Mark
I was just re-reading you interesting information on the flow capacity of the V12 inlet arrangement and I wondered about a couple of things.
What did you use for the surface roughness of your ducts?? Did you adjust the roughness and see how much difference it made??
Did you, by any chance, model the “standard” inlet filter can to see what effect it had on the inlet flow potential?
Regards
Matt
Hi Matt,
I had a default roughness set (need to look up what it was), but I can chage it to see the impact.
I have modelled the standard inlet filter case. However I don’t have exact dimensions for the “trumpet” that feeds the inlet filter. The parts I modelled came of a car where the previous owner had cut the inlets off and welded a cone filter on. From what I can see from online photos, there is a slight taper and a 90° radius on the inlet???
(My work is stalled because my Volvo SW (it’s the dogs car) failed its MOT. Testing station thinks its the power steering. Bollocks. But it is leaking more oil than a sad XK. Thought it was the new PCV system I installed, but turns out its the cam cover AGAIN. In between fixing my daughters 306 (torsion bar rear suspension sagging) and now the Volvo, my Jag projects are gathering dust. However I am now the proud owner of a fuel injector test system and hope to be able to video the injectors doing their thing to look at their atomisation and spray patterns.)
Hi Mark
Yes…other stuff always arises when you are time scarce…cam cover “again” ?? Have you not converted to Loctite 518 yet!!!
I bought some spare air filter cans and cut them open leaving just a skeleton to retain some stiffness in the cover which allows it to clamp the filters in position. I left the air temp sensor in the trumpet section and cut it off after the sensor to retain a slight breeze past it. Now I’ll get reasonably even face velocity over the filter and a fantastic sound on what I like to call “full noise” !!!
I’d be curious to see what the actual flow difference is modifying the inlet filter cans. I measured the inlet trumpet on my unmolested can.
The inlet tube is a cone starting at 38mm I/D and ending in 46.5mm I/D .But…it is cut down the middle and the 46.5mm end has 13mm added so the diameter centres are separated by 13mm. The 13mm is added in the vertical direction as the can sits on the car. On the end is a radiussed piece that ends at 57.5mmO/D with a radius of about 10mm. The centreline length from end of entry trumpet to penetration to can is 245mm. The tube is at an angle to the clamping face of 25 degrees …so on the car it tilts toward the engine so the 25 degrees is in this direction to the mounting face. One of the 13mm flat faces enters the can at about 15mm from the clamping face and on the centreline in the other direction. The tube spigots into the can by about 10mm. The wall thickness is a bit over 0.6mm.
Be interesting to see how well this works…
Regards
Matt
I really like the Volvo 5 cylinder, but the cam cover (which covers the entire head) has pressurised oil running between the flange faces, and the seal needs to be perfect. I originally used 518, but the head had cooked and it was both warped and a bunch of bolts weren’t holding tension. When I flattened the head I found the 518 difficult to remove (something I had not experienced before). So when I put it back together I used the recommended Volvo sealant, which is a blue goop with a 300°C rating. It looks a lot like Hylomar. However, I didn’t deal with the cover bolts (of which there are 24) more of which were now not holding tension. I hoped it’d hold well enough. It didn’t. Thus the blue goop oozed out in places. So I helicoiled the offending bolts and resealed it. Now I find there are a further 5 bolts not holding tension and I’ve got lots of oil leaking again. Sigh. It looks like the blue goop works so long as the flanges are tight. But I might go back to 518. That stuff seals. And I DO NOT want to do this again. Unfortunately I’m not sure which bolts I’ve helicoiled and which ones I haven’t. This time I need to make sure ALL of them are tight.
Egads…the cam cover has pressurised oil running between the flange faces…so a machined groove or some such that carries pressurised oil in the flange face??? What sort of magic is this???
Matt
Now I find there are a further 5 bolts not
holding tension…
I dunno the situation, but in such cases I suggest installing short studs with
JB Weld or some Loctite product that’ll never let go, and then use nuts for
retention instead.
– Kirbert
My reading of the situation is that it is a lovely solution for a fresh engine from the factory. But with 275,000km on the clock, the poor old girl is getting blxxdy cantankerous. It’d have been better with studs, but I guess they never figured it’d come apart so often. I’ll heli-coil the remaining threads and replace the cam seals (again). But I am debating with myself whether to use this blue goop or go back to 518. The blue goop has come off very nicely, but I’m now beginning to think that it is a generic gasket sealant, not necessarily specifically designed for this application. 518 is rated to 0.015" gap, I think. There were signs last night when I pulled it apart that some faces were weeping. Given the head had warped, I should have flattened the cam side as well. sigh. In fact, it would have been smarter to buy a new head which appear to be available for $600 complete with cams, valves and cam cover! (Sorry - I’m off topic! My wife tells me I should just scrap it - but I am getting more and more stubborn and the dogs are glad to travel in the style of Swiss royalty.)
Get a breakdown in the seal at any point and you have oil leaking into bolt holes, into spark plug cavities, or out the sides onto exhaust or down the front/back of the block. Sigh.
But I am debating with myself whether to use this blue goop
or go back to 518.
Hylomar is a gasket dressing, not a sealant. It never hardens, remains
gooey forever, so eventually it just oozes out of place causing a leak. If this
blue goop is similar, it should not be used in PLACE of a gasket, only
APPLIED to a gasket.
Suggestion: If this application uses sealant only, no gasket, use the 518 –
but use the narrowest bead you can manage to apply. A very thin
continuous bead, making little rings around each bolt hole.
– Kirbert
Mark
Noooooo…if you’re going to feed pressurised oil in that fashion then you keep the milling cutter busy and surround the oil supply with a nice “o ring” style oil seal so that it doesn’t leak. The Nissan SR20 engine has a nice cam cover seal. O-ring and shoulder bolts so the pinch on the o ring is controlled and guaranteed.
Still…I like Kirby’s idea of loctited studs…that’ll possibly supply a bit more clamping force at the prescribed tightening torque.
Or…here’s a novel idea…you could listen to your wife!!! ( heh heh heh)