Changing 12v injector tips?

Here's a run down of the build. At least what I remember.

o-ringed and mild port head
#60 valve springs
hardened retainers and locks
head studs
5X16 injectors
Max Spool 2.5 cam
new tappets
adjustable pump gear
full cut dv's and modded holders
zero fule plate
5K GSK
Fuelab pump
65mm or 70mm S400
PDI T4 exhaust manifold
bolt in rear freeze plug w/bypass
SB clutch
 
mech2161 said:
Here's a run down of the build. At least what I remember.

o-ringed and mild port head
#60 valve springs
hardened retainers and locks
head studs
5X16 injectors
Max Spool 2.5 cam
new tappets
adjustable pump gear
full cut dv's and modded holders
zero fule plate
5K GSK
Fuelab pump
65mm or 70mm S400
PDI T4 exhaust manifold
bolt in rear freeze plug w/bypass
SB clutch
Click to expand...

Only thing I don't like is the 60# valve springs. If you plan on 4k+, get some 110# Hamiltons in there.
 
Hmmm I've not had anyone else say they weren't enough. I'll look into this.
 
Kevin, here is a direct quote from Zach Hamilton.

The 60# springs typically end up around 150lbs +/- 5lbs. The 60lb. rating is a measure of how much back pressure the spring can control. These springs are used in engines that have exhaust brakes, where the back pressure is much greater than factory. You might ask, if they are fine to 60 lbs why do I need any better? Pressure X Surface area= force. The intake of the 12v is larger so it can only effectively control around 35psi of pressure on the valve face. This problem is greatly intensified as pressure and RPMs increase or if a larger valve is being used. Over 3800 rpm and 35lbs of boost the valve IS NOT being controled properly in a 12v, even with 60lb ers. The gram weight per lb. of spring pressure of the valve train in a 24v with stock springs is similar to the mass of the 12v valve train with 60lb springs. Around 3800 rpm the 24v valve train becomes unstable, this is because there is not enough spring pressure to control the mass in motion. One edge that the 24v has over the 12v is that it has less surface area on the face of the valve so it typically can handle around 50psi before better springs are necessary. If you are over 50psi and over 3800rpm with your 24v, you need springs! I have seen people run fine to 4500rpm plus on 24v engines without failures but there was definately valve float. I hear a lot of people say that seat pressure is irrelevant. But when boost pressures are over 50lbs, it is a major part of the equation. If your intake or exhaust opens before the cam tells it to, Engine efficiency is greatly diminished!

I copied that quote from this thread. 110# spring sale - Competition Diesel.Com - Bringing The BEST Together

Just trying to help you kick my azz without breaking. LOL
 
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