P-pumped 6.7 observations.

RonA

RonA

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Picked my truck up this evening and made a short(20 mile) trip home with it doing basicly a whole bunch of gentle roll ons the whole way home. Looks like I have a couple of oil leaks I'm going to have to track down, but it ran fine. Hazes the same as the 5.9. Real slight at idle and only a light gray when taking of gently. Rolling into it creates a bit more of a gray cloud, not black. Same injectors(7 x .013), same 13mm pump, SDX Comp DV's, 22 deg timing. I left the pyro probe in #5 like before and appear to have dropped between 50 and 75 deg at cruise(600deg at 65-70mph flat ground). Only my primary boost guage is hooked up so I don't know what total boost at cruise is. Spools similar to the 5.9 181/210 as near as I can tell. The 188/220 is probably being offset by the head Greg at ZZfab ported for me. Also noticed the egt's drop off to 300 in just a fraction of the time compared to before.
 
RonA said:
Picked my truck up this evening and made a short(20 mile) trip home with it doing basicly a whole bunch of gentle roll ons the whole way home. Looks like I have a couple of oil leaks I'm going to have to track down, but it ran fine. Hazes the same as the 5.9. Real slight at idle and only a light gray when taking of gently. Rolling into it creates a bit more of a gray cloud, not black. Same injectors(7 x .013), same 13mm pump, SDX Comp DV's, 22 deg timing. I left the pyro probe in #5 like before and appear to have dropped between 50 and 75 deg at cruise(600deg at 65-70mph flat ground). Only my primary boost guage is hooked up so I don't know what total boost at cruise is. Spools similar to the 5.9 181/210 as near as I can tell. The 188/220 is probably being offset by the head Greg at ZZfab ported for me. Also noticed the egt's drop off to 300 in just a fraction of the time compared to before.
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So spool is the same? I thought 6.7 spooled better.
 
It will be interesting to see how it compares on the dyno to the 5.9 if you get liqured up one day and hit it hard.....considering the glass block and all...:poke:

:hehe: Kidding! I'm sure it will be fine!
 
Joesixpack said:
It will be interesting to see how it compares on the dyno to the 5.9 if you get liqured up one day and hit it hard.....considering the glass block and all...:poke:

:hehe: Kidding! I'm sure it will be fine!
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LOL At that entire post.

I'm curious about dyno numbers too though, just to see the difference in powerband and torque numbers.
 
I'm just giving Bsmith a bad time. More stroke and more cubic inches should spool faster. But head porting can affect it. I just haven't got it broken in enough to try it yet.(or at least not "liqured up").
 
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Very cool to hear. Ill be checking in on this. Best of luck to you Ron
 
Any regrets going to the 6.7? Seems there will be more potential with the head being ported and the spool being the same. Have you posted the power curves of the 5.9
 
All I've done is drive it 17 miles home with just a few very mild roll ons w/no boost gauges. It needed a little TLC to get things back in working order before proceeding.
 
well put some miles on that thing so we can get some feed back!!!!! i thought it sounded a bit different to me but that could be the higher pressure and shorter injection out of that 13mm
 
DEZLFREK said:
well put some miles on that thing so we can get some feed back!!!!! i thought it sounded a bit different to me but that could be the higher pressure and shorter injection out of that 13mm
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Adam.
I got the inner fender tweaked back to shape and bolts in all the mount holes, so tuesday when I have some help here i will try to get the fender back in proper position and bolted down. Then I just have to take off the valve cover and see if everything is in place and properly adjusted, move the pump feed line to the other port, hook up the fuel pressure gauge, check
the pump gear nut and adjustable gear bolts, and check the timing. Should be ready to go then.
 
Mind posting some of the general info about the engine for us guys that are outta the loop? Not a 12v 6.7 head is it?
 
Got the fender straightened out and did a little tweaking today. Took it out this evening and ran it from here(600ft) up to Brownsville(a little over 2000ft). Ran really nice and smooth, and clean. Honestly, it looks like it could use some more fuel. Turbo's appear to be slightly less responsive according to the boost gauge. On flat ground at 60 it's just under 5psi with no movement on the primary gauge. They come up slowly like before and it seems like the primary starts making boost at about a pound or 2 higher on the manifold gauge. Egts are really nice. No problem keeping them down at 800 running briskly up the hill. Rolled it up to almost 30psi at one point and just kissed 900 before the top of the grade. It looks like the head porting may have taken away from the extra bottom end people claim from the 6.7, but it is burning cleaner and if I add a bit of fuel to the bottom it will probably perk the turbos right up. Got an oil leak to track down. I found that the pan bolts weren't very tight and that may be the culprit. I only have the vent in the valve cover and the small one on the front cover so it's probably pressurizing the internals a bit and finding weak spots to send oil through.
 
I don't think a P-pumped 6.7L would ever have the same (okay, similiar) bottom end power/response of a CR 6.7L (I know I am probably stating the obvious here) or would it (assuming the timing is conservative)???

You still running 22* of timing (from post #1) Ron or have you played with the timing a little?
 
If it did eliminate some of the low end it should help keep it together
 
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