Both see over 5000rpm continuous, the Arosa might have 100 dyno pulls before a meeting where it does 40 1/4 mile drag runs.

The rockers are the same in almost all the CR engines, if we find a weakness we will improve but so far nothing to report.

Thanks for your comments Ryan and Ruben. That helps to rule the poor design out. My investigation is ongoing. Got the valve cover off last night and confirmed that I lost a total of 8 rockers in one simultaneous event. Some intake and some exhaust.

This leads me to believe that one of two things happened. One, I installed something incorrectly, or two, the grind duration on the cams are just too great and that at high RPM there is enough deflection to cause an impact.

Before I take it apart I plan to clean the bits out of the head best I can, rotate to TDC, double check my timing belt that it is still perfect. The tensioner is pointing right where it needs to be right now and I was able to rotate the engine multiple times and lock at TDC and pin the cam sprocket. Then verify that the cams are set properly before I take them out to rule out an installation mistake.

Any other ideas of how to investigate properly? Is there a way to check the pistons for witness marks without pulling the head?

Thanks,
Travis

Then maybe cam timing off? With stage 3 cam maybe too much lift to be off just a little?

travis45 said:

Thanks for your comments Ryan and Ruben. That helps to rule the poor design out. My investigation is ongoing. Got the valve cover off last night and confirmed that I lost a total of 8 rockers in one simultaneous event. Some intake and some exhaust.

This leads me to believe that one of two things happened. One, I installed something incorrectly, or two, the grind duration on the cams are just too great and that at high RPM there is enough deflection to cause an impact.

Before I take it apart I plan to clean the bits out of the head best I can, rotate to TDC, double check my timing belt that it is still perfect. The tensioner is pointing right where it needs to be right now and I was able to rotate the engine multiple times and lock at TDC and pin the cam sprocket. Then verify that the cams are set properly before I take them out to rule out an installation mistake.

Any other ideas of how to investigate properly? Is there a way to check the pistons for witness marks without pulling the head?

Thanks,
Travis

Click to expand...

what valve springs did you run? could it be the valves where floating quite a bit and this made them lose contact with the rockers?



pulling heads seems cheap insurance. I had an intake valve drop at 4000 rpm and this cost u a head and 4 pistons and maybe a block if u run out of luck.

I installed stiffer valve springs with the cam install. 80% more seat strength. Although I didn't want to have to pull the head, I know you are right that the right thing to do is to take it off for a full inspection.

how big is the injector bore? there are $10 inspection cameras on ebay that are 7mm OD with decent resolution

also take and put air pressure to each cylinder at its TDC to check the valves for anomalies, just listening in the ports with a section of vacuum hose stuffed in your ear as a stethoscope to see about one or two being louder

I have a cheap borescope but it won't fit through the tight spot where the nozzle is. I'm going to pull the head for a full inspection. Guess I may as well do some porting while it's out.

Running Dbilas + custom made springs for 8000km with 300 hard pulls 0-200+ km/h and not an issue.

I think your camshaft is the problem.