288/280 vs 280/272 cams.

[CrisSilberGrau]

Bad accuracy?

Cams have lift and duration.

You're saying they are ground wrong?

ZiMMie unfortunately he's right. After my ordeal with the post COVID Schricks that failed after break in of about 1,200kms I got a full cat cams set. The intake cam where the vanos vvt socket goes, the one the cam sprockets bolt to, and where the spline shaft enters was of conical shape. Smaller at the mouth and larger at the rear. Off by 0.015 at the mouth and +0.025 at the rear. Dad's a veteran Peng, said that after the hardening process they didn't recheck the cylinder values since the coating inside the cam was consistent with the rest of the piece (ie no machining traces).

Upon contacting catcams they said impossible until I showed them video and pics. They took care of shipping and returned the cam machined, I didn't get a new one as this cam was brand new never used.

I've been running the cat cam setup now for 2000km+ and no issues so far. I've delayed the new injectors and fuel rail to take my time with break in.

Once you open up the engine and deviating from stock you take major risks, financial and emotional.

[Obioban]

So keep the OE head bolts? Wont they stretch with heavy track use?

I blew a head gasket on an s52 years ago from that.

They will not— that is not an issue on the s54.

[SFD87]

No longevity benefit to going off OE head bolts.

So keep the OE head bolts? Wont they stretch with heavy track use?

I blew a head gasket on an s52 years ago from that.

[Obioban]

I saw numerous posts with the 288's but I dont want or need that aggressive of a cam.

Just ordered 280/272's. Ill also be installing ARP head studs in hopes this head gasket lasts me another 15 years

No longevity benefit to going off OE head bolts.

[9kracing]

My personal experience have not been good with them. i spent too much time thinking it could be other issues later to find out its bad cam.
Ive personally witness 3 cars with cat-cams which such a bad "accuracy" that i had to change the maximum adaption targets in for them to work.

Bad accuracy?

Cams have lift and duration.

You're saying they are ground wrong?

[SFD87]

I saw numerous posts with the 288's but I dont want or need that aggressive of a cam.

Just ordered 280/272's. Ill also be installing ARP head studs in hopes this head gasket lasts me another 15 years

[CrisSilberGrau]

Im on page one of this thread and was wondering if there is a dyne that shows the tq curve of these cams.

Also interested in your input on how the 280/272 feel with normal/spirited/track use.

Ill edit this if I get my answers in my research.

Dyno thread has numerous posts with various 288 or 280 setups.

On your point on how they feel, amazing. Dyno tune required for best results. Depending on your mod list you may also have to get higher flowing injectors. A lot is also dependent on the health of your setup too ie. Current compression. With all cams you lose some static compression, that's why the bug money builds include higher compression pistons and any accoutrements that those require.

Just FYI the notion that you don't need followers is now pretty much false. Both Schrick and Cat Cam will not warranty cam damage if you don't buy their full cam kit with followers (and oil bridge, drilled rocker arms for cat cams). I say this because I've been through this with Schrick based on this historical "data" with many members here.

Since COVID the metallurgy for the cam manufacturing process has changed. Followers should be included in this purchase price. If you love the S54 a cammed CSLed one is pretty much top of the food chain type shit.

[SFD87]

I think the 280/272s are a better choice for cars that see any street use.
-Better power below ~7800 rpm
-can reuse stock followers, which makes install much easier (and cheaper)
-smoother idle

I wouldn't be tempted by the 288/280 setup unless I was doing an increase compression ratio and/or stroker and/or high revving (8700+ rpm) build. For a "normal" (full exhaust, CSL intake, etc) bolt on build, 280/272 is the way to go IMO.

Im on page one of this thread and was wondering if there is a dyne that shows the tq curve of these cams.

Also interested in your input on how the 280/272 feel with normal/spirited/track use.

Ill edit this if I get my answers in my research.

[jet_dogg]

Yah man cost is definitely prohibitive sure, but if it means doing things the best possible way then ok. Im trying to gather as much information and also real life experience from sources like this forum. As ever there are differing opinions. My mechanic with loads of experience on Ms only, and building E46 M3 race cars with the parts in question has not used followers and those cars only see race tracks. Other sources close to me that I trust do the same with no issues. So after asking them and why, I'm looking for comparable examples and "how to's" in order to get a clearer picture.

It absolutely makes sense to me get both at the same time, just ... cost.

Lastly I was seriously asking about best practices as it relates to the break in procedure of cams as I was genuinely unaware. DLC install might also considerably add to the install complexity/time. Either way it's a pretty endgame setup for me so looking at all options, best options etc. for me and my use case scenario.

So you've canvassed these opinions from several reputable sources you trust and are now asking the forum in hopes of what? How much advice do you need before you decide what to do?

Don't get them and be done with this agonizing dilemma bro.

[terra]

You went with 288/280 and new followers i assume?

