Who Has cat cams 3652's??? I need your help!!!!URGENT

[20vturbo]

Here is the story
I have the billet steel cams that have the adjustable chain gears..I got them from Bob QED..They are installed as per Bob's specs
However I have reason to believe that my timing is off
1 rough idle
2 4inHg of vacuum at idle
3 compression test gives 150psi on all 4 cylinders

what I believe is that even though the cams are installed as per Bob's instructions, the chain gears are misaligned

I need to know
How rough is your idle and how much vacuum you read
I need pictures of the marks and some of the cam lobes at tdc please please
please

I think the timing between the 2 cams is off and not top to bottom..This will cause the cams to overlap regardless to crank and top alignment

[dirtybrd]

16 links from mark to mark, it doesn't matter what cam it is.

[20vturbo]

16 links from mark to mark, it doesn't matter what cam it is.

Yes I have 16 links and it does matter If the gear is turned on the cam then the whole cam is off, wich I believe it is

[20vturbo]

16 links from mark to mark, it doesn't matter what cam it is.

You have 3652? the billet steel ones with the adjustable chain gears?

[dougyfresh]

16 links from mark to mark, it doesn't matter what cam it is.

but that's TDC on the cams. Gotta make sure the cams are marked.


Did bob mark the cams for you? He marks the back of the cams with a paint marker.


put your OEM cams in and see if idle and vacuum changes. its easy. know how many times i've swapped cams this year? too many.

[O2VW1.8T]

I had the 3652's my engine vacuum was at 5 or less, compression was in the 160's, kinda rough idle. These are big cams for the stock ecu. I had the cast versions. But the power was nice. I rev'd to 9200rpm daily

[20vturbo]

I had the 3652's my engine vacuum was at 5 or less, compresson was in the 160's, kinda rough idle. These are big cams for the stock ecu. I had the cast versions

Yes I have the same, I have the same rough idle and 5 or 4 vacuum..I spoke to comobody else that has them and they idle about 10 vacuum

[20vturbo]

but that's TDC on the cams. Gotta make sure the cams are marked.


Did bob mark the cams for you? He marks the back of the cams with a paint marker.


put your OEM cams in and see if idle and vacuum changes. its easy. know how many times i've swapped cams this year? too many.

Dude I went crazy today...The cam tensioner still makes some noise, oil pressure is there, I don't know why that mother****** is noisy and is brand new from ecs tuning....Then this timing shit, I must've advanced and retarded the timing gear like 20 times

I am thinking of getting a shorter chain and run the cams with no tensioner just like the 16v

[20vturbo]

but that's TDC on the cams. Gotta make sure the cams are marked.


Did bob mark the cams for you? He marks the back of the cams with a paint marker.


put your OEM cams in and see if idle and vacuum changes. its easy. know how many times i've swapped cams this year? too many.

This is a picture I got from Bob..My cams are identical to these ones

[dougyfresh]

are they timed right? ie: are the cam gears pressed onto the cams correctly? bob pins them. the paint mark should be inline with the keyway of those cam gears. my 3651s are like that.


see the keyway? see the pin that bob puts in?

[20vturbo]

are they timed right? ie: are the cam gears pressed onto the cams correctly? bob pins them. the paint mark should be inline with the keyway of those cam gears. my 3651s are like that.


see the keyway? see the pin that bob puts in?

Well Guess what My cams are different..I have the billet steel ones wich have adjustable chain gears held in place with 6 little alen screws on each cam...Bob told me that he adjusted them when i bought them, now I don't know but...Today I spoke to Eurodyne and their car idles 10inHg vacuum with the same cams

[Don Supreme]

Well Guess what My cams are different..I have the billet steel ones wich have adjustable chain gears held in place with 6 little alen screws on each cam...Bob told me that he adjusted them when i bought them, now I don't know but...Today I spoke to Eurodyne and their car idles 10inHg vacuum with the same cams

eurodyne may have tuned for the cams though...

i.e. More timing and higher idle ****- Those adjustment can have an impact on the idle vac.

[20vturbo]

eurodyne may have tuned for the cams though...

i.e. More timing and higher idle ****- Those adjustment can have an impact on the idle vac.

I am not sure I was told their car also has a bit of a shake on idle but they see more vacuum..I will ask tomorrow if they tuned it for the cams..I know that they run the oem ecu

I think I need to make a tool kinda of like the one they use for the 2.7 to lock both banks, and lock the 2 cams together then adjust the gears and after that I may be good to go

[O2VW1.8T]

Yes I have the same, I have the same rough idle and 5 or 4 vacuum..I spoke to comobody else that has them and they idle about 10 vacuum

10 maybe on standalone or a oem ecu that is custom tuned. I ran the eurodyne 1000cc software.

[dougyfresh]

Well Guess what My cams are different..I have the billet steel ones wich have adjustable chain gears held in place with 6 little alen screws on each cam...Bob told me that he adjusted them when i bought them, now I don't know but...Today I spoke to Eurodyne and their car idles 10inHg vacuum with the same cams

oh... yeah. can't help you there.

[20vturbo]

who else has the 3652's?????

[20vturbo]

I saw this gti on youtube running the 52 and he had about 10inhg, he had an autronic standalone though

[mike-2ptzero]

Have to expect a rough idle and very low vacuum with such a larger cam on our cars, you might want to have the idle rpm raised.

