The cooling system turned out nice. An electric water pump sends coolant to the block via 2 -12 lines that go into the two ports on the custom water manifold we made. The coolant comes out of the engine and if the thermostat is closed it goes out the heater bypass and to the heater core through one of the factory heater lines. It then comes out of the heater core and back into the inlet of the pump to repeat the cycle. This allowed us to drop the other heater line that runs to the back of the car. This also provides quick heat in the winter... When the thermostat opens it runs to the radiator.
In an attempt to make bleeding the system easier, we put a ball valve bleeder on top of the water manifold (the highest point of the system). I thought bleeding the system would be easy with the pump - just turn on the electric pump, crack the bleeder, and wait for the air to work its way out. Yeah right. Bleeding was still a time consuming task that involved engineers standing around deriving fluid dynamic theory. In the end the Laws of Physics prevailed and the air was out of the system (I think...)
Here are some pics...
The water manifold
The pump fit nicely under the front tray.
The inlet side of the pump. You can see the smaller heater line coming in from the heater core.
The outlet side of the pump. Two lines going to the engine.
So.... Can you successfully control a 6T75 out of the stock vehicle??????
Its not a great burnout.... but it was only about half throttle....
We drove the car around to dial in the transmission calibration. It shifts very nice.... The car is actually very quiet. Maybe too much muffler... Need to order a cutout...
I used a "TCI" trans controler ( by PCM ) Their were issue's. Joey, in tech support walked me through it. He sent me code to get it to work. I put my ecm and tcm behind the drivers seat to keep them IN the car. they are on a board untill I can mount them. With the seat back so I can drive it, you can't see them. The data cords are in the car. I work on it from the pass side. It was easy to intergrate the tcm, ecm, wide band, and CC.
Oh my....... is that a tape deck with a Cro2 button and a built in EQ ??!! I got some mix tapes I'll sell you. Even got some Quiet Riot tapes somewhere. Kidding aside..... Nice swap. Now, get the flux capacitor wired up and get that thing to the dragstrip!!
Oh my....... is that a tape deck with a Cro2 button and a built in EQ ??!! I got some mix tapes I'll sell you. Even got some Quiet Riot tapes somewhere. Kidding aside..... Nice swap. Now, get the flux capacitor wired up and get that thing to the dragstrip!!
The Bald Guy
lol, that's funny! badass high tech swap, still rock'n a tape deck...
This is full trim including all interior, hood, decklid, etc.. All fluids including trans fluid, oil, coolant, and half a tank of fuel.
That's impressively light... My Northstar/Getrag '87 GT was 2895 at MIR. The Northstar shortblock is lighter than the LS4 shortblock, but I had spare tire and jumper cables up front; otherwise full weight with 1/2 tank of fuel.
There is a box with the shift cable you can mount anywhere in the car. The trunk seemed to work the best for this project.
Then the cable just hooks up to the transmission like normal.
I really like that shifter! I just made a wireless paddle shifter for my Diablo kit kit yesterday out of a $20.00 ebay remote door lock/unlock kit for my transmission controller that controls my 4t65ehd: But I like yours better!
You skipped over how you handled the axles. Could you please explain what was involved in getting the transmission to wheels connections in place ??
If I understand Dan's posts correctly on page 2, it sounds like the axles were probably custom made. Given the size of the 6t transmissions though, it looks as if the manual Fiero axles might also be usable, possibly having to swap the inner tripots for something that fits the 6t splines if they aren't the same as the Fiero splines.
I second that, can we expect it to be available soon? Any estimates on price?
I assume you are talking about the push button shifter. It retails at $1199, but I imagine you will be able to find it cheaper once our dealers get stocked up. We are just beginning to ship it. The one in the Fiero is an actual production unit - not a prototype. It will probably take a few weeks for the backlog to clear and then it should be pretty easy to get one. You can also add a paddle shifter for a few hundred more. I am going to put one in this car and will take a pic when I do. I am just waiting for the column adapter to come in...
quote
Originally posted by fierome:
How are you implementing torque control on this setup (GM DBW, Spark)?
Can you setup the 6T75 without the shift box - regular cable and lever?
You absolutely can have the 6T75 work with a regular cable and lever. Just get one for a modern GM 6-speed - they are PRNDM. It will work fine.
The push button shifter will work on any transmission that uses a shift cable - even older nonelectronic transmissions. It just replaces the shift cable.
