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[AndyStobbs]

Hi all, just posted in the introductions section, basically I need some help on accurate valve timing for the Y32SE engine.
I'm building this engine for a conversion and pretty much going all out on it (within reason), I'm running G camshafts on inlet and exhaust and want to tweak the timing so as to get as much torque as possible low down and in the mid range.
I'm wondering whether anybody has established a good setup for the timing. I can easily set it to the marks on the backplate, but that's not necessarily the BEST set up.

Any help appreciated guys.
Thanks

[Entwood]

The V6 NEEDS/REQUIRES/INSISTS on the CORRECT timing tool .. using the backplate marks is guaranteed just one thing .. the timing WILL be out.. no ifs or buts .. correct tool or don't bother. ..

Stick up your location, if you are lucky there might be someone near you with one ...

[AndyStobbs]

I'm on the Wirral. What are you referring to by 'the timing tool' just a pulley locker?
I beg to differ somewhat on the back plate marks being hopeless. I was getting 211bhp from my Y26 on the backplate marks. Admittedly with other mods but clearly the cam timing wasn't a mile out.
I want to DTI this engine, but need to know some reference points for valve opening BTDC etc.

Will I have to keep answering the 3 questions everytime I post?

[bigegg]

I'm on the Wirral. What are you referring to by 'the timing tool' just a pulley locker?
I beg to differ somewhat on the back plate marks being hopeless. I was getting 211bhp from my Y26 on the backplate marks. Admittedly with other mods but clearly the cam timing wasn't a mile out.
I want to DTI this engine, but need to know some reference points for valve opening BTDC etc.

Will I have to keep answering the 3 questions everytime I post?

probably 

your question is about adjusting the timing away from the standard timing, to match a non-standard set up, rather than just resetting the timing after changing the cambelt - which is the question that usually gets asked and for which you *need* the "timing tool"

chances are 2woody or someone will be along soon to give you a complete answer with sums and other complicated stuff.
 

[andyc]

You could replace the normal cam sprockets with Vernier ones. Set them to Zero on the scale and set then timing as normal. Once you have the timing set you can then adjust the cams with a dial gauge without the belt moving.

Cheers
Andy

[AndyStobbs]

It's knowing where is a good place to set them though. I will get verniers if I need them, but its all meaningless without tested values for valve timing. I don't mind r and d but at £40/run on a dyno its expensive R and D.

Thanks

[dbug]

As a start point set them up correctly as standard - no good using the back plate timing markings, you need to use the proper timing kit incl gauges for accurate timing as others have said

[TheBoy]

Can't help with the info you want on custom timing, but agree that to get a baseline to work from, starting out as standard is the starting point.

The timing kit comprises of crank lock, cam locks, but also a timing template that sits over each pair of cam sprockets, as the markings on the backplate aren't even a guide.

The GM V6 uses an infinately variable setup for cam timing, hence needing the cranklock and the timing tool to get it on "properly" (note, properly might not be where you ultimately want to end up with your project).

Hope that clarifies, even if it doesn't answer your original question.

[AndyStobbs]

Yes I see where you are coming from. Basically so far I have found the centre of TDC which amazingly was bang on where the pulley slot is.
I had marked the position of the eccentrics prior to removal as the engine had a timing belt kit fitted at a Vauxhall dealership 3k miles ago. Would guess they use the tools for locking up - but maybe not.
I found on those original marks that bank 2 was ahead of bank 1. Essentially where I'm at now the marks are off from the back plate but both banks are phase in terms of position relative to TDC. Like you say its a good starting point, but that's all it is. Might just have to bight the bullet and hit the rollers a few times once I finish the build.

Aiming for a solid 250bhp on this engine, in a vectra with 'hybrid' plenums - all matched up, tubular manifolds, remap, g cams, and a little matching up of the inlet divider. Fingers crossed...

[TheBoy]

Good luck with the project, let us all know how you get on

[2woody]

there is, unfortunately, no precedent for such.

