Newbie 1.6 TD looking for 135 hp or better - page 1 - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• Newbie 1.6 TD looking for 135 hp or better by rodpaslow on 21 Aug, 2009 09:31
• I have a 90 diesel golf and just bought a 92 TD engine and have plans to rebuild it and put it in that car.  I also plan on having performance diesel do their thing to the IP. 
  
  I've been reading the form a lot, and have a few questions about power and turbo issue.  I have a 92 jetta with a gas 16V and I'd like to get comparable power out of the 1.6 TD.  Will the current turbo do it?  Also, going with larger exhaust, in order to get good hp & boost, does the downpipe need significant changes?  If you go to a 2.5" exhaust or so, isn't the turbo outlet (downpipe) going to be the largest restriction that will need to be replaced with something larger?
  
  Any other changes needed for about 140 hp out of this 1.6 td?
• #1 by Rabbit on Roids on 21 Aug, 2009 12:52
• open up all your exhaust, from the turbine to the rear bumper. the bigger the better. we dont need back pressure, thats why we have turbos. turn up your fuel, do the gov mod, add as big of an intercooler as you can fit, and make the turbo suck as cold of air as you can make it suck. and add a boost controller or just save yourself the effort and bolt a VNT on there, they are friggen awesome. oh yea, boost gauges and pyro gauges are your best friend on a diesel with power.
• #2 by rodpaslow on 21 Aug, 2009 13:09
• Not to sound too stupid, but I'm assuming a VNT is a variable vane turbo - they have vanes that move to improve airflow to the impeller - is this correct?
  
  Thanks!
• #3 by Rabbit on Roids on 21 Aug, 2009 13:11
• yea, and they are just like having a compound turbo setup. boost right off the line clear up to the upper rpm limit.
• #4 by rodpaslow on 21 Aug, 2009 13:58
• One more question and that will be it till I am about to install it - what size of vnt will bolt right up to the exhaust manifold; or is there one that will?  If not will a 1.9 manifold work with one? I'm just hoping I don't have to fab up a exhaust manifold to work with one.
  
  Thanks Again.
• #5 by sawedoffgolf on 22 Aug, 2009 04:30
• Quote from: rodpaslow on 21 Aug, 2009 13:58

  One more question and that will be it till I am about to install it - what size of vnt will bolt right up to the exhaust manifold; or is there one that will?  If not will a 1.9 manifold work with one? I'm just hoping I don't have to fab up a exhaust manifold to work with one.
  
  Thanks Again.
  

  
  No need to make a exhaust manifold, VNT's have them built in.
  
• #6 by Rabbit on Roids on 22 Aug, 2009 10:00
• ^ ^ ^ thats part of the reason VNT's are the sh*t, they are self contained. and ready to bolt on for the most part. you have to fab feed and return lines, but thats no big deal. you WILL build 135 or more with a VNT on there. and a vnt15 or 17 will work just fine. add an intercooler in there too. they respond super well to them.
• #7 by sawedoffgolf on 22 Aug, 2009 19:17
• Quote from: Rabbit on Roids on 22 Aug, 2009 10:00

  ^ ^ ^ thats part of the reason VNT's are the sh*t, they are self contained. and ready to bolt on for the most part. you have to fab feed and return lines, but thats no big deal. you WILL build 135 or more with a VNT on there. and a vnt15 or 17 will work just fine. add an intercooler in there too. they respond super well to them.
  

  
  word, my buddys mk1 jetta TD with vnt15 and TMIC setup, gov mod and gtd nozzles blows the doors off all mk4's. boost straight off the line is addicting.
• #8 by hamradio on 23 Aug, 2009 07:15
• I'm going to venture to say that if you did make 135hp on a VNT15, it would not last very long.
  
  
  My car is sure as hell not making anywhere near 135hp, and I'm running about 22 psi, unintercooled, vnt15.  Part of the issue is the vane control.  With my mechanical control system, to achieve the fast spool times I want, the car is making about 12 psi cruising down the freeway.  Listening to the wooshing noise gets very old on a 2 hour drive down the freeway. 
• #9 by Rabbit on Roids on 23 Aug, 2009 08:36
• 135 off a VNT will kill it? whatever...
  i am FOR 100% POSITIVE my car has over 135 horse with a GT17 VNT.
  and i dont know why all you trip out about hooking up the vanes? i hooked them up one day, then un hooked them the next day. boost was too sporadic with the vanes hooked up. it takes till about 2200 or so before the boost really comes on, but then it comes on like a big ol hit. i have abused my turbo from the day i put it on, thought for sure i was gonna spin that turbo in half, but it still works beautifully. i bet i could get more power out of a VNT if it had good bearings and seals. but mine does not. no one gives these turbos the respect they deserve. these are the cream of the crop in my eyes.
  
  and i wouldnt run over 15psi without an intercooler. i did, and all it does is heat the air excessively. intercoolers are the best improvement on these engines it seems like. my car absolutely came alive when i IC'd it. i bet i gained 25 horsepower, but i turned the boost up when i did it. funny part is, everyone on here told me i was gonna blow my IC apart at anything over 15psi, but guess what? its seen 25 psi quite a few times sustained.
• #10 by MJF on 23 Aug, 2009 13:13
• VNT15 is tiny 90/110hp tdi-turbo. 135hp from idi will need more. Gt1749v´s are different story, there is several different versions. From 1,9 110hp tdi to 2,0 170hp pd. (v, va, vb etc). Most vnt´s have not "built in" exhaust manifolds.
• #11 by Rabbit on Roids on 23 Aug, 2009 13:58
• ok, well sorry. the 15's and 17's have the manis built in. they are really the only vnts that come from volkswagens arent they? and my turbo is a 1749vb on my rabbit. thats supposed to be one of the better vnt17's arent they? i was under the assumption that the vnt15 and the VNT GT1749xx turbos were pretty much the same unit..
• #12 by MJF on 23 Aug, 2009 14:41
• 1749vb is one of the biggest 1749´s, from 150hp pd. At least vnt15, 1749v and va, does not have built in manifold, dunno others small vnt´s. I count Passats and Transporters as Volkswagens too, so there is others   But yes, those are the 1,9 vnt´s.
• #13 by lord_verminaard on 24 Aug, 2009 07:39
• VNT15's are junk, pure and simple.  They work ok for stock 90hp TDI but anything over that is bad news.  I probably saw 15-20 TDI's with blown turbos when I worked for VW, about half of them were stuck vanes, the other half were snapped shafts.  VW should have put the much better vnt17 on the ALH engines as stock.  As the 1.6 is smaller displacement, you need to run a higher pressure ratio to get the same amount of performance, the VNT15 in stock form on a 1.9 was already on the edge of it's PR limit.
  
  Brendan
• #14 by rodpaslow on 24 Aug, 2009 09:12
• Hey, thanks..sounds like I should be looking for a VNT17.