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klipless
klipless Reader
8/30/17 8:26 a.m.
fidelity101 wrote: next move onto the crank, so I remove the gear with a 3 jaw puller and then notice this...

Is that a crack at the base, or something else?

Chadeux
Chadeux Dork
8/30/17 8:40 a.m.

In reply to klipless:

I read that it was a casting mark. Without being there to pick at it, I'm inclined to agree with him.

mazdeuce
mazdeuce MegaDork
8/30/17 8:56 a.m.

These changes at the front of the motor are to get it to play nice with the electronics currently in place, yes? Any thoughts on the easiest/best way to go if starting with bare frame rails and no emissions? Is one generation of computer better for any reason?

fidelity101
fidelity101 SuperDork
8/30/17 10:01 a.m.

In reply to klipless:

its a casting mark, everyone on FB blew up when I posted it in a group it became totally useless discussion after that, the camera likes to pick up the shadow and make it look like a crack in photos, in person its clearly a casting mark.

mazdeuce wrote: These changes at the front of the motor are to get it to play nice with the electronics currently in place, yes? Any thoughts on the easiest/best way to go if starting with bare frame rails and no emissions? Is one generation of computer better for any reason?

Correct. The ECU/Wiring differences between the L18s half generations is basically identical. The problem is that the gen 3 electronics use the CKP at the back of the engine and the cam sensor is only a 1x count wheel. The gen 4 electronics read a 58x for crank and 4x for cam.

If you're putting an L18 into like an old K5 or your international... you have 2 options the 00-03 which has EGR (which you can delete) and return style fuel rail (which you can swap) but if you keep the return rail, the regulator is adjustable and apparently these things like higher than normal fuel pressure. Also the earlier engines have press in wrist pins so they tend to slap like the early LS LQ engines, the 04+ have floating pins like the gen IV motors. A few small changes to the intake manifold/gasket for robustness, slightly different cal. etc etc - there are some out there that are DBC not DBW if you get them old enough.

here is an IN DEPTH comparison of the years which is helpful and also have some good part number references for running different accy drive if you have frame clearance issues or wanna run AC in an old CK truck.

8.1 Resource thread

also if you have an old blazer/burb/ck-truck this place is a goldmine and I highly recommend paying for the subscription for a few added benefits of image hosting and viewing/posting.

Chadeux
Chadeux Dork
8/30/17 10:09 a.m.

In reply to fidelity101:

I just want you to know that thread was funny from where I was sitting.

fidelity101
fidelity101 SuperDork
8/30/17 10:13 a.m.

In reply to Chadeux:

Yeah as soon as I saw the 1st comment, I was like awww hell - just grab the popcorn I guess...

Chadeux
Chadeux Dork
8/30/17 10:30 a.m.

In reply to fidelity101:

Yeah I'm in that group almost exclusively for meme friday. I don't think any serious discussion ever actually goes as planned.

fidelity101
fidelity101 SuperDork
8/30/17 1:53 p.m.

NEWEST BEST IDEA!

instead of drill/tap the crank gear/wheel...

I wonder if I need to shorten the harmonic balancer, because with the increased thickness of the new crank gear + the thickness of the reluctor wheel, will the balancer be too long sticking out too far and causing the accy drive belts to be out of alignment?

So if this needs to be machined/modified anyways... while its in there get a groove cut in the balancer for a key which will then get a key installed to go through the unmodified wheel and into the unmodified crank gear through the existing key slots.

The harmonic balancer has witness marks from being pressed onto the existing crank gear, so with that it will be easy to tell where to cut the groove.

mazdeuce
mazdeuce MegaDork
8/30/17 3:26 p.m.

In reply to fidelity101:

I've read that guy's build threads on Pirate. His knowledge of what fits where and why is amazing. I can't even remember which oil filter my truck uses without Google.
Thanks for the link, there's a reasonable chance I'll need it at some point.

fidelity101
fidelity101 SuperDork
8/31/17 9:11 a.m.