[20vturbo]

Have to expect a rough idle and very low vacuum with such a larger cam on our cars, you might want to have the idle rpm raised.

I am trying to make sure that my cams are installed correct..So far one person other than me had them and they were doing the same
Wich cams do you have??

[20vturbo]

I had the 3652's my engine vacuum was at 5 or less, compression was in the 160's, kinda rough idle. These are big cams for the stock ecu. I had the cast versions. But the power was nice. I rev'd to 9200rpm daily

Wich bov did you have? I have to change the spring in my tial 50mm..Did you tweak you bov with those cams?

[mike-2ptzero]

I am trying to make sure that my cams are installed correct..So far one person other than me had them and they were doing the same
Wich cams do you have??

I still run Schrick cams but might jump to the 52's, wouldnt be as much of an issue for me since I run a stand alone and my idle rpm sits at 2k+ seeing that I only use the car at the drag strip.

[mike-2ptzero]

Wich bov did you have? I have to change the spring in my tial 50mm..Did you tweak you bov with those cams?

what spring do you have in yours and why do you feel like you need to change it?

[20vturbo]

what spring do you have in yours? Because even when my vacuum was at 10 with my old 8:1(120-125psi) CR my Tial 50 was never open at idle.

I dunno, whatever spring it comes from tial...We tested it and it starts to open around 20 to 22 inhg...I think I got mine from 034..It has to stay open on idle correct?

[20vturbo]

I have the 11 psi as per tial...With the vacuum that I see even the weakest spring will be too strong

[O2VW1.8T]

Wich bov did you have? I have to change the spring in my tial 50mm..Did you tweak you bov with those cams?

tial 50mm with the 11psi spring i believe. I was going to change the spring but never got around to it.

[20vturbo]

tial 50mm with the 11psi spring i believe. I was going to change the spring but never got around to it.

DID you remove them? why?

[dirtybrd]

I dunno, whatever spring it comes from tial...We tested it and it starts to open around 20 to 22 inhg...I think I got mine from 034..It has to stay open on idle correct?

No, you only want it to open when venting.

[mike-2ptzero]

I dunno, whatever spring it comes from tial...We tested it and it starts to open around 20 to 22 inhg...I think I got mine from 034..It has to stay open on idle correct?

You want it closed at idle because there is always pressure in the IC pipe even at idle. You only need to change the spring if you want the valve to open sooner during shifting or if your engine doesnt make enough vacuum to open the valve causing compressor surge during shifting or let off the throttle quickly.

[dirtybrd]

IIRC the spring is there only to keep it form opening at idle? It won't open under boost due to pressure being equal in both sides, plus the spring pressure, am I right Mike?

[mike-2ptzero]

IIRC the spring is there only to keep it form opening at idle? It won't open under boost due to pressure being equal in both sides, plus the spring pressure, am I right Mike?

Correct. The spring sets how much vacuum is needed to open it and to offset any pressure drop when keeping it closed. They sell different rate springs so the valve can be opened at different vacuum levels to fine tune it to how much vacuum the engine produces when he does shift gears. If the engine doesn't produce enough vacuum to open the valve with the spring it has then he wants to go with a softer spring.

[dirtybrd]

I need to do some tuning on mine, or limit the release amount.

[Don Supreme]

Whats your idle speed? Try and bump it 100 RPM with lemmiwinks.

[mike-2ptzero]

I need to do some tuning on mine, or limit the release amount.

Just make sure you dont increase the spring rate too much or you will end up with some compressor surge. If you are getting some delay when you shift into the next gear you can also try limiting how much pressure is let out of the valve, I did this by putting a normal worm clamp around the vent area of the valve. After I did that the huge delay I had going into 2nd gear was no longer there. The valve just lets way to much air out when it opens, I think a few other A4 owners running the Tial ended up doing the same thing to decrease how much air was released when they ran into the same issue.

Changing the spring will just make the valve open later but wont decrease how much it opens or how much air is released.


Here is a picture of my tial, you might be able to see the clamp.

[dirtybrd]

I saw that a long time ago, but have yet to do it. I have a OBX BOV which is a really good knock off of the Tial, it comes with an 11psi spring. Yes, I get alot of lag between gears

[mike-2ptzero]

I saw that a long time ago, but have yet to do it. I have a OBX BOV which is a really good knock off of the Tial, it comes with an 11psi spring. Yes, I get alot of lag between gears

Try the clamp first before changing the spring since a clamp is pretty cheap.

[dirtybrd]

When she runs again.

[20vturbo]

Well I spoke to eurodyne again this morning and they didn't tune the idle..I am sure there is something wrong with the timing between the 2 cams due to the chain gears
So other cars see 10inhg vacuum at idle with the same cams
I spoke with Mike Unitronic and he's reaching some of his customers that use the same cams to verify it

when I drove the car the valve opened too late so yes I did get some surge very brief after wich the valve opened...

[AudiA4Turbo22]

so what cams are ideal for a 2.0L setup that spins to 8.5k?

[AudiA4_20T]

it depends what you want, I think you should do the 53s.

To the OP, I have these cams with a Tapp tune, Ill let you know how it goes

[dirtybrd]

Stef, you haven't even broken the motor in yet. Give it some time.

so what cams are ideal for a 2.0L setup that spins to 8.5k?

I run the 58's.