intake cam shaft

[Dunkdafunk]

Hi, does anyone know if you can buy a performance inlet cam shaft which has a bigger hpfp lobe?

[Dan_FR]

CDL is marginally bigger, otherwise you uprate the pump

[pudding]

Yeah, I believe the CDL cam has half a mill more lift than the BYD cam but I'm not sure how much more lift both have over an AXX/BWA.

If the CDL has a different duration and lift profile as well as more HPFP lift, you'll be needing a remap....and I wouldn't just fit the inlet cam.  Fit both.

I can't imagine the CDL has wild cam profiles vs AXX due to emissions regulations, but worth investigating.  Not a lot of info about it though, especially on the lift/duration/overlap differences.

[rich83]

IIRC if you change the inlet cam from BYD to CDL it does need a different map.

[pudding]

Yeah I would expect the HPFP duty to need pulling back. As we all know, half a mill shaved off a follower from wear has a profound effect on fuelling!

I'm keen to know if the intake valve profile is different though.  Could be a good upgrade if there's more lift and duration. More beans from the same amount of boost.

It kind of supports what I've said before about OEMs approach to adding more power.  It's a lot more than simply turning the boost up!  Look what the CDL got for 'just' 60 more hp than the AXX.  Stronger block, harder cylinder head, different cams, bigger turbo, bigger intercooler.....all of it!  VW know their sh*t 

Although standard CDLs make nearer 280hp in reality 

[Dunkdafunk]

Ok so i can fit a CDL intake, but i would need a map? Im going to make an assumption that the performanc hpfp just have a stronger and larger floating piston? Thats what you change when you look at the internals? Im just thinking the CDL cam and map would skip the cost of a hpfp. Also, can a mk5 gti shell take a CDL engine?

[colesey]

I don’t imagine you would have to remap after fitting a CDL cam, just like you don’t have to after fitting an upgraded hpfp piston and many still feel gains in the midrange with the extra fuelling available. Remapping to lift the pressure requested to 130 bar does however unlock the full potential of the fuelling.

Going to all the hassle of fitting a CDL cam instead of spending £200 on VIS pump internals sounds a bit extreme though.

[rich83]

I don’t imagine you would have to remap after fitting a CDL cam, just like you don’t have to after fitting an upgraded hpfp piston and many still feel gains in the midrange with the extra fuelling available. Remapping to lift the pressure requested to 130 bar does however unlock the full potential of the fuelling.

Going to all the hassle of fitting a CDL cam instead of spending £200 on VIS pump internals sounds a bit extreme though.

Its the lobes on the actual camshaft that are different on the CDL one. Im racking my brain from years ago but I am sure that if you put a CDL intake cam in a BYD or BWA then it needs mapping to run correctly.

[colesey]

Ah, I see. i had thought the cam timing was the same with the only difference being the higher lift on the hpfp lobe.

[rich83]

I dont think so.... although I am happy to be wrong. v

[Dan_FR]

The CDL cam is not a replacement for an uprated pump - not even close

Get a pump, forget the CDL cam.

[pudding]

Agreed.

IMO a CDL should be fitted in it's entirety, not just bits of it.  A complete waste of a time otherwise. Yep, a CDL will drop straight into a MK5, as would any MK6/MK7 EA888 engine, which is another option people can explore to replace tired original engines.

[Dunkdafunk]

Thanks. I have to replace the camshaft anyway, so it seemed like the more viable option if the pump lobe was bigger. I get that its a different engine. But it cant be that different to not gain benifits from it surely?  I think in my situation where i need to change the cams anyway, id be lookin at changing the exhaust and inlet myself, but from what you guys say the cdl cams is a waste of time as a direct replacement for a tuned hpfp. Ok. Be interesting to see the differences in profles.

[pudding]

Honestly, I would just fit a BWA/AXX, which ever one you have, intake cam and be done with it.  Fitting a CDL cam will open a can of worms, and not cheap worms.

The cam phasing map is probably different on the CDL, as well as the pump lift, and likely the lift and duration.  You can't slap it in and not need a remap unfortunately.

Yes aftermarket HPFPs have more fuel volume because the piston area is larger, but they still work off the factory lift. When you add more lift AND volume, things get dicey.  Yes the excess fuel is drained off, and/or injector duty cycle trimmed to suit against lambda, but there are limits to what the standard map can self adjust to.

Plus a well respected tuner (R Tech) have confirmed a remap would be required.  They tune these engines daily, so have more insight than most of us.

[Dunkdafunk]

Cheers. Il fit a bwa intake. Take out the engine. Then sell it and drop in a cdl lol
I can see it needing a remap. The valve lift margins would be way out of trim. Cheers for your help pudding