Diesel87

I just recently bought a MP8. When I went for a test drive I could not tell a difference at all. The only thing that happened was my RP gauge would go up as I turned the dial. I could not tell the truck had anymore power at all. I know the MP8s job is to increase RP but I was expecting a little more power or at least quicker spool up but nothing. Any suggestions or comments?

SpeedyWS6

Put it on the dyno. You will probably find that anything past 70% on the dial is a waste but you will probably be surprised how much it really helps from 50-70%.

I never understand why people trust the butt dyno... I know mine doesn't work well at all.

J-man

Anything that is truly adding 50 + hp is very noticeable on the butt dyno! I had the edge juice with attitude that you can adjust on the fly, the power increments are about 20 hp per level ( 1- 20, 2- 40, 3-60, 4-80, 5-100) I could easily tell each level change. The mp-8 is supposed to add 100 hp at the highest setting also, so if you can't feel it, something is very wrong!

SpeedyWS6

The more power something makes the less noticeable changes are going to be. Take a 300hp truck and add 50 horse and it's a big difference. Take a 600hp truck and add 50 horse and it may be hard to tell.

From his sig he has a pretty well modded truck. So he wouldn't get a true 100 horses from it anyway.

You have to remember that it is rated at 100 horse gain on a near stock truck. Some of the power is gained from boost fooling (on a stock truck) and that isn't going to do him anything cause he has a boost fooler and twins already.

Dodgezilla

I think SpeedyWS6 is right on this one. That MP8 is not gonna give an additional 100hp when you add it with all those other mods. What you may feel is a bit better off the line performance but if you are looking for some top end performance then you will have to put the truck on the dyno. I bet you will see an increase there when you turn the MP8 on....

Pliny the Elder

IMO, dont run the MP8 on the street its for dyno/sled/drag racing ONLY, the pressure spikes along with the raised rail PSI, is one of the major causes to a lot of melted cummins, especially on an 06 which runs to much rail psi from the factory as it is.

Diesel87

I don't plan to run it on the street, I have no reason to. I wasn't expecting a big hp gain but I was expecting better throttle response. I have read a ton of posts on here about how great the smarty and ts are together, but I really regret buying it. Hopefully the dyno will prove me wrong. I think i would notice it more if I had a stock cp3, because my modded cp3 has no problem keeping the rail pressure up.

jwb600

ive seen dyno numbers recently that went up by 70 rwhp on a built truck. they can help with the right setup. but I will also agree with the statement dont run it much big rail pressure is hard on everything

Asher

What are you running the FP setting on the smarty at? If you have it turned up, you might already be maxing out. Maybe turn the FP setting on the smarty down and then try out the MP-8, if you still don't feel the difference then you have a bad box.

Diesel87

I have the smarty RP at stock. I know the box is good because I can watch my Rail pressure go up on my gauge when I turn the dial. With the dial turned up I can get 26,000 psi. I don't want anymore than that.

SINGLESTACK

I made 555hp with the smarty alone and then turned the mp-8 on 50% and it went up to 570 something, and it was coming on hard and then ran the rail dry at 2400 some rpm so I know theres more to get out of it. I have a stock cp3.

KelschKid

My Smarty MP-8 stack hasn't impressed me very much either, but I can tell that it is giving power. Every truck is different so perhaps it's working well on some trucks, and not so well on others.

my .02

ahuskins1988

mp8 boosts hard on my truck and i also get better fuel milage (staying out of it) but it is very noticable on the different settings i agree with above dude ur all modded up and this box may not support your other mods

dodgediesel

The one I just sold was a major difference on a more stock truck. When highly modded, I couldn't feel the same difference as when my truck was more stock. (if that made any sense...)