# sds on 1.8t head with VVT question



## evildub82 (Sep 14, 2002)

im in the process of trying to build a 2.0 20v using the 2.0 aba bottom end and the new 1.8t 20v head. im planning on using full sds engine management and was concerned about the variable valve timing, which im not even sure which heads have it or if its even called VVT, the search only got me more confused but gave me some good general knowlage. i was wondering if you could give me an idea of what to do or expect and which code head to use. the car is in no way going to be emmisions legal so is there a way to get rid of it? or will it be to my benefit on such a high boost application?
my intentions are to build a high boost 20v with approx. 420whp or more while trying to keep it simple leaving out all these rediculous emissions and engine control options. im hoping, hehe key word, to rely on pure ingenuity.
please help. the vortex knows all!!!


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## mrkrad (Nov 9, 2000)

*Re: sds on 1.8t head with VVT question (evildub82)*

the vvt is designed to bring more torque down load, thus spooling faster. it's not as complex, as say dual-vanos.
You could use a rpm switch to kick it in down low and that would probably help a teeny bit in the off boost dept.


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## VDUBBINDizzy (Jul 23, 2001)

*Re: sds on 1.8t head with VVT question (evildub82)*

Well in transverse motors, it's only for emissions purposes. It's on AWW and AWP heads. AWD heads don't have it.


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## nscirocco (Oct 4, 2000)

*Re: sds on 1.8t head with VVT question (evildub82)*

double check if the head bolts on to the block first.. they use different size head bolts 11mm vs 10mm ..
if it does, without machining, let us know.


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## evildub82 (Sep 14, 2002)

*Re: sds on 1.8t head with VVT question (nscirocco)*

well from what ive read the head bolts on the newer heads are 10mm and the older ones are 11mm. im hoping to grab an older head, then i shouldnt have to worry about machining anything, or about this valve timing thing if it applies.
ive read that sometimes the vvt kicks in at higher rpms as well? not sure though, i was thinknig about an rpm switch but what rpm to set it on and off? if i mapped out where the stock vvt kicks in i could work my way from there, but then again i have no clue what incriment adjustments are needed. i guess i could look at chipped ecu maps and determan it from there







. and as for it going on more then once durring an entire rpm sweep that means i need multiple rpm switches...that just sounds like a pain to me.










[Modified by evildub82, 6:36 PM 3-5-2003]


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## VDUBBINDizzy (Jul 23, 2001)

*Re: sds on 1.8t head with VVT question (evildub82)*

It's variable cam timing so it's either on or off.


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## evildub82 (Sep 14, 2002)

*Re: sds on 1.8t head with VVT question (VDUBBINDizzy)*

hmm...if its either on or off and i dont hook it up its off then. is there anyway that it might accidently slip since there is some sort of solenoid controlling it? im still unsure if will benifit me or not either. i might have to play the good old trial and error game. not sure. 
more info pleaseeeee


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## VDUBBINDizzy (Jul 23, 2001)

*Re: sds on 1.8t head with VVT question (evildub82)*

One cam (not sure which) is chain driven. The other is driven off a belt on the first cam. The solenoid just applies tension to this belt.


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## evildub82 (Sep 14, 2002)

*Re: sds on 1.8t head with VVT question (VDUBBINDizzy)*

i thought that the intake cam was chain driven off the exhaust cam (belt driven by timing belt) just like on the 16v head. so where are these other belts involved. i just saw a picture of the head with a removed valve cover and looks the same as the 16v head but with a with a pulley in between the cams and chain, is this what keeps it tight? check out the picture.
if so can it be removed and the chain shortend or should i just leave it and dont wire anything up.


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## evildub82 (Sep 14, 2002)

*Re: sds on 1.8t head with VVT question (evildub82)*

anyone out there running SDS on their 1.8t and encounter the same problem? or am i just making a situation out of nothing?
i just read a searched thread by killa and it helped alot but still not sure if it will help performance. i guess i can hardwire it and dyno the car with it on and off and see what happends, maybe there will be a optimum time for it on and off, then ill use and rpm switch.


[Modified by evildub82, 12:58 AM 3-6-2003]


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## VDUBBINDizzy (Jul 23, 2001)

*Re: sds on 1.8t head with VVT question (evildub82)*

http://forums.vwvortex.com/zerothread?id=569755 
Some good reading a little past half way down.


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