LS2 + 6T75 Build (Page 1/24)
Dan86GT OCT 21, 10:55 PM
And so it begins...

The car is an 86GT.

Engine is a 6.0L from a Trailblazer SS. I took the truck manifold off and replaced it with a car manifold. The oil pan and the front cover is from an LS4. I don't think I am going to use the water pump from the LS4. I may build a piece that will accomodate a thermostat, heater bypass, and plumbing connections to an electric water pump.

The transmission is a GM 6-speed automatic - the 6T75. Does anyone else know if this has been put in a Fiero before?

Current status:



-Dan
MountainHiBlue87GT OCT 21, 11:27 PM
cool, but avoid electrical water pump

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1987 Fiero GT - 2006 3800 Series III Drive by Wire; Ported & Polished by TrippleEdge; 1.7 Yella Terra Full Roller Rockers; VS Cam; Tuning by Darth; WCF CAI & 1 5/8 Stainless Headers, 3" Exhaust, Power Steering & Much More; MSD Coils & Wires; Porsche (Brembo) Calipers on 13" Viper Rotors; 18X8 TSW Indy Wheels; Paint by Phoenix Auto in California City.

MstangsBware OCT 21, 11:49 PM
The swap with the 6 speed auto has not been done. A friend was working on an adapter plate for this swap a few years back but unsure how far he got on it.....
Dan86GT OCT 21, 11:52 PM
What has been your experience with an electric water pump?

Dan
MstangsBware OCT 21, 11:55 PM

quote
Originally posted by Dan86GT:

What has been your experience with an electric water pump?

Dan



Nothing wrong with using an electric pump....many have used them with no issues...I even thought about iit on mg LS4 swap but just used the stock setup....
CowsPatoot OCT 22, 02:44 AM

quote
Originally posted by MountainHiBlue87GT:

cool, but avoid electrical water pump




I am also curious as to why. I only have experience with one electric one, and it left me wanting to go to electric for all my vehicles.
dobey OCT 22, 08:07 AM
Where in VA are you?

The Archie adapter plate should work fine with the 6t75, if your trans is using the Metric bellhousing and came off a 3.5 or 3.9 V6 car. The real problem is going to be the electronics/programming side of things, with that combo.
fieroguru OCT 22, 08:35 AM
Sounds like a very good project!

If you use the LS4 oil pan, you probably want to block off the oil bypass it has for DoD.

You probabaly want to start with and ecm/tranny controller for the transmission with the ecm from the same family as some of the V8's. Several of the LS4 guys on LS1 Tech have looked into this conversion and haven't gotten past the electronics of transmission control yet. Maybe there is more vendor support now than a year or two ago.
http://ls1tech.com/forums/l...ed-conversion-3.html
http://ls1tech.com/forums/l...ns-conversion-3.html

Since the 6T75 is physically similar in shape/format to a manual transmission (differential output on passenger side is flush with the bellhousing), then you can probably adapt an Archie adapter/starter setup to keep the starter on the engine side. My starter solution for the LS4/F40 (or the LS4 starter location in general) will not work due to the transmission front cover/ being right where the LS4 starter normally goes.



Here is the LS4 starter location... notice the back side of the starter will be well into the area occupied on the 6T75 valve body/front cover housing.



The other starter option would be to place a starter under the oil pan either using the prototype LS4 pan (or a modified LS4 or LS2 GTO pan - but both of these will require modification). Here is the LS4 prototype pan:



GTO oil pan:


LS4 oil pan:
dobey OCT 22, 08:50 AM
Oh. Just saw your mention of the LS4 front cover and oil pan. You probably don't want to do that. The C6 Vette oil pan is a much better choice, and what I'm using on my LS4 that I'm deleting the DoD from. Also, depending on which ECM/program you are using the control the thing, the LS4 front cover has the cam sensor 180 degrees off from where the normal LS sensor is, to clear the offset and tightly packaged water manifold the LS4 has.

Also, if it's from a Trailblazer SS, I guess it's probably the LQ9 (iron block) engine, insead of an LS2 (assuming the SS didn't have a real LS2 swapped in, but it looks like you have the truck intake turned around backwards there). What is the casting number on your heads? Did it come with the LS4 cover/pan already installed?

If you're anywhere reasonably close to Newport News, I hope you make it to the Fall Clasic show at Newport News Park today. You can see a couple of LS376/480 swaps, and chat with some of us about various V8 swap details.
darkhorizon OCT 22, 10:15 AM
My TBSS has a LS2 in it.

Also, the 6T75 trans will probably not run with an aftermarket controller.