Sdi Cam...

You must be careful when rolling an engine over by hand checking for interference between valves and pistons. When sitting, hydraulic cam followers bleed down to a lower dimension than when running. Roll over by hand, seems ok. Start up and cam followers pump up and then contact may occur. I'm not suggesting this is the problem, just a note to those changing cams.

One trick I've used is to set the engine at TDC, then rotate cam by hand (pulley on, belt off, cam lock out) and see how far I can rotate in each direction before I feel valve to piston contact. Gives you an idea of how much room it actually there. Of course if followers have bled down, this changes things.

-Eric

Rub87 said:

Can't see why a TDI would not idle with a sdi cam if timing etc is set well..

Click to expand...

I can't understand it but is real... my IP is locked, my camshaft and crankshaft too and tensioner is in the correct position... I've set my IQ at 5.0 and my timing before the cam change was 65... I don't know what's happen...but an AGP SDI camshaft doesn't work well with stock ECU...

Ski in NC said:

You must be careful when rolling an engine over by hand checking for interference between valves and pistons. When sitting, hydraulic cam followers bleed down to a lower dimension than when running. Roll over by hand, seems ok. Start up and cam followers pump up and then contact may occur. I'm not suggesting this is the problem, just a note to those changing cams.

One trick I've used is to set the engine at TDC, then rotate cam by hand (pulley on, belt off, cam lock out) and see how far I can rotate in each direction before I feel valve to piston contact. Gives you an idea of how much room it actually there. Of course if followers have bled down, this changes things.

-Eric

Click to expand...

All must to be OK, i've install my AFN cam this morning and the cam followers works well and i can hear the compression sound when turn the engine by hand...

Rub87 said:

Can't see why a TDI would not idle with a sdi cam if timing etc is set well..

Click to expand...

I can't understand it but it's real... my IP is locked, my camshaft and crankshaft too and tensioner is in the correct position...can it be an IQ problem? I have my IQ at 5.0 and my timing before the cam change was 65... can the timing change for to use a different cam? I don't know what's happen...but an AGP SDI camshaft doesn't work well with stock TDI ECU...

THANKS TO ALL FOR YOUR HELP

don't see the influence of the ecu, especially on idle..

I'd recheck the cam timing again. Any chance the locking slot differs somehow to the original?

I installed my AFN cam this afternoon and all is OK... i'm not doubt about sdi cam doesn't work well...

How old was that cam was it for mechanical lifters

mojogoes said:

How old was that cam was it for mechanical lifters

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the cam is from AGP engine,1.9 SDi 68hps of year 2000... i don't understand your second question...

No its ok that motor/agp also uses hydrolic lifters.

The locking slot is different (wider) in 038 style engines.. maybe you have put car out of spec somehow? god knows

Rub87 said:

The locking slot is different (wider) in 038 style engines.. maybe you have put car out of spec somehow? god knows

Click to expand...

In that case it would be very easy to be out of tdc 1mm = x amount of degree's means alot.

Rub87 said:

The locking slot is different (wider) in 038 style engines.. maybe you have put car out of spec somehow? god knows

Click to expand...

I didn't felt that... seems to be the same slot...
I did the work well, i'm sure of that. All the parts was at TDC,and the flywheel mark was exactly where had stay...

I putted the locking tool in the cam and turned it until one side of the locking tool was touching the head... in the other side of the locking tool i measured the distance beetween it and the head... i turned the cam for to have the same distance in the two sides of the locking tool to head and i putted metal precision pieces with the same measurements in each sides of the locking tool,beetween it and head... the cam was in the correct position, no doubts...

Is possible that is it a Injection quantity problem or a lobes duration/lift...no compatible with stock TDI maps? my timing before change them was 65... is possible that with different cam timing changes?

Your cam locking toolshould be flush with the head. it should touch the head on both sides! Its actually so tight that you need to wiggle it to make it go in there. If you use the right tool then you can put it in only one way. It was propably WAY off timing!

hatemi said:

Your cam locking toolshould be flush with the head. it should touch the head on both sides! Its actually so tight that you need to wiggle it to make it go in there. If you use the right tool then you can put it in only one way. It was propably WAY off timing!

