Turbo question... I'm new to these trucks

[xtrempickup]

Hi, First post to this board and i've had my 95 Sierra 6.5L Turbo Diesel since July. I found tonight that the wastegate actuator is SHOT. it had wire tieing the wastegate shut or close to it so it boosts. I've done the same on most of my turbo cars to get better boost instead of replacing a bum actuator. I looked at this one fast, looks like it doesnt come off the wastegate, like its welded in place to the rod off the can. I might be off, its 930 and dark out and cant see much. Question is has anybody replaced their wastegate actuator before on this type of type and if so where can i get one thats good, new or used, I don't care.

[gmctd]

Welcome to the forum, X...........

Check out Heath Diesel for replacement actuators, spring or vacuum, and wastegate solenoids and such.

You may enjoy his site.

[NYCEGUY01]

Turbo-master x2

[xtrempickup]

i'm a litle slow here, I know a lot of places, but some website names that you are talking about would be helpful.

[Hubert]

Its heathdieseldotcom or similar you could google it. He has a spring controlled wastegate mechanism for the 6.5 trucks that works well.

You have to have a boost gauge or way to measure boost to set it correctly though. Note with strong emphasis gauges are highly recommended for the 6.5 engine.

Alternatively you could fix the OE system back up it does have a useful purpose and actively controls wastegate with ECM program. It can also be tuned electronically for more performance and still retain some of the OE design safeties. Kennedydiesel.com has an electronic fooler mechanism.

[xtrempickup]

i have both the EGT and Boost gauge from Banks. most turbo systems are MAP controlled, its not hard to fool them. i just want it working. I wonder what the stock setting is supposed to be

[Robyn]

A 6.5 is a fussy engine in that they are not inter/after cooled and are very susceptable to high Exhaust gas temperatures (EGT)
Fooling the system can build more power but at the same time also put your little diesel Rat in jepardy of a melt down.

The gauges are the only way to know what you are doing and when to get your boot out of it.

If you are going to mess with the boost mechanism you really need to get a bigger and more free flowing exhaust system on the truck.

My recommendation is to fix the stock system first and get it working so the computer can controll it and then go for an exhaust system that will flow some real air volume.

Once you get the exhaust system working well you can go for a boost controller change and then an ECM upgrade so you can get some fuel into it to use the boost.

[Hubert]

I THINK the stock boost level is about 6-8 psi. What did you get normally before problems? I put my boost gauge in with turbo master and set it for 10 psi max.

The turbomaster is a dumb spring and controls boost via turbine/wastegate pressure. It will build boost according to max setting or depending on pyhsics of heat (throttle input and load). The OE ECM/Vaccum controls does some things controlling depending on throttle input and rpm.

I read it on here some and measured OE vac at wastegate solenoid to diagnose boost once and found the ECM lowers wastegate holding force at light throttle (3-5%) at 2000 rpm +/- cruise (where there is little need for boost). I think to increase economy and lower continuous stress on head gasket. Seems I have read it will also lowers boost I think at 2800 + rpms. The main thing is it will lower boost if it senses high IAT, high boost, and high coolant temps as an attempt to reduce overheating damage. Exact criteria for event I am not sure and its not recommended to trust it saving the engine towing heavy uphill.

Its been debated several times which control system is better suited for safety, performance, and/or economy. Simplicity won out the debate for me.

You may want to add the gauges in your signature its one of the things people look for to kind of judge your knowledge until we get to know you.

[xtrempickup]

well i bought it this way, it has a banks add-ons, i dont know if any chip at all, has the dyna fact pillar pod with gauges and the airtunnel in the fender to the gail/banks airbox. I dunno, this thing was running consistently about 12-15 lbs. No wonder it felt powerful, maybe i wont replace and just rewire this gate closed a little, I know the fuel and EGTs are good, this thing dumps a load of fuel and black smoke in high boost

[Hubert]

Well read up on the 6.5, compression, indirect injection, GM-X turbo's etc. a while. 12 psi is considered max w/o intercooling. 14 psi should be about safest max w/ intercooling. I really can't / should not try to argue 1 psi but its for safety margin. Wiring a wastegate shut or near shut is dangerous. High non intercooled boost will stress head gaskets and probably eventually blow it somewhere and/or may damage pistons and cylinders.

[xtrempickup]

you dont have to tell me about HGs going and pistons trying into ashtrays. Diesels take a lot more than the turbo gas 2.2Ls I build and race and drive daily. My daily can run 20psi on 93 without any problems only being Intercooled. Diesels are less prone to detonation and it also is cold outside, I touched my turbo tonight after driving, One its warm, not hot and 2 my EGts are low. I dont know how long the truck was like this before i bought it, but i've driven 5 months on it the way it is with no ill effects. I adjusted the boost down to 5 psi to redline til i can set a baseline. Intercooling this motor is hard, I cant just mount a cooler and run the piping, same with adding a BOV to it. Its strong I'l say that much, but probably selling it in 2008 when NJ makes it mandatory for diesel trucks to undergo Emissions testing. right now my truck has an exhaust stack in the bed, also not installed by me. lots of things on this truck that arent stock and a lot done pretty shady leading me to suspect by a less than smart owner.

[Hubert]

Did not mean to sound like I was talking down to you or mean anything by my post but you need to read specifically about the 6.5. A stock 6.5 is really not a heavy (or even medium) duty diesel by most all accounts (it was a light duty diesel designed for the masses). It won't take higher boost greater than 14 psi because of the high compression. The 6.5 compression is about 22:1 significantly higher than most other pickup truck diesels (newer ones are about in the 17:1-18:1 range) and way more than the 2.2 gassser. Read the threads by ronniejoe and others - lots of threads on this subject here. I can't do it justice in short order.

On edit:
There will be some fairly big differences in performance comparing a sport truck set up and a towing truck. Even more difference when comparing flat land to hilly performance. The 6.5 can be a peppy engine with mods but still will not tow like a cummins or other direct injected engine due to the heads getting so hot.

[xtrempickup]

yea i hear that part, I was looking for a Cummins but out of my range and also my body style. I wanted something better on fuel than my old 4.3 Gas and strong cause I do a little towing of cars and wanted some balls for my buck. are there chips for this motor? i really don't wna mod it as its my daily driver. Its nice to be able to roast 35in A/Ts and look sick doing it. Is there a posi set up out there for these rear ends and the LSD for the front?