1985 C10 long bed L96 6l90e swap

[PhilistineAu]

Well, I've decided to take the plunge!

I've had my C10 for about 6 years now. Purchased it while working in Wyoming from a friend for $1,500. Brought it back to Houston (it survived the hurricane!) and resprayed it "sonic blue" in my garage (neighbors were not the biggest fans). Bought some new chrome and lights from LMC, worked elbow grease and polish on the bumpers and installed new rims. Since the engine runs a bit rough and the 700R4 will no longer shift into second, I thought it might be time for an upgrade.

About 2 weeks ago I purchased a 6l truck engine with the 6l90e transmission. I'm feeling a little out of my depth but there is so much knowledge on the forums, I am hoping people will be able to steer me in the right direction.

I've been collecting copious notes from all the forums. So far this is the plan:
- radiator from a silverado or purchase new aluminum with electric fans
- have the transmission and motor mounts from Tejas Steelworks. Finished painting them black this evening
- purchased a Quantum fuel 340 lph fuel pump, 87 fuel tank with sump, 58 psi regulator and 87 sender unit. Not sure yet about hard line or just run full braided line. Engine is a returnless sytem (so return from the regulator back to the tank). Also purchased the 87 tank switch but will probably run a single tank at first
- need to sort out transmission cooler. Thinking of running and aftermarket cooler up front. I think my sump has an engine oil cooler connection on it as well...
- going to try to use the stock 2015 silverado harness and as many of the 2015 accessories as possible (alternator, AC compressor and fuel pump)
- engine exhaust doesn't have O2 sensors. Supposedly cast iron manifolds may not fit, so may need to get aftermarket headers with O2 bungs and then work out what sensors I need for the L96 harness.
- driveshaft will likely need to be replaced. Do not have a yoke on the 6l90e.
- transmission... not sure if my column shift cable will work or what I need to do here. Pretty sure I will have this sorted before I start the engine so it doesn't shoot forward and drive itself through the garage.
- not sure what some of the piping/connections are on the engine, but think I may have some EGR and EVAP connections that I need to understand...
- wiring. A little nervous about this. Need some relays for the fans. Need to work out how to get power to the fuel pump. Need to understand how to hook up gauges. May need to learn how to install a fuse box.

It's a work in progress.

Phil

[PhilistineAu]

Update: After a few days of forum searching and some real help from Chocolate Apocolypse over at LS1Tech, I have answers to what all this stuff is.


Pic 1: Front passenger side. Steam vents. Connect to the steam vent on the other head and run to the steam port at top of radiator. Used to vent any air bubbles in the cooling system. Older heads had two vents at the back, but because the engines are installed at an angle, the theory is the front vents are sufficient. Some install these vents into the water pump, but I'm going to go to the radiator if I can https://ls1tech.com/forums/conversio...hevelle-4.html Also here for possible kit: https://ls1tech.com/forums/conversio...ent-kit-3.html Some good pictures here: http://www.chevelles.com/forums/141-...team-vent.html Engine coolant bypass https://www.gmpartsgiant.com/parts/g...-12605716.html More info here including part number for previous link: http://www.pro-touring.com/threads/8...-cooling/page2
Pic 2 and Pic 3: These are oil cooler lines from the sump. Nobody corrected me so I'm just going to assume that is the case. Not sure if I am going to use the hard lines yet, but will be using an engine oil cooler. I shouldn't be surprised these are here, considering the engine is from a 3500 HD. If I do go turbo in the future, keeping the oil cool is a good idea.
Pic 4: Transmission cooler lines (run from transmission to front along passenger side). Again, going to run an aftermarket transmission cooler to help extend trans life. Unlikely to be ever hauling heavy loads, but some added insurance if that ever happens.
Pic 5: Front passenger side. PCV. Should be connected into the intake manifold. Thread here: http://67-72chevytrucks.com/vboard/s...d.php?t=420038. Hose from the rear driver's valve cover to top of intake and front passenger's side that goes to intake bellows. Catch can info / PCV info here: https://ls1tech.com/forums/generatio...outing-ok.html Also, see here at step 11 for clearer picture on how it hooks up to intake: https://www.lingenfelter.com/PDFdown...ual%20v1.2.pdf Mighty mouse catch can might be the best option: https://ls1tech.com/forums/forced-in...n-results.html https://www.mightymousesolutions.com...-ls-truck-mild Available cheaper here: http://www.ws6project.com/user_stor/...k0isrfufp1d9c6

[PhilistineAu]

Pic 6: EVAP connector. See image 32 to 34: https://www.lingenfelter.com/PDFdown...ual%20v1.2.pdf EVAP solenoid should normally be closed, so if deleted in ECM, should be able to leave the hose. May want to just blank it off. More information here also: https://ls1tech.com/forums/conversio...ork-right.html One option to vent the gas tank: https://www.summitracing.com/parts/tnk-vvr/overview/
Pic 7: O2 sensor connection. Confirmed by Chocolate Apocalypse. List available here: http://www.rockauto.com/en/catalog/c...2)+sensor,5132 Likely go with Bosch 15282 as it is flex fuel capable. 15283 may not be? but does have a longer connector, which might be better for headers (need to check length of harness once headers are installed).
Pic 8: Not sure what this is. Might be a ground connection point? I think it might be an exhaust hanger to the right. Doesn't appear to be necessary for install.
Pic 9: Transmission breather connection confirmed by Chocolate Apocalypse: "Trans vent/overfill line. I just have mine hanging down so if anything does drip out it just ends up on the ground."