Click to expand...

No,no,no... my tool was bought from Metalnerd tools and has a very little space beetween it and head in both sides,that is solutioned with metal precission rules... i did my afn cam with that tool and car runs great now! isn't a bad install problem!

Satiro said:

No,no,no... my tool was bought from Metalnerd tools and has a very little space beetween it and head in both sides,that is solutioned with metal precission rules... i did my afn cam with that tool and car runs great now! isn't a bad install problem!

Click to expand...

So its because its just wrong for the tdi or the cam could have had a lot of wear............but i reckon the first reason more so.

If the cam was timed right then your pump was off by a tooth. No way a SDI cam could cause those symptoms alone. The difference between that and TDI cam is just too damn small. Even smaler.

hatemi said:

If the cam was timed right then your pump was off by a tooth. No way a SDI cam could cause those symptoms alone. The difference between that and TDI cam is just too damn small. Even smaler.

Click to expand...

Nooooooooo! mi IP was blocking with tool... i checked the belt tension and was correct... all was in their place...
the SDI lobes are different than TDI , no necessary to measure them for to know it, it's evident with a simple looking...

AGAIN: can be a excessive IQ problem for those larger duration lobes? i have Race520 and my IQ is around 4.5-5.0...
shudder seemed than when change the IQ value with vagcom to a excessive lower value...but worse.

hatemi said:

If the cam was timed right then your pump was off by a tooth. No way a SDI cam could cause those symptoms alone. The difference between that and TDI cam is just too damn small. Even smaler.

Click to expand...

This is true but i don't want to be BAD by implying Satiro couldn't wrench!! .only joking Satiro.....lol.

Yes you may be correct that the iq needed to be dialed inn possibly mapped as your r520's pop off later giving retarded injection timing.

mojogoes said:

This is true but i don't want to be BAD by implying Satiro couldn't wrench!! .only joking Satiro.....lol.

Yes you may be correct that the iq needed to be dialed inn possibly mapped as your r520's pop off later giving retarded injection timing.

Click to expand...

I used the same method for to reinstall my afn cam(both cams has the same lock slot) and my car runs now than rocket,no delay in the throtle pedal response, beautiful engine sound at idle,stronger... when things be where they must be, engine feels happy...and i'm:

if somebody wants to try this SDI cam i will send it to you for 0€..only shipping costs...

Satiro said:

if somebody wants to try this SDI cam i will send it to you for 0€..only shipping costs...

Click to expand...

send it to me,we have a dyno day on oct 25th,if the cam runs,i'll get a couple pulls on it.if it doesn't,well you know what will happen,on the shelf it sits.
chill and i will get to the bottom of this.

Satiro said:

I used the same method for to reinstall my afn cam(both cams has the same lock slot) and my car runs now than rocket,no delay in the throtle pedal response, beautiful engine sound at idle,stronger... when things be where they must be, engine feels happy...and i'm:

if somebody wants to try this SDI cam i will send it to you for 0€..only shipping costs...

Click to expand...

Thats great now the valve are opening and closing at the right time.........lol i'm just thinking of the time that my timing was out = crank from sooo muc play on the crank pulley......the backfiring was unreal!

did anyone else ever install an sdi cam and get good results? Any photos showing lobe comparison?

I know someone have tried the sdi cam. the cam shift the torq point lower in the rpm band.
a bit more turbo-spool in low rpm. lower hp in higher rpm.

The SDI cam differs from the TDI primarily by reduced negative overlap and earlier exhaust opening. One can already predict that with the same intake valve closure timing and lower intake centreline angle that it's going to favour the lower RPM range. With an earlier exhaust valve opening, it's also easy to predict that there will be more exhaust gas energy to spool the turbocharger at the cost of a small amount of expansion work in the piston. This cam could be beneficial in some odd engine state of tune where you need to spool a big (ancient?) turbo yet operate mostly at low engine speeds and, where the turbo matching is such that you are certain of a positive pressure delta from intake to exhaust during the overlap period, otherwise the the cam is working against you in all respects.

