# 8v Automatic cam gear



## Dumitru (Dec 23, 2002)

I seem to recall something about the existence of a cam gear that automatically advances the timing of the camshaft at low rpm's and retards it at high rpms. Kinda like having a full time gremlin tweaking your Techtonics gear as the engine runs. Does anyone have any pictures of one or know if they are still made?


[Modified by Dumitru, 10:33 PM 1-23-2003]


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## Crash-N-Burn (Jan 17, 2002)

*Re: 8v Automatic cam gear (Dumitru)*

That's pretty cool sounding. Sort of does the same thing as a recurved distributer.


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## mrkrad (Nov 9, 2000)

*Re: 8v Automatic cam gear (Crash-N-Burn)*

find llew on the g60 forum. Or someone had one, very expensive, and no dyno #'s to really back it up. Such a centrifugal device would need cleaning too. price was hefty for sure.


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## ABA Scirocco (May 30, 2001)

*Re: 8v Automatic cam gear (Dumitru)*

Interesting product, I'd love to try one, here's the link http://thorin.adnc.com/~figf


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## Dumitru (Dec 23, 2002)

*Re: 8v Automatic cam gear (ABA Scirocco)*

Bingo, that's the one, thanks.
D


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## kickster (Aug 15, 2000)

*Re: 8v Automatic cam gear (Dumitru)*

no real gain and it stops working after few months. 
this is based on what I was reading in a UK performance book.


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## ABA Scirocco (May 30, 2001)

*Re: 8v Automatic cam gear (kickster)*

I figured there had to be some reason they aren't more well known, cool idea though. In theory, while total horsepower output wouldn't increase, it should broaden the power band if they were 1/2 the price, I'd take a gamble on one.


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## mrkrad (Nov 9, 2000)

*Re: 8v Automatic cam gear (ABA Scirocco)*

where they would be good is in a turbo induction, where you are combatting lag , this is where "no more horsepower" but a large (400-500 maybe) window of in power under the curve could apply.
There's a good reason the new 1.8T's have VVT style, the low end torque gained by changing the intake phase ultimately produces more torque off boost resulting in quicker spoolup.
What might give you a few ft/lbs of torque can make a world of difference in the turbo world. 
So i wouldn't say it sucks, but its a half-ass attempt at doing what many cars (vvt) have done already.


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## Dumitru (Dec 23, 2002)

*Re: 8v Automatic cam gear (ABA Scirocco)*

Unfortunately, for the device to work well it should probably cost more, not less, I find the design a little simplistic. For example there is no protection from the elements. I just may have to roll my own when I get a chance







. And no, it won't improve peak hp but it can expand the powerband. The car should end up being faster in acceleration.


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## ABA Scirocco (May 30, 2001)

*Re: 8v Automatic cam gear (Dumitru)*

If you do roll your own, let me know, maybe I can test it on my buddy's dyno, I'm sure he'd be interested to see the results as well.


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## VWinA (Oct 20, 1999)

*Re: 8v Automatic cam gear (ABA Scirocco)*

Interesting topic, anybody else?


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## antichristonwheels (Jun 14, 2001)

*Re: 8v Automatic cam gear (kickster)*

I bet there is a gain. VW has done the same thing in the 24V VR6 with a different mechanism to change the cam timing with the engine management controlling it.


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## surly (Jun 12, 2002)

*Re: 8v Automatic cam gear (Dumitru)*


_Quote, originally posted by *Dumitru* »_I seem to recall something about the existence of a cam gear that automatically advances the timing of the camshaft at low rpm's and retards it at high rpms...

Its mentioned in this book w/ a dyno test:
http://www.bentleypublishers.c...ct=20
It made small (1-2 hp) but measureable gains.


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## ABA Scirocco (May 30, 2001)

*Re: 8v Automatic cam gear (surly)*


_Quote, originally posted by *surly* »_
Its mentioned in this book w/ a dyno test:
http://www.bentleypublishers.c...ct=20
It made small (1-2 hp) but measureable gains.

