LG3 3.8 Turbo Century - Build Pictures

[rwcarnut]

You are an inspiration. I have a 74 apollo that I am installing a hot air 85 motor and wanted to convert it over to intercooled. I have the same intake (off a front driver) installed on the motor, just turned around backwards since it is rear drive. I was unsure as how well this intake and throttle body size would work in a boosted application. It appears that it will work just fine!!!:biggrin: Thanks and keep up the awsome work!

 

[charlief1]

You are an inspiration. I have a 74 apollo that I am installing a hot air 85 motor and wanted to convert it over to intercooled. I have the same intake (off a front driver) installed on the motor, just turned around backwards since it is rear drive. I was unsure as how well this intake and throttle body size would work in a boosted application. It appears that it will work just fine!!!:biggrin: Thanks and keep up the awsome work!

Show some pics and TELL US MORE!!!

 

[rwcarnut]

Show some pics and TELL US MORE!!!

will try and post some pics soon, I should probably start a new post (do want to hijack this one) , was going to introduce my self and project although I an still in the collecting parts phase.:biggrin: thanks for the interest.

 

[87GN_ponykillr]

VERY COOL!!!!! Nice job

 

[Squid4life]

Very impressive, lots of fab work and nice attention to detail.

 

[turbokinetic]

Guys - THANKS for the comments I am very sorry I have not aknowleged them sooner. I never got a forum reply notice e-mail.

The car has been on the road for about 5000 miles now, and the engine has performed beautifully. Have not had to turn a wrench on it!

The roller cam does work the valvetrain harder than the stock cam, and the top end has a little "sewing machine" sound. I beleive it is amplified by the flat top aluminum valve covers, since the valvecovers mount to the ROCKER ARM STUDS and transmit the sountd. It is hard to hear with the hood closed and it is not a disagreeable sound.

Now - as for how it runs? When I first got it running, the wastegate had the stock 9 PSI spring in it. I did my base tuning with that, before connecting the electronic wastegate solenoid. The transmission was barely able to stand that, as long as I didn't let it try to shift to 4th gear at full power.

After connecting the WG control solenoid and turning the boost up to 15 PSI, it will roast the tires effortlessly, make throttle-induced lane-changes, and bury the 85 MPH speedometer in mere seconds. The tires spin wildly in 1st and 2nd gears, and the transmission will slip wildly in 3rd and 4th.

The original transmission was a 440T4. I have built up a 4T65EHD transmission that I am in the process of installing now. Will post the build pictures today.

Here is a video of low-boost acelleration with no WG solenoid and the old transmission. Will do another one with new setup once it is all installed and callibrated.

YouTube - 3 8 accel vid1

I had to be very careful on the 2>3 and 3>4 shifts, so this is not truly at full throttle, nor is it from a standing start. ALso bear in mind the computer screen shown at the very end of the video is the ECM data and the upper right number is road speed.

Thanks!
David

 

[turbokinetic]

I'm working on installing this transmission today, finally have it all together. I may have to have one custom made driveshaft but will see what I can dig up. This is a group of posts from another forum, starting from when I got the transmission core up to now. This is an electronic shift transmission. It has no governor, modulator, TV cable. It came from a 97 Riviera, and was originally controlled by the PCM. My engine has a simpler ECM that will not control the transmission. I am installing a stand-alone (almost) trans controller, from a 93 Chevy diesel pickup. These trucks have a mechanical-injected diesel engine with no engine ECM, and have a trans ECM that uses a "chip" to set the parameters and can be tuned with the same hardware that we use on the chip-tunable engine ECM's.

This may interest some people here who are interested in late-model RWD electronic transmissions for TR's. I would be glad to share what I learn here, if this works out well.

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Have the transmission (it's a guaranteed-good core), CV shafts, all brackets and wiring connectors. Just got the transmission ECU, PROM code, and ECU wiring harness connectors. I was concerned because the part number on the ECU is not what is shown on the documentation for TunerCat. I will have to use TunerCat to adjust the parameters in the ECU since it was originally for a diesel pickup truck and the shift points and gear ratio calibrations are all wrong for a 4T65E. I hooked it up on the bench, just to a power supply, "Check Trans" lamp, and scan tool. ECU is at least capable of booting up, flashing the lamp, and communicating with a scan tool. That means the PROM code (that works with TunerCat) does run on this ECU.

The reason I have chosen this ECU is because it is totally independent of the engine ECM. It will share the throttle position signal since my car already has a TPS. On a carburetor car, you could mount the TPS remotely and have the carb linkage actuate it. Other than knowing throttle position, all the other sensors and outputs for the transmission ECU are internal to the transmission. When I get this done, I hope others can benefit from it as well. There are a load of late-model electronic transmissions out there that could be used in older cars. There are already some very expensive transmission ECU's made by aftermarket companies that are better for performance, but this one cost less than $120 as a reman from a local parts store. I am trying to keep with the spirit of only buying something I can't fabricate, salvage, or get as a stock spare part.

