300TDi Boost Pin + Boost Ring + VNT Turbo = Bad?

[andrewMcF]

So I've been rebuilding a 300TDi, my first engine build... And as all 300TDi guys do they add the boost ring and pin from Fourby to the injector pump, I have this on my other 300TDI's as well. Love them. But since I was feeling extra generous I purchased a Hybrid Billet Performance Turbo from Fourby... I was wondering if all three together might be too much? This engine will also be running with a Allisport uprated double core intercooler...

The reason I ask is in this video this guy recommends against doing all three together as it's too much for the engine....


he says that adding a boost pin, boost ring, and a vnt turbo, "you will blow your motor."

Now i'm not sure what to think...

Thoughts?

Thanks,
Andrew

[red90]

The parts really mean nothing on their own. You need to adjust them so that the fueling rate and resulting EGTs are safe. That is the critical thing. None of these items make it any less safe than can be set with the stock system

1) In my testing, the boost ring does nothing useful. Your mileage may vary. I'm a fairly careful and methodical tester but I only tried it on one engine.

2) The boost pin is misunderstood. What it allows is a larger RANGE of boost fueling compensation. This is only required if you are running more than 20 psi boost. Below that, the stock pin has enough range. The pin does not affect in any way the maximum amount of fueling. This is set by the pump's plunger size.

3) The VNT lowers the start of boost by around 300 rpm and allow higher peak boost. It is a lot of money for not much difference for the average person. It is a bit more efficient.

4) If you want to change boost levels, get a boost valve. Do not adjust the wastegate rod. My favourite these days is the Grimspeed one. https://www.parkautomotorsports.ca/prod ... fe32&_ss=r

5) Install an EGT gauge and a boost gauge before doing anything. EGT is critical to long engine life. Keep the pre-turbo temperature below 700 C and your engine will be fine. A gauge with maximum memory and an audible high alarm is really helpful to ensure that you stay in a safe zone.

6) Don't overcomplicate the fuel pump settings. Once you have set a boost level you want, adjust the main fueling screw to set the maximum EGT at sustained full throttle to a level that you are happy with. Be aware that EGT changes with rpm, so try and find a long hill that you can slowly accelerate from 2000 rpm to 3500 rpm in order to see how EGT changes with rpm. Once you have the maximum fueling set, adjust the "smoke screw", this is the one on top of the boost compensator diaphragm. Adjust this to set the off boost fueling to get a smoke level that you are comfortable with. No smoke is fine, but you will have a lot of turbo lag. A bit of smoke reduces lag a lot. A lot of smoke does not make much difference over a little.

[andrewMcF]

I drive by EGT alone, where I'm going, the speed I'm going, the little old ladies I run over.... I don't care! EGT is all I look at! lol I kid... but EGT is monitored more then anything.

This is just a pet project and my expectations are very real, I'm not expecting F1 performance... I like to fiddle. :/

I have also found the boost ring to be less then noticeable, thought it was just me! The boost pin, could be placebo but I feel it makes a difference. I didn't actually dyno it.

I do have the fourby boost controller and was planning on putting that on, but I'm wondering why the one you recommended is waaay more $$, there has to be a difference.

in short though, i'll put it all together with EGT(as always) and a boost gauge(was planning too) and get it stock set up, run for a bit and make incremental changes... that's the plan at this point. Using the pin, ring, and vnt turbo... "you get what you get and you don't get upset" :)

Thanks for the response and tips.

Andrew

[red90]

I so careful comparisons logging boost EGT and speed on the same hill back to back with each change. The ring had zero measurable difference.

If you need to watch the EGT gauge you have fueling set too high.

In the end it will never be fast. 2.5 liters and 3 tonnes is not a match made in heaven.

My 3.9 l diesel Defender makes it seem like a broken toy.

[andrewMcF]

I don't "need" to watch the EGTs, I just am super paranoid and only in summer long trips up the mountains... I was more just having fun... in all serious though, I haven't messed with my fueling other then the pin and ring on my current running 300's. I've seen/heard too many stories about wrecked 300TDi's caused by not watching EGTs, and 1 while out with friends. I know own that engine and that's the one I'm building now...

And I don't think I have the skills to drop a 4bt into my trucks so, the 300's is it for me... maybe one day.

If I'm ever out in CGY, love to see the 4bt in your truck and feel that torque pull! lol

This engine is now .040 over bore as that's what was needed to smooth out the bores, what a mess that was. I'm not sure if that get's me up to a 2.6l engine now! All pistons are balanced to the exact same weight with connection rods and wrist pins. Metal head gasket, etc...
Trying to be as meticulous as possible about the build. All the fun things. :/

Andrew

[red90]

Change to a gauge that has an alarm output and connect it to a buzzer. Audible alarms are the only useful ones.

[Seekerbeta]

Maybe I’m the crazy one in the group, but I’ve never felt the need for my defender to be any faster than it is. It has all the low end torque i need to go up the hill, and on the highway I don’t need to be going faster than 75mph anyways! A couple of times i needed to drop gears to climb the coq on the RL trip, but i was following a pile of Defenders anyways so we weren’t trying for land speed records.

[swamijake]

Yes but you have a light little 90. I think the stock 300 in the 90 is a good match. In a loaded 110 it's a little anemic and I'm often wanting a little more. But I suppose if I had a supercharged 6.0 LS I'd still want a little more.

[swamijake]

Red90's advice of good boost and egt gauges to start is spot on.

I very much agree that all three will not blow your engine. Cranking boost up, stock turbo or vnt, and going nuts with the fuel (high boost or not) will both kill the engine in different ways. My understanding (Hasn't happened to me, google reading knowledge only) is that north of 18 ish PSI sustained boost will blow head gaskets. North of 700 degrees EGT for too long will melt things. More fuel increases egt, more air reduces egt. You can do this with a more efficient turbo or better intercooler or even porting and polishing heads .

So my understanding of the boost pin was that the ramp was steeper which would give more fueling under boost without affecting the rest of the fueling vs RPM vs throttle "maps". I've been a bit hesitant touching the main fueling pin after experiencing a solid run away. What I do now when touching the main pin is have the inlet of the turbo open and a CO2 fire extinguisher on hand. If it tries to take off a quick squirt into the turbo inlet stops it right now.

[andrewMcF]

Great explanation swamijake! Thanks.
For my 110 what I'm really looking for is sustained hill climb on the highway at a reasonable speed while keeping the temp down on the EGT... That just basically means a bigger intercooler as I understand it.
This post is more of a, I have a spare 300Tdi, I have wanted to rebuild an engine(never done one), and I have some coins saved up to do dumb stuff like this....
Not looking to do a quarter mile kind of stuff, just trying to get some mechanical experience and see what I can reasonably get out of what I have(without fragging the eninge)... all in fun.

Thanks everyone for the tips!