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My 1999.5 F250 Super Duty with the 7.3 liter turbo-diesel failed the #8 injector recently.

Since I am on vacation for the whole month of December I pulled the injectors and sent them off to http://www.diy-injectors.com/ for rebuild. Mr. Rose rebuilt them to his Stage 2 with larger nozzles to give me 50-60 more horsepower. I will not have to have my computer reburned since I did not opt for the single shot injector upgrade that all the diesel rodders like.

He rebuilt them last weekend and I should have the truck running by this weekend. He said my injectors were in fairly decent shape but had a few broken springs but the #8 cilinder injector was fine.

I also replaced the glowplugs.

I think I have an entrained air issue so I will be installing one of these http://www.fassride.com/ to eliminate the air from the fuel.

I hope the #8 piston is okay.

If anyone needs injectors serviced I highly recommend DIY Injectors.

Anygunanywhere

Well, that's pretty cool.

you got one of those 5" exhausts that looks like a leafblower???

Not yet. I ought to at least get the bigger turbine exhaust down-pipe since that is a restriction.

The 7.3 does not do well with the 5" unless you are cranking out tons of horses. The 4" works better as I understand it for milder mods.

Gun stuff has been a priority lately since the truck is not my main motivation any longer. We just use it to pull the RV and haul stuff.

Anygunanywhere

That's cool. I know very little about Diesel Engines (other than they are loud!).

I have 3" tips on my truck, and when I had them put on, I was going to go for the 2" cause I thought it woulda been better looking, but was corrected by the mechanic dude that put'em on. He was right, too.

DoubleJ wrote:That's cool. I know very little about Diesel Engines (other than they are loud!).

I have 3" tips on my truck, and when I had them put on, I was going to go for the 2" cause I thought it woulda been better looking, but was corrected by the mechanic dude that put'em on. He was right, too.

Gasoline engines and diesel engines respond differently to performance exhaust.

Gasoline engines rely on the exhaust manifold/header to improve "scavenging" and require a certain amount of backpressure. Too large an exhaust will cause a gas engine to lose horsepower. This is a problem those rice burners with the huge mufflers do not realize. Besides being noisy, the big muffler on a stock engine can be bad news. IIRC this can lead to burned exhaust valves.

Naturally aspirated diesels are similar to gasoline engines to a certain degree.

Boosted engines are a different animal. The turbocharged diesel exhaust between the engine and turbo is pressurized and the exhaust downstream must freeflow to recover the maximum power from the exhaust gas. The larger pipe downstream of the turbo also decreases turbine spool-up time and improves response along with decreasing exhaust temperature at the turbine inlet. High exhaust temperatures (>1,200 degrees F) will kill a diesel.

Anygunanywhere

Hmm! learn sumpin' new everyday.

I think mah truck can handle the 3" tips, the rest of the pipes are somewhat normal sized, just dual (afaik).
but I get what you're saying, I never wanted the leafblower on my VW Jetta (when I had it) simply cause I thought it was stupid looking/sounding (I mean really, it's a 4 cylinder!!!!), but sounds like there's another reason.



sorry for thread drifting and all that, btw......

anygunanywhere wrote:

DoubleJ wrote:That's cool. I know very little about Diesel Engines (other than they are loud!).

I have 3" tips on my truck, and when I had them put on, I was going to go for the 2" cause I thought it woulda been better looking, but was corrected by the mechanic dude that put'em on. He was right, too.

Gasoline engines and diesel engines respond differently to performance exhaust.

Gasoline engines rely on the exhaust manifold/header to improve "scavenging" and require a certain amount of backpressure. Too large an exhaust will cause a gas engine to lose horsepower. This is a problem those rice burners with the huge mufflers do not realize. Besides being noisy, the big muffler on a stock engine can be bad news. IIRC this can lead to burned exhaust valves.

Naturally aspirated diesels are similar to gasoline engines to a certain degree.

