EXHAUST ON MY 2000 K3500

[MrMarty51]

I did some looking at the exhaust on My truck, 2000 K3500 and found it to have two sections of three inch pipe in it.
With the EGTz hitting to the 1250 and very slightly over, I am wondering how much a four or four and a half inch exhaust system would reduce the the EGTs.
Any recommendations for what size might be the best ?
There is a local shop here that would make the exhaust system but they would not be mandrel bends like what I have looked at in Leroy Diesel, would not having mandrel bends hold back the heat ?

 

[Will L.]

The easiest the exhaust can get out, the better it is. Sand packed bends are better than mandrel bends IF the guy doing them is good. But you will drop around $1,800 for a sand bent exhaust.

Run a down pie that is open dumping just below the pan, and that will show you how much is from the back pressure.

The best egt killers are wmi or an inner cooler.
Cold air in = cold air out. What are you running for a turbo?

 

[MrMarty51]

It has the stock Borg Warner turbo. I would like to modify that, or get a better turbo, there is just no $$$$ for much right now.
I`m guessing that the guy with the pipe shop over here would do the complete four inch exhaust for about $150.00. That is just guessing from other work He has done for Me.

 

[MrMarty51]

With the WMI, is that a controlled injection that is used when necessary ? IE; long hard pulls.

 

[Will L.]

Yes on the wmi. Running an innercooler is the replacement for non stop wmi. Not as effective as a well tuned wmi, but once in nothing has to be done to it. You can run both and get great results.

The ATT or similar will improve mpg to help offset some of the cost, as well as improve power and of coarse will lower egt far more than the exhaust pipe. Read up about @WarWagon trying to burn his up with egt and the ATT. (Listen close and youll hear him yell at me from Az that egt scare is bs with ATT)

The exhaust Price $150 is not bad if he does good work. Problem is the real flow. Companies like Diamondeye dont just take measurements and stuff it in. They do computerized flow testing to engineer where and how the bends effect, so take that into account as part of the price. I am doing my own exhaust for my Hummer, and have went to 4 3/8" to help with my flow and had a friend thats an engineer (that designs water flow piping in the millions of gallons per day stuff) doublecheck my concept. He pointed out some big errors I didn't realize were so bad, slight alterations make a big difference.

Yes, all an expense, but worth it. Figure this: the 6.2 and first 6.5s had no turbo. Now I don't think many diesels can be bought without a turbo and innercooler. Mass production wmi will never happen. Inconvenience of filling up another tank kills sells, otherwise they would be everywhere.

 

[MrMarty51]

I did some searching and reading in the forum, One part was where one of the members had built their own inner cooler. I could not see the pics. though with this browser, maybe I`ll go back and see if IE will open them.
I have looked at innercoolers and there are so many of them, then with the comments about not mounting them underneath the front makes it difficult to tell just what really would work good, be compact enough and be open enough to flow freely.
I will be looking into the WMI systems and I think the DiamondEye exhaust will be the one to go with.

 

[WarWagon]

The above advice is all good, but, optional. Esp on a frugal budget. The biggest problem is GM's exhaust and that includes the "Asthma Attack" turbo. Look at the passenger side manifold pushing the driver's side exhaust past two ports at 90 degrees. Very few members have fixed the manifold problem. (The results from those that have are impressive.)

Yes a good 4" exhaust with a better down pipe. 4" kitty if equipped. This is in prep for a better turbo.

Otherwise why mess with it? Seriously the factory turbo is simply too small for all but low RPM off road and daily driver, UNLOADED. It will run with the turbo backpressure getting extreme and costing you MPG while dumping the heat into the cooling system. Even the knock off HX40II's are worth saving up for. In other words the gain from a better turbo is bigger than all the small stuff without a better turbo. I feel bad for @Will L. as space doesn't allow a better turbo for him. Maybe Turbo Resource out of Lake Havasu can build a turbo that would fit?

Long hard pulls are best served by a even larger towing turbo, but, you trade off the lower RPM leaving from a stoplight.

Will is correct: I have attempted to melt down several of these engines with extreme EGT. Didn't happen. EGT when the ECT is under control is a big unnecessary heartburn myth for this engine. Other engines may melt down at X degrees EGT. Not this engine. 6.5's like yours have a coating on top of the pistons. The 6.2 engine I had didn't have the coated pistons. It sustained 1550 EGT for miles towing a grade with minimal smoke. The only evidence was a burned turbo blanket. Buddy, who was tuning the engine at the time, was ghost white when I was reading the numbers off and NOT taking my foot out of it. No doubt from having visions of walking from the middle of nowhere. From extended high EGT's I recommend wrapping the downpipe past the passenger floor pan as the exhaust can burn the paint in the area. And the burned paint (both sides) on the floorpan was from 1400+ sustained EGT with a factory turbo for over 10,000 miles towing 550 miles a day up the Mongolian Rim to 7600'+.

