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-   -   out with the old... (https://forums.maxperformanceinc.com/forums/showthread.php?t=856636)

Scarebird 02-13-2022 07:32 PM

out with the old...
 
1 Attachment(s)
My 71 Lemans ragtop had a stroked 400 (440) with Edelbrock Port FI and KRE 85cc heads, roller cam; all hooked up to a M22Z and 2.93 8.5" posi. It struggled to get double digit fuel mileage. I know the purpose of these cars is not fuel mileage, but given we may be in Europe with it and $8/gallon fuel is not good.

So the 440 was sold off locally and the transmission assembly to somebody on the board. My Trans Am has a LS3 EROD crate motor in it coupled to a TKO-600; outstanding power with decent mileage and superb drivability - so I looked in that direction.


GM LS motors come in 3 versions:

1997-2004 Gen III: these are 4.8's, 5.3's, and 5.7's They have cable throttle bodies and cathedral ports

2005-2013 Gen IV: 4.8, 5.3, 6.0 were the main sizes and were drive by wire with rectangular ports.

2014 to present Gen V: 5.3 and 6.2 are the main guys, DBW and Direct Injection and here, with 2019 to present having more advanced ECU's.


I initially wanted to by a Gen IV GM 5.3 crate motor, new - but GM does not sell those even with a big demand for them (the used market is drying up). I ran across this on eBay:

https://www.ebay.com/itm/265152154490

A brand new 2019 L84 with most of the stuff I will need. The sale was consumated and the seller was quick to ship the motor.

https://forums.maxperformanceinc.com...1&d=1644795067


Scarebird 02-13-2022 07:58 PM

Of course I will need a transmission to hook up to this little monster. I initially was set on an automatic; either a 6L80E or 8L90E.
GM supposedly makes a version of the former hopped up for aftermarket use.
But it is not available due to the chip shortage (this trans has one inside the case). Same story with the 8L90E. Another issue is these do not fit A bodies that well at all, and the pan sits about 2" below the frame. Also, a common issue with ECU tuners is the Engine/trans interface. :rain:

So, let's see what's going on with the manual side of things. Tremec has come out with their new TKX; I guess a slimmer version of the TKO. I noted online these are somewhat scarce, and 5.3's are not drilled for input shafts. Bugger.

So I shelved the trans issue until the engine showed up Monday. Or so I thought as it appeared late Friday afternoon as I was gearing up to go home.
It was quickly unloaded and cover removed to reveal a pair of counterbores, the outer being the modern pilot bearing size! So much for internet experts.

Friday night was occupied by a search for transmissions, bellhousings, and flywheels. The Gen V (LT) architecture is NOT the same as the earlier series: bellhousing won't interchange as the top bolt is offset for the high pressure fuel pump. Oil pan, motor mounts and other stuff is different too. F

First item is the bell housing - it is the key here. Some searching revealed Lakewood makes a nice little piece:

https://images.holley.com/583x/lk5000k_01.jpg

Holley sells them for $371.95, part #LK5000K Summit was out, as was Jeg's


Excellent, now to secure a TKX. Holley also carries them in 3 flavors:

TCET17805 2.87 FIRST AND 0.68 OD
TCET18083 3.27 first and 0.72 OD
TCET17722 2.87 first with 0.81 OD

https://images.holley.com/583x/tkx_001.jpg

I selected the TCET18083 due to it's deeper 1st (good for traffic and hills)and middling OD which won't be too onerous with the 2.93's out back

In stock at Holley and $2,795 to the back roll up of the shop.

Another dividend of the TKX is I can still run the steam gauges and not have to go GPS or CANBUS driven gauges. I plan to work with Speedhut to make a more stock looking gauge unit than the Dakota setup this summer when things slow down a bit.


gtospieg 02-14-2022 07:14 AM

Very cool...and with your 2.93s and stockish tire height your final drive will be 2.10 to 1. That thing is gonna cruise at LOW RPM and should get great mileage.

JSchmitz 02-14-2022 07:35 AM

That's a pretty good deal. I haven't stayed up on the latest truck engines. Looks like 355 horsepower. That's up quite a bit vs. the previous 5.3. I think they topped out around 320hp.

HWYSTR455 02-14-2022 09:09 AM

Wow, that's a great deal for a long block! Congrats!

.

Scarebird 02-14-2022 12:02 PM

This article cemented it for me:

https://www.motortrend.com/features/...4-868d2dad0e4b

As you see the Direct Injection motor is significantly more powerful and efficient.

https://www.motortrend.com/uploads/s...und%7C1000:625

Since I am deleting the DOD feature, I will need a new cam - I plan to use the LT1 delete cam, about 6 degrees more duration and 0.050 more lift.