Boosted engines are a different animal. The turbocharged diesel exhaust between the engine and turbo is pressurized and the exhaust downstream must freeflow to recover the maximum power from the exhaust gas. The larger pipe downstream of the turbo also decreases turbine spool-up time and improves response along with decreasing exhaust temperature at the turbine inlet. High exhaust temperatures (>1,200 degrees F) will kill a diesel.
Anygunanywhere

Thats why serious diesel modders go for water injection to cool the combustion gases, plus the expanding water helps diesels gain insane torque!

I am not that serious.

Injectors arrived yesterday and they are going in now.

Sure is cold in the garage but maybe the skeeters will not be as bad today.

Anygunanywhere

I've heard of those guys, but have never had any dealings with them.. Hopefully I wont have to, 212K miles I'm sure the day is coming. I've had a few injectors in my 6.0's replaced under warranty though..

I dont know if you tow a lot or not, but I'm sure you've experienced turbo surge haven't you? Google up Wicked Wheel. It's a turbine wheel that gets rid of turbo surge. No performance boost, but turbo surge can snap the shaft ( boost pressure is too high for the amount of exhaust pressure to turn the wheel ). Although it will help with performance because the surge is gone, and will allow high boost pressures you couldnt get before because of it stalling out. I haven't bought one yet, but I intend to soon. I dont haul a lot this time of yr, so I'm not to worried about it.... For the most part, the exhaust housing on the 7.3 is to large. It's like that to decrease EGT's, but thats a cheap, bad way to do it... This is why everyone is going to variable vane turbo's, small turbo at low boost and RPM, big turbo at high boost and high RPM.. It's the best thing since electronic fuel injection.


Another tid bit on diesel exhaust, or any turbo engine.. We all know that exhaust flow is what makes things go round. But heat is also one of those. When air is heated, it expands, therefore you have more "energy" to spin the exhaust side ( the term slips my mind right now ). If you lower the exhaust temps to much, you lose exhaust volume, so there is less energy. There is a fine line between the right exhaust temp, and mechanical limitations. The 7.3 for instance, you never want to run the engine more than a minute or two at 1500 degree's. A 6.0 PSD you want to limit that to 12-1300 because they use aluminum heads. Post turbo, you want to keep the flow, but you dont want a sudden cool down of the exhaust temps. A 4 inch downpipe is perfect for most ( 5 inch only on heavily modded diesel's ). If you want a power gain, have the downpipe ceramic coated. It will retain the heat, which helps "draw" the exhaust flow out.. I haven't seen any dyno charts for this on a diesel, but on a gas engine you could see 20 HP on a properly designed exhaust system ( gas or diesel, the principal is still the same ) just by ceramic coating the downpipe. It's not cheap, and it takes a few weeks, but if your like me, looking for every last bit of power out of a combination, it's worth it..

I installed the new injectors and the additional fuel is noticeable but now I must do something to the exhaust. EGTs are hotter.

Anygunanywhere

How do you like the new power? 50-60 HP is a big gain.. Do they advertise TQ numbers? I often dont look at HP numbers on a diesel. A 350 HP diesel might make 500 ft/lbs of TQ.

How high are the EGT's running?

Magnaflow makes a nice exhaust kit, I dont have one on my 7.3 though, it's more of a custom job.. I'm a dealer for them ( as well as Edge and the other big names ).. If your wanting to do something with exhaust I suggest you give them a good look.. I've been very pleased with their stuff. As many installs as I've done, they pretty much fall right on. You can do it in your driveway no problem.

I don't have any torque numbers but the truck accelerates nicely which translates to torque when you are talking about a 6000 lb+ truck.

With my foot in it the EGT walked up to 1200 deg quickly.

I dropped my fuel tank yesterday to do some in-tank mods to eliminate air in the fuel. Once that is done I will check out the exhaust systems available. I have read where I can achieve 90% benefit of exhaust flow of a 4" by just changing the turbine exhaust down-pipe and swapping out the stock muffler for the Walker Big Truck muffler.

I have the Ford AIS air intake and modified the inlet system for max air so exhaust is next.

