DC's 1756VK-assisted B4

According to the Victor-Reinz catalog, a 1-hole ARL HG is the same thickness as a 1-hole 1Z HG which is 1.45 mm. The AAZ HG's start at either 1.6 mm or 1.53 mm. Guess the AAZ's get squished more?

The very first thing you should do is check the calibration of your measuring tools. The second thing I would check is your reference surface- is the block deck flat? Then I would measure all over the top of your piston to be sure you are measuring the highest spots on the piston. All very basic and you may have done this.

Did you verify the pin height of your new pistions to the pin height of the old pistions?

Digital Corpus said:

I measure all 4 points of the pistons closest to where the valve reliefs break the side wall of the piston, i.e. closest to the wrist axis.



This head gasket very much looks identical in layout to the 1Z. Just my 2 cents.


Easiest being subjective. I'd have to replace the bolts for the main bearing caps and the con rods and tear everything down and get it back to a shop. Thats another week of down time of just waiting, no offense. A 1-hole 1Z gasket is on order regardless. but if the CR difference or performance difference is that significant (eye-ing Jon's experience) then I could switch in a few months to a 1-hole AAZ if those photos hold up true.

Any additional/continued ideas welcome.

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Digital Corpus said:

This head gasket very much looks identical in layout to the 1Z. Just my 2 cents.

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The IDI gasket should have sealing ring around the precup since the precup isn't flush with the head. The precups are made from Iconel so they expand at a different rate than the aluminum head. That picture definitely shows a gasket missing that sealing area but most of the IDI gaskets I've ever seen in real life have had it.

The actual cooling and oil passages are the same though, you can put an AAZ head on a 1Z / AHU block.

I believe I made a mistake - the 1 hole piston protrusion is 0.91-1.00mm. What I referenced in Post 173 was a mistake (I was looking at the head gasket thickness). So you'll only be ~0.5 to 1.0 point short on compression, not ~3.0 as I thought before. This assumes that the 1Z Head Gaskets generally follow the ALH/ARL thickness which from what you found in the VR catalog is true.

The ARL and ALH pistons share the same wristpin to top of piston height and valve relief depth which is why I used that as a reference on my build. Do your original 1Z/AHU pistons have the same wristpin to top of pistion dimension as the ARL's?

Being ~1 point short on CR isn't the end of the world, but it's still not great either in my opinion due to the increased squish volume.

I don't follow the discussion about the AAZ IDI head gasket - how is that relevant here? I though the engine build was a 1Z/AHU?


Sorry if my mistake caused any problems for you - hopefully you get it figured out.

Rereading jfettig's post with the .032 protrusion he found and the .036 protrusion he built to matches the .032/.033 protrusion you measured in your short block. Suspect your plan to button the engine together with the 1 hole 1Z gasket is sound. If I had the measuring tools, I would check protrusion on the stock short block in my garage. Guess I could use an old set for spark plug feelers to measure .030/040 deck height. But can not remember last time I gapped spark plugs or adjusted mechanical lifters for that matter.

FUB, don't worry about it. We're all human here. Heck, I've made a few mistakes during this build. Anyhow, I ran my math again. I've previously assumed that piston bowl volume is the sole reason for the CR change. I should get some wax or oil and play around with filling the bowl volumes, but that's for another time. Anyhow, this is how I checked that assumption:

The following calculations assume a piston mates a cyl wall with no clearance and that the piston head is perfectly flat, i.e. there are no valve reliefs.

In ideal terms 474 cc cyl. vol. is compressed down to 19.5:1, aka 24.31 cc
The ARL bowl volume is 24.6 cc and ASV's are supposed to be stock CR and are 23.54 cc
This means that with a 19.5:1 ASV build, squish volume is ~0.77 cc
Enlarge cyl by 0.5 mm, increase bowl size to 24.6 cc, and the new compressed volume is 25.38 cc
An 80 mm cyl with a 95.5 mm stroke puts us at 480 cc
This computes the CR to 18.9:1

At the lowest, my pistons are 0.17 mm too short. I'll round this to 0.15 mm
At 80 mm diameter, this is a volume of 0.754 cc
Add this to the 25.38 and we have a compressed volume of 26.134 cc
The computed CR is then ~18.37:1.

