1.6TD in Caddy

[dieselherb1]

Okay I finally got the Quantum TD into the caddy. I own 5 TDI cars, this is my first 1.6TD with a T3 turbo.
First thing I noticed was the engine has to rev higher to get any boost(compared to the TDI 96-98) They pull from 1500-1800 on up. And you have to keep your foot into the throttle to keep the boost. It has the OEM POV valve. Would it help much to block it of or disable it. Its more fun to drive than the N/A caddy but more work than the TDIs. I have 3 TDI engines(1 ALH,2 1Z) that I plan to put in other caddies. Problably sell this one(it will be too slow)

[vanbcguy]

The T3 is wayyyy bigger than the turbo you're used to on the '96-'98 TDI - therefore it takes a lot more exhaust pressure to spool it up.  The T3 / K24 are the biggest turbos VW ever used on any of these engines.  Yeah, generally you'll start seeing boost around 1800 RPM and actually have the turbo spooled by 2200 RPM or so, that's pretty normal for this combination.

The "tiny" K03 turbo on those TDI's has the advantage that it will spool way faster, but from a performance perspective it's pretty much topped out at factory pressures (9-10 PSI)  The T3 / K24 can be cranked up in to the 20's though and still live quite happily.  You'll find some people on here who've gone higher than that, but the "my engine / turbo blew up" stories start appearing quite a lot after you pass 30 PSI.

The factory BOV opens at about 12 PSI, so if you're still running stock boost it isn't a factor.  If you do plan on turning your boost up at all then you'll need to worry about disabling it, but it won't make your turbo spool any faster.

If you've got a spare K03 off a TDI you can run that on your 1.6 and get faster spooling!

[rallydiesel]

Toss a vnt15 on that caddy and you'll have the low end response of you tdi's with the top end pull of the t3.

[dieselherb1]

I have a VNT turbo but its on a ALH engine to be installed in a Caddy. How do you think the T3 would respond on a 1Z engine with elec. or mech. pump?

[rallydiesel]

I think the t3 is a better match to the 1.9 than the 1.6.

[vanbcguy]

I think the t3 is a better match to the 1.9 than the 1.6.

I'd definitely tend to agree - I really don't know why VW ran such big turbos on the 1.6.  Why run a turbo that takes forever to spool but can put out big boost numbers when factory settings were so low?  The extra displacement of the 1.9 would more than likely help get things going sooner though.

[8v-of-fury]

I really don't know why VW ran such big turbos on the 1.6.  Why run a turbo that takes forever to spool but can put out big boost numbers when factory settings were so low? 

For when us guys started to mod them 20 years later lol

[vanbcguy]

Yeah, that's about all I can think of...  Either that or they got worried the diesel would perform TOO well and hurt their gasoline engine sales...

In all honesty it wouldn't surprise me if the challenge was more around finding a turbo that small back in the '70s as I don't believe there were all that many small displacement low RPM turbo engines around at the time.  Big stuff, sure, but anything as tiny as a 1.6?

But back to the original poster - yeah, if you've got a VNT then give that a shot, there's quite a few people around here running one with great results!