ALH upgrades maybe ALH/BHW??? advice

[PickleRick]

One night on an empty highway i was cruising about 65 mph which was what i considered my top safe comforable speed. I was passed by a blue hard top 40 going at least 80mph. The speed wasn't so much the issue as was what would happen if I needed to slow down for an obstical immediately at that speed. You can ram it or roll it, not much else.

90 mph....i don't miss street tuning at all.

 

[fjdiesel]

Going 60mph on a relatively flat road boost was 3.4-4.9psi. With some inclines it would climb to 6.8.

I put my foot in it in third just to see boost. Not beating on it, but rodding on it, it got up to 22 and some change.

This morning I had 23 degrees f intake temps. Just in case that makes a difference.

Thanks @TDIMeister for the timing link. Great video!!

Got the timing checked. It is right on!

 

[TDIMeister]

I can't take credit for that, it was Mozambiquer.

The boost levels at cruise are not unusual for a stock-bodied TDI... Yours could certainly stand for a bit more without increasing the fueling, it will certainly reduce your EGTs.

One way you can quickly and easily do this is - if you don't already have a 3 bar MAP sensor or tune for it - to install one directly in place of the stock 2.5 bar sensor without remapping. This will effectively increase the requested absolute pressure by 3/2.5 or 20%. so, 4 PSI gauge will be (14.5+5)*1.2=22.2 PSI (absolute), which equals 7.7 PSI (gauge, at sea level).

Be very careful though - 22 PSI originally requested by the ECU mapping at full boost would become 29.3 PSI!

As for the mileage, I think it's in the ballpark of where it's supposed to be given the tires and aerodynamics of your particular vehicle. Swapping in a BHW bottom end will not really help you in this regard.

PS: I don't condone swapping in a 3 bar MAP sensor without re-mapping, even this is exactly what I have been doing for the past 6 years on my own car. Try this at your own risk. The proper action, once you have determined that the EGT responds desirably to more boost as suggested, is to have the ECU remapped.

 

[fjdiesel]

I will double check. But I think it is a 3 bar map. If it is then if I reach out to malone they can figure that into the tune easily it sounds??

 

[TDIMeister]

Yes, that's right.

 

[fjdiesel]

Thanks. I will check that out.

 

[TDIMeister]

Some further thoughts. Increasing the requested boost will also tend to make the turbo vane position more closed, which could increase exhaust manifold pressure) and negatively impact fuel consumption a bit. It's not that the OP's current 2.5" is inadequate, but I generally favour the most free-flowing exhaust as possible (none of this BS about turbo engines needing some backpressure), and if you're not constrained by packaging in a total custom build, I am all for go-big-or-go-home. The OP should hook up a pressure gauge to the EGR port and measure it, preferably if you have a 2-needle gauge that can simultaneously display EMP and boost at the same time and see their relationship. I have been a big proponent of the GTD1752VRK turbo, and the people who have taken this endorsement in their builds have had nothing but raves about it. Maybe something for the OP to think about.

Based on the gearing and tire size, I'm getting 1900 RPM at 60 MPH. If this is correct, it's pretty much optimal strictly from a fuel economy point of view based on the BSFC map:

Without knowing the actual curb weight and precise Cd*A of the vehicle, I should nevertheless expect that you could improve slightly on the 22-25 MPG you're getting now, but a lot also hangs many other variables in the build and on driving style... EMP@boost@load@RPM would tell me a lot.

 

[fjdiesel]

I do have a 3 bar map sensor.

I will check to see if I have a gauge i can check EMP. What kind of readings would it be? Just so I can determine if I have one that will work.

When you say load, do you mean throttle position?

I imagine I should have some of this information before I contact Malone to increase boost.. or decide to change turbos..

I will get curb weight today to see if it has changed from the 3800# when i first got it drivable.

Thank you.

 

[fjdiesel]

The curb weight was 3900# with me in it.

 

[PickleRick]

The 40 is heavy for a swb vehicle. It's like a jeep but all grown up

 

[fjdiesel]

During the build process I thought I would get it down to around 3k. Softtop instead of the hard top, aluminum tub, newer seats, 4 cyl with aluminum head(compared to the straight 6) I thought the motor was gonna shave a ton off the end. I was shocked the first time I weighed it. Was kinda surprised it wasn't more yesterday. Apparently haven't added much more. Lol. It is a hoot to drive with the tdi!!

 

[PickleRick]

I was thinking they were a little over 4k with the 2f.

When I took the 1f out of my 40 and put in the v8 I had to remove the 4 inch lift leaf springs off the front and install 2.5 inch springs as it sat way too high in the front. When i tossed out the v8 and put in the diesel I had to go back to the 4 inch front springs.

The F was stupid heavy.