Granted, the "G" cams on both will yield an improvement, but no-ones appears to have done it, yet alone published a dyno plot to prove that it works.

I think from memory that "G" differs only in lift, so its reasonable to assume that standard timing will suffice. Just make sure you have enough valve-to-piston clearance.

Doesn't the Vectra have a unique plenum ? the Omega one might be of some advantage to you.

[AndyStobbs]

I had done quite a lot of development on my y26. It started as a standard cdx spec which dyno'd at 179hp. That was on A inlets and E exhausts.

Then I did a lot of things at once to it, including G inlets and A exhausts,  3.0l inlet divider. Knocked out all of the cats but retained the now empty manifolds (slightly different set up on the vectra), matched up the plenums, smoothed out a big step in the TB and polished it. Then it got dyno'd again and made 198hp with the airbox but 211 with a px cone.
Was clearly running very rich at this point which was hampering it, but at the time nobody could remap a motronic 3.1.1 locally. Tried a 3.0 bar FPR which leaned it out but must've ruined the spray pattern as it was more lumpy when cold, and was still too rich anyway.

Went back to the 3.8bar FPR (standard item) and eventually added G exhausts, got it dyno'd again with the PX cone (with an added heat shield this time) and found it had dropped markedly to 198hp. Really struggling now with the excess fuel, its like being on choke.

Feeling really dissapointed I decided to get some smaller injectors, as remapping was still not viable. Sourced some Nissan micra injectors that I had calculated would reduce fuel to where I wanted it, but never got around to fitting them as I got the opportunity to sell my engine to a customer and so now I've got the y32.
I've pretty much been the development route so far as the above goes but never played with cam timing.

Yes the vectra has a different plenum set up to the omega, and I've got a long snout setup on the y32 engine which I may end up using in the vectra. But the vectra plenums are a thing of beauty, but a compromise on space. The TB is tiny in area terms compared to the twin omega unit.
The development continues, been building the engine today, now at the point where I need to make the tubular exhaust manifolds.

[philhoward]

Odd that you mention it running rich - a problem I have (as do others by the look of it).  Only seems to be a problem when the system goes open loop - like on a full bore dyno run.  I'm not that happy with it sitting richer than 12:1!

[AndyStobbs]

Yes the mapping for WOT is atrocious, as you say. On idle and all steady state conditions the CL fueling is kept in check at or very near stoich. A rich OL map is erring on the side of caution but the degree to which Vauxhall have gone is ridiculous. Mine was always off the scale at 10:1 AFR, got the dyno graphs to show it, you can just see the torque curve slowing down as the AFR drops.
With the 3.0bar FPR I was getting a worst case of roughly 11:1 AFR, better but not in the region I want to see it, and as said above it wasn't the same animal.
A firm local to me can now remap the ECU so this one will be getting a remap.

If anyone is interested in continuing my development on a 2.6 I still have the 8 micra injectors and plugs to suit (different connector, but same impedance and pressure rating). I was amazed to find the exact same injectors in the 3.2 as in the 2.6. No wonder there are over-fuelling issues.

[Kevin Wood]

The first thing I'd say is don't mess about playing with the fuel pressure and injectors to try and influence the mixture. Get a wideband lambda sensor and a proper aftermarket mappable ECU such as a Megasquirt or Emerald, etc. and map it properly. The stock ECU is mapped for a standard engine only and once you've strayed far enough from a standard engine it will never run acceptably.

That said, I can't see how it's running rich on the standard map yet making more power. Something doesn't add up. Do the before and after power figures come from the same dyno under the same conditions?

An engine will always run rich on full throttle to avoid destruction, and 12:1 strikes me as being about right. You may get a little more power from a multivalve engine by going to 12.5-13 or so, but I'd expect the manufacturer's mapping to have erred on the side of safety, so 12:1 doesn't surprise me.

10:1 is a bit smoky, though!