36 replies to this topic

[Arno]

Their solution looks like that:

https://a.d-cd.net/9837299s-960.jpg

https://a.d-cd.net/6437299s-960.jpg
 
Don't know what is todays price, but you can contact them directly via the web page or/and what's up number there.

 
 

Looks like a very neat install. Only thing I'd be worried about is cooking the Davies Craig waterpump (mostly the plastic housing) with the exhaust manifold also quite close in that area.
 
Would probably need some very good heat shielding/insulation around it to keep the  waterpump alive for a decent time.

 

I guess the alu version of the Davies Craig is bigger, so might not fit in such a way.

 

Bye, Arno.

[Vladimir]

I'll test this solution, hopefully soon/this summer. Getting the engine assembled at the moment.

[blackoctagon]

That is a fantastic adapter plate. It really makes the EWP solution much more useful.
I suspect it's not cheap, but the integration is fantastic.
I was going to use a BMW/Pierburg on the next engine after my current build, but this would make me look at the Craig Davies again.


Vladimir,
what secondary chain tensioner are you referring to?
The camchain tesioner is in the head, and not part of block, and it's oil pathways.
The balancer tensioner is just spring tensioned (i'm confident on this as I have one on my desk here) and does not get oil fed.
Is there another part that is oil fed?

[blackoctagon]

Vladimir,
I owe you an apology - I went out to the block, took the tensioner with me and, as you said, there is an oil gallery from the bottom of the balancer shaft bearing housing that matches up with the indented section on the bottom of the tensioner.

Looking at the design of bearing carier and spring tensioner I do not think it's there to provide full hydraulic oil pressure on the tensioner - instead I believe it provides oil to act as lubrication and a damping force on the spring.
Regardless of full or partial pressure it is still an oil feed.


The GM Performance and the aftermarket kits blank the bearings fully, so this makes me think that the damping is not needed.
The pulsating forces on the balancer chain are mostly from the shafts and will be large and low frequency.
The crank and the pump do still provide oscillation but lower in magnitude and higher in frequency.
So I suspect that GM Performance made a decision not to bother with feeding the tensioner and letting the spring do the work, hence just blanking it all off.

Edited by blackoctagon, 22 February 2021 - 06:56 PM.

[Arno]

I was going to use a BMW/Pierburg on the next engine after my current build, but this would make me look at the Craig Davies again.
 

 

Biggest advantage of the Pierbug pumps is that they are designed in an OEM setup to be used as a 100% full time waterpump and should run for many, many years.

 

Davies Craig pumps come in from the race/drag world where anything that survives a number ouf outings without fialing is fine and are often used as auxilliary or helper pumps where a failure is not such a big issue.

 

It's mostly the electric motor that's the issue here. The pierburg ones are massive compared to the davies craig offering and in electric motors 'big is better' in many cases for longevity.

 

For a dedicated waterpump in a road car I'd go with a pierburg or similar OEM offering any time. For a more track/race setup, the davies craig will be fine and a chunk lighter to boot..

 

Bye, Arno.

[blackoctagon]

I like the Pierburg solution, although I want to weigh one first and look at the power consumption - it may not be as useful as it first seems as these things are done primarliy for warm up emissions and not for crank power, and I run a smaller alternator that may not appreciate the current.
I see you can get unbranded ones from the people who probably make them on ebay, so i'll probably pick one up anyway.
That is for the next engine though.



I got the 2nd prototype chain guide in and tested:








Thats the final guide design and it has been sent to the manufacturers and the delivery clock has started.


These photos are of the oil feed in the left hand balancer shaft bearing housing and the transfer hole to the water pump chain tensioner.
Entry of feed:


Exit of feed to tensioner


This is the bushing i've come up with to ensure the oil goes to the tensioner.
I'm not convinced GM Racing or the US aftermarket and enthusiasts bother, and by all accounts it's not a problem for the tensioner, but I can do it so I will.


And it pops in here.


As simplified cross drilled solid bushing would also work, but I like drilling the centres out of things for weight.

Edited by blackoctagon, 23 February 2021 - 10:15 PM.

[2-20]

Very nice engineering ...
This bushing doesn't interfere with the new chain guide ?...

[blackoctagon]

The large diameter on the bush is only 2mm thick.
The production guides had a rebated section added (removed?) underneath so that anyone who uses that/similar bush solution will have clearance.
I designed it so the guide will hold the bush in place, if for some reason it ever came loose.

Although if a press-fit bush becomes loose in a 24mm thick aluminium block wall then you probably have other, more serious, problems with the engine.


I should maybe point out the bush in the photograph was not pushed all the way into the block - it was only placed for the photo.

Edited by blackoctagon, 24 February 2021 - 09:41 PM.

[2-20]

Ok thanks...
As i said very nice engineering...

[blackoctagon]

The second protoype bush was finished:





It wont need a third protoype as this is the right design. A cross drilled bush would probably be more awkward as the oile delivery holes are not at 90 degrees, and also once the bush is in it would need drilled and gouged out or the crank to come out if there was ever cause, whereas a big centre hole lets a puller in.

I'll now make up a new bush - P2 was a working fit and not an interference fit - and shrink it in once the chain guides arrive.

[FLD]

Are those holes radially aligned?  I'm just wondering if your oil groove could go right round making the bush an easier fabrication.  Kinda academic now I know but could help someone else out.

[blackoctagon]

The holes are slightly different sizes but they share a common edge, so you could use a full radial groove that picks them both up.
My objection to a full groove is only that it becomes an unnecessary oil resevoir, but theres an argument that says oil is lighter than aluminium so a full groove part is lighter.

If I were making these for others i'd probably do a full groove and advise and extra two teaspoons of oil.

[FLD]

advise and extra two teaspoons of oil.

 

PMSL

[blackoctagon]

I collected the first batch of chain guides this morning.


These are in the proper plastic, and they are all in tolerance against my drawings.








TheHood, 2-20 and ayresyy have asked for them - you have messages - and I increased the batch size so there are 5 more available if anyone else is looking for one.


On a side note I was asked by some Cobalt people and a Saab person about the blanking plugs, so i'll be getting some thick wall (tensioner oil groove) and thin wall (right hand hole) plugs for them.

[blackoctagon]

People on the waiting list for chain guides and oil blanking plugs - please see your messages.


The other chain guides are now all gone, but I have another big batch coming in three weeks.
I had forgotten that things like Astra VXRs and some Vectras had z22se and other L850 family engines and those folk would want the short chain.
I can only presume people prowl the vx220 forum who drive other cars, because i'm not exactly advertising.

[blackoctagon]

I finally got production sorted on the blanking plugs, to the correct tolerance.

This set is about to be posted (click for bigger):


The chain guides have been re-designed with a rebate to allow the LHS plug to be fitted and then the guide sits over the plugs's lip, acting as a shoulder to ensure the plug cannot wander.

However, from my own block and the goodness of fit not much short of catastrophic block failure and the rupture of the 23mm thick block wall around the plugs will move them, at which point you have other and more pressing issues.

[blackoctagon]

I finally got around to collecting up all the bits and pieces for the short chain to do a comparison:

On the left the new bits, and on the right the old bits (assuming you've already had a balancer shaft-ectomy):


A chubby 795g for the cut-down solution:


A slender 338g for the


A pleasant 457g weight reduction.


Full balancers shafts themselves weigh 1356g, each.


The stubs weigh 263g, each.


So the full balancer shaft delete and short chain conversion saves 2.643kg.
The real benefit is in the inertia reduction and it's impact on engine response, but less mass is always welcome.