There are some differences in the logic used in the 4L80 and 4T65 transmissions. The shift A/B signals can be adapted by inverting the shift B signal with a relay. The pressure switches are more different. I will have to experiment with those signals to determine what will have to be done there. One option is to build a microcontroller-based box that will translate the switch signals and give the ECU exactly what it expects. but I want to do this without building any custom electronics. That way if someone else wants to use my "recipe" it will be possible without any really advanced electronics knowledge. The pressure switches may be able to be remapped in the PROM code.
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Got the transmission partially dismantled yesterday. Still have to break down the clutch packs to change the piston seals but don't want to take them apart until I have the new parts on-hand.

Got it all cleaned up with the old diesel burning pressure washer. To quote a friend "I don't wash it until it is 'clean,' I wash it until it is TOO HOT TO TOUCH!" The openings are covered up mainly to keep dirt and grit out. A little water will not hurt but if the pressure washer blasts grit and dirt into the transmission it can cause more damage. The dirt can cause scratching and scoring as the parts are dismantled, or cause parts to seize in place and be impossible to dismantle without breakage.

Took off all the external parts:

Then took off the structural side cover to get to the valve body and other internal parts:

After the wiring harness comes off, then the charge pump can be removed. Here is an explanation of how the pump can change its output without bypassing any oil back to the sump. It is very efficient and produces much less heat this way. The shift firmness is controlled by how much pressure this pump is making. As engine load changes, the transmission charge pressure has to change, too.

Valvebody looks is great shape:

I will try to adapt a 440T4 single-wide-chain to this unit if I can. Have read that the dual chain is quieter but there have been breakages.

Don't like the looks of that black oil - could indicate internal carnage...

Since this came from supercharged application it has the factory HD final drive. This will be shipped off to be converted to limited slip...

(continued)

 

[turbokinetic]

(continued)
Here is a sign of damage. The clutch plates in the second clutch are burned. This happened for one reason only - the clutch slipped for too long and the clutch plates overheated. Could be due to low trans oil level, excessive engine power, bad piston seals, or ECU calibration error. The overall color of the friction material does not mean the clutch is bad. The bands of charred material do mean there is damage, as well as the heat damage to the steel plates. This clutch would have still worked for a long time as it is in a normal application, but I want to start fresh since it is already apart...

All parts cleaned up and put in a box to keep clean. The plastic tray with compartments holds the hardware. Re-assembling the transmission, the hardware will go back in in reverse order from how it was put in the tray. Each compartment should have ALL its contents back in the transmission before anything is removed from the next compartment. Saves making any assembly errors. If I had to take apart the valvebody I would put the contents of each bore in a separate compartment, along with a piece of paper that might have notes about the valve lineup.

My work area. Not the most ideal but for occasional trans repairs it is not bad!

Hope to have all the parts this week, and may get the transmission back together. Probably will not have time to get the swap done for a month or so.

Got the trans ECU and did some preliminary testing. There was some confusion as to whether this was the correct ECU to use with the calibration editor program. Apparently it is. It will flash codes and communicate to a scan tool.

Later!
David
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Just got most of the transmission together! I am missing out on one mod that may cause me to have to rework it eventually, but time is running out for the old 440T4, it is getting bad in 4th now...

This is what I have going so far:

Limited slip diff - (should be here tomorrow or Monday - Pictures will be posted!)
Hardened input and output shafts.
Wide-chain. Pictures follow.
TCC valve modifications. (TCC should hold some boost in 4th on highway)
Accumulator shims. (not sure if this is necessary; but it was recommended so I did it)
"K" factor 155 (258 MM) torque converter (a little higher stall speed - stock was K 133)
Will be doing a custom ECU setup.

Decided on 37/33 chain with 3.29 final drive. This is equivalent to 2.93 gears. Car has 2.97 now, and it already will wheelspin in 1st and 2nd so there was no need to gear it down any further. Especially considering the boost is currently at minimum and the engine has more torque potential. This will keep the fuel mileage up and make cruising quieter.

The mod I'm missing is mechanical diode sprags. I still have standard sprags. GM used the MD's in newer cars and it will retrofit back.

GM went to a dual chain system when they changed from 4T60 to 4T65E. It was supposed to be quieter, but I've been warned it's a weak link in the system. A broken and wrapped chain can be catastrophic for the transmission.

The 440T4 has a single chain, that is wider and stronger. The drive sprocket is almost the same, save for a few holes to mount the input speed sensor reluctor. The driven sprocket for the 4T65E has a counterbore to accept the larger 4th clutch hub of the 4T65E.

