This is a very interesting story about the camshafts in general, although i will focus on my Newman R50 camshaft.

After my engine failure, i did some research in my own way, trying to understand a few things. One of those things, are the camshaft specifications. I was very curious about the way my car performed with the Newman camshaft. The specs Newman announces are 264 degrees/8.95mm inlet, and 262 degrees/10.74 exhaust, which seems to be a mild camshaft. (link http://www.newman-cams.com/pdf/bmw.pdf) So i phoned to the best camshaft producer/reprofiler in Greece, named Boubis cams and asked if he could test/measure the cams. The answer was positive This guy is reknowned and acknowledged as the best Greek camshaft specialist for the last 25 years.

The results were very interesting. First, Newman doesn't tell where the durations are taked, 0.1mm lift, 0.5mm lift, 1.0mm lift or 1.25mm (0.050 inch). This guy measured everything in a few minutes with a special tool and software, with acceleration/open/close diagrams, and any spec you can know about a camshaft.

The stock R50/R53 camshaft came out at 244 degrees/8.0mm inlet, and 255/8.5mm exhaust. Very mild, explains why the normally aspirated engine dies at 6k rpm.

Now the interesting part. Newman claims 264/8.95mm In and 262/10.74mm Ex as mentioned above. Well, this is not very true... The examination of the cam showed 274 degrees/10.2mm In and 268 degrees/10.3mm aprox. These numbers are what i remember, i will soon post photos of the sheets i have, showing every possible spec of the cam. After a few months, finally it makes sense why the car showed no fall of power even at 7700rpm (tested only once on the dyno tuning that high), and why the injectors maxed out, something that has never happened on a tuned R50, as far as i know ofcourse and what i read in forums, not many people tune R50s.

Also something more. Valve lift/cam lift=rocker arms ratio. The camshaft max lift is the distance between the higher point of the lobe and the base circle of the cam lobe. The higher the cam lift, the higher the valve lift but not linear as you understand. Schrick and Newman don't use the same rocker arm ratio, Newman uses 1.44:1 for the Inlet, and 1.64 for the exhaust, where Schrick is using the opposite. Where this is coming from? From this :
Newman R53 valve/cam lift --> In 9.43/6.56=1.44, Ex 10.07/6.15=1.64
Schrick R53 valve/cam lift --> In 9.5/5.77=1.64, Ex 9.0/6.24=1.44
And for reference : Kent R50 valve/cam lift --> In 9.5/6.12=1.55, Ex 9.00/5.80=1.55 ..........
BUT! the cam lift, no matter what way you measure and announce the specs, will always be the same! Now it makes sense why Schrick announces 9.0mm valve lift, and Newman announces 10.07mm valve lift, but yet the Schrick will not clear the spark plug tube on the exhaust lobes, and the Newman clears it! Because valve lift announced is directly related to the rocker arm ratio used, but cam lift not. So why the Schrick will not clear the spark plug tubes? Because : Schrick cam lift at exhaust is 6.24mm and Newman cam lift at exhaust is 6.15mm (I am talking for the exhaust lobe as an example because it is the one interfering with the spark plug tube)

I don't know what is the correct ratio, but the specialist i visited used the Schrick rocker arms ratio (i'd trust Schrick more to be honest too), so whatever the correct ratio is, the figures i have are directly comparable, because same rocker arm ratio was used.

 

learn something new everyday

 

Me too! Always wondered about cams. now you've given me more questions!

 

It's better to have more questions, than have none

 

By the way, where are the photos i attached? Guys, can you see them?

 

negative

 

I'm still confused. That was a good write up though.

So do you still have the Newman cam as it came or did you change it?

 

So how much of a difference does a Newman cam make in a R50? My dad has an 06 and is looking for some extra mid-range kick.

 

NickBMW

Nice info. Glad to see someone really went out to get some cams checked out for specs.

 

nick, any news from your mini rebuilding and on cams?

 

Well, not many news, i have already gathered a lot of new parts, among them are a Cosworth CNC head, Cosworth valve springs, larger injectors, a Piper camshaft, an Innovate LC1, now i just need to find the time and cash to assemble them and remap the engine again We'll see what it can make. I am going to upload the specs of the cam soon

 

just some parts

Ok....i'll wait for your specs.
I'm planning to regrind an oem cam...i don't know what i'll obtain.... i'd like to have an everyday car

 

Nick, could you post some pictures of the CNC head so we can see which areas they worked on?

In your original post you spoke of the 2000-6500 RPM advertised cam (PH1 Road cam) but reading through the list of your parts it sounds like you are now possibly targeting a higher RPM range. What useable RPM range is the head targeted for?

If you dyno'd your motor with and without the PH1 cam is there any chance you would share the data? I would be interested to see where the torque peak is with each of the cams.

Thanks

 

they started the business for M7 and all those were reworked cores. The heads that are more expensive (about $3k, I think) were made from thier own castings. The program never really took off in volume, and has been shelved by Cosworth. You can still find the parts in the supply pipeline though. If you want a Cosworth head, buy one now cause there won't be any more.

Anyway, I just read this thread, and NickBMWs post at the top echos what I found when reading thier spec sheet. It's got tons of errors all over the place that make what's already hard to understand totally impossible to understand. But on the other hand, most don't know how to read the numbers, and just end up looking at a quoted RPM range and buy based on that, or what someone else said about a cam, or what thier particular tuner/engine builder likes to use/ or whatever is the flavor of the month.

