Reaching for 600hp but cant get there...help

[strokinKR]

I vote not maintaining rail pressure.

 

[madman1234509]

I wouldnt be surprised.... Many 6.4s, esp ones with moderate or high mileage on them wont maintain rp with a full out race tune. It could also be the transmission, or even a boost leak by the sounds of it, its hard to say. Wouldnt hurt to do a leak test.

 

[Crack85]

Cant find it on their site, but a loss of 9hp, gain of 23ftlbs

http://powerstrokearmy.com/forums/showthread.php?t=23555&showall=1

post#669

Thanks sir.

 

[Jeff@Spartan]

Rail pressure is holding as well.

What is rail pressure maintaining at?

 

[madman1234509]

Thanks sir.

Hey, no problem!

 

[MaineiacF250]

I just went out and did a half a dozen WOT runs and the lowest rail pressure I saw was 24780 at WOT for good 1/4 mile and would build to 54-55lbs of boost

 

[jdgleason]

You could still have a boost leak. What were egts?

 

[MaineiacF250]

egts were 1300-1400

 

[08BIGRIG]

When did you purchase your steed speed manifolds? I have tested them the first go around and my truck lost a bunch of power as well as torque. If you have the first set of these, I have no doubt that is the issue.

 

[B585Ford]

no TC slip noticed and will do a boost leak test later in the week. I appreciate all the help

If you have a DD, you can monitor TC slip. With that big of tires and a stock tranny I would think that could be an issue (along with a leak).

 

[MaineiacF250]

I purchased the manifolds in December from Rudys

 

[MaineiacF250]

Also I will look into the TC slip and leak later in the week. Thanks again eveyone

 

[08BIGRIG]

I purchased the manifolds in December from Rudys

I am willing to bet that this is your issue. I bet if you ditch the steed speeds and went either back to stock or with 6.0 manifolds and custom up pipes you will see a good increase. I was down this same road last winter.

 

[bigrpowr]

I am willing to bet that this is your issue. I bet if you ditch the steed speeds and went either back to stock or with 6.0 manifolds and custom up pipes you will see a good increase. I was down this same road last winter.

i recall hearing something about this steed speed issue.

 

[madman1234509]

If you dont find anything boost leak wise or transmission wise I wouldnt hesitate to sell your up pipes andmanis and get stock, or 6.0 manifolds

 

[B585Ford]

i recall hearing something about this steed speed issue.


LOL
Cant believe you heard about it

 

[08SUPERKING]

Was it not said they would replace them for the ones sold before the v2 came out...

 

[08BIGRIG]

Was it not said they would replace them for the ones sold before the v2 came out...

If it was, you still need to get new up pipes because the flange will be different from the old steed speed to the new ones. Personally, I would ditch them all together and go back with stockers or the 6.0 manifolds and up pipes.

 

[08BIGRIG]

i recall hearing something about this steed speed issue.

:toast:

 

[ncollins64]

Not to derail but what about the RCD manifolds? Has anybody ran them with gains?