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Has anyone replaced the cams in their 3's? Did you also replace the valves and the lifters? I'm hoping to do this to my 2.5, probably after the warranty expires but until then I will thoroughly research. Do any of you have the OV Cams? What kinda HP gains did you get with or without tune


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*The Electrician*
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here we go again.......guess i better make popcorn now :popcorn:
@arathol thx dood
 

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Has anyone replaced the cams in their 3's? Did you also replace the valves and the lifters? I'm hoping to do this to my 2.5, probably after the warranty expires but until then I will thoroughly research. Do any of you have the OV Cams? What kinda HP gains did you get with or without tune


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I have the OVT Stage 1 Exhaust cam on my 2.0. You do not need to replace the valves, lifters, or springs for their stage 1 cams. All stock parts are fine considering that the cams were designed to work with them, and the improvement in lift does not exceed the capacity of the springs. Stage 2 you will need new springs from what I understand. I recommend getting this installed professionally, and make sure you have the mechanic completely remove the timing chain/side engine cover rather than try to take off the chain and swap cams like the shop manual may suggest. There are marks on the chain gears and chain which need to line up exactly, and the safest way to do this is by having the engine side cover and timing chain fully off. It becomes very difficult to disengage the chain tensioner without taking the cover off, and when the first gear comes off the chain, the others will turn under tension. If you turn the cams too far while the crank is at or near TDC, you will bend the valves which causes a world of trouble (and put a huge dent in your wallet). Here is a video showing how to align the gears with the timing chain:



As far as gains go, I noticed a bump in torque mainly from around 3500-5500 rpm with just the stage 1 exhaust cam. The peak lift is only slightly improved to match the stock springs, so the improvement is mainly in duration which improved mid-range and smoothed top-end. You won't see big top-end gains unless you get the stage 2 larger lift & upgraded springs package. An aftermarket header would help, especially in my case, but there are no good options for me. There was no loss in low-end on my setup. I have a crappy 2nd gen 4-1 header which limits what I could get out of it, but I am seeing 10-15 ft/lbs tq improvement in the mid range which I can really feel (More when intake air temperatures get colder in the winter). The torque curve is flatter from 3500-5000 rpm. The only downside is a bit of valve chatter from the valves hitting the stock lifters which you can hear from idle till around 2300 rpm (slight ticking). Its not too bad though, an easily gets drowned out by my cat-back or the AC fan on level 2. The cams aren't going to damage the lifters based on their mild profile.
 

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I have the OVT Stage 1 Exhaust cam on my 2.0. You do not need to replace the valves, lifters, or springs for their stage 1 cams. All stock parts are fine considering that the cams were designed to work with them, and the improvement in lift does not exceed the capacity of the springs. Stage 2 you will need new springs from what I understand. I recommend getting this installed professionally, and make sure you have the mechanic completely remove the timing chain/side engine cover rather than try to take off the chain and swap cams like the shop manual may suggest. There are marks on the chain gears and chain which need to line up exactly, and the safest way to do this is by having the engine side cover and timing chain fully off. It becomes very difficult to disengage the chain tensioner without taking the cover off, and when the first gear comes off the chain, the others will turn under tension. If you turn the cams too far while the crank is at or near TDC, you will bend the valves which causes a world of trouble (and put a huge dent in your wallet). Here is a video showing how to align the gears with the timing chain:

https://www.youtube.com/watch?v=Tvk61nroQxs


As far as gains go, I noticed a bump in torque mainly from around 3500-5500 rpm with just the stage 1 exhaust cam. The peak lift is only slightly improved to match the stock springs, so the improvement is mainly in duration which improved mid-range and smoothed top-end. You won't see big top-end gains unless you get the stage 2 larger lift & upgraded springs package. An aftermarket header would help, especially in my case, but there are no good options for me. There was no loss in low-end on my setup. I have a crappy 2nd gen 4-1 header which limits what I could get out of it, but I am seeing 10-15 ft/lbs tq improvement in the mid range which I can really feel (More when intake air temperatures get colder in the winter). The torque curve is flatter from 3500-5000 rpm. The only downside is a bit of valve chatter from the valves hitting the stock lifters which you can hear from idle till around 2300 rpm (slight ticking). Its not too bad though, an easily gets drowned out by my cat-back or the AC fan on level 2. The cams aren't going to damage the lifters based on their mild profile.


Thank you for such an informative response! I don't plan on doing any of the engine modification myself as I tend to be a second-try kinda guy, probably won't be doing any of this until around 2019 when more parts are available for our car *cough* turbo *cough* but Ive been please to see the results most people have had with the cams


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Thank you for such an informative response! I don't plan on doing any of the engine modification myself as I tend to be a second-try kinda guy, probably won't be doing any of this until around 2019 when more parts are available for our car *cough* turbo *cough* but Ive been please to see the results most people have had with the cams


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You're welcome, and good call. I made the mistake of installing this on my own, and its definitely not worth the trouble. Way too much time, stress, and problems along the way. Probably acceptable if it wasn't my daily driver.

I noticed that you were interested in the gains compared to stock. Forgot to mention that the 10-15 ft lbs gain I got was on top of the gains I already had with a 94 octane tune and stock cams. So I would say I gained around 25-30 ft lbs compared to stock with my 2nd gen 2.0 setup. I've also been in touch with another member that got ~35 ft lb gains compared to stock on a recent dynojet with his 3rd gen Mazda3 2.0 running stage 1 intake and exhaust OVT cams and tune #3 from OVT (unfinished). He's now also looking at turbo options, and the cams will enhance power gains with boost on these engines which suffer from small cylinder head intake/exhaust ports ;)
 

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I'd like to locate a 2016/2027 CX9 totaled from the driver's door on back and get the engine trans and ecu for a much improved CX5 or quicker 2016 Mazda 3.
 

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Damn I ordered the stage 2 not knowing I'd need upgraded springs. Anyone know what springs I should get to pair with the exhaust cam?


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Damn I ordered the stage 2 not knowing I'd need upgraded springs. Anyone know what springs I should get to pair with the exhaust cam?


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If you got the cam from OVTunes they have the springs you need.
 

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