How Ti-VCT works

[Roadsport]

I found this highly interresting.

[trig]

intresting but bit of a head scratcher I feel its just something to go wrong or its gona cost...

I got a ST170 motor with VVT on the inlet only cant make my mind up if to keep it or not???

[TTommy]

wonder how it is effected by wilder cam profiles in regards to oil pressure.

[Roadsport]

For a highly tuned engine running mostly high revs I believe its not much of a use.
But I do believe its yet another high end trick of the future to achieve even flatter power curves. With small engines there's something to gain in the otherwise limited low and mid range power.
It just might work well in racing engines as you change the oils more often than in the road going cars. I am very intrigued by this all. I could use such a head with my bottom end and my ECU seems to support "vanos".
I've seen more than a few Ti-VCT engine with issues caused by the gloging VVT solenoids. Which is a quick fix really but if the cam pulley / VVT unit goes thats more expensive.

Haven't heard of any VVT issues with the Pumas or ST170's but they really scarce around here so cant compare to Focus Ti-VCT


The problem could be to find cams able to take the VVT modules. You would be pretty much limited to a re grinds and maybe a high cost custom job.

[Roadsport]

wonder how it is effected by wilder cam profiles in regards to oil pressure.

I believe dry sump pump would sort that out. Which is essential with Sigma / Zetec SE based racing angines.

[TTommy]

surely a step in the right direction though.

i cant see it being of much use in a race engine were you are going to be 6k plus most of the time.
more weight and complexity imo. trouble with wear iand tear if your going to be using wild cam profiles with heavy springs.

maybe help with turbo lag in some engines that have had the compression dropped through the floor but thats not OEM anyway is it?

i do love abit of complexity it is wonderful how some things work.

[Roadsport]

Propably so. They really are heavy compared to alloy vernier pulleys. But one can't really know until someone gives it a go.
Does the BTCC engines run VVT? S1600's?

[exboyracer]

I know that when Honda ran the Accords in the BTCC they had to diable the VTEC system as part of the regs. As has been said already though, the conditions a race engine are used in would mean that the VCT system would be effectively locked into one mode anyway.

For roads cars though I think it's a great idea, you can have a high performance engine with good low speed torque.

[Roadsport]

What about them narrow hairpin type curves? I bet with a Ti-VCT you would get some advantage over conventional engine accelerating out of a slow corners where mid range plays a big role.
We have a lot of corners on on finnish track where the revs drop to 5000rpm's. Get a gain there and you will be gainig the whole following straight.
But if the VCT would only aid the 2000-3500 or 4000 rpms I'd not bother. On a race car.

[M11rf]

Very interesting indeed just to know how it all works... and interesting to know a woman knows more about it than me

[exboyracer]

I was wondering how bored she must have been reading all of that out

[Philipjb]

This is the video I was talking about that was so informative. I've tried to watch it now, but it is marked "Private."
Thanks again for your help!
Phil

[Roadsport]

That video is only a link to youtube. The person who listed it on youtube must have listed it as private. I only posted a link to the video. I did not upload it to youtube.

[Philipjb]

OK, I understand now. Thanks just the same! I'll have to look elsewhere for comparable videos on the subject. This technology is interesting! Our company continues to increase production to our customers in various car markets.

[smokeybeansie]

The VCT system is mainly used on modern raod cars for emissions reason rather then performance.
It replaces the EGR vlave. The new 1.6 ecoboost engines run VCT on both inlet and outlet and i've seen it in combination with motorsport ecu's but that's with turbo engines.

[mk2mania]

intresting but bit of a head scratcher I feel its just something to go wrong or its gona cost...

I got a ST170 motor with VVT on the inlet only cant make my mind up if to keep it or not???

iam nearly there with my motor and the mapping is only 2/3 done , but it dont half pull well low down,, thats running the vvt with 45 jenveys and s60 ,, the mapping wizard spent loads of time doing the lowdown stuff,, then my box let go (tail shaft split) bad propshaft,, so next time ( soon) on the dyno should have good results,, i still need to 100% dial the cams in aswell