Help Cam Tuning a Cobra Jet Manifold on a 2016 GT.

[veeefour]

IMRC 100% stock, ton of changes to VCT not only in OP mode. For CJ mani you have to adjust VCT mapped points. It needs a complete make over with cams.

[Bill88stang]

wasn't aware you could leave the stock settings along on the imrc including in the config screen just leaking them closed at 0-13 and open 14-26. learn something new every day. I would think I don't need that much changes going to a 18 manifold locked out though correct?

[Bill88stang]

you guys leaving on cylair anticipation on ?

[veeefour]

2018 mani only needs a few cosmetic changes.

You should switch the cylair anticipation off only for MAF tuning.

[Bill88stang]

Looks like I have a few different ways to try to make this work using all mapped points it seems to me to drive better if I can just get the cams dialed in I think it will be 100 percent. ill also try it your way veefour leaving the imrc 100% stock settings including the settings in the config table leaving them in the closed postion in 0-13 and open in 14-26 correct?

[LightingBlue17]

Now with leaving the IMRC etting untouched will you still have to select disabled in the tune for IMRC if locked out?

Then by VCT tuning you're referring to just updating the mapped point VCT tables where at say at IVO 20 and EVC 0 you use mapped point 0 and so on and just go through all the 26 mapped point call outs and do this?

What confuses me with VCT tuning is you have different cam angles called out for different mapped points. Then you also have OP specific for VCT and rpm and load.

I am new and just trying to get a better understanding on how it talks to everything. About to swap my ported 18 manifold on my 2017 with lock outs.

[paulsmithsr]

FYI. I dont tune the Cobra jet that way —- I tune the imrc and ivo and Evc —- My car runs like stock. Just way faster

[paulsmithsr]

Imrc are for long runner and then short blocked for swirel
runners —- cobra jet has only short aka high RPM

[K44]

Imrc are for long runner and then short
runners —- cobra jet has only short aka high RPM

Have you looked inside a manifold with IMRC? The runners stay the same length all the IMRC does is restrict flow. This causes turbulence in the combustion chamber to stabilize the flame front.

I wish Ford made a variable length runner manifold.

[veeefour]

Imrc are for long runner and then short blocked for swirel
runners —- cobra jet has only short aka high RPM

Has nothing to do with runner length - it restricts port cross section by ~75% thus reducing efficiency.

[veeefour]

Have you looked inside a manifold with IMRC? The runners stay the same length all the IMRC does is restrict flow. This causes turbulence in the combustion chamber to stabilize the flame front.

I wish Ford made a variable length runner manifold.

Just like yamaha with YCCI, would be great...was thinking about doing this on my own some time ago.
https://youtu.be/RBQCus9Ifx0