Posted by Bruce in stinky, smokey , soon to be wet BC [108.162.245.175] on Friday, September 18, 2020 at 20:48:40 :
In Reply to: Re: boost posted by Michael HERNKE [162.158.187.226] on Friday, September 18, 2020 at 15:58:16 :
My head was cracked at 50 thousand miles. I got a new head after some talk with a s hop but kept the old one. It is quite possible to drop in new seats and the head will work fine for years if not decades. Same goes for running it with cracks. If the cracks do not run into a water jacket or promote valve seat wear you can run them for years. Only reason I went to a new head is I use the truck on long trips.
Injectors - leave them alone if they have been serviced. I popped mine out - they were the 9mm versions and machined them down to 7mm for the new head. I checked the spray pattern with nothing more than firing WD40 through the nozzles. All the patterns were the same. I may build a tester to check the pop pressure but these injectors are really simple and last for 100s of thousands of miles. I looked to see if there was a better design or improvement - never found one. Lots of bigger bores but nothing showed up that creates a better burn profile.
Exducer - thats the exhaust side - you want about a 9cm exducer or even a 6 - the number will be cast on the inside of the exducer. Stock was 18 - I hear the later versions from Cummins was much smaller.
Just had it out for a little burp and test run. Now hitting 23 - 25lbs of manifold pressure when I put my foot in it. I suspect it will run around 10lbs at 60 -65 miles an hour on the freeway but there is no freeways around here:)
Going to park it and start looking for a dead short.
I have the silencer ring on both turbos - they are quite quiet compared to when my HX30 had no ring - I created one on the lathe.
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