Would someone be able to explain the main reasoning between new followers being recommended for 288s vs 280s?

Has anyone not done followers for 288s and found no issues, conversely what are the issues that arise from not doing them?

I have 288/280s with my original followers and no issues thus far (20k miles on them I think?). I’m sure there’s some extra wear. I’m also pretty sure it won’t amount to a significant amount over the remaining life of the car.

[CrisSilberGrau]

That's the recommendation from the manufacturer whose input I'm more inclined to follow rather than anyone else. The only reason people choose not to install followers is due to cost, that's it.

What metric would one use to quantify "issues"? How would you know if you had an issue? What if you were down on power without realizing it?



I would break in the cams first, what's the hurry?

Yah man cost is definitely prohibitive sure, but if it means doing things the best possible way then ok. Im trying to gather as much information and also real life experience from sources like this forum. As ever there are differing opinions. My mechanic with loads of experience on Ms only, and building E46 M3 race cars with the parts in question has not used followers and those cars only see race tracks. Other sources close to me that I trust do the same with no issues. So after asking them and why, I'm looking for comparable examples and "how to's" in order to get a clearer picture.

It absolutely makes sense to me get both at the same time, just ... cost.

Lastly I was seriously asking about best practices as it relates to the break in procedure of cams as I was genuinely unaware. DLC install might also considerably add to the install complexity/time. Either way it's a pretty endgame setup for me so looking at all options, best options etc. for me and my use case scenario.

[tlow98]

Cams question -

What about slightly used schricks (280/272) (hundred of miles, not thousands) combined with used followers (high mileage but very normal, no major noticeable wear)?

I see many people combining used cams and new followers or vice versa or new cams and followers.

but both used… what says yee? I’m assuming that’s the most risky pairing?

[jet_dogg]

You went with 288/280 and new followers i assume?

Would someone be able to explain the main reasoning between new followers being recommended for 288s vs 280s?

Has anyone not done followers for 288s and found no issues, conversely what are the issues that arise from not doing them?

That's the recommendation from the manufacturer whose input I'm more inclined to follow rather than anyone else. The only reason people choose not to install followers is due to cost, that's it.

What metric would one use to quantify "issues"? How would you know if you had an issue? What if you were down on power without realizing it?

The follow up question is what's best practices when installing new cams? And why?

PS would this practice rule out tuning the car on the dyno right after install?

I would break in the cams first, what's the hurry?

[digger]

I'm not a chemical engineer nor is it my field of expertise.

what i posted is what I've experience on old rocker shaft with new cams. As you can see in the posted picture, it turn out to work great.
i service other s54 "track cars" that used that break in process.
They are on Schricks 288/280 with old rockers. I'll grab pics next time they are in for service.

Funny enough catcams actually suggested that recipe for installing their new cams and rockers with oil bridge.

if you have experience with other minerals oil share it.

no offense but many people just swap cams and go with their normal oil no issue so it doesn't mean much other than you are unlikely to have issues in the first instance. Nevertheless as a means to minimise risk this is what i would do based on the tribology, physics and chemistry, the more aggressive the cam profile the more important as it is less forgiving.

i always recommend new rockers as as it is a risk trying to break-in a worn rocker and new cam its best of the two parts have the roughness as specified by the manufacturer to bed in together

• check / adjust valve clearances
• cam/rockers shall be prelubed with assembly grease from reputable manufacturer
• Use a breakin oil with appropriate ZDDP from same reputable manufacturer to ensure compatibility e.g. Driven
• run engine at approx 2500rpm for 20min immediately on first start up varying rpm a bit to ensure good oil flow and take some load off the cam nose don't let it idle
• drive as per normal and change breakin oil after the recommended mileage interval.
• check valve clearances at the oil change interval (few hundred miles)
• add you're normal oil of choice GTG

[ZiMMie]

Why would you mix and match random oil chemistry it makes zero sense at all. Sorry Using gear oil is nonsense it doesn’t have any real capability to deal with combustion byproducts as it’s not a requirement so will not last/protect long in an engine

Just Buy the correct oil with high pressure additive package suitable for the breakin job.

The s54 is nowhere near as hard on the valve train as what a pushrod v8 with SFT so the recipe for success is well publicised.

The issues with catcams was a production fault if I recall so occurrence of issues is actually still fairly small if the parts are made right.

I'm not a chemical engineer nor is it my field of expertise.

what i posted is what I've experience on old rocker shaft with new cams. As you can see in the posted picture, it turn out to work great.
i service other s54 "track cars" that used that break in process.
They are on Schricks 288/280 with old rockers. I'll grab pics next time they are in for service.

Funny enough catcams actually suggested that recipe for installing their new cams and rockers with oil bridge.

if you have experience with other minerals oil share it.

Here is a close up picture of the lobe wear following that process on old rockers after 35,000km