Unique: New CAMS MIVEC and NON-MIVEC

Post by **smorison** » Wed Sep 08, 2004 9:18 am

we're probably only going to do these on an exchange basis... (definately for the TB and intake plenum)... the CAM's will probably be done the same way...

it costs about UKP80.00 to get the cams only to australia and probably a similar amount for hte intake plenum / TB / valley...

GWIDO, just to confirm there are two sets of lobes on each CAM.. a high speed and a low speed... this means there is twice as much machining to be done which takes twice as long which is why they will cost upto twice as much as the non-mivec cams....

a GR CAM set has 12 lobes and MIVEC cam set has 24 lobes...

spetz · Post by **spetz** » Wed Sep 15, 2004 4:12 pm

When will you be providing dyno readouts?
Is the engine going to maintain it's smoothness?

And is there any way of getting the cams ground from new?? ie not re-grind the old ones? I heard this isn't too good to do.

Post by **smorison** » Wed Sep 15, 2004 4:28 pm

the non-mivec cams became cost prohibitive... we weren't able to get reground ones made as there was not enough room to enlarge them...

we could still get them made but it would be cost prohibitive...

i'm waiting on the MIVEC ones to reach me from teh UK then they will go off for redesign....

spetz · Post by **spetz** » Fri Jan 21, 2005 11:24 am

So the MIVEC cams are just reground standard ones?

And how will valve springs/retainers cope with these cams?

And if you want to keep low cam lobe near standard, and "hardcore" high lift lobe, wont there be a huge loss in power between about 5700 rpm and when the "hardcore" high lift cam lobe starts making decent power? I assume it would need revs and plenty of them.

Any due dates?
Are you expecting a kick such as VTEC YO!!!!!?

Post by **smorison** » Sun Jan 23, 2005 10:26 am

spetz wrote:So the MIVEC cams are just reground standard ones?

And how will valve springs/retainers cope with these cams?

And if you want to keep low cam lobe near standard, and "hardcore" high lift lobe, wont there be a huge loss in power between about 5700 rpm and when the "hardcore" high lift cam lobe starts making decent power? I assume it would need revs and plenty of them.

Any due dates?
Are you expecting a kick such as VTEC YO!!!!!?

they'll be tested at the UAS track day... don't have an exact eta just yet...

i'd still like to keep the transfer from low to hi speed cams smooth and refined like the mivec and not that rough VTEC YO!!!!! kick...

the intitial ones will be reground ... however once the design is done we will be able to cnc new ones...

new springs and retainers will most likely be required... depends on the final changes and how agressive they are.

power loss - well its a bit hard to say at this time... there is already a power loss with the standard MIVEC cams so with anyluck it won't be any more substantial.

FTO338 · Post by **FTO338** » Fri Feb 11, 2005 9:58 am

Any news on this? Perhaps a dyno result of before & after would be great

spetz · Post by **spetz** » Sat Feb 12, 2005 11:28 am

Steve what I meant is that 5600rpm is the stage where the power curve overlaps between high and low cam therefore there is "no" power loss.

Where as if you have standard low can and a hardcore high cam, the high cam wont actually start making decent power untill higher in the revrage. Meaning after 5600rpm the low cam will be running out of power quickly, but kicking it into the high cam lobe will drop power drastically until it reaches the right revs?

What prices are you expecting the cnc ones to be, and when will they be available?

G_A_V · Post by **G_A_V** » Sat Feb 12, 2005 11:59 am

There is power loss in the stock cams when they change over, if you look at a dyno run of a mivec, when the cams change over it dips slightly.
They dont just overlap, and Im sure steve is looking at lower cams too

spetz · Post by **spetz** » Sun Feb 13, 2005 12:37 am

Gav,

I put no power loss in inverted comma's to imply that there is but it's not really noticable.
But if you change your high cam and not your low cam lobes, that power loss will be extremely noticable, and not only that but it will be a power loss over a few hundred rpm not just a dip as you mentioned

You can't change one cam lobe without the other.
You need to change lower and high cam specs, and MIVEC will engage at a later stage too (theoretically)

FTO338 · Post by **FTO338** » Mon Feb 14, 2005 10:23 am

Put on the DJ Hat "Hey pretty lady, let me c ya sexy body turn around &...... *BUMP* *BUMP* *BUMP*"

Whats happening

spetz · Post by **spetz** » Tue Feb 22, 2005 2:22 pm

We are left in the dark aren't we FTO338?

FTOluv · Post by **FTOluv** » Tue Feb 22, 2005 3:36 pm

i would have love to keep my FTO long enough just to get a hold on some hardcore CAMS for MIVEC. Would have showed my turbo budies a thing or two about NA cars

GPXXX · Post by **GPXXX** » Tue Feb 22, 2005 3:49 pm

FTOluv wrote:i would have love to keep my FTO long enough just to get a hold on some hardcore CAMS for MIVEC. Would have showed my turbo budies a thing or two about NA cars

...that you drive like a nanny on ecstacy?? rofl... JK buddy, JK!!

*runs & hides*

GPXXX · Post by **GPXXX** » Tue Feb 22, 2005 4:07 pm

seriously now - out of interest we tried deactivating the MIVEC whilst the car was still on the dyno by setting the activation point to 9000rpm (which effectively means it'll never engage).

What happened during the test was that the primary cams (non-MIVEC) ran out of puff at 6000rpm - we suspect the reason why the default MIVEC activation point was set to ~5500rpm was so that there is a continual buildup of power as the secondary cams kick in without sudden drop in HP (before the primary cams run out of puff...) to do this it needs to be engaged at a point just before the primary cams run out of puff and when the secondary cams starts to do its thing... within this 300-500rpm period, the computer automatically retards the timing to run rich (prob for safety / reliability reasons) so when it runs rich, it robs a little' bit pof power - which explains the slight dip in the power curve during the transition.

because we do not know what the specs of the duration and lift on this new cam, it's hard to guess on how it will affect the transition until it's fitted and tested on the dyno... one thing for sure though is that if you run a lumpier secondary cam (with higher lift and duration), you should expect significant mid-top end gains.

FTO338 · Post by **FTO338** » Tue Feb 22, 2005 4:42 pm

spetz wrote:We are left in the dark aren't we FTO338?

Well what can i say.....................

FTO338 · Post by **FTO338** » Sun Feb 27, 2005 3:13 pm

FTO338 wrote:Any news on this? Perhaps a dyno result of before & after would be great

16 days & counting

Post by **smorison** » Sun Feb 27, 2005 8:03 pm

update on this...

it's going on the back burner for a while... it's going to take me probably 4 sets of CAMS before we have a good solution... this really means lots of $$$ in R&D that i have to fund...

so it'll be towards the end of the year before i have a workable solution...