Bosch p7100 0 402 746 642. Help me move the rack forward more or advice please

[dds92780]

Okay so the story is that i had a s300 turbo on my mack e7350 mechanical and i went up to 20 percent oversized injectors and had a pump guy turn up the pump. I made good power and kept fuel economy descent but i wanted to complete the setup by getting a bigger 427 turbo. I put it on with my same fuel settings and i felt i lost a lil power but still not a slow truck. I then wen

I need help from anyone that has moved the rack forward on this bosch pump of mine. pump number is a 0 402 746 642

I need to learn how to move the rack forward or backward in case i want to get a smaller turbo housing. Is it as simple as taking the top cover and side cover off and just trying to turn a screw or socket to move the rack forward?

I edited the post. It turns out i am maxed out on my pump right now.

[dds92780]

Looks like i need the 0 402 746 852 pump that came out of a 400hp mack. My pump guy says ill be tickled to death with how much better we can make it.

I'm gonna have to make some calls and see how much i can get a core for. Its a 19 degrees of timing pump and my pump right now is 11.5 degrees.

He said I have a very strong motor being the e7 and that i will just fine with this turbo and injection pump setup. I would like others to chime in though and see what they think.

So right now im running 20 percent oversized injectors, a 427-460 turbo and the rack moved all the way forward. Its quick yes, but i think the other pump will allow us to flow match it all and still be healthy.

I'm going to drive it a few weeks and try to take it easy and see if the combo i got now still allows more power with less pedal and increased mpg.

[theakerstwo]

What does your exhaust temp run and how much boost are you running?If you don't have thoses gauges in it don't play with your engine any more.You now have enough fuel to it to damage the engine if your not carefull.

[dds92780]

My boost gets up to 35. My exhaust temp never goes higher than 850

Turns out my rack is all the way forward on this setup. (yikes)

Still shocked how good its running though

My pump guy says the next best thing to do is to get a 400 hp mack mechanical pump and its got better parts in it to make more power and then have it flow matched to my turbo

Am i best off just going with a smaller turbo??

He says that he has put a bigger turbo and injectors with this pump on a few trucks and the guys loved it

My only concern is that the current pump im using was 11.5 degrees timing and the 400 hp one is 19 degrees timing

He does make a good point though. on my current pump all we kept doing was moving the rack forward, on the new pump we can fine tune it on guess once its off the truck

What is the difference between those two pumps to where i should make a switch???