Tore down a 440T4 core to get a set of 37/33 sprockets and took them along with the originals to a local industrial machine shop. They copied the counterbore and thrust washer tab holes onto the single chain sprocket and drilled the other sprocket for the reluctor. The 4T65E has thinner thrust washers on the drive sprocket to account for the thickness of the reluctor.

Can't wait to get this thing in the car and see how much better it works than what I have now!

One reason I want this thing bulletproof is because of my road trips. Having the car shipped home with a broken transmission would cost more than the transmission mods, on top of the frustration and embarrassment!
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Just got the limited-slip final drive! This is the last internal part of the transmission, leaving the torque converter as the only part I'm lacking.

This improves off-the-line acceleration by making both wheels pull at the same speed. It contains a set of brass clutches that are pressed together by springs. Then, as the transmission applies torque to the carrier, the thrust load on the spider gears further loads the clutches. Under hard acceleration, both front wheels are effectively coupled together. Under light loads both wheels can roll at different speeds for cornering with only a slight drag.

Only works when both wheels have some traction; not when one wheel is in mud or off the ground, this is not a locking diff. It is a custom built unit fashioned after GM's tried and true RWD limited slip units.

If you want more information, PM me for the info to contact the machinist who built it.

Can't wait to get this transmission in the car, but it will probably be next month after I get back from work.
Thanks,
David
(continued)

 

[turbokinetic]

(continued)

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And today I am trying to get it installed in the car. Next comes the ECU tuning!
Thanks,
David

Sorry for the multipart message - the forum gives some BS error when I try to post it all as one page.

 

[DaveLC2]

Wow that looks like a really intense project! Great work and great write up

 

[turbokinetic]

It's one of those tinker here and there projects. I do like to drive it, but have other cars for when I have to leave it down for a while.

I like to read about others' projects too. I am learning as I go on lots of this so maybe someone else can also learn something from it.

Just got the RT side CV shaft done, and now the left side one is proving a problem. I beleive the original shaft can be used, however the housing of the inner joint is stuck in the old transmission. I don't know if the splines are half-stripped (and in a bind) or there is a burr on the snap ring groove. I've pried and pried and tried and tried and it will NOT come out. I've even damaged the transmission slightly by prying on the cover.

On my first road trip in this car, that CV joint worked out of the transmission and caused a leak. It pushed back in and locked in easily so I don't think the splines were damaged at that time.

May have to ride out to the place where I store junk, and rummage up another inner joint housing.

I will be posting about the ECU calibration as soon as I get going on that. Hope to have the car on its wheels tonight. The ECU I am using possibly has the potential to control ANY 4 speed GM transmission in a stand-alone setup. (was originally for 4L80E) It was a reman unit for a 93 Chevy truck that cost about $100. The programming stuff could be bought for as little as $300 if you get the bare minimum. (I already have the programming stuff though, from other projects.)

Thanks,
David

 

[charlief1]

Pull the shaft straight out from the tranny , push in hard and then hit it with a hammer several times on the end. It sounds like your lock ring is stuck.

 

[turbokinetic]

Pull the shaft straight out from the tranny , push in hard and then hit it with a hammer several times on the end. It sounds like your lock ring is stuck.

Thanks! I just got it out before I read that. Ended up cutting 2 wood wedges and driving them between the trans and CV joint, 180° apart at top and bottom.

Then I hit the joint housing with a heavy brass hammer, left and right. After 2 or 3 tries with increasing force, it popped out.

The CV shaft was new when I commissioned the car, just a few thousand miles ago, and it was a cheap chinese knockoff of a Saginaw shaft. The machining in the snap ring groove is poor and there are burrs I can feel.

I will put a small wire brush in there before I put this in my new trans.

Thanks,
David

 

[charlief1]

Use a triangular file and go inside to clean it up before you use the brush. And use some carb cleaner inside to get rid of any oil. Can you tell I've had to do a few of those? LOL

 

[turbokinetic]

...Can you tell I've had to do a few of those? LOL

Yep it shows!!!

After all that, that joint was a non-standard unit (chinese counterfeit) and I could not use it as part of my hybrid shaft. The splines were wrong anyway.

Here is what I ended up using to build up a set of CV shafts to install a 4T65EHD transmission (from a 97 Riviera) into a 1984 Century with JA2 heavy-duty suspension...

RIGHT-side assembly is made up of:
-Inner joint, complete - 97 Riviera (4T65EHD RT spline is different than 440T4 or 125C spline)
-Shaft - Riviera LEFT shaft (shorter than Century RT shaft because HD trans is longer than 440T4)
-Outer Joint:
--INNER RACE from Riviera (larger internal spline to fit HD shaft)
--OUTER HOUSING from 84 Century - to fit JA2 A-Body wheel hub spline.
--Cage and balls same for either style joint but used from Riviera joint.

