Hold(en) my beer - Monaro, Ute and Commodore content

[SturdyHSV]

It survived, the oil pressure isn't rising with revs as it should, so maybe oil pickup o-ring (very common to cock up) or something of that ilk, I have some sump off work to do anyway!

Dyno the gear ratio wasn't quite right (torque / hp don't cross at 5252 like they should) and we had no timing in it, so the power figure is fairly irrelevant, but also comically low at around 420 at the wheels, it was estimating 500 fly and 520lb ft, they weren't too sure how to get wheel horsepower so take it with all the salt for now!

Driving it back, it feels much like it did just with the cam in terms of shove, although hard to remember, but there's work to do before we start wondering about power! At least the rings are bedded in now and I don't have to worry about that

Idle manners are better, not perfect but much closer.

The brakes feel utterly ste, more bleeding perhaps in order, and a load of PS bleeding too, because they are terrible.

Will get some clips up at some point, it's time for lunch and a beer

[PomBstard]

Phew!! Enjoy the beer

[SturdyHSV]

Also seeing MAP drop with RPM, which would imply the intake is a restriction, drops from 101kPa down to 97 by 6400rpm...

May well need to look into a larger filter area.

[Polly Grigora]

SturdyHSV said:

It survived, the oil pressure isn't rising with revs as it should, so maybe oil pickup o-ring (very common to cock up) or something of that ilk

Do you mean it's rising to what it should be but slower than it should?

Good news that you made it to the rollers

I would have needed to take strong medication to numb the brain before driving the car as you have

[SturdyHSV]

Polly Grigora said:

Do you mean it's rising to what it should be but slower than it should?

Good news that you made it to the rollers

I would have needed to take strong medication to numb the brain before driving the car as you have

No sorry so it's about 35psi at hot idle, which is fine, but it's actually dropping to 30psi around 3k - 4k, and rises back up to 35psi at 5500 - 6000 say.

Rule of thumb stuff is normally 10psi gain per 1,000rpm, and yeah I'd really be expecting 55-65psi at high rpm.

Here's some video footage anyway, idle is still nasty (the good nasty...) and it sounds passable under load



To be fair it's still 420rwhp in the state it's in, which isn't 'bad' as such, but I'd definitely gotten my hopes up a bit with where it'd be on the first punt...

Could be as dumb as needs a new filter, not to be on break in oil, and just the oil pickup o-ring and we'll be back in the game, I shall get on with it and see where we end up. Good thing is I can at least pootle it around the cul-de-sac and I can heat it up and see what the oil pressure is doing without worrying about the rings now, so I'm in a better place than where I started this morning.

Also, I should correct above, the torque/bhp won't cross at 5252 because the scales are different between torque / bhp on the graph, missed that on first look.

With the filter restriction, it also went really rich (11.5:1 AFR) at 5,800rpm+ which isn't ideal.

Those brakes though, god they're a mess, I'll continue with this booster for a while but my initial impressions would fall foul of the name and shame policy I'm sure

It's a good company though with many happy customers so it's more likely mea culpa, more bleeding needed etc.

[Polly Grigora]

Appreciated, now understand

Sounds fantastic

[Oneball]

Oil pressure is weird, could it be the gauge?

[SturdyHSV]

Oneball said:

Oil pressure is weird, could it be the gauge?

Mechanical gauge was also reading low, so I think the sensor / gauge is accurate enough sadly.

It was still 35psi so unlikely any damage done, but obviously it's not encouraging!

[Samjeev]

SturdyHSV said:

Could be as dumb as needs a new filter, not to be on break in oil, and just the oil pickup o-ring and we'll be back in the game

Will be interesting to see what the outcome of the sump-off check is.
I ended up fitting one of those pickup tube braces myself, the ones that use the 2nd bolt hole that GM just seem to ignore. Not sure if it'll do anything but worth a short for some insurance.

[SturdyHSV]

Samjeev said:

Will be interesting to see what the outcome of the sump-off check is.
I ended up fitting one of those pickup tube braces myself, the ones that use the 2nd bolt hole that GM just seem to ignore. Not sure if it'll do anything but worth a short for some insurance.

Yep got one of those on too, agree seems odd GM just used the one!

Improved Racing brought out a windage tray for strokers about 5 days after I put the engine in, so this is probably a good opportunity to put one in

I did check the pickup clearance from the sump, but it's feasibly related to that, or the good old pump pickup o-ring, seemed to go in fine but with no experience of doing it, who knows.