In reply to mazdeuce:

yeah I find myself frequently checking that thread for something or another.

anyways I yesterday I tried making a woodruff key for it out of a much larger one and it works but I don't have high confidence in it, because its just so small. next step is just glue that to the wheel to aid in alignment then drill the wheel/gear for a rollpin that will be flush with the surface.

fidelity101
fidelity101 SuperDork
9/1/17 12:36 p.m.

Holiday weekend is about to begin and the truck is ready to be torn apart!

gonna be a fun weekend of discovery. At least nothing here is rusty and everything comes apart with ease, HOPEFULLY everything else goes well.

the plan is to remove the front core support entirely and work on everything up close and personal. Also I don't trust my cherry picker to pick the engine up that high, seems scary. better safe than sorry! plus if we have to fabricate anything it should be easier.

and no the whole floor isn't coolant, I did spill a bit but I mopped the floor a bit but I didn't want to wait for it to be dry to take the photo lol. Best way to keep good coolant is to put large cork plugs in the radiator hoses, works great for temporary storage.

fidelity101
fidelity101 SuperDork
9/3/17 4:59 p.m.

Got the engine out Saturday and test fit the big block. Many general assumptions are discovered to be true so with the right combination of OEM parts - this might literally bolt in. The only issue is adapting the engine electronics which is very manageable.

Also people always say that the big blocks burn oil no matter what between oil changes, well I think I figured out why - its because they have no PCV system... I think I may add one or use what the 6L had and adapt it.

crankwalk
crankwalk GRM+ Memberand Dork
9/4/17 12:14 a.m.

Good luck! Can't wait to see you pull this off.

And yeah I bet adding a PCV would help. I always just thought they had bigger tolerances/clearances and naturally burned oil. Maybe a PCV and a catch can.

Patrick
Patrick GRM+ Memberand MegaDork
9/4/17 10:07 p.m.

So when can I have the 6.0 for a challenge car

fidelity101
fidelity101 SuperDork
9/5/17 3:04 p.m.
Patrick said:

So when can I have the 6.0 for a challenge car

1000 dollars you can have the 6.0 with accys (minus AC and alternator) with a gen 3 harness/throttlebody/L18 injectors. Just needs a rod bearing - polish the crank and go.

Will trade for rx7 parts of course :)

fidelity101
fidelity101 SuperDork
9/7/17 1:05 p.m.

I was waiting for the dust to settle from the madness of this weekend’s wrenchfest before I could finish the update post, digest the situation etc.

Pulling the engine was fairly straightforward newer vehicle had no rust so that was nice. I learned a few tricks so if you are ever removing an engine from a modern chevy truck these should help.

If you remove the core support, you do not need to remove the hood but you need to loosen one fender so you can move it inboard/outboard to get the core support out. I see the people at duraburb pick the whole body off the frame to do their swap which would be a great idea too but I don’t have the equipment to do so or the space.

 By far the hardest part is the bolt for the bellhousing at top dead center. You will need a few feet of various extensions and ideally 2 to 3 u-joints with a medium well (deep works but a medium one would be best)  socket. The problem is that the cab  comes together near there as 2 stamped pieces of steel spot welded together which tends to hang up on the u-joint when trying to remove the bolt. When you remove the engine, beat this with a hammer inward so you have that extra 1” of room to turn a socket for reinstall because the area is a tight fit. If you have a 1” bodylift you won’t need to do this at all and everything will be a little easier. I kind of want to do one now actually…

Then Loosen the trans crossmember bolts, support the pan or bellhousing with a floor jack.


Now that you have removed the bellhousing bolts To get the engine out you need to lower the front axle about 2” so just remove the bolts attaching it to the frame on the passenger side and the big eyelid bolt at the top. You can let it hang but I lightly supported it with a floor jack.