Scarebird 02-14-2022 12:05 PM

1 Attachment(s)
This is a shot of the L84 with her fiddly bits exposed.

https://forums.maxperformanceinc.com...1&d=1644854666


JSchmitz 02-14-2022 12:23 PM

I'm going down the same road. Currently have the interior out. I'm working on repainting the dash. Next rewire whole car. Stock 5.3 to get it rolling. Then I'll step it up. The direct injection is cool. I need to read up on that.

Scarebird 02-14-2022 12:47 PM

More than willing to help - this is a lot of research as the DI motors are another breed from the LS' units.

GM would sell a metric ****load if they made 5.3 Gen 4 longblocks for 4-5 grand.

Scarebird 02-17-2022 03:30 PM

TKX arrived today - gave it the once over to verify no visible damage. Info sheet shows it use a Ford manual speedo...

https://cdn.shopify.com/s/files/1/01...g?v=1641419945

This little bugger, part number 7002129, 7002131, speedo gear runs $93 shipped to a US address from Bowler Mechanical. Will need a new cable as the output is on the driver's side unlike the M22Z.

JLMounce 02-17-2022 04:56 PM

I was under the impression that the TKX also had a VSS signal?

Scarebird 02-17-2022 06:53 PM

It does, in fact it may have 2 different types as there are 2 pigtails coming out of that area.

gtospieg 02-17-2022 10:27 PM

One of those pigtails may be for reverse lights.

Scarebird 02-18-2022 12:59 AM

That one is on the driver side - a detent switch with two threaded posts that are too close to each other if it is anything like the TKO 600 I have...

I found this to explain more, page 12:

https://www.tremec.com/anexos/TKX-Se...KX_09.2020.pdf

Scarebird 02-18-2022 06:23 PM

4 Attachment(s)
The LT1 headers came today. These are 2016-2020? Camaro 6.2 liter non-supercharged manifolds. They are formed and welded - very nice pieces. Note also they are Tri-Y style. The manifolds had a width issue: the were 29-1/4" outside to outside. The headers clock in at 25-3/4" - much better and able to drop in.

https://forums.maxperformanceinc.com...1&d=1645222684

https://forums.maxperformanceinc.com...1&d=1645222703

I will still need to mod the clutch bellcrank to clear, or fab a new one - maybe 1964-67 style. The red circle marks where on the block the old pivot bolt was on the 440.


https://forums.maxperformanceinc.com...1&d=1645222713

https://forums.maxperformanceinc.com...1&d=1645222722

gtospieg 02-18-2022 07:18 PM

Those headers don't look like you can dent them to make that stud work. Time for some creative fabrication.

Scarebird 02-27-2022 11:28 PM

2 Attachment(s)
no, it won't work at all without heavy modding. As you can see the passenger side runs head on into the A-arm rear mount.
It would take a sizeable amount of modding to clear.

https://forums.maxperformanceinc.com...1&d=1646017886

The factory L84 (truck) manifolds are worse. The flanges span is about and inch too wide to fit inside the frame rails - so they are out.

https://forums.maxperformanceinc.com...1&d=1646017900

I ordered a set of Hooker manifolds, part # BHS516. Hopefully they clear, another Summit customer noted they cleared his 72 Chevelle.
If not I will need to revisit modifying the headers.

I do not think they can work with the stock clutch Z-bar.

https://www.vividracing.com/wm.php/i...M/BHS516_4.jpg

gtospieg 02-28-2022 10:00 AM

I thought someone offered LS/LT swap headers for A bodies. Are any available or are you wanting to stick with manifolds? Looking forward to seeing more about your swap and how it performs.

Scarebird 02-28-2022 11:00 AM

Engine swap Supply has these, but not in shorty form for "A"s as far as I can tell.

I have not seen a big enough difference in tests online to warrant the trouble of headers.

Note that LS headers will not work - the exhaust and intake ports swapped positions, one of the big differences between LT and LS motors.

Other issues are oil pans, motor mounts, intakes... it goes on and on.

andrewb70 03-09-2022 11:55 AM

I haven't ben here in ages, but this build is exciting! I recently helped a buddy with a LT1 into a BMW, using the Holley Terminator X Max with DI. The engine has a baby cam and it is a monster. It is making as much torque and HP as his previous 408 gen 4 stroker and it idles at 40kPa, which is just mind blowing.

I hope you use the Holley Terminator X Max!

Also, Silver Sport transmissions makes an excellent hydraulic clutch kit for the TKX. I've used their firewall MC mount for years in my GTO and it works great. I would lean in that direction for clutch activation. You won't be disappointed.

I tune Holley EFI for a living and would gladly offer help with wiring and tuning, if you go with the Holley EFI.

Andrew


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