Page 1 of 1
FTO Mivec better?
Posted: Tue Sep 16, 2008 12:40 pm
by MarcoFTO
Whilst test driving a GT4 the other day, i was told by the dealer that the mivec's in FTO's were better than the newer ones made for EVO's and such, as the design and operation was changed. Does anyone know more about this and is lack of oil circulation a reason not to turbo the earlier (FTO) mivec's

Posted: Tue Sep 16, 2008 1:08 pm
by Bennoz
Most of the newer Mivec incarnations work only on the inlet cam lobe, where as the FTO system works on both the inlet & exhaust.
Yes, oil circulation can be a problem. The FTO's Mivec system is hydraulically actuated, oil is pumped from the sump & forced into the rocker assemblies which inturn pushes out pins that lock the high rmp rocker arms into place on the high cam. We've seen oil starvation cause big end bearings to spin when at high rpm for too long. Turbo would magnify the effects I'd imagine.
Posted: Tue Sep 16, 2008 1:12 pm
by Delvance
I'm not sure if the evo ix's mivec is just timing or timing and lift as well...i think it's only timing whereas the 6a12's mivec is timing plus lift on all cams. So that may be another potential difference. The lift these cams offer can cause crummy tuners to do a bad job on tuning a turbo mivec fto...but if the tuner is good, shouldn't present much of a problem though they'd have to be careful with the variables...and you also got the question of whether you need more upgrades to accommodate for the sudden increase in lift with air going in and out in larger volumes (e.g. can injectors handle it, does fuel pump need upgrade but only during big hp applications i'd daresay).
Posted: Tue Sep 16, 2008 1:14 pm
by Bennoz
Yeah, I think you're right, I think the lastest EVO's are actually inlet & exhaust.
Posted: Tue Sep 16, 2008 1:45 pm
by yano
Yeop. Mitsu's new 4b engines have both inlet and exhaust. Probably explains why the new lancers have 114kws standard too. Evo 9 was just a 4g63t with inlet. Other mivec engine we had was the one from an outlander that then got dumped in the previous gen lancers. Engine kinda sucked though, was only single cam, 2.4l and 115kw (detuned from 120kws overseas)
Posted: Wed Sep 17, 2008 2:38 pm
by MarcoFTO
So, much to consider if turboing 95' Mivec.
Thank's guys, much appreciated!

Posted: Wed Sep 17, 2008 3:51 pm
by I8A4RE
Unless you know someone who is an absolute tuning guru.......dont do it. Gr conversion then go for gold