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Discussion Starter #1 (Edited)
Hi all,

For those of you who were following the saga about the broken injector stuck down in my cylinder head, I finally got it out. I dribbled candle wax down into the hole to block it, then we drilled/tapped the bottom of the injector body where the nozzle sticks through. Threaded a bolt in, and out it came. Long story short, I cleaned everything up as best I could and installed the new injectors. The injectors are the only change that was made.

Now for the good part: I test drove the truck, but it's drizzling. Second and third gear are useless on wet roads at full throttle of course-the truck will fishtail until you let off or it hits the governor. Fourth is a crapshoot-sometimes it would bust the tires loose. Seat of the pants, there is a moderate power increase. Spoolup seems maybe a little faster, but I have no afc in my pump, so that's probably mostly my fault. I need to reinstall that and tune it correctly. I may well do that tomorrow.

The timing seems to have been retarded a bit, as I immediately noticed the engine sound wasn't as sharp. It sounded more like a stock 12v. I'd imagine the pop off pressure of these injectors is higher than my old ones, which would explain the timing. If so, when I get the timing back where it used to be, I expect I'll find even more power.

Boost-two days ago I ran it hard and watched my boost gauge. The max was 41 psi. Tonight the max was 49 psi. No changes were made to the wastegate between these two observations. That tells me right there that the injectors are delivering more than my old 370's were, just like Jamie said they would.

In summary, the injectors have already shown a worthwhile improvement, and that's on a wet road with what I strongly suspect is a couple of degrees less timing. I'm a happy camper.
 
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saggin pop pressures will give you that "feel" of a timing retard once you put new injectors in with a fresh pop pressure.
 

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Awesome Bud! I'm glad to hear you got them up and running. I told you those injectors are sweet. Keep me posted & have some fun!
 

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Discussion Starter #5
Yeah, I was figuring the fresh injectors were opening a little later. I should be able to compensate for that with a degree or two of extra timing. I bet with the afc set up and a little more timing it'll run pretty well.
 

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Discussion Starter #7
It was set to 15.5 to 16 degrees about 5 yrs ago.
 

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Discussion Starter #9
Uh uh, not with the stock headgasket and bolts.
 

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staring at my brand new .020 over gasket, P&P'ed head, and other assorted gaskets as we speak.
 

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Discussion Starter #11
I'd like a ported head, or better yet, an aftermarket head from indy cylinder heads. The MSRP of their new aluminum 12v head is $8000, too much for me. They're rumored to have an iron version in the works-maybe I could afford that eventually. Poor head flow is probably the biggest bottleneck to performance on these engines. As well as they perform, not having to run so much boost to get a given airflow sure would be easier on turbos, not to mention cutting losses down due to reduced drive pressure.
 

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well the head, as it comes stock, is good for about as much air flow is as need in a 200hp application.............the good news is, if you know what your doing, you can turn the head into a pretty free flowin deal......and you come out under 8k..
 

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Discussion Starter #13
I looked at a site someone linked to on here that has cnc'd heads. They're claiming 180-something cfm after their $1200 port job. To be fair, I think that includes reworking the head completely with new springs, guides, and valves. The indy aluminum one is supposed to be 300 cfm out of the box. I don't think it's possible to get a stock head within 100 cfm of that. I might be wrong about that, but I can't recall ever having seen flowbench results of any 12v head as high as 200 cfm.
 

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Ya, not saying it doesnt exist, but I've never seen a stock head flow over 200cfm....I've also not spent alot looking for one.
 

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Discussion Starter #15
Yep, if the aftermarket will release a decent flowing head that people can afford, we'll see a new level of power out of these engines.
 

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well there had to be something to limit them, hahaha or the CR guys wouldnt be able to have any fun!! A pump that can flow 500cc's without thinkin twice, bottom end will hold 1000hp, stout blocks, its actually a miracle that these things dont breathe....I would have probably already wrecked mine. Back to somewhat on topic though, just puttin time in the stocker makes a huge difference. If you ever get your head off, just start lookin around it and you'll see.
 

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Discussion Starter #17
You may have been joking, but you really hit it on the head.

well there had to be something to limit them, hahaha or the CR guys wouldnt be able to have any fun!! A pump that can flow 500cc's without thinkin twice, bottom end will hold 1000hp, stout blocks, its actually a miracle that these things dont breathe....I would have probably already wrecked mine. Back to somewhat on topic though, just puttin time in the stocker makes a huge difference. If you ever get your head off, just start lookin around it and you'll see.
 

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I looked at a site someone linked to on here that has cnc'd heads. They're claiming 180-something cfm after their $1200 port job. To be fair, I think that includes reworking the head completely with new springs, guides, and valves. The indy aluminum one is supposed to be 300 cfm out of the box. I don't think it's possible to get a stock head within 100 cfm of that. I might be wrong about that, but I can't recall ever having seen flowbench results of any 12v head as high as 200 cfm.
There are cheaper places to get that work done (Pure Diesel Power). I a nicely work over 12v head can do 250cfm. I can tell you, a highly ported head is the best money you can spend, you'd be amazed at the spool-up and the low RPM boost I can build with my big set of twins.
 

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well there had to be something to limit them, hahaha or the CR guys wouldnt be able to have any fun!! A pump that can flow 500cc's without thinkin twice, bottom end will hold 1000hp, stout blocks, its actually a miracle that these things dont breathe....I would have probably already wrecked mine. Back to somewhat on topic though, just puttin time in the stocker makes a huge difference. If you ever get your head off, just start lookin around it and you'll see.
Id take a 12v head over a CR head any day of the week.
 

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I didnt think they were bad at all......keep in mind I dont mess with CR at all.
 
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