Did they by any chance publish a dyno graph? What's of interest to me is not so much the size of the gain but where the gains occur and how they are distributed.


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## VWinA (Oct 20, 1999)

*Re: 8v Automatic cam gear (ABA Scirocco)*


_Quote, originally posted by *ABA Scirocco* »_
Did they by any chance publish a dyno graph? What's of interest to me is not so much the size of the gain but where the gains occur and how they are distributed.

People say there are no hp gains but I dare to disagree. For sure you can dial your car at -3 deg to go on the dyno and it's gona give the same numbers up high as with this variable cam gear but if you can't drive that car then those numbers are pointless. With my car I noticed that I can't give full throttle at until I'm around 3500 rpm because It's a waste. After that the engine is more responsive to my inputs. With this gear, it may be responsive all around.


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## ABA Scirocco (May 30, 2001)

*Re: 8v Automatic cam gear (VWinA)*


_Quote, originally posted by *VWinA* »_
People say there are no hp gains but I dare to disagree. For sure you can dial your car at -3 deg to go on the dyno and it's gona give the same numbers up high as with this variable cam gear but if you can't drive that car then those numbers are pointless. With my car I noticed that I can't give full throttle at until I'm around 3500 rpm because It's a waste. After that the engine is more responsive to my inputs. With this gear, it may be responsive all around.

That's kind of my point, 1 or 2 hp on the top may not be significant but if this gears changes the power band characteristics of the engine, it might still be worth it .


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## mrkrad (Nov 9, 2000)

*Re: 8v Automatic cam gear (ABA Scirocco)*

cause its all about "Torque under the curve" baby.
peak whp is cool and all but i'll take a wide torque band and (hopefully) good gearing to make use of it.


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## surly (Jun 12, 2002)

*Re: 8v Automatic cam gear (ABA Scirocco)*


_Quote, originally posted by *ABA Scirocco* »_
Did they by any chance publish a dyno graph? What's of interest to me is not so much the size of the gain but where the gains occur and how they are distributed.

Yeah, they published a graph. IIRC there were small gains across the curve from maybe 3000 rpm on up.


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## ONLY 8V (Mar 4, 1999)

*Re: 8v Automatic cam gear (Dumitru)*

I have the dyno chart from TT on this...I'll try to dig it up and scan it tonight if I get a chance.


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## mk3Newfie (Oct 17, 2002)

*Re: 8v Automatic cam gear (ONLY 8V)*

anyone have any more input on this???


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## Peter Tong (Jun 17, 1999)

*Re: 8v Automatic cam gear (mk3Newfie)*

Here's a quote of Llew... I'd say these are good results...there are a few others running these last I knew - am checking to see how reliable they've been.
see http://forums.vwvortex.com/zerothread?id=237906
I am currently running the Franco cam gear.
I have the before and after dyno pulls on the wall next to my monitor. Yup I gained no horsepower.
I did however go from 184.2 ft/lbs peak to 204.6 ft/lbs.
Before the cam gear my motor had a torque bulge above 175 ft/lbs from 3400 rpm to 4700 peaking at 184.2 ft/lbs.
After the cam gear the torque bulge above 175 ft/lbs is from 2300 rpm to 5200 rpm peaking at 204.6 ft lbs.
Before the cam gear my motor made 150 ft/lbs from 2500 rpm to 3400 rpm then ramped up above 175 ft at 3500 rpm. Now my graph is above 150 ft/lbs when the dyno starts plotting at 1700 rpm.
I very pleased with it.
Llew.


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## ABA Scirocco (May 30, 2001)

*Re: 8v Automatic cam gear (Peter Tong)*


_Quote, originally posted by *Peter Tong* »_ Yup I gained no horsepower.
I did however go from 184.2 ft/lbs peak to 204.6 ft/lbs.

