EVOkeeper

iTrader: (1)

I know the GReddy adjustable cam gear for the Intake (mivec side) has been discontinued for a long time now, let alone it was a hard find back then.

I would like to see what arguments you folks would have about this particular item.

the complete one is for the exhaust side, and the 2 pieces in the picture is for the mivec/intake side.

I know how mivec works but this mivec cam will change the lobe separation angle when mivec is engaged, and I assume when it is altered mechanically in conjunction with mivec, it may increase this advanced measurement more aggressively, now my idea is to tighten it a little so when it "advances" it doesnt advance so drastic as to make valve to piston contact.

Im thinking of tightening the LSA (lobe separation angle) and benefit from that since mivec will widen it and I will benefit from that too, maybe I can have both benefits on a single powerband?

I need some points of view and advice from tuners or people with experience is preferred.

And if you need more factors as what would be the results with mods, this will be paired with HKS 272's and ferrea valve springs and retainers.

211Ratsbud

iTrader: (1)

Interesting product, and I at this point think you should look into the reasons which people modify their oem cam gear. Typical of non stock block builds to get back mivec adjustment. I started a relavent thread a while back on mivec for stock blocks seeing where we could gain anything.

Do you have more info on it's capability or function?

EVOkeeper

iTrader: (1)

The main reason why people modify their stock intake cam is because no one make adjustable ones anymore, but just lke anything, that hasn't stop people in the history of tuning from being creative.

This thing came in with japanse documentation, on what looks like instructions to install but it seems to have more info on it but I cant understand. probably it gives a brief explanation on how the system works and what are the benefits from it, but this is just an assumption.

last piece of information is that the blue ring has markings and they account for 20 degrees +/- adjustability.

So If im not mistaken, Mivec engagement makes up to 28* advance. now when I mechanically adjust the lobe separation angle, this will directly increase the mivec advancement. my concern is that it may throw the valves so forward in advance that 1-it doesn't even seal the chamber to combust properly, and 2- it will have the intake valves so aggressively open while the piston is coming up making contact and messing things up. as of right now, I am doing much research in all this before install.

As a final test, I will adjust this cam gear and manually engage the hydraulic function of mivec and then turn the crank all together and see if it makes contact, this way I can see if extreme cam adjustments may or may not contribute to piston to valve contact.
If it doesn't contact I'll be more comfortable making adjustments w/o fear of mayor damage.

211Ratsbud

iTrader: (1)

You are mistaken. 28.8 Positive and 1.2 negative from zero.

Point taken, however I believe it is a feed back loop so you may enter 28.8 and it will be 28.8 no matter where it started from.

Several others have already worked out the max advance with mivec before interference. Probably easy to find: here's what I originally started exploring "
https://www.evolutionm.net/forums/showthread.php?t=673868&styleid=28 "