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SpeedySpeedBoy313
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52 Posts
Discussion Starter · #1 ·
I've waited a long time for this. So I just bought some "Stage 2" cams for my 2.5 mazda 3 without really thinking about the repercussions (even though I knew there would be). Am I going to need larger injectors and/or a bigger fuel pump? I'm running E85 now, and as we all know E85 eats a lot more fuel than petrol does, and now it will be even more fuel hungry with these cams. Will the tranny handle it? Either way, I'm going to dyno the car before the cams and after the cams on E85 and see what kind of power she can make. I really want to know what I made over stock but I don't have the time/money to remove all the mods I have made and reinstall them. If I was willing to do this, I feel like I would be cheating myself since the before/after dyno would be on different days, different temps, all variables would be different. Maybe I'm overthinking this but when taking quantitative measurements I would like to be as accurate and precise as possible. Maybe this will turn into a sort of build thread with the cams being the most major mod.

TLDR; I purchased intake and exhaust cams for my 2015 2.5L Mazda 3 and will dyno before and after to see how much money I wasted on some HP.
 

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You'll need new springs at least, and a retune. Then you'll know for sure if you need bigger injectors.
 

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SpeedySpeedBoy313
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52 Posts
Discussion Starter · #3 ·
You'll need new springs at least, and a retune. Then you'll know for sure if you need bigger injectors.
I figured I would need a retune, but I didn't think i needed new springs. I thought I remember reading on the cams description that it said "for use with stock springs". I very well could be mistaken so I will check with Matt.
 

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Stage I cams from OVT use the stock springs, and focus on mainly mid-range improvement, while stage II cams are designed for maximum lift/ mainly top-end power, and require aftermarket springs that you will get from OVT. You won't need to change the fuel system, as the skyactiv HPFP & injectors can output much more fuel than required for a stock car (that is why the 2.0 skyactiv fuel pump was sufficient to provide enough fuel for a turbo setup making 260 whp on E85). The stock manual transmission is also plenty strong, especially if you shift smoothly. Generally, its going to be enough if you are staying in NA.
 

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What ever happened to this?
Maybe it was figured out ...... not the best information/ideas/suggestion etc., about the cams... :wink2:
Cams (specifically their specifications) are one of the parts for decades that gets talked about so much but really very few know and truly understand about them.

One thing I often get a kick out of seeing the usage of the word "STAGE". This has always been an advertising ploy to make parts either from the OEM or from aftermarket sound more impressive. Often things that are categorized in a alphabetical or numerical order most tend to think the higher in each catagory denotes more.:laugh2:
 

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What ever happened to this?
The OP hasn't come back here to update so there is no way to say what the outcome was.

One thing I often get a kick out of seeing the usage of the word "STAGE". This has always been an advertising ploy to make parts either from the OEM or from aftermarket sound more impressive. Often things that are categorized in a alphabetical or numerical order most tend to think the higher in each catagory denotes more.:laugh2:
I'm pretty sure the specs and requirements were listed in the description so you knew what you were getting, or should have anyhow. Thats what they were called because there had to be some sort of differentiation between the two when placing an order. He could have named them Bob and George, it makes little difference as long as you got the part you wanted......:smile2: Also, in this case, Stage 2 does denote more - more work, more hassles, more time and money to make it work. Not necessarily more usable power.:frown2:
 

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Stage 2 = 3/4 Race
Stage 3 = Full Race

:blink::blink::blink:
 
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