For torque control we are using the E40's torque reduction. We are basically just translating between the 6T75 and the E40. You have many options to accomplish this and we are going to experiment with most of them on this build. I will document what works, what doesn't, pro's, con's, etc. Other ways of cutting the torque include timing retard - such as a nitrous module.
You skipped over how you handled the axles. Could you please explain what was involved in getting the transmission to wheels connections in place ??
I bought a set of used axles for the 6T75 from a 2008 GMC Acadia. This includes the intermediate shaft. I sent them and the stock fiero axles to the Driveshaft Shop. They made a custom set that would be 6T75 on the trans side but still have the Fiero splines for the stock hub. For reference, if you look at the drawing in the link below, I used the following lengths.
Length from intermediate shaft to hub: 17.25" (length "A" in the online drawing) Length from trans to hub: 13.5" (length "B" in the online drawing)
Obviously these numbers may change if your transmission is mounted differently, but they worked for me. I will take a picture next time I am at the car.
Oh my....... is that a tape deck with a Cro2 button and a built in EQ ??!! I got some mix tapes I'll sell you. Even got some Quiet Riot tapes somewhere. Kidding aside..... Nice swap. Now, get the flux capacitor wired up and get that thing to the dragstrip!!
The Bald Guy
You know you are jealous of the true fidelity the CrO2 button provides. You failed to comment on the "LOUD" button.... which I am going to wire to the exhaust cutout.....
What have you done to the transmission to beef it up to handle the LS engine?
Thanks
Archie
Excellent question. The transmission that has been used throughout this build so far has an unknown past. We were basically just using it for mockup, design, and system validation. As soon as we were comfortable that everything on the vehicle, engine, and transmission was functioning properly (put a few miles on it, calibrated the transmission, made sure all the cooling worked, etc) we tore the whole thing apart.
We are now going to begin phase 2 of the project which involves durability testing of the transmission. We will have, on Monday or Tuesday, a brand new (technically factory GM reman) 6T75. We went down to the local GM dealership and ordered a 6T75 for a 2010 GMC Acadia. We will have a known good, 0 mile, stock transmission. Starting with a stock transmission, we are going to lay the power to it and see what breaks. When something does break, I will post it here along with the solution to make that part stronger. We have a chassis dyno so I will also be able to post exactly how much power we are working with. This is a slightly used LS2. If we are having a hard time breaking the trans, we will add some upgrades to the motor.
Will the 3.4DOHC bolt up or would an adapter plate be necessary?
There are versions of the 6t transmission available with the metric bell pattern, which would bolt directly to the 3.4 DOHC. Look at ones from cars with the 3.5 and 3.9 V6 engines.
There are versions of the 6t transmission available with the metric bell pattern, which would bolt directly to the 3.4 DOHC. Look at ones from cars with the 3.5 and 3.9 V6 engines.
That would be the 6T70. Not as "beefed up" as the 6T75 but adequate for that 3.4 for sure.
Nice pictures Dan. Keep them up!
I would love to see more transmission/adapter plate (with starter provision) images and information.
Originally posted by GXP25: That would be the 6T70. Not as "beefed up" as the 6T75 but adequate for that 3.4 for sure.
I wouldn't really say the 6t75 is "beefed up" any more. It's only rated at 20 lb-ft more torque handling. The listed HP rating is the same for both transmissions. Not sure what the exact differences are, other than the 75 being an obvious evolution of the 70, but most all of the internals are the exact same parts between the two.
Excellent build! Looking forward to the trans durability testing.
Do you have any more pics of the finished water manifold?
Here are some more pics of the water manifold and the adapter plate.
The starter is from an LS4. We could have designed the motor plate to have the starter mount directly to it, but we wanted to be able to adjust the starter lash with the ring gear easily.
The 6T70 lacks the following when compared to the 6T75:
A wider transfer gear, a heavier ribbed case, a heavier duty differential carrier, a shot-peened output carrier, and a 5 pinion carrier.
Remember that these transmissions were deployed for use with 4,900 lbs vehicles.
According to the factory GM specs, the 6T70 is rated for a maximum engine torque 280 lb-ft and the 6T75 is good to 295 lb-ft. The 6T70 has a maximum gearbox torque of 332 lb-ft in first gear and 380 lb-ft in all other gears. The 6T75 has a max gearbox torque of 380 lb-ft in all gears. Both transmissions were validated to a max gross vehicle weight of 6400 lbs.
We just so happen to have a 6T70 and a 6T75 in the shop....
