Thread: 2005 GXP Big Turbo Build **Street & Strip**

It's going to be a pita getting the oil pan in from the pics but I'm sure it'll work fine.

Originally Posted by 91parkave

It's going to be a pita getting the oil pan in from the pics but I'm sure it'll work fine.

It surprisingly goes right up with a little finesse. It's crazy how deceiving this transmission looks. I was amazed how it practically fell into place.

I posted some other stuff on ls1tech for you to ponder

Also while you're in there if you want to convert your fuel module to AN lines I got some pics of how I did mine

Originally Posted by Turbocharged400sbc

yeah... not doable



it wont work...
aside from having to section and weld in the ls4 starter boss into the 80e bellhousing...you have a differential housing that would occupy the same space as the engine block skirt. whether enough meat is present to grind it and get it all to fit or whether the block or trans would have to get cut and welded....couldnt tell you

your only option is to hope you can find all the GMR parts you can for the ls4 4t65e and keep a couple spare tranny's in yer trunk lol

I believe what hes saying is you need to shove a bruce/catilyn jenner in the trunk as a spare tranny.......

I cant wait to see how this ls4/4t80/turbo monster comes together!! A lot of good things happening in the wbody world right now! Maybe the platform isn't dead!

I'm sure at some point, someone told James something wasn't doable and he proved them wrong. It's good to see people taking a moment and trying things to ensure others were right/wrong. Afterall... most of us aren't lemmings.

Originally Posted by BillBoost37

I'm sure at some point, someone told James something wasn't doable and he proved them wrong. It's good to see people taking a moment and trying things to ensure others were right/wrong. Afterall... most of us aren't lemmings.

yeah people told me that the SI and SII dont share parts...they do, told me the 80e couldnt work with the 3800 pcm, i found a workaround.
you cant make a twin engine car work....did it...now clean-sheeting it. couldnt delete the bbv on a whipple kit...did that, actually ran cooler, less idle issues.
where there's a will, there's a way. but considering the cost premium of the ls4 cars...sure as **** makes you wonder why GM didnt do it....

when i measured a charred to hell ls4 the distance from the crank centerline to the skirt looked like the engine and trans would both be fighting over the same .5 inches of real estate and it looked like it was right at the thin part of the block skirt, not a meatier area like the main web...

is there room on the blocks bellhousing face to drill and tap the block for the new "***** bolt" location?

Originally Posted by 91parkave

Also while you're in there if you want to convert your fuel module to AN lines I got some pics of how I did mine

Thanks for the help and pointers. I am not sure what I am doing with the fuel system yet. no matter what it will be dynamic, but I might just fabricate a cell in the stock location with an Aeromotive Eliminator pump, or maybe a Holley Dominator.

Originally Posted by 98BrokeMyCarVet

A lot of good things happening in the wbody world right now! Maybe the platform isn't dead!

Not even close!
We are working on a few other tid-bits as well.

Originally Posted by Turbocharged400sbc

sure as **** makes you wonder why GM didnt do it....

when i measured a charred to hell ls4 the distance from the crank centerline to the skirt looked like the engine and trans would both be fighting over the same .5 inches of real estate and it looked like it was right at the thin part of the block skirt, not a meatier area like the main web...

is there room on the blocks bellhousing face to drill and tap the block for the new "***** bolt" location?

As far as modification to fit the motor, the crap bolt on the block needs to be removed. There is no room to drill/ tap to add the bolt hole back. If you loook at this picture of the motor on the stand, you can see the recessed area around that bolt location. I literally used that as a cutting guide to remove the material and it fit like a glove. It's like GM included a dotted line LOL.




The other area that needed modification was where the differential/ output shaft cover bolts to the transmission. Right at that spot I removed roughly an 1/8" of material from about a 3/4" long area of the oil pan rail and one little stub on the block.



The finished product obviously looks a little nicer.

Next on the list is to make a template for the starter pad so I can cut the bellhousing, index the pad and weld it on.
Either way, at this point it is a very promising conversion.

Originally Posted by zipper

This makes me want a 4t80e. I'll be watching this thread for sure. Awesome work!

Thanks!
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Set the driveline square last night and started building the mounts. Pretty busy at the shop, most likely won't be back on the project until Sunday unless I get one good solid late night during the week. Time will tell.

Slingshot Engaged!!!

For some reason I think these pics are making my shorts grow..........

Excellent once I see a started bolted up ill be convinced this is a go!

I have the same welding helmet at work.

Damn that's one hell of a turbo! I'm digging the project and the color!

But more importantly.....what's the deal with iroc you're hiding back there???

Originally Posted by 87IROCZOWNER69

Damn that's one hell of a turbo! I'm digging the project and the color!

But more importantly.....what's the deal with iroc you're hiding back there???

Thanks man.

The iroc is a customers car I am building. Twin turbo setup we put together on a LS3 based 418ci motor. Twin 6266 with billet wheels.

Are those them ebay flipped headers??

Some of the guys on performancetrucks.net use those for builds.

Originally Posted by Fivefingerdeathpunch

Are those them ebay flipped headers??

Some of the guys on performancetrucks.net use those for builds.

Actually they are. We have used them on a few builds. I cut them back tight at the collectors and reduce them down to 2.5"
They work, but for a turbo application, the primaries and collectors are huge right out of the box.

Here is another twin turbo package I put together that had china GT45s using those headers as well...

Yeah, they work just fine for ebay stuff.

just a heads up but dont lock in the axle centerline yet. youll want to set it so that the axles go upward towards the tires slightly so that at wot/hard acceleration you keep em straight. depending on how lowered you are, you may still have to raise the ass end of the motor/trans

Originally Posted by Turbocharged400sbc

just a heads up but dont lock in the axle centerline yet. youll want to set it so that the axles go upward towards the tires slightly so that at wot/hard acceleration you keep em straight. depending on how lowered you are, you may still have to raise the ass end of the motor/trans

We are actually making our mounts modular. The concept is to have 2/3 piece mounts all the way around. This would allow us to run an isolator in-between (read polyurethane) for street cars, or a solid insert for race applications. As you mention, that will also have the added benefit of being able to adjust drivetrain height in relation to axle centerline which I didnt even think about. Awesome point.

I would like to offer this package as a full conversion if I get all the details squared away, so I am trying to think a few steps ahead haha

first time i looked through this thread. awesome. do work, man. make us all want your car.

because all we ever wanted was a high horsepower FWD car that we can't stop breaking, hah.