 

Then with the engine out, clean everything! I have a pretty bad power washer but it managed to take the grime and paint right off the frame to bare metal! I hate working on oily grimey parts, it always makes it much worse. Kind of surprised this much came off, makes me think it wasn’t applied very well when the vehicle was built.

So now I gotta paint it and let it dry, meanwhile I will prep the engine for install back into the chassis but before I can do that

Meanwhile I test fit the engine to see if it physically fits in the cab and managed to put a few bellhousing bolts in to see, and it fits better than the 6.0 the intake manifold isn’t a mile tall. The rumors are true. These HD frames are the same from 2000/2001-2013 so mechanically this bolts in.

The engine mounts and engine mount plates are unique between the big block and small blocks. However the big block shares the same engine mount and mount plates between the 6.6 duramax – and they did offer the Duramax throughout the GMT900 lifespan and backs up the claim that Duramax engines were designed by chevy instead of like a cummins in a dodge where they just told ram to piss off and make their engine fit because we won’t change ours.

So with the right engine mount and mount plate this bolts in, bellhousing bolts up – everything is pretty cut and dry GM parts bin. Here is a side by side between the two

If you don’t want to use the big block mounts/plates – you can always fab your own but I prefer the easy button method. Otherwise if you use the small block stuff MOST of the bolt holes line up so it wouldn’t be too hard but definitely not worth it when there are thousands of junk trucks around. But as you can see they are pretty similar.

fidelity101
fidelity101 SuperDork
9/7/17 1:06 p.m.

So that being the hardest part we start then moving to the other compatibility items:

  1. Alternator – swaps right over.

  1. Oil pressure sensor – electrically the same and just a different thread style so this literally plugs in! (as shown below) the connector fits, may not be the exact one but it’s a tight fit and robust fit for sure.

  1. Injectors – not sure how different they really are (aside from obvious electrical hookup) but they fit on the L18 rail no problem and that’s all I cared about. Again the goal is to keep it as close to original as possible to minimize any elaborate custom software reflashing.

The next big item (literally) is the radiator. They are different between the 6.0 and the 8.1. the 6.0 is common between GMT800 and GMT900. The inlet/outlet are a little larger on the 8.1 and the core is physically larger (~10%) but the other issue is that the oil cooler lines for the engine oil are much larger.

I’m afraid of making a line adapter to avoid changing the oil characteristics/flow etc. The 8.1 I think needs the 8.1 radiator then the coolant hoses all make sense and bolt together so I can have heat to the heater core and no hose looks spliced and out of place. Problem is with the 8.1 parts cost more for no good reason other than volume on sales is much lower than the LS stuff. 6.0 HD radiator is 160 bucks, 8.1 is 330+. LS engine mount is 45 bucks, 8.1 engine mount is 90. Notice a trend? But anyways if I just man up and order the 8.1 coolant system (essentially) everything will bolt up. The trans cooler line fittings are the same for both the 8.1 and 6.0 so that’s plug and play for me at least. Because the engine is larger the fan shroud is smaller, I believe the clutch fans will bolt on interchangeably but I will find out for sure. Essentially the 8.1 coolant system is unique to it but the chassis isn't and this being a GM era of economic decline the accountants there figured you just need to make as much stuff common or interchangeable as possible and it became a brilliant manufacturing strategy to cut costs.

 

Still lots to do though – white board helps you stay on track or remember things.

With the engine out I will prep the wire harness so I can access everything easier then bolt everything together. Still a few more things to adapt and likely a few wire extensions. Once I figure that aspect out entirely I will post the modifications required.

 

mazdeuce
mazdeuce MegaDork
9/7/17 3:05 p.m.

Does that say Mach shop run? Without a number I assume you mean Mach 1, but that's still an impressively fast shop run. 

fidelity101
fidelity101 SuperDork
9/7/17 3:14 p.m.

