Do “reputable” tuners use lean spool disable
Jun 4, 2008, 12:00 AM
#31
Amak,
the MIVEC is advance up to 28.8* and -1.2* for a total variable motion of 30*.
At this point with stock cams and S1, S2, Crowers (spit), HKS, JUN, stock, stock intake with 272/280 etc. Exh, Cossie 272, M2, and M3 there is very little that has been tried and experimented with. Bryan and I have been bouncing ideas off each other since Ecuflash tuning for the IX began so please recognise that research is and has been conducted.
This is really sposed to be about lean spool so lets talk about the MIVEC affect or lack thereof in a new thread please.
Also for your information, unless you are a vendor or operating out of a vendors shop, you arent sposed to advertise services they frown on such things here
.
the MIVEC is advance up to 28.8* and -1.2* for a total variable motion of 30*.
At this point with stock cams and S1, S2, Crowers (spit), HKS, JUN, stock, stock intake with 272/280 etc. Exh, Cossie 272, M2, and M3 there is very little that has been tried and experimented with. Bryan and I have been bouncing ideas off each other since Ecuflash tuning for the IX began so please recognise that research is and has been conducted.
This is really sposed to be about lean spool so lets talk about the MIVEC affect or lack thereof in a new thread please.
Also for your information, unless you are a vendor or operating out of a vendors shop, you arent sposed to advertise services they frown on such things here
.
Last edited by JohnBradley; Jun 4, 2008 at 12:12 AM.
Jun 4, 2008, 09:28 AM
#32
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Evo IX w/ what mods? can you list them out? jw...
I respect your's and Jb's research and tech info on Mivec, but I am testing my Evo IX w/ cossies. I hope to put out a solid Mivec map for cossies that will hold more top end power, and have a better spool up, but also smoother for daily driving..
Jun 4, 2008, 11:04 AM
#33
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mivec sole purpose is to change the intake valve, it just does it through the use of the CAM. Sorry for not stating the "obvious".
all the intake air is already "metered" by the ecu, so increasing MIVEC is not magically increaseing the air to fuel ratio. You have a set air quantity and you just control when that air enters the chamber. If any of that metered air is sent right out the exhuast valve before the combustion takes place your air ratio will decrese. Thats why to much MIVEC is not good in high RPM and is why you see factory numbers really small or zero'd out completely.
your statement of decreasing mivec to increase spool and smoother throttle is incorect.
your right, i think,about mivec causing knock issues though, I actually experienced this during MIVEC extreme testing. say your car is already pig rich and after the cumbustion takes place there is lots of extra fuel not burned, this along with heat and aggressive mivec letting air into this heat and fuel chamber can cause another combustion flame to be developed causing knock.
makes sense to me.
read up on it. But Mivec retards the intake cam, thus letting more air/fuel into the combustion chamber before the explosion, producing a larger combustion=more/faster turbo spool=more boost=more power. This isnt just a guess. I have proven it, and shown others how to hold more boost, using this method. I have shown 3 other people, and each person has seen more boost and more power, in 2 different cars.
I havent done thouroug testing on Mivec down low, but I will be doing that shortly. My hypothesis, is that less mivec timing down low, will help out with a smoother throttle response, better mpg, and perhaps a faster spool up. Thats just my guess, I will start tuning low-end Mivec later next week.
Mivec can greatly affect AFR, and can cause the car to knock less/more. I have done extensive testing w/ different Mivec maps, but using the same timing and fuel maps. All I did between pulls was change the Mivec Map.
I hit higher boost with more Mivec timing. end of story
I havent done thouroug testing on Mivec down low, but I will be doing that shortly. My hypothesis, is that less mivec timing down low, will help out with a smoother throttle response, better mpg, and perhaps a faster spool up. Thats just my guess, I will start tuning low-end Mivec later next week.
Mivec can greatly affect AFR, and can cause the car to knock less/more. I have done extensive testing w/ different Mivec maps, but using the same timing and fuel maps. All I did between pulls was change the Mivec Map.
I hit higher boost with more Mivec timing. end of story
Jun 4, 2008, 01:12 PM
#34
If it was doing what you are saying then the results would be totally backwards. The fact is, more advancement (higher numbers) in the mivec table promotes quicker spool and more peak torque from higher cylinder pressure. If it was the cam retarding, like you are saying, the results would be the opposite.
This is the whole advantage of the Mivec system over the non-Mivec. The best of both worlds. Advanced intake cam down low for response, spool, and torque, and less advancement up top to promote more power, and everything in-between to customize for different setups.
Asking for the mods just means you missed the point.
Last edited by razorlab; Jun 4, 2008 at 01:46 PM.
Jun 4, 2008, 01:37 PM
#35
I turn it off for all Evo 9's as some of them I just can't get "rich" enough for 91 octane at peak boost through the midrange. It also makes a huge difference in fuel tuning for all the other gears, espically when you row through them instead of just single pulls. Makes the AFR much much much more consistant on the street.
The 03-05's I don't see the same issues of too lean at peak boost through the midrange but I turn it off for them as well for the per gear fuel tuning.