I think I can probably lift the engine enough and drop the steering rack to maybe get it off, although access is going to be a right faff so may be more sensible to dump the coolant out too, get the rad etc out the way and make myself some room.

[Oneball]

Maybe the pressure is collapsing the oil filter and as it rises it’s pushing past the bypass so goes back up again.

[fred bloggs]

It’ll feel + one million when it has timing in it.
As for the filter restriction , I know a good solution :-)

I saw a black Ute coming out of Santa pod about 6 this evening, was it you?

I had a poor time there today, did an oil change before leaving, only put in 5 l as the dipstick was full. Kept going into limp on the strip. Didn’t take my laptop foolishly. Got home to discover it had a low oil pressure code, so guess it sloshed too much.
Found it strange as I usually put in over 6l

[stu vxr]

This thread has been one of the best I have read for a long long time with reference to our cars, love your determination Sturdy the debate has always been NA VS supercharged, being supercharged myself was the easy route to instant power, but if I would have had more funds being honest, I would have asked Monkfish to build me the ultimate NA engine.

Good luck with everything absolutely amazing sound, just not sure about the relocation of everything looks weird in the engine bay but the more I look at it I like.

Edited by stu vxr on Monday 16th May 19:08

[SturdyHSV]

Oneball said:

Maybe the pressure is collapsing the oil filter and as it rises it’s pushing past the bypass so goes back up again.

It's possible I suppose, it's a new Royal Purple filter, so at least a decent one and the same that I've used for a while... I'll be looking in the filter and things anyway, it's feasible the filter is a little clogged up if there was a lot of 'stuff' after the rebuild, rings bedding in and all that (or pistons eating themselves )

I'll look at the simpler solutions first anyway and go from there.

fred bloggs said:

It’ll feel + one million when it has timing in it.
As for the filter restriction , I know a good solution :-)

I saw a black Ute coming out of Santa pod about 6 this evening, was it you?

I had a poor time there today, did an oil change before leaving, only put in 5 l as the dipstick was full. Kept going into limp on the strip. Didn’t take my laptop foolishly. Got home to discover it had a low oil pressure code, so guess it sloshed too much.
Found it strange as I usually put in over 6l

Your solution is an excellent one, but for now I'd imagine a slightly larger OTR jobby would be a cheaper 'fix', after the oil pressure is understood.

Nope that wasn't me in the Ute, I'd had my car fun for the day by that point

Unfortunate with the strip time, saw you'd got a 13.2 which is great going, I really wanted to get a 12 before I did the cam in the Monaro, but didn't go to the Pod much and most of the time the track was so slippery I just had to launch at idle and baby it. The one time it was actually a little grippy (could slip the clutch with some RPM to get going) and I managed a 13.18, so sadly not quite the 12!

stu vxr said:

This thread has been one of the best I have read for a long long time with reference to our cars, love your determination Sturdy the debate has always been NA VS supercharged, being supercharged myself was the easy route to instant power but if I would have more funds being honest I would have asked Monkfish to build me the ultimate NA engine.

Good luck with everything absolutely amazing sound, just not sure about the relocation of everything looks weird in the engine bay but the more I look at it I like.

Cheers, yeah realistically supercharged is probably objectively better day to day in most ways, yeah maybe heatsoak is a factor and I suppose it's a bit more complicated and more weight, but there are far fewer compromises that you encounter day to day than with an even vaguely equivalent NA build. And if you're paying for the labour, NA is a LOT more expensive

The cleaned up engine bay is me realising an image I've always had in my head of what a muscle car engine bay looks like, or at least, as close as I'm likely to get the Monaro with my current skills!

Subjective matters aside, certainly if you've ever changed the plugs on one, you'll appreciate the improvement in access getting rid of that ABS bracket has made

In terms of next steps, I'm still in a bit of a fog mentally as to what the next step will be as there's a lot of thoughts floating around, I think it's time to write things on the whiteboard again

I will need to put the car back in the garage, get the bonnet and bumper off for access, up on the quickjacks, and lift the engine up as high as I can with the crane and see what clearance looks like between sump and subframe, most likely drop the steering rack down as well.

I think it's unlikely I'll be able to get it out, but I'll have to do those steps anyway to get the subframe off, so it won't be wasted effort.

