Cam question

[f.creek-ranch]

Im not confirm in cams....
The new 6.4 cam is ICL 108 LSA 120,5 215/221@050
the old 5.7 cam is ICL 103 LSA 115 186/208@050

to get the 6.4 working like the 5.7 at same icl, do I have to subtract the 5 degrees in WOT exhaust cam position table ?

[f.creek-ranch]

1DEB4BE1-A307-4E6A-9581-71044EF2C086.pngBE2EFAF8-7596-4715-B9C9-37BF74D942C5.png

[Hemituna]

Good job on using a cam calculator. Makes this a little easier to get your head around

If you advance each cam on the calculator until it has the same ICL as your specs, you will have your starting points.
This is where the cam physically sits at full advance (idle). The ECL of the original cam is the number the 5.7 PCM uses at full advance.

The difference between both cams ECL number at full advance is the offset you will need to use when you have decided where you want the 6.4 cam to be.
(5.7 will be 127 approx and 6.4 will be 133 approx at full adv.) So a 6 degree offset in this example. You need to take 6 degs off the 6.4's actual ECL to use in the 5.7's exhaust table
(or in reverse, add 6 degs to 5.7 table numbers to calc where 6.4 cam actually is)

Note these numbers while checking out the valve events. (IO, IC, EO, EC). Move the old cam around using the original exhaust position table.
Try same table on new cam (using offset ). You will see the events are way different due to duration, but also LSA.
Full advance position is 5 degs more retarded ICL on new cam vs old. But the ECL is more advanced at same position because of bigger LSA.

So to answer your original question about getting 6.4 cam to work at same ICL as 5.7, you will see that it is not that simple.
You cant get as much ICL advance, but at the same time ECL is way different also.
So move cam around on the calculator until the valve events are where you desire.
When you get it where you want, use the ECL (with offset) in your Exhaust Cam table.

Easy

[PurpleRam]

it's tough , because both "programs" use different events , and the truck programs are different yet. lots of try and try again.

[PurpleRam]

take a read thru this thread might help .....

https://forum.hptuners.com/showthrea...-6-2-cam/page2

[f.creek-ranch]

IMG_5546.jpg

Seems the problem with low rpm power maybe the intake timing.

6.4 cam opens a little later the intake, exhaust specs are closer to 5.7.

Is this correct ?

[Hemituna]

That is why you need to look at the valve events. It all gets so much clearer...
Yes, the intake opens later, exhaust opens earlier....Big LSA reduces overlap for a bigger duration cam, makes it cleaner for emissions,
but will make it lazier at low rpm...it works well on the bigger displacement, higher comp 6.4 that it came from.
Unless you are adding a blower to the 5.7. a lower LSA might be better.

[f.creek-ranch]

OK, Thanks.
It looks a lot clearer to me with this information.
I set the cam to open the Intake a little bit later.
Seems to work good.
The most power gain is at high rpm, that's the reason for changing it.
6500 rpm instead of 5700 is a good number.
With lower gears and light nitro shot I get where I want....