Author Topic: Cam shaft info - gasser cams for upgrade on TDI's. (Read 7765 times)

lbreton · « **on:** May 25, 2008, 06:07:12 pm »

I don't think you guys want to missing copying this info onto your computers. Cam shaft info - gasser cams for upgrade on TDI's...mods required.

http://forums.tdiclub.com/showthread.php?p=2104237#post2104237

RabbitGTDguy · « **Reply #1 on:** May 25, 2008, 08:38:44 pm »

Digging into TDIClub even further...you'll find the original cam research as referenced in the thread regarding an 8v gasser "G" grind cam that was used in tdi rs's car....and worked quite well. It did require shaving/machining in the head to allow the lobes to clear as well as some machining to the valve pockets if I remember correctly.
He mentioned is gains as "good" without the sacrifice of a lot of low end...did extend the motor to be able to breath better up high....
had a rough/odd/high idle if I remember correct.

So...what I am saying (other than that database of cams)...there is an even better thread on this very discussion there! It'll be interesting to see how that discussion continues...as it was quite interesting the last time it came around.

Joe

gigaz2 · « **Reply #2 on:** May 26, 2008, 01:06:52 am »

just a note as this is more than discussed already:

Wouldn't a cam upgrade make more sense on a IDI? I mean, a cam usually makes the torque go up in the rev range, and TDI's have a much lower limit.

RabbitGTDguy · « **Reply #3 on:** May 26, 2008, 07:14:51 am »

The upgrading of a cam on the TDI is possible. Most notably...the cam from a AAZ (still looking for one) will work well and then you have the cams that Dave has through PP. The look of the curve has shown that usually you usually push the meat of the power band up higher in the RPM range at the sacrifice of some low end torque...

Yes, it has been brought up and discussed here pretty well too. I think on either engine...IDI or TDI (IDI could use it more) you just have to be comfortable with the sacrifice in the process (low end torque) for the gains later on. Now, I'd question the cost of performance cam vs. pure performance of....def.
However, if an OEM cam could work in place...that'd be great.

Additionally, I thought more about TDI RS's original posts and my discussions with him a few years back on TDIClub. The G grind cam was just simply able to be used on its own too. I believe he had to have it modified as well. I need to go back and look. I think I archived our PM's to each other.

Joe

jimfoo · « **Reply #4 on:** May 26, 2008, 07:23:20 am »

What is the difference between a TDI and AAZ cam? I had been looking for that info but couldn't find anything. I guess luckily my TDI was an AAZ, so that's what cam it got. I have a spare cam, but it got some lobe damage to 1 lobe when my lifter broke.

RabbitGTDguy · « **Reply #5 on:** May 26, 2008, 08:45:45 am »

don't quote me on this...i would need to dig a bit more to find the info on the AAZ vs. TDI (1z/AHU/ALH) cam, the improvements were slight...somewhere between the stock cam and what a PP cam would net you.
....but I believe the g grid that TDI RS used had to be reground for as little overlap as possible...somewhere around 16degress... it worked well for him....but as I said, requires machining in the head and the cam.

Generic search yields a lot more info into the topic...

G grind....performance cam info...
http://forums.tdiclub.com/showthread.php?t=72745&highlight=G-grind

TDIMeister post on cams...
http://forums.tdiclub.com/showthread.php?t=108233&page=1

Here is more TDI camshaft improvement info...
A comparison thread... (PP cams info)
http://forums.tdiclub.com/showthread.php?t=209763&highlight=AAZ+cam

Decent performance camshaft discussion...err...ok...
http://forums.tdiclub.com/showthread.php?t=209766&highlight=Camshaft+upgrade

Stock Cam dimensions
http://forums.tdiclub.com/showthread.php?t=209208&highlight=AAZ+cam

thats enough for now...more where that cam from.

Joe

shortysclimbin · « **Reply #6 on:** June 22, 2008, 04:11:18 pm »

I have a few more pics to post but have them up on my tdi engine build. So far from what I have found the oem mk3 2.0l cam may not be that bad of a cam for the tdi engine. I will say that the 260/260 tt cam might be a little better but really requires some piston clearance and regrinding to get it to a more neutral (no overlap) camshaft. As far as the paper details I think the technical info that tdi rs has left out is on the issues with mounting a gas cam in a tdi engine. A custom adapter will need to be made and a new timing lock will need to be grooved into the cam. I am working right now on coming up with an adapter and might have it for sale after all things are tested and worked through for the mk3 camshaft.

As far as overlap and issues with it. Does anyone know what the "limit" is with diesel engines and at what point do you drastically loose lower end power?

bluemotion · « **Reply #7 on:** July 01, 2008, 08:29:24 pm »

Why not go the other way with the camshaft and tune the TDI for more performance at lower RPM's in an effort to increase mpg's? How often do you really drive a TDI over 4000RPM with all the way the gearing is set up? TDI's have plenty of power...

hatemi · « **Reply #8 on:** July 01, 2008, 10:41:17 pm »

The reason for the search of more usable range up high is the fact that to make the power at a lower RPM mans more torque. And after a point it gets useles since it just spins the wheels no matter what. Trust me on this. I know :twisted: 450nm is about the max under 3.5k. Then after 4k it could have more and still keep the grip.

gigaz2 · « **Reply #9 on:** July 07, 2008, 08:04:19 am »

I got hold of a "D" grind gasser cam, it is slightly milder than the "G" cam that everyone talks about.

I can't find any info on how to modify the pulley for it to fit on my 1.6TD project, can someone help?

EDIT:
I don't have a gasser pulley, so I can't compare them directly, and the stock gasser aren't adjustable like the diesel ones

shortysclimbin · « **Reply #10 on:** July 07, 2008, 08:29:19 pm »

I should have a few addapters made up soon dont know costs yet if you are interested in one.. you could take the cams specs in an aba head...

gigaz2 · « **Reply #11 on:** July 08, 2008, 05:25:20 am »

048 109 101D:

lobe center: 113.5º
lift:0.400"
duration @1mm:I217/E215

I guess I can buy an adjustable vernier pulley for a 8v gasser and it should work, but I think the width of the pulley is bigger on diesel, am I right?

lord_verminaard · « **Reply #12 on:** July 09, 2008, 11:02:40 am »

Quote from: "gigaz2"

I guess I can buy an adjustable vernier pulley for a 8v gasser and it should work, but I think the width of the pulley is bigger on diesel, am I right?

You are correct. I'm not sure that would work out too well.

Brendan

gigaz2 · « **Reply #13 on:** July 09, 2008, 11:29:54 am »

thanks, so I would have to buy both pulleys and make an adjustable one myself... gasser center section and the outside from a diesel one.

guess I'll wait for those adapters, cam goes into the "interesting but currently worthless parts" shelve