J code vs C code. where does the extra 30 hp come from?

[desertrat67]

Does the intake make that much difference or is there something else in there also? I could use a few more HP and if the intake alone doesthis, I think it would be worth it.

 

[AJMBLAZER]

Sounds to me like the EGR is a big factor in this. Not sure either.

Although I wonder about the 30hp number, even though I've used it before. That's the official difference between the C and J code engines but there's head differences as well. Dunno if the pistons are the same either.
At the very least the intake is better for simplifying things and giving you a decent bump in power.

 

[fallout232]

Higher Output Injection pump, More Air from Intake manifold, Different Injection Precups in the heads and No EGR, Everything else is virtually indentical. 70-80 percent of the 30 hp comes from the turned up injection pump and precups. (You can turn up a C Code pump just not as much)

 

[desertrat67]

I was unaware of there being different IPs.

 

[Wrench]

Yep, several different IP's but as far as I know you can turn them all up farther than a N/A 6.2 will burn. That's the biggest difference. I'm not even sure there were different pre-cups between the C- and J- code engines. IP calibration and EGR were the primary differences. EGR is probably responsible for about 5 of those HP, but the open intake will let you turn the pump up more as well . . .

 

[desertrat67]

Now are the differences between the dual plane and single pplane J codes? Or C codes for that matter?

 

[Wrench]

The C code intake has the EGR tube up the middle, which is much more restrictive even if you remove all the egr crap.

I can't see there being much difference between the single and dual plane J code intakes, but the 6.5TD non-egr intakes are all single plane . . .

 

[desertrat67]

Learning more every day.