Thanks for anyone who can help out!

[PhilistineAu]

Link to wiring diagram from LS1Tech forum "Pinouts and wiring diagrams". Thanks to 12SEC_SS for the file!

https://ls1tech.com/forums/conversio...iagrams-8.html

I would post it here, but the pdf exceeds the measly ~250kb limit for pdfs on this forum.

[jrdv]

Looking forward to you completing this swap. I need some inspiration!

Hope some of the more LS knowledgeable folks will chime in and help you out with your questions.

It should be a good setup for a reliable truck!

John

[PhilistineAu]

Motor mounts are painted up and the headers arrived. Sadly the headers arrived in a pretty beaten up box with a dent in the collector.

Almost have enough space in my garage cleared to get to the engine hoist.

Next step is to start going through and learning about what I do and don't need to yank out of the C10 engine bay. Plan is to try to be as meticulous as possible with labels.

[vannatta20]

I can help with a harness for the swap. Your factory harness uses the new e92 computer. You can use a factory gen IV harness easier and use the e38 computer.

[mcmlxix]

Originally Posted by PhilistineAu

Motor mounts are painted up and the headers arrived. Sadly the headers arrived in a pretty beaten up box with a dent in the collector.

What motor mounts do you have? I have a 78 2wd Blazer I'm thinking about doing this to...

Originally Posted by vannatta20

I can help with a harness for the swap. Your factory harness uses the new e92 computer. You can use a factory gen IV harness easier and use the e38 computer.

Are you still in Las Vegas? I thought I read in a post you were somewhere else...

[vannatta20]

.
Are you still in Las Vegas? I thought I read in a post you were somewhere else...[/QUOTE]

I am in Vegas. I flew back to see my family for thanksgiving and got my dads swap up and running. Feel free to stop by my work at Motech. We do gen IV and Gen V engine swaps in jeep wranglers. We are on Cheyanne and Lamb.

lswrangler.com has the address

[mcmlxix]

Originally Posted by vannatta20

.

I am in Vegas. I flew back to see my family for thanksgiving and got my dads swap up and running. Feel free to stop by my work at Motech. We do gen IV and Gen V engine swaps in jeep wranglers. We are on Cheyanne and Lamb.

lswrangler.com has the address

I had Robbie do the base tune on my 72 Blazer swap when he was still on Buffalo. I visisted the new shop a couple months ago when I thought I was getting it back from the body guy... I may have talked to you...

[PhilistineAu]

Spent Saturday taking the front clip off and starting to go through and label everything... not that I think I will need half the stuff ever again.

I have no idea what a lot of the emissions stuff is actually doing...

Next steps are to dig around and find out what other connections I need to remove (throttle linkage, fuel line, ground strap to block if there is one, transmission linkage, starter motor electrical connections, exhaust... anything I've missed?). Then it's a matter of hooking up the engine hoist and lifting both of them out.

I'm not the fastest, so maybe another day before the engine and transmission are out. We'll see if the weather plays nice this weekend.


PS Thanks for the offer Vannatta20. It looks like I actually have the e78 computer. The engine is a Gen IV L96 from a 2015 3500HD Silverado. Very similar to the LY6, just with flex fuel capability.

[PhilistineAu]

Removed the old 350 and 700R4 a few weekends ago and finally got the L96 6l90 into the C10 engine bay.

It was much easier to take the front clip off. The engine head bolts worked fine for attaching the leveler. Using the Tejas mounts worked well - no major issues.

We did need to trim the top of the 6l90, which wasn't a huge issue. Instead of using a grinding wheel I just used a hacksaw and went slowly.

I still need to drill the holes into the chassis rails to bolt up the transmission cross-member. I also used the shorter energy transmission mount to get a little more space.

I've attached the connections to the sender unit. In hindsight I might have gone with a sender unit that had the vertical flange instead of the flare. The russel fitting won't fit the flare, but need that vertical flange instead (same as on the fuel rail in this case). I cut off the flares and attached the compression fittings, though they were difficult to get on.

Next steps:
- wire up the fuel pump (the plugs are not the same)
- order x ft of 10 gauge wire in red for the hot side of the fuel pump
- drop sender and fuel pump into the tank
- work out what I am going to do with the vent line and if the line on the back of the tank is also a vent line
- install the tank with the new chassis mounts
- bolt the corvette regulator to the frame
- create the 6AN fuel lines and attach them to the sending unit and the regulator