The 6T70 is on the left. This is the differential transfer driven gear (bottom gear) and the differential drive pinion gear (top gear). The size increase is quite substantial.
Again, the 6T70 is on the left. The differential ring gear is larger on the 6T75 and overall the diff is wider.
This is the 6T70 diff transfer drive gear. Note the "bare" or "non-gear" portion to get a sense of the width of the gear.
This is the 6T75 diff transfer drive gear. Now look at the "bare" section.
We tried to look for differences in the case. The only major thing we noticed was the support structure around the diff housing. The above pic is the 6T70.
The 6T75.
Tomorrow we will tear into the input carrier assembly so we can show the 4 pinion vs 5 pinion and any other differences.
After looking at both of these transmissions I think that the 6T75 is designed to handle much more than a mere 15 lb-ft over the 6T70. I actually think that both transmissions are very conservatively rated by GM, and I am not sure we are going to break anything....
do the "upgrade" parts interchange between the two?
As far as the diff and transfer gears I would have to say no - or at least - not easily. Externally the cases appear to be the same, but internally the 6T75 case is designed to hold the wider diff.
It would be nice if you could at least swap the input carrier from the 4-pinion to the 5-pinion. We should have that answer tomorrow (with pics!)
Originally posted by Dan86GT: As far as the diff and transfer gears I would have to say no - or at least - not easily. Externally the cases appear to be the same, but internally the 6T75 case is designed to hold the wider diff.
It would be nice if you could at least swap the input carrier from the 4-pinion to the 5-pinion. We should have that answer tomorrow (with pics!)
It would be interesting if the 6t70 bell face could be swapped onto the 6t75 main case. Then at least it would be easy to get the metric bell pattern onto a 6t75 to avoid having to do an adapter plate, or a special adapter plate, for most of the Fiero engine swaps, while being able to use the case that's designed to handle the larger diff. Or if possible, perhaps the 6t70 case could be modified internally to handle the larger diff?
It would be interesting if the 6t70 bell face could be swapped onto the 6t75 main case. Then at least it would be easy to get the metric bell pattern onto a 6t75 to avoid having to do an adapter plate, or a special adapter plate, for most of the Fiero engine swaps, while being able to use the case that's designed to handle the larger diff. Or if possible, perhaps the 6t70 case could be modified internally to handle the larger diff?
The only good thing about the 6T70 in this case would be the bolt pattern. However, if most people are doing LS4 swaps, why even bother since a modification would have to be made to accommodate the starter anyway.
This adapter plate appears to provide space for the starter nose when pushed against the block for the LS4 due to its thickness. This would be needed as it is currently not in the OEM starter location; the LS4 block has a gap/"cave" in place for its starter.
Originally posted by GXP25: The only good thing about the 6T70 in this case would be the bolt pattern. However, if most people are doing LS4 swaps, why even bother since a modification would have to be made to accommodate the starter anyway.
This adapter plate appears to provide space for the starter nose when pushed against the block for the LS4 due to its thickness. This would be needed as it is currently not in the OEM starter location; the LS4 block has a gap/"cave" in place for its starter.
Most people aren't doing LS4 swaps. Archie's V8 kits keep the starter on the engine side. The adapter plates are made to fit to the Metric bell pattern on the trans side, and the RWD pattern on the engine side. I'm sure some people wouldn't mind having a 6 speed automatic as an option. And of course, then there's all the other engines that people swap in that already have a Metric (or BOP) bell pattern. I'm sure mounting one up behind a Northstar, with paddle shifters, would make for quite a fun ride too.
I don't have pictures of more transmission internals right now... temptations of doing a big smoky burnout won... so the transmission is back together.
We are going to disassemble another transmission so I will get more comparison pictures in a little while.
For the new transmission, as I previously posted, it is a GM factory reman. We went to the dealer and said we needed a transmission for a 2010 Acadia 2WD.
Here is a picture of the broadcast code of the transmission for reference.
Then we modified it for the starter pocket. This is easy to do. If anyone is going to do this I can post some dimensions or maybe a template so you can duplicate.
First, let me apologize to everyone that has sent me a PM over the last several months... SORRY!!!
I thought my preferences were setup to send me an email when I got a PM but they weren't....sorry... rookie mistake...
To answer the majority of the questions, we obviously have controlling the transmission under control. We are currently refining the software so that it is user friendly. I don't think that is too far away. When we have the software cleaned up I will post some tuning examples.