It's 1.64 intake and 1.44 exhaust, by the way. But even if you use those numbers, I think the Newman page has some lobes reversed.

Another thing to keep in mind is that it's often a practice to populate the spec sheets with cams one COULD make, but not put any money into them until they are ordered. If you hear a really long lead time on a cam you order, it could be this technique in play. It's another marketing game some cam suppliers use to seem like they have more offerings than really exist.

Another couple comments. Advertized durations are usually at 0 or close to it lift, and really are just marketing numbers. Also rocker arm ratios used to quote valve lift are another area. While the Tritec engine has just one set of rocker arm ratios, many a cam grinder will use generic numbers (like Kent, and the 1.75 used on the Crower cam cards for the NS cams). Really, the numbers on web sites are pretty much all less than perfect in some way or another. I went to summit racing to look at some cams there, and they have pretty much everything, but they quote "factory ratios" but don't say what they are. For the tritec, there is only one ratio for intake and one for exhaust. For a Chevy 350, there is more than one factory ratio....

Really, the only way to get really good info is from the cam cards that most ship with the camshaft. This is why FES will be posting copies of the cam cards for the NS1 and NS2 on the FES site.

Matt

 

LOL.. this is an extremely old thread... but!! (lol)

Just to help a few questions that Nick Posed, what 2 years ago??

1) The base circle is why the Schrick hits the spark plug tube and the Newman doesnt !! the Newman exhaust LOBE is under ground. ( standard is 1.181" / Newman is 1.136" -.045 smaller) as you can see by having a smaller base circle, the Lobe lift can be larger, making the lift at the valve higher, and yet STILL miss that Spark plug tube!! Cake! Yes??

2) rocker ratios.. best SWAG is the 1.64 int rr - 1.44 exh rr

3) 100% true there Dr O, advertised duration numbers are just that... advertised for sales!! HOWEVER, if you know what lift the duration numbers are acquired, then you can choose between cams.. ie: 278/289 @ .1mm as the Eu does it. We in the US have found that the LOBE ramps and design can be a LOT different after the .1 mm lift ( .0039") so all our duration numbers ( after the advertised number) is measured at .050" towards the top of the ramp. This will usually be after all the 'trick' and some time guarded ramp angels and accel rates. But it allow a closer actual comparison on camshafts.

Just another thingy... I have a few of the bad AZZ cams from over seas, and in order to get the lift numbers they acquire and to miss the obstructions they all seem to 'under cut' the base circle to allow the numbers to happen Confused yet?? LOL

SOOoooo.... how much of a reduction in the base circle can you do befor the lifters start going nuts on the r50 /r53's?? WELL.... I have found in doing camshaft development for MY car, that .035 to .080" removed on the base will still have NO effects on the BMW lifters. Also IF there is any issues, there are 'wear caps' or 'lash caps' that will make up the difference, and eliminate most, if not all of that distance, allowing the lifters to be back to close to stock position.. MOST Performance camshaft.. do under grind!!

After al this mess is addressed..... then the 'numbers' need to be addressed. or the quality of the cores .LOL Easiest way is to pick your Cam grinder, and then degree the camshaft, or add TRUST!! IF there is NO CAM CARD, with any spec.. I would be suspicious.. yes??

Just me...............................................

Just updating an old thread..

Thumper

 

Thanks for posting the reduced base circle info on the Newman cam. It's somewhat ironic considering how much %$##@ was said about the Crower cams being regrinds.
Two years & the advertised catalog specs still haven't been corrected...The lack of a cam card isn't an issue for me as long as a cam supplier posts accurate checking figures somewhere on their website. I notice the specs for all the non-MINI cams do add up on their website. Not sure why they won't correct their MINI listings.

If there was a detailed primer on selecting cams for the N/A Cooper, more R50 owners might be interested in this mod. The effects of LSA/LCA, what durations & lifts work best in stock & modified heads. What the effects of ground in advance/retard have on a cams performance & how cam timing can be altered to help throttle response on the R50.
There's a lot of cam selection info on the internet, but most of the detailed info is written about big block V8's. Not much that is specific to smaller displacement 4valve N/A motors.

 

LOL.. roger that on the NS cams. I have been gathering and Having cams cut for my own use. Takes a long time for results, as it isnt the performances gained... it is the darn BMW ECU and what IT will accept with out lighting up the cels!!

I have a different Eu. cam that I am testing now, it is amazing that IT is under ground as well. It isnt such a worry there as it 'was' here. and their performance levels are great as well!

So far from degreeing camshafts from the Eu, and running tests in my 06 r53, AFTER you breakdown the way they check their cams ( in MM ) you can get a real close idea. So far , as you said.. the NEWMAN is the only spec sheet that is totally bogus!! Why?? No clue. Newman cam also grind for a vendor here in the US. Maybe THAT is the reason??

Just me..........................

Thumper

PS: Camshafts for the r50/r53 - Piper/ Cat/ Newman/ Mynes/ NS/1320-Cat/Schrick/ Kent .. to name a few. There are a few high lift cams under development, as well as some more aggressive track grinds.... time will see.
Tpr

 

Ok so would this cause an issue where the car won't start at all? I have a NS1 and the car refuses to start. Turns over and all but no fire