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Discussion Starter #1
So I am Teflon and ceramic treating the pistons. It is a big cam 400 cpl 676. I would like to get 475 out of it. I was told that I need to reflow the injectors , get a bigger turbo and reflow pump. They also wanted me to spend$$$$$$. Now I am gonna talk to the guys here cause I am sure u guys know. What do I need to do ?
 

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So I am Teflon and ceramic treating the pistons. It is a big cam 400 cpl 676. I would like to get 475 out of it. I was told that I need to reflow the injectors , get a bigger turbo and reflow pump. They also wanted me to spend$$$$$$. Now I am gonna talk to the guys here cause I am sure u guys know. What do I need to do ?
You only need to turn some screws. About 600 at the crank should be easy without any parts change.
 

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Discussion Starter #3
You only need to turn some screws. About 600 at the crank should be easy without any parts change.
Well I hear that but can anybody be a little more specific please. I would love it to be not so slow taking off and I would like to make it pull all the way to 2100. Not really interested in it reving any higher than 2300 unloaded.
 

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I don't know the exact button that you need, or the timing spec, but you shouldn't need much to get to 475, if you search around for LOGHAULER s threads there are a lot of replies and discussion about the big cam 855, probably has already been answered, Sorry that I don't have the exact specs that you need, but I am pretty sure you don't need to spend a fortune.
 

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Well I hear that but can anybody be a little more specific please. I would love it to be not so slow taking off and I would like to make it pull all the way to 2100. Not really interested in it reving any higher than 2300 unloaded.
You might want to think again that max rpm limit. Those engines want to rev high and don't want to be lugged down, especially when more fuel pressure is given to it. Limit the max unloaded rpm to somewhere around 2900-3000 and never lug it under 1700-1800 under full load when the fuel is turned up, light cruising is ok at lower rpm. If you want to lug it down you need to retard the timing and then you will have problems with EGT.
 

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You might want to think again that max rpm limit. Those engines want to rev high and don't want to be lugged down, especially when more fuel pressure is given to it. Limit the max unloaded rpm to somewhere around 2900-3000 and never lug it under 1700-1800 under full load when the fuel is turned up, light cruising is ok at lower rpm. If you want to lug it down you need to retard the timing and then you will have problems with EGT.
That right here is good advice for a one time hot rod or maybe a few more races but your only going to spend money if your working it for a living doing the rpm that hi.First of all you do need a higher flow injector and a 1" or 1 1/4 gear pump for the fuel. The timing should be slowed some but be carefull because they like cat need the injector tip angle correct for the instant of start of injection. To fast timing will put the fuel on the liner and too slow burns in the exhaust manifold.For a work truck and hi HP don't run rpm over 2200 rpm.
 

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That right here is good advice for a one time hot rod or maybe a few more races but your only going to spend money if your working it for a living doing the rpm that hi.First of all you do need a higher flow injector and a 1" or 1 1/4 gear pump for the fuel. The timing should be slowed some but be carefull because they like cat need the injector tip angle correct for the instant of start of injection. To fast timing will put the fuel on the liner and too slow burns in the exhaust manifold.For a work truck and hi HP don't run rpm over 2200 rpm.
You drive between 1700-2300 when power is needed, most of the time you don't need so you can use lower rpm. High idle is set high because governor is not on/off but drops fuel progessively, if you want it to pull to 2200-2300 you need to set the governor much higher.

For 600 hp you don't need high flow injectors, they don't hurt either but you don't need them. Stock gear pump is good for 1300 hp so why buy expensice gear pump only when Bruce M. says so?

I'm not 100% sure but I think all Cummins injectors have about the same angle. These are not Cat engines and should not be compared to them or any other engines because of PT fuel system. Timing changes in relation to fuel pressure, more pressure more timing. At part loads timing is always very late, thats why you don't want to retard it, especially at moderate power increases like this thread is about. When talking about PT engine, fast timing cracks pistons and stretches head bolts (at low rpm), slow timing washes cylinder liners, smokes, uses too much fuel and burns engine.

