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Discussion Starter #1
I have to pull my heads here in a few days (blown head gasket) and I am going to get them rebuilt. I want to put a better cam in and was wondering what you guys would recommend. Im not wanting anything crazy this truck is driven every day.

I have a early 99 with stage 2 single shot (I am going to replace them also) a dominator D66 turbo, a rebuilt transmission. with 250,000 miles

thanks in advance
 

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Stuck in Commiefornia...
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Ok, there is really little to no need to do a cam swap on a daily driver. Unless you are looking for a specific change in power delivery, either lower rpm torque delivery or higher rpm horsepower, the cam isn't really something you want to change. Turbo diesels are not like gas engines where a camshaft can make a significant and appreciable improvement. You can add more lift and hold the intake valve open longer, but you don't want more overlap, and you really don't want the exhaust opening too soon.

If you have larger injectors , you may benefit slightly from additional airflow filling the cylinder, but at the same time, you'll need the larger turbo to support the new airflow demands anyway. Your best bet would be to use the money you'll spend on a cam and related parts to upgrade your early 99 to late 99 spec and run a GTP38R. With the larger bellowed up pipes and turbo, you should realize EGT reductions and drive pressure should be lower. Then with the larger plenums and spider you will see cooler intake temps and a slightly lower boost number, but you'll have more air flowing into the head.

As far as injectors, Stage 2 is a generic marketing term. What size are they? For a daily driver a 175cc/80% or a 200cc/100% single shot would be spot on with a 38R. After all of the research I've done on the subject, I wouldn't waste my money on anything smaller than a 160cc/80%. The ability to deliver the fuel in the same or slightly less time than a stock injector will help EGT and power
 

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Discussion Starter #3
Okay so I was wrong I have 160 cc Single Shots injectors and I am going to get new ones before the truck gets put back together. my turbo is a Bean's Diesel Performance D66 and to my understanding is real close to a 38r. I agree about no cam change however I am now thinking about replacing lifters.

any help on thing i might want to change or replace while the motor is out would be great.
 

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Okay so I was wrong I have 160 cc Single Shots injectors and I am going to get new ones before the truck gets put back together. my turbo is a Bean's Diesel Performance D66 and to my understanding is real close to a 38r. I agree about no cam change however I am now thinking about replacing lifters.

any help on thing i might want to change or replace while the motor is out would be great.
Expect the unexpected once you tear into it. You may or may not find any surprises...hopefully not, and all goes as well as can be expected.

New lifters work best with a new cam and lifter guides.

Harry
 

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Stuck in Commiefornia...
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The only issue with a D66 is the added mass of the larger compressor wheel results in more force required from the turbine section to spin it, and that means a higher drive pressure to drive it. The 38R is ball bearing, so it takes less energy to spool compared to the cartridge bearing you have now.

If you are going to change injectors I've recently done extensive research on this planning my own mods, I would look seriously at a 175/80, or if you want to stick with the same size go to a 160/30 or even 160/80. The ability to inject the fuel in a shorter period of time with a larger nozzle means you can run slightly less timing and finish the injection earlier, valuable for keeping EGTs and cylinder pressures in check. This will be especially helpful with a D66.

As for lifters, unless you suspect an issue, I would not change them. You have set wear patterns on the cam lobes and rollers, on the lifters and lifter bores and guides. If you suspect a sticking lifter, I'd strongly suggest Archoil AR9100, if not permanently, at least for two oil changes, it has a tremendous cleansing effect as well as it's lubrication benefits. I'm running it in my E99 right now, having seen the cleaning benefits in my 6.0L between tear downs.
 
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