LEFT side assembly is made up of:
-Outer joint, complete - 84 Century JA2.
-Shaft - 86 Century with 440T4 (4 speed)
-Inner joint, complete - 84 Century 125C 3 speed (125C LT spline and 4T65EHD LT spline are same)

Sounds crazy but as assembled, both shafts have an acceptable amount of plunge depth and lock into the trans and hubs properly!

Isn't there an AMAZING amount of grease in a CV joint. I have thrown away POUNDS of old grease and paper towels working on these things. When I repacked them, it took only one tube of Lucas Xtra Longterm grease. I guess grease multiplies when sealed up in a CV joint?

Tomorrow I may post the install pictures, if I have time. Car is about ready to be lowered back to ground, but there are details like torque converter bolts, trans oilcooler lines, exhaust and charge pipes...

Later,
David

 

[GNVAIR]

That is probably one of the most amazing and detailed swap posts I have ever seen. Love the car. Keep up the great work!

 

[turbokinetic]

That is probably one of the most amazing and detailed swap posts I have ever seen. Love the car. Keep up the great work!

Thanks! It is running great. The only drivability problem is a warm-restart problem. I think the fuel tables in the ECM need to be tweaked a little, that's all.

Here is the install of the trans:

Success!!!! The transmission is in, and it works EXTREMELY well!

Got all the external pieces installed. The wiring is close to the exhaust, so I wrapped it in lagging. The exhaust pipework is lagged, and the harness is also lagged so that between the 2 the wires should hold up OK.

There were very few things that needed changing to make this work, mechanically. First thing was the driveplate. This thing has a massive 258mm torque converter. The bolt holes were off by half a hole, so I slotted the driveplate to work with this converter. The driveplate is balanced for the LG3 3.8, and they never made an externally balanced 3.8 with this type converter.

This is another HD converter, with the unmodified driveplate sitting on top:

After slotting:

The case "tower" where the electrical plug comes out, was in the way of my slotted-out shift cable bracket. This was how I adjusted the 3-speed column shift mechanism to work with the 4 speed trans. Becuse I could no longer move the bracket back, I had to mod the bracket at the other end of the cable, under the dash. Now it is an adjustabracket!

(continued)

 

[turbokinetic]

(continued)
Now the trans is sitting on my homemade trans jack (old driveplate bolted to the jack!) and going up to the engine:

It bolted right up with no problems and the converter bolts lined up perfect!

The original 440T4 mounting brackets for the left side of the powertrain fit the 4T65EHD with no problems, because I started with an early model core. If the trans is newer than 1999 (IIRC) it will not have the correct bolt pattern on the back. Thankfully mine bolted right up.

The tail shaft support piece braces the final drive to the engine block. The 440T4 was several inches shorter than the 4T65EHD. The 4T65EHD's bracket fits an L67 engine with a different mounting setup. I ended up cutting the 440T4 bracket and welding it back together, then adding some extra support. It looks pretty good and will hold!

I used the 440T4's speedometer cable heat sheild for a trans output speed sensor sheild!

The CV shafts required some tinkering to get right, and the right outer joint is clicking because I ended up with a "rebuilt" oversize housing and normal size race. You can see how much larger the HD joints are:

Finally, the mounts, cooler lines, and CV shafts are in place! Looks like it was meant to be in there!

So what is the difference in this unit and the 440T4 since they look so much alike?

Cast aluminum "Structural Side Cover" instead of stamped pan.
Stronger charge pump.
Larger HD 258mm (10 1/8") torque converter (440T4 had much smaller converter)
HD Final drive gears much larger.
Shifting is additive, no clutches release during upshift sequence. More precise feel.
Cooler lines larger (3/8 instead of 5/16).
Full electronic shift control. No modulator, TV cable, or governor.
No speedometer cable connection.
Has transmission ECU - shift points and shift feel fully adjustable (through programming) without opening transmission.

It shifts awesome. Feels more like the early European cars than a GM transmission. The shifting out is very quick and precise, but is not harsh. Going from Park to Reverse is almost imperceptible!

Will post more about the electronics when I have time.

Thanks!
David

Ps: The old 440T4.... It survived, but I think there are some badly burned clutches. And look at the burn marks on the converter in the TCC clutch area!

 

[vicious6]

Unreal Fabbing Man! Great job, keep us informed!

 

[turbokinetic]

'Preciate the compliment! Car has been running exceptionally well! I have seen as high as 18 PSI boost with insane acceleration - it is a blast to drive!

I am anxious to put this on the dyno, and tried to schedule it before going off to work this month. Hopefully when I get home after this hitch (work trip) I can get it tested out.

It will break the front tires loose (both front tires with the limited-slip) if floored at 60 MPH. Car has more power than I expected!

Thanks and will post dyno results when I get them!

David