In reply to mazdeuce :

machine shop run :) Due to the added thickness of a new reluctor wheel and the slightly thicker crank gear I need to remove material from the harmonic balancer so the belt drive aligns properly. I could probably do it myself but I figure something like that would be easier and better if done by a shop.

I am also thinking of taking the gear off and having a rollpin setup for the reluctor wheel.

I have made a woodruff key for it out of a spare rx7 woodruff but I don't think its too big so I will be going for the belts and suspenders approach. But I may be able to hand that portion by myself.

 

 

fidelity101
fidelity101 SuperDork
9/10/17 8:06 p.m.

They stopped offering the suburban in 3/4 ton in 2013 - since then its been half ton trucks only fort his body style, then since Chrysler and Ford don't have any big blocks anymore, this is literally the last of the big blocks :O

 

/que madmax music

 

anyways...

 

I managed to get some work done this weekend. I painted the frame and while I let it dry I was able to get a few things sorted out to prep the engine for re-install. Swap the fuel injectors over and re-install the rail and drop the oil pan to clean it a bit, some sludge at the bottom but nothing crazy.  And foremost was to tackle the robustness of the reluctor wheel install.

After much debate I went with a roll 1/8” roll pin, however I had made a very small woodruff key from another key to help locate the wheel correctly on the gear so I could drill the hole for the pin in the right location.

The gear was deep enough that I didn’t need to drill all the way through but a standard size hardware store roll pin would work fine:

Here is it completed, all that’s left is to re-install the cover and install the crank pulley and oil pan.

I haven't done that part yet because I need to shorten the harmonic balancer by 3.5mm because of the added thickness of the reluctor wheel (2mm) and the thicker crank gear (1.5mm) so that the belt drive is aligned, otherwise it will be 1 to 1.5 ribs off and that will want to toss a belt. Need to do a machine shop run and have that turned around quickly before I can proceed. You CAN PROBABLY do this part yourself with a grinding disc or file but I'm gonna opt to have this done with higher accuracy and be confident that its flat and straight.

camaroz1985
camaroz1985 Reader
9/11/17 8:33 a.m.
fidelity101 said:

They stopped offering the suburban in 3/4 ton in 2013 - since then its been half ton trucks only fort his body style, then since Chrysler and Ford don't have any big blocks anymore, this is literally the last of the big blocks :O

 

/que madmax music

 

anyways...

 

I managed to get some work done this weekend. I painted the frame and while I let it dry I was able to get a few things sorted out to prep the engine for re-install. Swap the fuel injectors over and re-install the rail and drop the oil pan to clean it a bit, some sludge at the bottom but nothing crazy.  And foremost was to tackle the robustness of the reluctor wheel install.

After much debate I went with a roll 1/8” roll pin, however I had made a very small woodruff key from another key to help locate the wheel correctly on the gear so I could drill the hole for the pin in the right location.

The gear was deep enough that I didn’t need to drill all the way through but a standard size hardware store roll pin would work fine:

Here is it completed, all that’s left is to re-install the cover and install the crank pulley and oil pan.

I haven't done that part yet because I need to shorten the harmonic balancer by 3.5mm because of the added thickness of the reluctor wheel (2mm) and the thicker crank gear (1.5mm) so that the belt drive is aligned, otherwise it will be 1 to 1.5 ribs off and that will want to toss a belt. Need to do a machine shop run and have that turned around quickly before I can proceed. You CAN PROBABLY do this part yourself with a grinding disc or file but I'm gonna opt to have this done with higher accuracy and be confident that its flat and straight.

The do now have the 1 ton Suburbans, but supposed to only be for government and fleet vehicles, however if you look on Autotrader, etc. there are several on there for sale.  Of course I think they start around $80k, and because they are intended for limo service or armored car service have a towing rating of only 3500 lbs.

That said, I like your project, and am excited to see it all together and running.  Maybe you already said this, but are you going to maybe throw a cam in it before you put it all back together?  Now would be the time.

fidelity101
fidelity101 SuperDork
9/11/17 9:42 a.m.