Since the bowl volume alone doesn't account for the drop in CR, it has to come from somewhere else. On the 80 mm ARLs, the valve reliefs cut through the piston crown, which will drop the CR. Though the first piston ring is lower, this volume difference accounted for 0.05 cc, neglible. So, with some assumptions on where the additional volumes comes from to drop the CR to 18.5:1, assuming this figure is correct despite evidence to the contrary, it appears that I'm in no danger of a CR lower than ~18:1. Since the valve pockets have the majority of volume in the squish space of the combustion, I'm now not too worried about just a little extra up top. Especially given Jon's numbers.

Long story short, head gasket isn't doing much to drop CR if a little math is applied to show a simplified version of what is going on. Speaking of which, I was told the wrong time of when the gasket should get in: tomorrow about noon, not this morning around 9 am.

The old Club adage of drive more, worry less applies here I guess. Oh, and ignore all IDI/AAZ HG nonsense.

I have some recent family business that has taken priority. I won't be posting any updates until the car is drivable for the sake of my sanity.

I gave up on sanity years ago. It's much easier.

I'm still taking photos of various pieces of work as I complete them and I'll post them up at a later date. I've opened up the compressor outlet of the turbo, refined some piping. Got the orb of death secured back on the head, et al. I'm taking some measurements of the oil cooler though. Despite the other option for a larger cooler, I'm kinda married to the larger oil filters especiall since I bought a 12 pack a couple years ago and we still have 4 or so left. Maybe in the future I'll revisit this upgrade option. I've taken measurements of the critical parts before putting it back together. Either way, The head is fully installed, the intake and exhaust manifolds are on along with the turbo. Oil lines are plumbed, though they do need tweaking at a latter point in time. Anyhow, the engine is back on the hoist, off the stand and I'm having a dinner break.

Speaking of oil, how can I prime the system, not the least of which is the turbo? This is bit of a quandary for me as I don't want to just turn the engine on and have the turbo spin with no supply for 5-10 seconds.

I bought an oil pump drive I can run from a drill. It's just a piece of bar stock with a slot cut in the end of it. Yank the vac pump, run the oil pump, ta da.

Sent from my HTC One XL using Tapatalk

^^ This will work best, especially if the oil galleries are dry.
If you are only worried about the turbo, I had good luck with using a syringe
(a turkey baster works, too) to inject oil into the line until the turbo was filled
and then connecting the line and starting 'er up.
Good luck, DC!

Thanks guys. Gotta pick up bolts for the pressure plate tomorrow and then reconstruction will continue. Flywheel is torqued down so its a good place to stop. Used part of the engine stand to bolt to the block and have a stud of the FW get locked in the other hole as a counterhold, similar to what's shown in the Bently. Anyhow, it's a good place to stop for the night.

vanbcguy said:

I bought an oil pump drive I can run from a drill. It's just a piece of bar stock with a slot cut in the end of it. Yank the vac pump, run the oil pump, ta da.

Sent from my HTC One XL using Tapatalk

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flee said:

^^ This will work best, especially if the oil galleries are dry.
If you are only worried about the turbo, I had good luck with using a syringe
(a turkey baster works, too) to inject oil into the line until the turbo was filled
and then connecting the line and starting 'er up.
Good luck, DC!

Click to expand...

I'd like to christen the aforementioned idea as "Oil Pump On a Stick". diagnosed bad washers right off the bat. I had an interruption of some bad threads earlier. I'm about to transfer the engine + trans to the sub-frame.

An old trick to run the oil pump with a power drill. Get a round wooden dowel carve/cut a one end into a straight screw driver like end. Put this end into the oil pump drive gear, the other end into the drill chuck. Use the drill to turn the oil pump.