Keep it simple and just turn the screws. And learn to drive it right.
 

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Discussion Starter #9
Thank you for the replies. Going to get the injectors from a 475 cpl 586 and have the pump done by pp. Would love to do it myself but unless you guys know exactly what to do to the t , I would rather send it out. I know it's a change of a button and some shims on the pump but don't know which button or how many shims. It's save to say leaving the timing where it stands ?
 

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I have ran those injectors and you will melt your engine trying to work it, the HP you want can be done with your stock injectors, your engine is not timed properly for these injectors, and you will not be able to get the air to the engine that you need to get them to burn clean.

Quit spending money on stuff you don't need just because PP says so. A button change and a little more fuel pressure and you can run at 475 safely.
 

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Also, all NTC injector tips spray at 18*, they don't change no matter what injector or piston is used.
 

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Big Cam Power!!!!!
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484 Posts
So I am Teflon and ceramic treating the pistons. It is a big cam 400 cpl 676. I would like to get 475 out of it. I was told that I need to reflow the injectors , get a bigger turbo and reflow pump. They also wanted me to spend$$$$$$. Now I am gonna talk to the guys here cause I am sure u guys know. What do I need to do ?
475 is very easy to achieve with a few minor adjustments you can open up the injectors a little and calibrate the pump and you will be fine...I'm currently running some 270cc injectors fuel pump work 2400rpm limit I'm making about 35psi of boost ...I do have the 4b turbo and this thing pulls like a mad dawg! This trucks works everyday no issues been running now for almost two years and all my ingredients came from the fine people on this site.....so if you need anything let me know and we will get her running.:peelout:peelout:peelout
 

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Big Cam Power!!!!!
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Thank you for the replies. Going to get the injectors from a 475 cpl 586 and have the pump done by pp. Would love to do it myself but unless you guys know exactly what to do to the t , I would rather send it out. I know it's a change of a button and some shims on the pump but don't know which button or how many shims. It's save to say leaving the timing where it stands ?
if you don't want to go with the 586 injectors pull the one you have, have your shop rebuild those and tell them to open them up some if you don't have reputable shop that will do that pm i'll send you to the place that does all of my work [email protected] Diesel
 

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Big Cam Power!!!!!
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Also, all NTC injector tips spray at 18*, they don't change no matter what injector or piston is used.
I found the 1.25gear pump for 240.00 bucks and it's oem
 

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Discussion Starter #16
So the turbo obviously provides enough boost for 475hp? Are we talking at the crank or at the wheels numbers because am talking at the wheels
 

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So the turbo obviously provides enough boost for 475hp? Are we talking at the crank or at the wheels numbers because am talking at the wheels
a friend of mine dynoed between 480-490 to the wheels just by turning more fuel and rpm to it. No buttons or anything. Max power at 2200-2300 rpm. Thats about 550-560 at the crank. Turbo is good for 600-650.
 

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Big Cam Power!!!!!
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So the turbo obviously provides enough boost for 475hp? Are we talking at the crank or at the wheels numbers because am talking at the wheels
475hp will be at the crank you will have about 380 at the wheels:handshake:handshake
 

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Big Cam Power!!!!!
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So the turbo obviously provides enough boost for 475hp? Are we talking at the crank or at the wheels numbers because am talking at the wheels
What's the status of your truck? Did you juice it up some
 

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Discussion Starter #20
What's the status of your truck? Did you juice it up some
First I wasn't to say thanks for all the help. This past weekend I finally got the truck together and running. I had such a bad experience with this machine shop and the horrible job. The seats and valves were never cut right so on first build all but one cylinder was gurgling fuel. I am happy to say truck seams to be ok. Really cold outside so she has yet to have been up to operating temp. Hopefully this weekend I will finish buttoning her up and grab a load for the real test. The only things that I have done so far is treat the pistons and dual feed fuel lines. Should I see a little over fuel condition at idle with the dual feed lines? Before I do anything else I want to put fuel preasure gauge on the truck to see were I stand as far as fuel pressure already.
 
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