Yeah those are few and far between and they do come with the big block apparently or the 6.6. I also heard a rumor you can still buy the excursion in Brazil as a new vehicle but I don't live in South America...

I would really like to do a cam and a rocker ratio change but I just don't have the budget or timing for it right now. I'd be curious to see how this performs at a stock level with the 6 speed as compared to the LY6. I want to get this driving and capable for October's LSPR rally event. Either towing or just commuting/camping in it - I don't want to pull the intake, rocker arms, pushrods, and lifters etc. The cam swap really impacts my timing right now. If I undergo a cam swap I am sure I will spend an additional 2 weeks which is something I don't want to do. I am still on the fence about switching to the 1.7 ratio roller rockers from Raylar, they fit under the stock valve cover and it doesn't seem like a super invasive task, they gain 18hp over stock.

I'm also not comfortable tearing into the engine's long block. I can build rotary engines fine I just can't put together a pushrod v8 for the life of me...

fidelity101
fidelity101 SuperDork
9/12/17 8:00 a.m.

 

Not much I can do now, just waiting on parts to arrive (and come back from the machine shop) – I might have clicked a few wrong clicks so it’s taking a few days longer than anticipated to continue the progress. So until brown santa arrives  I managed to paint the frame.

fidelity101
fidelity101 SuperDork
9/12/17 9:56 p.m.

 

Here is the woodruff key I made that would make it flush with the reluctor wheel installed on the crank gear. I then glued this piece to the wheel so I could secure its location while I drilled the hole to lineup/spot my rollpin hole on the gear itself.

Some parts showed up today so I got to work in completing the throttle-body swap, needed to get longer bolts to mate the throttle-body to the tb adapter because the casting was too tall on the tb for the hardware provided - but that was an easy fix.

Proceeded to then add my PCV system ports to the valve covers, those are now done and will be taken into work tomorrow for some sandblasting and eventually painting.

After this I ran out of things to do again…  so I started tearing into what I could do with the time I did have, so I took the tq converter off of the LY6 to check it out.

 

PROBLEM! AKA fun fact, the 6l90E on the Ly6 has 3 bolts for the tq converter to flexplate, the BB has 6:

And they don’t line up at all…

And the big block may have a unique flexplate that is not shared with the Duramax.

 

The 6.6 got the Allison during the GMT900 but there was no big block for GMT900 so the current parts bin method may not work for this. Maybe I need a custom flexplate? Or the other option (purely assuming things here with parts bin rationale) that the 4l80/85E tq converter will work since it is the same bolt style (6 pad 11.5” spacing) and was offered in the big block… they both have the same pilot diameter (1.7”/43.22mm) but all other dimensions are currently unknown to me at this time.

Does anyone know how different the tq converters would be between the hydromatic 4 speed HD and the hydromatic 6 speed HD? Yet there is nothing wrong with my current tq converter (mechanically/condition speaking)

The wildest option is weld tabs onto the tq converter to use the 6 holes but I think this is most prone to error and might cost more in the end.

So this then that sent me down the rabbit hole, until I found this…

http://www.floridatorqueconverters.com/transmissions-chevrolet-6L80E-6L90E.html

looks like there is a 6 bolt 11.5 bolt circle for the 6l90E so then this should bolt up to my current flexplate. The tq converter has the same pilot and hub dimensions but the price says call… so that can’t be cheap and not to mention hurricane.

Per rock auto here are the 6l90E TQ converter dimensions:

Chevrolet Performance  has 2 different big block flexplates. The image on the one looks to be a 3 bolt but different google searches show 6 bolt…

And I do not know if the 8.1 flexplate is internal or externally balanced.

OldDave
OldDave New Reader
9/12/17 10:35 p.m.

your flex plate shows no signs of any weights welded on it  and all the info I can find says the 8.1L is internally balanced.

any be careful if you buy a cam, the 8.1L has a different firing order that the old BBC.

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