I had spare 3/8" aluminum rod left and made a notch in it for just that. Need to clean the oily sludge off the subframe + power steering and then I'll transplant the motor + trans. I had two set back with some problematic threads and washers which cost me 2 hrs. If I had those two back, I know that the final checklist items of bolting in the subframe, priming fuel, connecting IC pipes and just putting the front end back together would be the last things left.

john.jackson9213 said:

An old trick to run the oil pump with a power drill. Get a round wooden dowel carve/cut a one end into a straight screw driver like end. Put this end into the oil pump drive gear, the other end into the drill chuck. Use the drill to turn the oil pump.

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Clockwise or counter-clockwise?

Clockwise

When everything was torqued down in the block


Used 3/8" aluminum bar stock for guide posts


New oil line - Think I might have to get another one made but 1/2" shorter





Drilled out 2 of the 3 suggested holes for letting oil drain from the 5th gear. I let the current oil supply push out the filings, though I still need to drain the rest of the fluid.


A couple blocks of wood later I got the trans aligned and mounted


Where I left things last night

Special thanks to temporator and swtlowtdi for helping me get the subframe in. Having one person in the cabin for the steering column alignment, one on the hydraulic jack, and another underneath for the rear bolts and the bolts that go through the rear LCA bushing makes the process a whole lot easier. I wish I had my old work schedule so I could stay up late and the three of us get the engine back in, but that's not the case. My hat is off to you two for the help.

Digital Corpus said:

Special thanks to temporator and swtlowtdi for helping me get the subframe in. Having one person in the cabin for the steering column alignment, one on the hydraulic jack, and another underneath for the rear bolts and the bolts that go through the rear LCA bushing makes the process a whole lot easier. I wish I had my old work schedule so I could stay up late and the three of us get the engine back in, but that's not the case. My hat is off to you two for the help.

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No problem. Go back to working nights, we would have been done tonight!

Looking good!

Did you decide that the piston protrusion was basically a non-issue or did you have to do something about it?

Mark

Great progress sir! I am jealous you are doing fun things to yours, and mine sits in the corner collecting dust.

Likewise, I too am jealous. But, until I can find a parts car, mine will have to sit.
Oh, to have fresh engine done right with extra fun factor (read torque)!

Tony

very well done guys !

I don't know if I'd bother getting the line shortened.1/2 inch might be too much ?

markd89 said:

Looking good!

Did you decide that the piston protrusion was basically a non-issue or did you have to do something about it?

Mark

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Yup, I considered it a non issue. The goal with the ARL pistons was to drop CR a bit. This 'helps' that but is equivalent to shaving off the top of the piston a little bit. That being said, Jon's B5 1Z engine had similar protrusion numbers when he pulled the head on his engine, so I decided to just put it together.

psst1997 said:

Great progress sir! I am jealous you are doing fun things to yours, and mine sits in the corner collecting dust.

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TonyJetta said:

Likewise, I too am jealous. But, until I can find a parts car, mine will have to sit.
Oh, to have fresh engine done right with extra fun factor (read torque)!

Tony

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No need to be jealous. This 2 week project is 2 months old I jumped the battery with a 10 amp charge until full and then trickled it on 2 amps until full 2 days ago just to make sure it didn't die on me. It was done charging in about an hour or 2.

Anyhow, I'm writing this post from work, but remoted into my server and running a browser that way. Traffic is a bit too heavy to drive home and my legs and back are still sore. I *might* attempt the engine tonight, or wait another day, but I haven't decided. The anticipation for a running engine is palpable...

Last night we hoisted the k/sub-frame into the street and cleaned it then went back into the garage to get the finer details cleaned (remember the oil leak?) so that took time. Then we cleaned up the engine bay and I added the foiled sound deadening, which I forgot about. *shrug*

andy2 said:

very well done guys !

I don't know if I'd bother getting the line shortened.1/2 inch might be too much ?

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Heh, I'll post better pictures of this later and you may change your mind .

D.C. What kind/brand of foil sound deadener? Foil covered Mass Loaded Vinyl?

Engine is in and secured to all but the trans mount.

andy2 said:

very well done guys !
I don't know if I'd bother getting the line shortened.1/2 inch might be too much ?

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That's what I like about the build-it-yourself lines; you can pre-assemble the hose and shorten it 'til it's just right.
Good to see it coming together, DC!

Is it running yet?