popping noise 2nd video.....

John Robinson said:
Yes i did a leak down & could hear hissing in the stack....54 percent leakage too...
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Damn 24v guys.......probaly more loose seats. Thier what caused the bent valves.

Why not go back to a 12v head, fewer parts/weight and no more seat issues. Scheid proved thier not all that bad. Also might make a pass with just your secondary charger with less rpm and see what happens. 71mm single was all I ever ran; 5.40's / 8.60's on fuel was no problem. Our light weight cars are running away from the load so fast, single charger makes more since to me [broader torque curve, not so peaky] . Dont take the retired and retarded guys word for it though....
 
Definitely sounds like a pump issue to me. Do you have egt probes for each cylinder on the race pac
 
Looks to me like your youtube user name is the issue. Posting vids of a Cummins race car with an Izuzu user name??
 
The valve seats are no more.......What was causing the bending was the heat....When i would shut her off at the end of the track those exhaust valves that are open would bend...Started rolling the motor over after i shut her down & it vastly improved that...
I do have individual egt`s & the hottest one i have is 1600 at the end of the track.
 
John Robinson said:
The valve seats are no more.......What was causing the bending was the heat....When i would shut her off at the end of the track those exhaust valves that are open would bend...Started rolling the motor over after i shut her down & it vastly improved that...
I do have individual egt`s & the hottest one i have is 1600 at the end of the track.
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Good to hear that you did away with the press seat deal any way, Charlie had told me in years past that he welded them in for thier stuff thier at Dr. P. Not sure about the theory of warping after setting there hot never heard of that one, I used to run 23/2400* every pass when my engine was in the truck and ran three seasons w/o ever bending a exh. valve. I'd be looking at seat and over the nose pressures on those springs. I was def. thinking fuel before but now after see such bad leakdowns and bent exh. valves; Id say that was your valves floating. The second that tappet losses contact with the cam lobe all power is lost, that would explain why it stuffed out the chargers so fast also???
 
This may be a stupid question but were the egt's low on any individual cylinder? Showing a lack of fuel to that cylinder maybe?
 
I would say not enough case pressure or your not holding enough case pressure or something going wrong with the cam in the pump
 
Im proly wrong in every way but could it be the valve seats are welding them selfs to the valve each time it gets hot? i had a 7.3 do that, I was just wondering
 
Well we are going to try a few things in the first pass` at TS & see if we can eliminate some of the possible issues....Time will tell. Thanks guys for all the input.
 
Nothing at idle, pops when it loads the tires and boost comes up. Too much overlap on the cam, just a guess. Oh and I don't like girl scout cookies.
 
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GRotman said:
Listen to the first 10 seconds or so of this video. The cam in this pump was shot!

http://youtu.be/sKzkABf4DK4
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Thats waht Im thinkin too, i had a lobe on a pump cam wipe, I hooked a test line up to it with an injector shooting in the air. It would spray fine at idle and once it had a little bit of rack travle it would stop then full throttle it would spray again...... Same sound
 
Isnt that a 14mm pump from industrial?? Thats some spendy cash if it wiped itself out.
 
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