Joe's collection of Westfalia bits

[vanbcguy]

Only thing to be aware of with an old school or big truck focused pyrometer is the reaction speed. Larger thermocouples take a longer time to react. For that reason most folks around here tend to go for the smallest probe possible as it will react the fastest (less mass takes less time to heat up).

The Aircraft Spruce micro thermocouple is a popular choice.

Sent from my HTC One X using Tapatalk 2

[JoeCanuck]

Greetings....Now that the longest winter since the last ice age finally seems to be coming to a close, it's time to put away the shovel and get out the wrenches. 

I've been going through some threads to try and refresh my brain.  I forgot how much stuff there is but it's slowly starting to sink back in.

I will probably be going with the K14 turbo, for a balance between quick spool and flow.  This winter, I picked up a jetta TDI intercooler which will fit nicely in the external air intake tray in the corner...but I'm still mulling over fabbing a WAIC.  I'll see how well the Jetta IC works out.  I think I will end up with a short intake run which will help with turbo lag.

I'm planning on going for 20-22(ish) peak boost with the ability to run 15psi all day.  I have a digital pyro and a boost guage for engine protection and I'll be running oil temp as well as oil pressure, amps, volts and water temp. 

After much searching, I really haven't been able to find a good answer to a few questions; how much boost can the stock head gasket and bolts take?  Are there issues with checking the torque on head and bottom end bolts?  What kind of power can I expect with the governor mod, playing with the boost needle/star wheel, smoke screw and turbo wastegate?

[Gizmoman]

Welcome back from the cold!
You may want to reconsider K-14. I'm replacing mine currently with a Holset HE200 from Alcaid (not running yet).
I believe the K-14 just couldn't produce enough air to run with the Giles settings of my IP, but there may have been other factors I won't go into here. Whatever the reason ends up being, I'm hoping to keep EGTs below 1150

Still, the K-14 can do up to 18 psi from what I've read and mostly thin, hot air after that.

[JoeCanuck]

It's good to come in from hibernation.  Is the k14 unable to keep up with the ETG's of your westy?

EDIT;  What I worry about is that the stock pump I'm running wouldn't provide enough fuel to spool up a k24 at low enough revs to make it really driveable.  I'm looking for as much low end torque I can get and not really looking for top end hp. 

I'm guessing that your setup will produce significantly more power than I'm after at the moment.  That Giles pump probably won't have much trouble spooling up a bigger turbo. 

I'm willing to err on the small side for now since I do have the K24 kicking around if the k14 isn't up to snuff. 

It's good to have extra bits.

[Gizmoman]

It's good to come in from hibernation.  Is the k14 unable to keep up with the ETG's of your westy?

EDIT;  What I worry about is that the stock pump I'm running wouldn't provide enough fuel to spool up a k24 at low enough revs to make it really driveable.  I'm looking for as much low end torque I can get and not really looking for top end hp. 

I'm guessing that your setup will produce significantly more power than I'm after at the moment.  That Giles pump probably won't have much trouble spooling up a bigger turbo. 

I'm willing to err on the small side for now since I do have the K24 kicking around if the k14 isn't up to snuff. 

It's good to have extra bits.

The K-14 is very reliable - just not at 20 psi.
I'ts enough to get the brick moving well enough till you add more poop with the pump

[JoeCanuck]

Well tonight I spent a bunch of google time trying to figure out the voodoo of compressor mapping.  I stumbled upon a few sites which helped.  Using the information  linked to below, I calculated that a K14 on a 1.9l engine will be 70% efficient pushing 20psi at 5000rpm...and according to the hondaswap tutorial, anything over 70% is good.  The K14 in this application can produce 20psi boost starting at around 2200rpm.  According to my calculations, even 25 psi below about 4800rpm is still above 60% efficiency.

In contrast, the K24 can't produce 20psi until around 2500rpm....but it can stay over 70% efficiency at 30psi until 5200rpm.

Now one should take all this with a grain of salt....this is my first crack at playing with compressor maps and I haven't done anything resembling math for decades.  Ideally, someone smarter with more time on their hands would work out compressor efficiencies for the more popular turbos....perhaps supplying some real data to one of the most frequently asked questions.

I may post this info in the general section....after I get some beer and sleep....math makes my head hurt.

This site gives a really good tutorial to understanding compressor maps

http://hondaswap.com/threads/compressor-map-reading-for-dummies.129194/

Here is a big collection of compressor maps
  
http://www.not2fast.com/turbo/maps/all.html#kkk

This one is a compressor map flow calculator...(It seems the VE, (efficiency), is typically 85% for 2 valve engines and 90% for 4 valve engines)

http://lovehorsepower.com/joomla/index.php?option=com_content&view=article&id=35:compressor-flow-map-calculator&catid=8:mr2-helpful-stuff&Itemid=49

This is a handy unit converter, because some of the maps are in kg/sec and/or m3/sec.

http://www.convertunits.com/from/lb/min/to/.04+kg/s

[theman53]

There are a ton of different K14. Our vw have 2 that I know of for the diesels. The aaz k14 and the 1.6 eco K14 and the eco's k14 is smaller than the aaz one. I think you did a good job at reading the maps, but in our case I think the K14 is a restriction a little above 3,000 rpm.

cool find on the compressor maps.

[Gizmoman]

Joe, Here is a shot of my K-14 tag. Don't know what the numbers mean. My engine is an AAZ 1.9 but that's no guarantee the turbo is (I believe the engine came out of a forklift ).


I didn't have an EGT sensor with the stock pump (pre-Giles) so I can't say what temps it was hitting. I was running 15 lbs (which is 5 lbs over stock) on a long 6% grade and smeared #4 piston against the bore and stuck the rings good. As you will have a sensor, there's no need to worry, just not sure it will get you where you want to be.
It's a good turbo for early boost no doubt.

Tough choices with these heavy vehicles. My goal is to daily drive it so I want quick spool around town and getting on the freeway. The long-term plan is to also do lots of long distance travelling as well and we like the mountains. Getting up them at 65-70 MPH when it's 110 ambient is gong to require lots of fairly dense (cool) air and more fuel than the stock pump can deliver.

In the end, just taking it easy in the slow lane would have been a much cheaper alternative

[Gizmoman]

All said, I would do the K24 set to 20-22 psi and turn up the fuel screw if it bolted up without too much effort.
The 300 RPM spool difference isn't much for the gain in flow.

[JoeCanuck]

One thing I learned while driving trucks....especially the old, mechanical pumped ones...is that rpm's are your friend if egt's  start climbing. That usually means downshifting..  Lugging can get egt's way up there.
  
Generally, if you're not blowing black, you're probably ok....but a pyro is always a good idea.

It's going to be trial and error for me.  I haven't even driven this thing yet so I don't really know what I'll end up with.  I'm not ruling anything our yet....and no decision is final.  I reckon I'll start with the k14 and if that's not enough, I'll drop in the k24.....but I still have time to change my mind a time or three.   i can really see how a variable vane turbo would be the ultimate way to go.

Gizmoman....you may just be right.  I have no doubt that the k24 can pump a ton more air than the K14.  My playing around with the maps made that loud and clear.