The take away from this is:
1) Top piston coatings are for longer oil life. I have shortened oil life on that hot rod 6.2 with an ATT and BD spool valve.
2) Timing is a big factor. Over advance timing and melt any diesel down with low EGT.
3) EGT is a decorative gauge on the dash that tells you how hard the engine is working.
4) You loose control of ECT with hard work... Well you keep ECT below 210 or you have run out of cooling system with the hard work and bad things happen: Scuffed pistons, heat damage to rings that now have high blowby... ECT is related to EGT, but, with ECT under control EGT doesn't matter.

Note: I do watch and limit the EGT's on the Cumapart because it's a different engine with known ways to fail from high EGT like dropping a valve seat.

 

[MrMarty51]

Thank You very much Will and War Wagon for Your responses.

On the long pulls the ECT did climb to about 215*, that too was a concern. I`m thinking now of adding some of that wetter stuff and seeing if that will help. After reading in the forum about it.
The coolant pump was new shortly before I received the truck. I didn`t like the ECTs when pulling home the trailer with My 93 GMC on it, I changed thermostats first thing and did remove the top shroud and grill, got the oil cooler out of the way and cleaned out the radiator so I think that part of it is all good to go.
Good to know that the EGTs can run as high as 1500* without causing a catastrophic failure. I was very very concerned when I seen the temps climb above the 1250 range.
The ambient temps that day was in the mid 90s too.
I like what I was reding about the ATT turbo, I too am looking more for MPGz than I am performance but, it seems that the ATT gives a person the best of both. That will be on the shopping list too. Hopefully within the next couple of years I can be cleared of a few bills and be able to really go to town on this truck.
I had wanted one of these for a long time, took about two years to find the right one, with everything that I was looking for.
The more i drive this truck the more I like it, even with its faults, it just keeps getting better all the time. Every rig I have ever bought, it takes a couple of years to get it to where it is what it should be and better than factory.
This truck is definetely a keeper.

 

[Will L.]

What fanclutch / fan do you have. If not sure, post a pic.
215 is get nervous time. At 220 pull the hell over. Many will say 220 is ok- and it is ok- ok to put new rings, ok for new bearings, ok to crack a block- etc.

And don't let traffic behind you get you to push too hard. They are not paying for your engine if it lets
loose.

Like WW is saying the egt is just an indicator to look at ect gauge. I know how it feels to have a list of goodies like better turbo and have to wait. Just do what you can when you can.

 

[MrMarty51]

What fanclutch / fan do you have. If not sure, post a pic.
215 is get nervous time. At 220 pull the hell over. Many will say 220 is ok- and it is ok- ok to put new rings, ok for new bearings, ok to crack a block- etc.

And don't let traffic behind you get you to push too hard. They are not paying for your engine if it lets
loose.

Like WW is saying the egt is just an indicator to look at ect gauge. I know how it feels to have a list of goodies like better turbo and have to wait. Just do what you can when you can.

I`m sure it is all stock original, Another upgrade needing attention as money will permit.
I did keep on going at the 215 temp. Next time I will let out of it and get the temps back down. I surely can not afford an engine at this time in my life.

 

[ak diesel driver]

Being a 2000 he should already have the 9 blade and balanced flow WP

 

[Will L.]

Yeah, that is what I was thinking, but thought it would be worth checking. Ive seen stranger things happen, haha. How old the fan clutch is and if he doesn't have Kennedy's it might help to do that also.

Marty, what we are referring to is: your fan clutch should attach to the water pump with a 1 giant nut. look at the front of the fan clutch to the spiral bimetal spring to see if it is plugged full of dirt or is there is a greasy material all over the spring. It should be clean, if not do your best on it. Fan clutches are normally a 5 year lifespan. Just another couple hundred bucks of yours I'm trying to help you spend. DO NOT buy one with out mentioning which one, there are a lot that save you $40, but suck. Until Leroy comes out with his 100% lockup electric, kennedy diesel has the one to get.

You can tell my wife doesn't like when I say it's time to go parts shopping- haha

 

[Hill Top]

The most noticeable things you can do for the least price are, No 1 the exhaust (it's a must), No 2 turbo master along with turning up the pump a bit, No 3 the Kennedy fan clutch. This woke my truck up. I just ordered the ATT as my next upgrade.

 

[MrMarty51]

Yeah, that is what I was thinking, but thought it would be worth checking. Ive seen stranger things happen, haha. How old the fan clutch is and if he doesn't have Kennedy's it might help to do that also.

Marty, what we are referring to is: your fan clutch should attach to the water pump with a 1 giant nut. look at the front of the fan clutch to the spiral bimetal spring to see if it is plugged full of dirt or is there is a greasy material all over the spring. It should be clean, if not do your best on it. Fan clutches are normally a 5 year lifespan. Just another couple hundred bucks of yours I'm trying to help you spend. DO NOT buy one with out mentioning which one, there are a lot that save you $40, but suck. Until Leroy comes out with his 100% lockup electric, kennedy diesel has the one to get.

You can tell my wife doesn't like when I say it's time to go parts shopping- haha

YUP, one big nut. I had it off when I installed new timing chain/sprocket set. The clutch was clean, no leakage what ever.
Kennedy it will be, I`ll check the prices and that might be something I can get real soon.

