Upgrading Power on 5.7 300hp

[Tail_Gunner]

Re: Upgrading Power on 5.7 300hp

No there are not multiple tables in in our marine efi system's...it's pretty much set it and forget it. That is the timing tune or curve is preset and locked in stone the curves remain constant....unless it experience's detonation that is...The preset tables advance or retard timing based or rpm...and some temp levels.

There is no need for changing the base fuel maps the system cannot read afr's....The auto tune in the CMD system does use OS sensor's so it can adjust fuel pulse on the fly..... however OS sensor fry when exposed to a wet exhasut system...think like this.... they reach 700 degree's they get wet...... and bang....even steam cracks them.

 

[Scott Danforth]

Re: Upgrading Power on 5.7 300hp

The fuel map and timing map has columns for map sensor data and rows for RPM. there is only one fuel map, and one timing map. timing signal (EST) varies by MAP (load), RPM and knock sensor trim

No there are not multiple tables in in our marine efi system's...it's pretty much set it and forget it. That is the timing is preset and locked in stone the curves remain constant....unless it experience's detonation that is...

and then the timing map is trimmed by the knock sensor.

 

[Tail_Gunner]

Re: Upgrading Power on 5.7 300hp

The fuel map and timing map has columns for map sensor data and rows for RPM. there is only one fuel map, and one timing map. timing signal (EST) varies by MAP (load), RPM and knock sensor trim



and then the timing map is trimmed by the knock sensor.

Well articulated nicely trimmed....trimmed... i like that.:lol:

 

[Walt T]

Re: Upgrading Power on 5.7 300hp

I once knew a blonde who was nicely trimmed. Wasn't too articulate though. I didn't care.

 

[Naf]

Re: Upgrading Power on 5.7 300hp

FYI, Our cam for the 5.7 300hp is

196 / 206 with .460 / .481, with 1.6 rockers, and a LSA of 109. Its the HT383 cam from Gm.

I will be replacing this cam with the LT4 Hot-cam, which has 219 / 228 .525 / .525, with 1.6 rockers, and a LSA od 112.

Researching it shows that this is a very acceptable marine cam for our VP. Should give me great bottom end torque and enough power to take me over 50mph. I will also be installin the Ls9 beehive springs for up to .550 lift, with Ti retainers and GMPP HOT CAM roller rocker arms, and Comp cam pushrods.

Its a proven cam, and everyone that installed it loves the cam. Dennis Moore mentions it in his small block marine book as well...So its a winner for me. Just search offshoreonly for the results

 

[Walt T]

Re: Upgrading Power on 5.7 300hp

It would be if you can get rpms up high enough to use it. Its a 6000 rpm cam and kind of a one size fits all. Not dissing the cam, it is a good solid performer and its very popular. I'm trying to figure out where it fits in your build and how the ecm is gonna fuel it but hey I'm not building it and I haven't done the research you have. I wouldn't pick that particular camshaft. That's my opinion and I'm stickin to it.