which cummins turbo

[FordGuy100]

The RPM at which the turbo comes into play is directly related to the size of the exhaust housing, which are easily switchable on the Cummins/Holset turbos.

Stock 1st Gen. Cummins are 18cc, later I/C 1st Gen. are 21cc, common replacements are 12cc, 14cc, and 16cc.

The smaller the exhaust housing, the lower RPM the turbo will spool up.

A trade off is, the smaller the exhaust housing, the higher the relative EGTs, especially when under load.


One missing link in the non-turbo engines, once a turbo is installed, is the lack of an AFC housing on the injection-pump.

The injection-pump on the Cummins engine has an AFC housing that is connected to the intake manifold via a boost line.

The AFC senses the increase in boost pressure and increases fueling accordingly.

Without the AFC, most of the dramatic quick gains of a turbo are lost.

Umm...I can live without the AFC thank you. I've driven a 12 valve before and its kinda annoying having to live with that dang AFC, you cant go WOT from a low RPM cause you have no boost. Maybe its just me, but I perfer not to have them.

 

[MIDNIGHT RIDER]

Umm...I can live without the AFC thank you. I've driven a 12 valve before and its kinda annoying having to live with that dang AFC, you cant go WOT from a low RPM cause you have no boost. Maybe its just me, but I perfer not to have them.

The one you drove must have been way out of adjustment.

The AFC dramatically increases fueling with increase in boost and has absolutely no effect on normal pump fueling whatsoever.

 

[tractorman86]

i can live without it for $285!! that's rediculous, and it isn't even a true AFC, it is a smoke limiter, meaning it holds fuel back till the boost comes up we would want the opposite.

 

[redneckaggie]

My turbo will be slightly higher than the injector pump timing cover on the front of the engine so it should work. Im goin to run my rdt from the valley pan grommet. I agree with midnight fordguy. My bro has owned two of the older twelve valve cummins and they are almost instantaneous on spool up and we would make the 35 in mudders on the back scream in 3rd gear. My bro also had that pump tweaked out of its mind. It would spank stock mustang gts and most of the ricer racers around here. needless to say not many people will rev up beside it. Im still tryin to find one of the holsets because i don't want to spend all my money on this turbo install. I already have a rajay turbo that will get bolted to it for now and if the holset has to wait it will just wait, the truck aint goin nowhere.