The most noticeable things you can do for the least price are, No 1 the exhaust (it's a must), No 2 turbo master along with turning up the pump a bit, No 3 the Kennedy fan clutch. This woke my truck up. I just ordered the ATT as my next upgrade.

I did stop at the pipe shop today, He said the biggest pipe He can bend is a 3", so that will definetely be the DiamondEye system.
I do have a turbo master that I had built, it did drop the EGTs by a long ways, highest pulling a heavy boat over some mighty steep grades was 1000* and running 8 pounds of boost, it did increase fuel consumption by two miles to the gallon, measured over quite a few fillups. I got the terminals on the computer/vacuum cleand up real good and reverted back to that system. Have not had any runs without haulig a trailer behind to see where mileage is now at.
The ATT will definetely be on My mind until I can get one and get it installed.
A lot of good people in this forum, making sure that things is done right.
Thank you guys very much.

 

[Hill Top]

YUP, one big nut. I had it off when I installed new timing chain/sprocket set. The clutch was clean, no leakage what ever.
Kennedy it will be, I`ll check the prices and that might be something I can get real soon.


I did stop at the pipe shop today, He said the biggest pipe He can bend is a 3", so that will definetely be the DiamondEye system.
I do have a turbo master that I had built, it did drop the EGTs by a long ways, highest pulling a heavy boat over some mighty steep grades was 1000* and running 8 pounds of boost, it did increase fuel consumption by two miles to the gallon, measured over quite a few fillups. I got the terminals on the computer/vacuum cleand up real good and reverted back to that system. Have not had any runs without haulig a trailer behind to see where mileage is now at.
The ATT will definetely be on My mind until I can get one and get it installed.
A lot of good people in this forum, making sure that things is done right.
Thank you guys very much.
View attachment 50760

If your EGT's dropped after the install of your DIY turbo master, you need to turn up the IP pump up. The TM is to prevent the turbo fall off that the factory control has, it doesn't affect EGT that way. Your lower mileage is result of less efficiency, being in a lets say fuel starved condition, with the factory turbo less fuel versus boost, means less heat, thus lower EGT. Your leaving HP and torque on the table. In this case lower EGT isn't a good thing it shows your not getting what you could from it. If you turn up the pump your mileage will come back as well for the same reason. We all go through this when we first start tweeking.

 

[Will L.]

I remember talking to Bill Heath one time about egt to see if I was being to relaxed about the numbers. I asked him "How far would you drive at 1100egt?" His response "To the Moon and back. I don't even pay attention until 1300."

Bill isn't my hero, and I disagree with him on some key points. But even we are on the same page w/ egt.

You said 1000?!? That is barely awake on an idi diesel. Same with 8psi. 10-11psi on stock turbo all day long is fine.

 

[Jaryd]

If your EGT's dropped after the install of your DIY turbo master, you need to turn up the IP pump up. The TM is to prevent the turbo fall off that the factory control has, it doesn't affect EGT that way. Your lower mileage is result of less efficiency, being in a lets say fuel starved condition, with the factory turbo less fuel versus boost, means less heat, thus lower EGT. Your leaving HP and torque on the table. In this case lower EGT isn't a good thing it shows your not getting what you could from it. If you turn up the pump your mileage will come back as well for the same reason. We all go through this when we first start tweeking.

He would have to get the pcm re flashed in order to get more fuel. i wish we were able to turn the screw on these pumps like y'all.

@MrMarty51 When you do get the ATT, I would get the kojo tune to match the ATT or get in touch with Quadstar Tuning and get him to set you up with a tune to go with the ATT. After I get the diamond eye exhaust on my truck, I'm going to start saving for the ATT and a Quadstar tune.

 

[Hill Top]

He would have to get the pcm re flashed in order to get more fuel. i wish we were able to turn the screw on these pumps like y'all.

@MrMarty51 When you do get the ATT, I would get the kojo tune to match the ATT or get in touch with Quadstar Tuning and get him to set you up with a tune to go with the ATT. After I get the diamond eye exhaust on my truck, I'm going to start saving for the ATT and a Quadstar tune.

I forget everyone doesn't enjoy the simplicity of the DB2!

 

[MrMarty51]

The exhaust was blowing black smoke when the EGTs were at 1250 and the boost was running at 8psi. I thought that the boost should have been higher with that load and that much smoke. It was leaving a cloud behind.
I wonder if a kojo tune would fix some of that with the current turbo ?
@Will L. I guess I was being too concerned over nothing, about the EGtz, I had reafd in Bills article with the suburban about Him doing test runs before tune and Him not wanting to get over 1250*, and so I was thinking that must be near the melting point. LOL

 

[Jaryd]

Yes. A tune would help with the fuel problem. I would tell them you are sticking with the gm8 until you can get an upgrade and see what they could help you with. I would think that if you got a tune now for the current setup you have with the gm8 and then down the road upgraded to the ATT, they may not charge as much just to re flash for the new setup since you have already been a customer and they have already been in the pcm one time.