The 03-05's I don't see the same issues of too lean at peak boost through the midrange but I turn it off for them as well for the per gear fuel tuning.
Jun 4, 2008, 02:17 PM
#37
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mivec sole purpose is to change the intake valve, it just does it through the use of the CAM. Sorry for not stating the "obvious". all the intake air is already "metered" by the ecu, so increasing MIVEC is not magically increaseing the air to fuel ratio. You have a set air quantity and you just control when that air enters the chamber. If any of that metered air is sent right out the exhuast valve before the combustion takes place your air ratio will decrese. Thats why to much MIVEC is not good in high RPM and is why you see factory numbers really small or zero'd out completely.
your statement of decreasing mivec to increase spool and smoother throttle is incorect.
your right, i think,about mivec causing knock issues though, I actually experienced this during MIVEC extreme testing. say your car is already pig rich and after the cumbustion takes place there is lots of extra fuel not burned, this along with heat and aggressive mivec letting air into this heat and fuel chamber can cause another combustion flame to be developed causing knock.
makes sense to me.
well, I will do some dyno runs to prove to you, that more Mivec timing up top, for a Cosworth cammed evo, will produce more boost, which in turn, will allow for more power to be tuned. I should be getting on a MD tomorrow.
Jun 4, 2008, 02:23 PM
#38
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You are incorrect. Higher numbers mean more advancement of the intake cam.
If it was doing what you are saying then the results would be totally backwards. The fact is, more advancement (higher numbers) in the mivec table promotes quicker spool and more peak torque from higher cylinder pressure. If it was the cam retarding, like you are saying, the results would be the opposite.
This is the whole advantage of the Mivec system over the non-Mivec. The best of both worlds. Advanced intake cam down low for response, spool, and torque, and less advancement up top to promote more power, and everything in-between to customize for different setups.
Asking for the mods just means you missed the point.
If it was doing what you are saying then the results would be totally backwards. The fact is, more advancement (higher numbers) in the mivec table promotes quicker spool and more peak torque from higher cylinder pressure. If it was the cam retarding, like you are saying, the results would be the opposite.
This is the whole advantage of the Mivec system over the non-Mivec. The best of both worlds. Advanced intake cam down low for response, spool, and torque, and less advancement up top to promote more power, and everything in-between to customize for different setups.
Asking for the mods just means you missed the point.
I understand what you are saying. But I have seen more power, w/ more mivec timing up top. I will do some dyno runs, hopefully tomorrow. I get more boost w/ more Mivec Timing, and less knock, ofcourse after tuning around the Mivec. And I feel like my car is much more stable w/ more timing up top..
Jun 4, 2008, 02:39 PM
#39
This whole time you where saying that higher mivec numbers in the mivec table where retarding the cam. I saw this, and that statement is 100% incorrect.
Anyway, this has gone way off-topic. If you would like to continue this discussion about the Mivec system, please make a new thread.
Last edited by razorlab; Jun 4, 2008 at 02:50 PM.
Jun 4, 2008, 02:45 PM
#40
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So, the cam is being turned faster by Mivec? At the same direction of the cam gears? And is this a FACT? I know the drawing shows the angle of the movement, but is there any proof of which direction Mivec will actually turn the cam, during operation? Sorry if this question sounds dumb..
Jun 4, 2008, 02:56 PM
#41
So, the cam is being turned faster by Mivec? At the same direction of the cam gears? And is this a FACT? I know the drawing shows the angle of the movement, but is there any proof of which direction Mivec will actually turn the cam, during operation? Sorry if this question sounds dumb..
Last edited by razorlab; Jun 4, 2008 at 02:58 PM.
Jun 4, 2008, 06:40 PM
#43
When I go through gears I always get a richer mix at the higher gear when comparing the AFR of the same RPMs. For instance I see a 10.5 at 6K PRM on a pull but when changing gear I see a 10 at the same 6K RPM. Is this what you are referring too? Will Lean Spool Disable make the values the same?
Jun 4, 2008, 07:13 PM
#44
When I go through gears I always get a richer mix at the higher gear when comparing the AFR of the same RPMs. For instance I see a 10.5 at 6K PRM on a pull but when changing gear I see a 10 at the same 6K RPM. Is this what you are referring too? Will Lean Spool Disable make the values the same?
Jun 5, 2008, 12:23 AM
#45
WOW just wow. Bryan you have far more self control than I do or would.
Amak, if you want to make a business of tuning cars I really suggest you do what you have had recommended to you and RESEARCH. Your comment about knowing which direction the cam actually turns just baffles me. I am not going to be rude or make unneeded comments, but seriously if you think you can tune a car and do what you think you can, be ready to start shelling money on new shortblocks.
Amak, if you want to make a business of tuning cars I really suggest you do what you have had recommended to you and RESEARCH. Your comment about knowing which direction the cam actually turns just baffles me. I am not going to be rude or make unneeded comments, but seriously if you think you can tune a car and do what you think you can, be ready to start shelling money on new shortblocks.