Tuning for bigger cams

Discussion of tuning specific to MAZDASPEED3/MAZDASPEED Axela/Mazda 3 MPS vehicles
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Joined: November 6th, 2019, 8:40 am

Re: Tuning for bigger cams

Post by eli777 »

Hey man!
Can i ask you a question, how has been your experience with these cs cams? did turbo spooling improved? did you notice a performance difference and improvement in throttle response, hp and tq?
i will be doing upgrade from k04 to cs turbo cst4, 3.5 htp intake and cs cams on my stock engine. I have to do timing chain so ive decided to do cams but i wanted to know from your experience if these cams helped improved your spooling time. The reason of my question is because i was reading that cams on turbo cars shouldn’t have to much overlap because supposely that affects spooling time but you tell me if this has been your case with cs cams or is this not true with these cs cams?
Will it actually help me when upgrading my turbo? Please can you kindly share your experience with me, because locally there is nobody that can tell me much about them. Thanks guy in advance for your support.

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Re: Tuning for bigger cams

Post by mituc »

So I'll post here my response to you on MSF, maybe it will help others.

While you were sending me this message I just fixed an issue that I had since rebuilt the engine at the end of Sep so now I can report back.
I can't tell much about the improved spool because I also moved from a 3071R gen1 to a 3071R gen2. Going WOT at 2000rpm (yes, just for fun) puts the car into boost less than 1s and 200rpm later. Not crazy boost but enough to get it moving at a decent pace. That is mostly the merit of the turbo though because at such low RPM you can also benefit from the intake cam advance, so the higher lift will count but not that much like in the higher rev range.

What I can tell you for sure changed is the choking of the whole system in the top end of the rev range. Past 6200rpm I could feel the engine kind of plateaus but now it pulls constantly past 7krpm.

I recommend using the Crower springs instead of the Supertech which are not a real upgrade from stock unless you're going for the double spring version which will increase heat quite a lot in the head, so may not be street friendly. It may be ok if you're only using the car for drag, but circuit/street racing - not sure.
I did some research on the springs but do not take my word for it, even if I'm at the second set of these springs (the 1st one was in the damaged engine). You should check with your tuner as well, just to be sure.
New OEM valve springs may serve you well, however. Even your current ones if they're fresh.

The thing with these CS cams is that they're not very different from the OEMs, they just lift more so allow for more air to be drawn in. This makes tuning less complicated, you basically can run these with your current tune and only observe the improvements.
One other thing that I noticed and I love a lot is that they made the engine quieter which is a huge plus when running 3" exhaust. The cops will turn their heads around only to look at the rims, not because they're woken up by the exhaust drone.

I totally recommend them if you are willing to get them. Good luck and let me know if you have any other questions!
2008 Cosmic Blue Mazda 3MPS
Build engine + WMI + GTX3071, ~476WHP @31-32PSI
2008 Icy Blue Mazda CX7
Stock engine and exhaust (YES!!), JBR3" + GTX2867 gen2 + Autotech HPFP, self-tuned to 320-ish BHP

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