I'll likely pick up the Improved Racing windage tray at this point, it means I don't have to use the shimmed factory windage tray (to clear the increased stroke), which whether I like it or not will have put the pickup tube closer to the sump bottom. I measured this clearance and it was within tolerance, but it's something I've now got the opportunity to improve as the sump is coming off anyway, so no point not doing so...

It's obviously a silly flywheel estimate, but I have to also remind myself that 520lb ft is a decent torque figure, it works out as around 1.3lb ft / ci, which is actually fairly decent for a 'street' engine, so hopefully the thing is actually pretty healthy once everything is working as it should be!

[SturdyHSV]

Have been speaking to Tony Mamo about the results, and he's come up with a sensible conclusion...

Long story short, working theory is I need a high volume oil pump.

So, when originally speaking to Tony and speccing things, he asked what pump I had, which was a Melling 10295. This is basically a stock replacement with (ironically) 10% higher pressure.

At the time, we were going with the Johnson short travel lifters.

During all the covid mess, manufacturing in America was in a right state, and car parts were no exception. Johnson were 6 - 9 months back ordered, and naturally as they began to get back up to speed, they focused on the fancier stuff first... So the short travel lifters with axle oiling were available, and so I went for them.

At this point, I gave no thought to the addition of 16 more little oil holes to the oil demands. In addition to this, I'm running that oil cooler with some fairly chunky lines to it, which again, typically would require more volume from the pump.

There's some internet shouting about higher volume pumps draining the oil pan, I've found one example of this in the UK by someone who I know isn't an idiot, so that is a minor concern, but have also spoken to Luis who tuned the car, Tony who has built / specced more engines than I've had hot dinners, and Improved Racing in the states who have all given opinions that reassure me I'm going in the right direction.

Special mention should go to Improved Racing, whose sump baffle, oil cooler adapter, billet oil barbell, and soon crank scraper and windage tray I'll have, I asked them what they thought to the 'drain the pan' internet talk about high volume pumps earlier on today, and I've just received an absolutely enormous and thorough e-mail from the founder / president of the company explaining a vast amount about their thoughts, what they've seen in testing etc. Remarkable customer service. All their instructions are spot on, and their products seem really high quality, so I'm a bit of a fan for life I think

I shall load up the "while I'm in there" parts cannon and get this thing back on the dyno.

[SturdyHSV]

So, the plan (this is mostly for my own benefit), aside from waiting for parts / tools to arrive...

Tidy up garage / workshop (it's in a st state after the flap of getting ready for the dyno).
Car in garage and back up on the quickjacks where it belongs
Take front end off
Drain fluids, take radiator etc. out, pull the plugs out for a look
Take belt, water pump and crank pulley off
Support engine from above
Drop subframe down out the way, may require disconnecting some bits (the engine at least...), we'll see
Had a genius idea to lower the engine at this point so I can put that driver's side rocker cover on
Take sump off
Generally 'inspect' with my inexperienced eye, likely remove pickup tube and windage tray in preparation and for better inspection
I'm weighing up popping a rod cap off to inspect the bearings
Front timing cover off, oil pump off

Reverse the list, verify new oil pressure and get a dyno session booked to send it properly

[fred bloggs]

How low does the oil pressure get ? a little porting on the
outlet of the pump and a heavier spring in the relief valve may be enough, presuming its not a pick up issue.

https://www.youtube.com/watch?v=xfjsyo2AhiY

[Krikkit]

Just catching up on the thread as I was away over the weekend etc - looks absolutely splendid.

Sounds like the right solution getting an uprated oil pump thrown at it, not worth the headache of constantly worrying about it.

[SturdyHSV]

fred bloggs said:

How low does the oil pressure get ? a little porting on the
outlet of the pump and a heavier spring in the relief valve may be enough, presuming its not a pick up issue.

https://www.youtube.com/watch?v=xfjsyo2AhiY

I'll have to recheck the logs, but hot idle was 35psi ish, which makes a pickup issue seem unlikely. Cold idle was 45psi ish and would flare instantly to 55psi ish with 2,000 - 3,000rpm on, again making pickup issue less likely (but by no means impossible).

Also worth considering is the oil cooler is not in the circuit during 'cold' idle, as the thermostat for it opens at ~85*...