What would REALLY make a difference is if one could adapt an A3 or A4 8V gasser cam, as listed in my table at the top of the thread. It is not plug-and-play by any means, but somebody with access to a junk-yard and some fabrication/improvising ability can try such a thing with vast numbers of these engines sitting in yards and the cams could almost be obtained for a song. I have it on perfect authority that these cam profiles are not all that different than aftermarket TDI cams for which people pay $$$/€€€/£££ for and if one can get it to work in a TDI will perform comparably to one.

TDIMeister said:

What would REALLY make a difference is if one could adapt an A3 or A4 8V gasser cam, as listed in my table at the top of the thread. It is not plug-and-play by any means, but somebody with access to a junk-yard and some fabrication/improvising ability can try such a thing with vast numbers of these engines sitting in yards and the cams could almost be obtained for a song. I have it on perfect authority that these cam profiles are not all that different than aftermarket TDI cams for which people pay $$$/€€€/£££ for and if one can get it to work in a TDI will perform comparably to one.

Click to expand...

Sounds really interesting! what mods are necessary for to fit one of those cams?

It was discussed a bit here. The nose on the sprocket-end is different between the gasoline and TDI cam. You'll need to figure out your own way to get it to work. There's also probably no slot on the free-end so you also need some way to clock the camshaft right to have the right timing. The Diesel sprocket itself is wider but same number of teeth and diameter.

TDIMeister said:

What would REALLY make a difference is if one could adapt an A3 or A4 8V gasser cam, as listed in my table at the top of the thread. It is not plug-and-play by any means, but somebody with access to a junk-yard and some fabrication/improvising ability can try such a thing with vast numbers of these engines sitting in yards and the cams could almost be obtained for a song. I have it on perfect authority that these cam profiles are not all that different than aftermarket TDI cams for which people pay $$$/€€€/£££ for and if one can get it to work in a TDI will perform comparably to one.

Click to expand...

Very interesting you bring this up. I have always wondered how a mk3 ABA 2.0l cam would run in a TDI. I actually have one sitting there waiting for me to try it.

Looking back at that thread i had wrote how i wanted to put one in my 1.6 IDI but blew her up before that happend. lol

TDIMeister said:

The SDI cam differs from the TDI primarily by reduced negative overlap and earlier exhaust opening. One can already predict that with the same intake valve closure timing and lower intake centreline angle that it's going to favour the lower RPM range. With an earlier exhaust valve opening, it's also easy to predict that there will be more exhaust gas energy to spool the turbocharger at the cost of a small amount of expansion work in the piston. This cam could be beneficial in some odd engine state of tune where you need to spool a big (ancient?) turbo yet operate mostly at low engine speeds and, where the turbo matching is such that you are certain of a positive pressure delta from intake to exhaust during the overlap period, otherwise the the cam is working against you in all respects.

Click to expand...

ok so how can you explain this: http://forum.octaviaclub.pl/files/na_waku_sdi_139.jpg ? the improvement isn't huge but it's clearly visible the dyno was done before and after fitting the SDI cam without any remap adjustments the guy says that he can feel the difference and it's only positive

Hi bios83bog,

When you say a nice upgrade, you noticed more power in the low/mid/high rpm?
I have an AFN and would be keen to do an oem-type upgrade if there are benefits....
What was the condition of your AFN cam? worn at all? Is the SDi higher lift?

Hi, you can compare the cam's specs on the topic's 1st page: AEY vs AFN, the lift is the same only the intake/exhaust duration is different. I have a demo soft now and after installing the sdi cam I have to do the logs for the tuner to make the final version.
I only noticed that my old tdi revs like a gasser... i'll keep you informed after the final version of the soft.
My AFN camshaft is like new..and I have on the clock almost 292 000 km .