Right on http://****************.com/smile/emthup.gif that's huge, that must make a noticeable difference in the way the car pulls.


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## Caleb (May 19, 1999)

*Re: 8v Automatic cam gear (ABA Scirocco)*

20 ft/lbs of torque







Thats huge. Was that just with the auto adjust cam gear?


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## rebel_eye (Mar 29, 2001)

*Re: 8v Automatic cam gear (ABA Scirocco)*

perhaps one could modify this device..some one with a little hydralic or electronic expertise !
I was thinking that what if this was to made into some sort of a viscous device. Filled with special fluid that will become more or less viscous when in motion. The liquid would be forced though small orfices and depending on velocity , the liquid would flow or be restricted, advancing or retarding.
Whos in for some R&D


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## TMTuned99.5Golf (Jan 27, 2004)

*Re: 8v Automatic cam gear (rebel_eye)*

think they still sell these anywhere? that website fo rthem seems to not have working links for myself


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## Peter Tong (Jun 17, 1999)

*Re: 8v Automatic cam gear (TMTuned99.5Golf)*

I don't think these have been made in many many years now...


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## jimmy8v (Dec 19, 2004)

*Re: 8v Automatic cam gear (Peter Tong)*

I've got one, althought the engine its going on is not yet built. Those of you with concerns about cleanliness need not worry. Most of the pictures illustrate it without the front plate which protects it very well. Admittedly it would need periodic cleaning though. If anyone is interested i'll try and dig out some pictures. 
It's currently acting as a very rare paperwwight.


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## mrkrad (Nov 9, 2000)

*Re: 8v Automatic cam gear (jimmy8v)*

yeah the gains llew mentioned are because he had a blower cam, and of course forced induction. The high overlap cams reduce the low end torque greatly for high end peak whp. By using this type of device you can reclaim the low end and keep the top end. thats the gist. If you don't have an aggresive overlap cam to scavenge with a positive displacement blower you probably are wasting your time lol.


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## abawp (Nov 30, 2005)

This sounds very similar to Honda's oil pressure adjusted cam gear found on their new (well, not so new anymore) i-VTEC systems. I am sure someone could find a used cam gear from a honda motor, gut the gear, and somehow put it onto an 8v gear. We 8v folks have a positive oil pressure source, just gotta find a way to incorporate into the cam gear.


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## G60Jetta2dr (Feb 11, 2000)

*Re: 8v Automatic cam gear (mrkrad)*


_Quote, originally posted by *mrkrad* »_find llew on the g60 forum. Or someone had one, very expensive, and no dyno #'s to really back it up. Such a centrifugal device would need cleaning too. price was hefty for sure.


Yep I have one. It's really a matter of perspective. My dyno charts before and after running it are actually very different. 
That being said there was no gain in peak power. The cam gear did spread the power band over a wider range. 
All in all I was very happy with the results. I did not have to choose to dial in low end power or high end power. The cam gear gave me both.


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## JGWarner (Oct 22, 2009)

*Re: 8v Automatic cam gear (G60Jetta2dr)*

Wow, this is an old thread man, really diggin deep!








I read about this years ago but never got to see any pics of the device, do you have any G60jetta?


_Modified by JGWarner at 11:15 PM 4-9-2010_


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## antichristonwheels (Jun 14, 2001)

*Re: 8v Automatic cam gear (Dumitru)*

kinda a shame the web page is still up but these are NLA. I bet he could sell a batch if he built some.


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## acadianasportscars (Oct 29, 2008)

I think the fellow is deceased.
I was personally hoping to learn more about it, to design something similar for older Datsuns.


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## ziddey (Apr 16, 2006)

I love this thing


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## Svedka (Jul 4, 2008)

good info and pics in this thread

http://www.mk1dubz.com/forums/showthread.php?t=516


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## Svedka (Jul 4, 2008)

Anyone have any info on this looks like a TT one:laugh:




Dieder said:


> can anyone tell me what i've got here



Franco one


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