During actual hot runs, it would drop down to 30psi ish around 3,000rpm ish, and climb back up to 35psi ish at 5,000 - 6,000.

We only went to 6,000 three times, will have to find out whether that turns out to have been a mistake.

Yes arguably I could just loop the lines to the oil cooler to keep it out of the circuit and see what happens, but that doesn't seem like a suitable 'fix'.

Krikkit said:

Just catching up on the thread as I was away over the weekend etc - looks absolutely splendid.

Sounds like the right solution getting an uprated oil pump thrown at it, not worth the headache of constantly worrying about it.

Certainly I can (with hindsight) find plenty of evidence that the axle-oiling lifters need a high volume pump. With just the oil cooler it seems one can get away with just the higher pressure one (the 10295 that I have), or maybe even just a stock one with the tight factory clearances keeping pressure up, but it seems pretty standard that if people are using the axle oiling lifters, they're also using the high volume pump.

[SturdyHSV]

I've been doing some pondering about this 'drain the sump' stuff that seems to get trotted out whenever high volume pump is mentioned.

I found a graph on Improved Racing's website. Admittedly it comes from Melling, who sell oil pumps, but I figure it's close enough... If anything, it'll make the Melling look like it flows more than it does, and the GM flow less than it does, which is actually ideal for what I'm trying to work out.



So we have a rough idea of pump volume in (presumably US) gallons per minute, but we don't know the rate that the oil can flow back down to the sump to keep the level high enough for the pickup to be submerged.

However, nobody has ever suggested the standard pump could drain all of the oil from the sump, and I think it's safe to assume that at some point in GM's durablity testing, an engine will have been run for a very long time at high rpm.

So I think it's a fairly reasonable assumption that the rate of oil drain back into the sump is enough to support the sustained peak flow rate of the standard pump basically indefinitely, which looks to be about 6.7GPM at 6,200rpm....

This doesn't seem unreasonable, hot oil will flow like water, and 6.7 US gallons is about 25 litres, so you're only talking about ~420ml a second of oil flowing back down through the engine.

For the sake of making it a worst case scenario, let's assume 420ml per second is some sort of absolute hard limit, and that more oil or higher pressure won't increase that rate of return.

It looks like the 10296 can sustain 8GPM. I'm sure this is optimistic best case from Melling, so it's probably less as mentinoed above, but we'll take it as it states.

8 (US I assume) GPM is basically 30 litres a minute, or 500ml per second of flow.

So now we have 2 nice simple numbers to work with. Assuming I sat at 7,000rpm, I'd be pumping 500ml per second 'up' into the engine, and only 420ml per second would be draining back down in to the sump. So I'd theoretically be losing 80ml per second of oil from the sump. The sump holds over 6 litres, but naturally needs some in there to actually cover the pickup (which sits ~0.300" off the base of the pan). So let's go worst case again and (ridiculously) assume it requires over 2 litres to cover the pickup, leaving only 4 litres to play with.

With 4 litres of 'spare' capacity if I was losing a theoretical 80ml per second gives me 50 seconds at 7000 rpm before it could, in an excessively worst case, uncover the pickup.

Naturally g-forces will play a role, although the sump baffle is trap doored etc. but high loads could slosh what's left in the pan away from the pickup, especially if one manages to maintain 30 seconds or so of peak flow from the Melling to theoretically lower the level a bit.

It's also worth keeping in mind that if that 420ml/s is a hard limit of oil return to the sump for whatever reason, then at any point about ~4,000rpm the Melling could be out pumping what can be returned, although obviously in much smaller amounts.

It's interesting, I think working with that hard 420ml/s limit, I could envisage how given enough time spent at high rpm and likely with G forces involved too, it could eventually lower the level enough to expose the pickup, although I think the hard 420ml/s limit isn't a particularly realistic scenario, it'd have to be storing these litres of oil somewhere 'up' in the engine in a location that meant it didn't drain back any quicker.

The much bigger 10355 pump I can see how it could actually be a problem. It flows more at 2,000rpm than the standard one can flow at its peak. It's very reasonable to assume that a car could sit at 2,000rpm for an hour cruising along a motorway. If the rate of flow back to the sump isn't able to keep up (which is the really big unknown) then I can see how the 10355 could cause issues.

That's a lot of text. Here's a picture of a clean Monaro obviously immediately covered in tree bits.

Edited by SturdyHSV on Friday 20th May 13:40