Fellas,
I plan to put a Speedtuning stage 1 or 2 chip in, and I want to make sure my car is "breathing" properly and that I can monitor the engine properly before I install the chip. I went to a tuning shop over the weekend that is going to be putting together a proposal to do some work on my car. Here's what I'm planning to get done:
-3" Stainless Steel straight exhaust pipe off the turbo to my Brabus muffler. This will eliminate the hollowed out trap oxidizer that is currently behind the turbo. Plus, I believe the 3" pipe is a bigger diameter than the OEM pipe.
-EGT Gauge. My preference on the gauge is a VDO that will be closest to an OEM look. This way I can check the exhaust temp once the Speedtuning chip is installed and make sure I'm running at safe levels.

Other options I want or are recommended:
-Air/Fuel Gauge. The tuning guys seemed to think I needed one of these. I'm of the opinion that these are really only for gassers. Any thoughts on why or if I need one?
-Boost Gauge. Again, I don't really think this is necessary. Any thoughts on why or if I need one?
-Larger Intercooler. I will agree that the stock intercooler is really small on the E300 model. Will a larger intercooler benefit my car currently? Will it benefit the car once the Speedtuning Chip is installed?

Thank you for any help. I'll definitely post pics of the process and fabrication.

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Ed
-1984 Mercedes 190D 2.2 5-speed gray market(bought@30,000 miles) (Sold back to original owner@170,000 miles)
-1999 Mercedes E300DT (245,000 miles)
-1999 Mercedes S500 Grand Edition (80,000 miles)

I had a 99 E300 and purchased Speedtunings #1 reprogram, 40hp 80lb tq. Well worth the money! I was planning a 3" exh. system just as you are doing. I had a big problem with that car, and sold it. I do not want to talk about it.
I installed a manual boost controller commonly found on Ebay, cheap. YES, they can be used on a vac. operated wastegate. You just need to keep in mind that you are using it in reverse. You will run two vac. lines to where the breather filter is near the computer. Buy adjusting the unit down it will increase boost and adjust up will keep a stock boost level. I had also tapped a tee line for a gauge. Both the manual valve and gauge were hidden inside the wood lid compartment just below the radio, on a nice black panel.
Now I have a 96 non turbo and I'm adding a 99 turbo manifold and turbo. I need to keep it tame due to the fact that the non turbo motors are not built like turbo models. I will be welding up the 3" stainless exhaust for it though. I will use a pressure wastegate, and turbo injectors.

I think this thread needs moving to the Diesel Performance Tuning page. You may get more replies there.
Best you ask a moderator to do it for you.

Good Luck with your project !!

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

If your "tuner guys" think you need an air fuel ratio gauge on a diesel i think you need to find a diesel tuner guy! Don

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Red Green "This is only temporary,Unless it works!"

97 E300D 157000 miles
87 300TD ?141k? miles

Mods please move this over to the Diesel Performance Tuning section.

In regards to the air/fuel gauge. They said they definitely weren't for sure, but that they would research anything that they do to the fullest. This shop has some pretty exotic custom fabrication on mostly WRX, GT 5.0, GNX Turbos, etc. I'm confident in their mechanical and fabrication skills, I just need to get them the correct information.

__________________
Ed
-1984 Mercedes 190D 2.2 5-speed gray market(bought@30,000 miles) (Sold back to original owner@170,000 miles)
-1999 Mercedes E300DT (245,000 miles)
-1999 Mercedes S500 Grand Edition (80,000 miles)