Anygunanywhere

How is drive ability? Mine has the problem of not wanting to go slower than 40 MPH, and thats with your foot off the petal When the roads are slick I have to take all the programing out of it, the throttle response is so quick and sometimes violent it can get ya in trouble.. Eats up tires too, I always laugh when I leave a parking lot, I look back and the tires are smoking .. I'm worried that injectors might make the "problem" worse.. Seeing how I dont have a problem with EGT's, I'd like to add a bit more power, although the truck really doesnt need it, it's still nice to have

Can you give me any details about the tank mods? I've considered putting a FASS pump on mine, which is designed to take all the air out of the fuel. When driving hard, which I hardly do anymore, it starts to starve for fuel, but does not lose fuel pressure. So I'm guessing it's air in the system. I'm not so into truck performance I'm willing to spend that much for a aftermarket pump, I'd rather spend that money on the race car.. A buddy of mine has a Fass pump on his Dodge, that truck is quick, he cant keep up with mine until it starts starving for fuel. Talking about speeds that are far from legal though. So I imagine if he felt the need to put one on his, I should have done something long ago ( although Dodge's dont have the strongest factory fuel systems )...

I'm getting ready to put a Edge w\ Attitude in my 07 F-450. Had one laying around I pulled off my dad's 05 6.0 when we put a Edge Platinum on it. Kinda worried about EGT's in that thing. My dad's has a Magnaflow exhaust with 4 inch downpipe, it starts cutting fuel after about 1/8th mile to lower EGT's. That F-450 has a 2 ft extended on to the frame, with a service bed.. Dont know what that thing weights in it, but she's a big girl.. Stock 6.0's will get ya run over getting on to the highway though, they have power, if your willing to wait for it

Bunkins wrote:How is drive ability? Mine has the problem of not wanting to go slower than 40 MPH, and thats with your foot off the petal When the roads are slick I have to take all the programing out of it, the throttle response is so quick and sometimes violent it can get ya in trouble.. Eats up tires too, I always laugh when I leave a parking lot, I look back and the tires are smoking .. I'm worried that injectors might make the "problem" worse.. Seeing how I dont have a problem with EGT's, I'd like to add a bit more power, although the truck really doesnt need it, it's still nice to have

Can you give me any details about the tank mods? I've considered putting a FASS pump on mine, which is designed to take all the air out of the fuel. When driving hard, which I hardly do anymore, it starts to starve for fuel, but does not lose fuel pressure. So I'm guessing it's air in the system. I'm not so into truck performance I'm willing to spend that much for a aftermarket pump, I'd rather spend that money on the race car.. A buddy of mine has a Fass pump on his Dodge, that truck is quick, he cant keep up with mine until it starts starving for fuel. Talking about speeds that are far from legal though. So I imagine if he felt the need to put one on his, I should have done something long ago ( although Dodge's dont have the strongest factory fuel systems )...

I'm getting ready to put a Edge w\ Attitude in my 07 F-450. Had one laying around I pulled off my dad's 05 6.0 when we put a Edge Platinum on it. Kinda worried about EGT's in that thing. My dad's has a Magnaflow exhaust with 4 inch downpipe, it starts cutting fuel after about 1/8th mile to lower EGT's. That F-450 has a 2 ft extended on to the frame, with a service bed.. Dont know what that thing weights in it, but she's a big girl.. Stock 6.0's will get ya run over getting on to the highway though, they have power, if your willing to wait for it

I have not really put any miles on it since put the injectors on.

It is up on jackstands now with the fuel tank on the floor of the garage. In-tank mods: http://guzzle.rbmicro.com/harpoon.html and http://guzzle.rbmicro.com/hutch.html.

I am waiting on this to do the "Hutch" mod. I bought the kit without the filter: http://www.itpdiesel.com/store.php/products/73L_TankKit They recommend to use a filter between the tank and pump but since I am thinking about the FASS I did not buy the filter.

I hang out at http://www.thedieselstop.com/. There is tons of info for Power Stroke owners there.

Anygunanywhere

Thanks for posting the links I've spent a little bit of time on the dieselstop, I have a account, but I sure cant remember what my user name is and so forth Always spending time on other forums, way more than I should.. Maybe I should change my habits a bit, been having a few minor issues with the truck that I haven't taken the time to find yet, I'm sure I can find the fixes there..