The G-Body Swap Thread
The Hooker crossmember will not work with a TH350 in any configuration; the mount location on the TH350 is more than 5" further forward than that of the mount location on a TH400 or 2004R, which are the same as a T56 (within 3/16"). What year/model is your car? The 78-up A-body/ Malbu cars have proven to have tighter clearances at the firewall than the G-body designated cars for some unexplained reason.
NO!!!!! why why why!!! i honestly diddnt think they were that different but i only had a 700r4 and th350 to look at. well that pisses me off i may just be able to use the stock crossmember for now if the trans is located in its original position
my car is a 1985 buick regal. it seems it would be the perfect amount of space if the clamshells were mounted in there OEM position but i followed instruction to move them rearward to the next holes. That was the correct thing to do right? there is enough space to not hit the firewall i believe but the dip stick for trans was my concern did everything look correct in the pictures i posted? i want to thank you for your imput as well i really appreciate it!!!
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NO!!!!! why why why!!! i honestly diddnt think they were that different but i only had a 700r4 and th350 to look at. well that pisses me off i may just be able to use the stock crossmember for now if the trans is located in its original position
my car is a 1985 buick regal. it seems it would be the perfect amount of space if the clamshells were mounted in there OEM position but i followed instruction to move them rearward to the next holes. That was the correct thing to do right? there is enough space to not hit the firewall i believe but the dip stick for trans was my concern did everything look correct in the pictures i posted? i want to thank you for your imput as well i really appreciate it!!!
my car is a 1985 buick regal. it seems it would be the perfect amount of space if the clamshells were mounted in there OEM position but i followed instruction to move them rearward to the next holes. That was the correct thing to do right? there is enough space to not hit the firewall i believe but the dip stick for trans was my concern did everything look correct in the pictures i posted? i want to thank you for your imput as well i really appreciate it!!!
Staging Lane
Joined: Oct 2015
Posts: 89
Likes: 3
From: Northern Idaho
Leaving the clamshells where they're at will put your engine/bellhousing mating plane as close to the stock location as you're going to get. I would try to use the stock TH350 crossmember in that location and shim the rear trans mount up to acheive optimized U-joint working angles. If you get to that point and your trans dipstick tube doesn't fit, modify the tube or use an aftermarket tube like the one from Lokar. If you move the clamshells forward you will severely limit your accessory drive choices.
one question i have is i have a short shaft th400 availiable out of a 2wd late 70's truck ive been told the short output shaft th400 wont work as it wont have enough slip yoke travel.. do u know if this is true??
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ok thanks for the imput, are you an official holley/hooker tech guy or just done this before??
one question i have is i have a short shaft th400 availiable out of a 2wd late 70's truck ive been told the short output shaft th400 wont work as it wont have enough slip yoke travel.. do u know if this is true??
one question i have is i have a short shaft th400 availiable out of a 2wd late 70's truck ive been told the short output shaft th400 wont work as it wont have enough slip yoke travel.. do u know if this is true??
Teching In
Joined: Jun 2015
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Hey guys, since my last visit I've had the chance to go a different route with my setup.
78 el camino
5.3 out of a 00 tahoe
Planning on running a 4l80
With a 4.10 9" gear
And planning on running a 28" tall tire. Planning on a 275/60-15
My question is, I've heard the 80 has a much higher ratio for the 1-2 shift, just wondering if the 4.10 gear 28" tall tire would make up for most of that or not, as always, that's guys
78 el camino
5.3 out of a 00 tahoe
Planning on running a 4l80
With a 4.10 9" gear
And planning on running a 28" tall tire. Planning on a 275/60-15
My question is, I've heard the 80 has a much higher ratio for the 1-2 shift, just wondering if the 4.10 gear 28" tall tire would make up for most of that or not, as always, that's guys
Staging Lane
Joined: Oct 2015
Posts: 89
Likes: 3
From: Northern Idaho
ok thanks for the imput, are you an official holley/hooker tech guy or just done this before??
one question i have is i have a short shaft th400 availiable out of a 2wd late 70's truck ive been told the short output shaft th400 wont work as it wont have enough slip yoke travel.. do u know if this is true??
one question i have is i have a short shaft th400 availiable out of a 2wd late 70's truck ive been told the short output shaft th400 wont work as it wont have enough slip yoke travel.. do u know if this is true??
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Verdad Gallardo I'm the design engineer at Holley responsible for the development of all Hooker LS swap components. The driveshaft length between your TH350 and a TH400 with a 4" extension housing will indeed be different as will the spline count and diameter of the yoke. You should really count on investing in an upgraded driveshaft anyways with an LS swap as most original driveshaft diameters are too small to safely transmit the increased power an LS will deliver to your rear axle.
and just to be clear everything will be built or ugraded to handle 1000 HP or more this is the end plan. the rearend is new moser 9 inch already installed with all Qa1 susp. and the driveshaft will be custom built when im done and the trans will be a race built th400 my harness was already built and purchased so i will not be running 480le but for now i wanted to get the car mobile with what i have kicking around and am just asking what might work. not a budget build by any means but at this point it kinda looks that way haha i will purchase what i need for the th400 to work i thought maybe the th350 with stock driveshaft might bolt up for a quick get me moving solution but its not looking that way haha
i will post my latest progress video to my youtube channel in the next few days (regalman08)-youtube
thanks again for the imput
G-Body-James, take a look at the work Toddoky does, this thread should answer some of your questions.
https://ls1tech.com/forums/conversio...m-preview.html
https://ls1tech.com/forums/conversio...m-preview.html
just looked at that thread and from what i read my column shift linkage is not going to work with my holley stainless headers!!!!! grrrrrrrrrrrrrrrreat
haha one more problem to figure out or in other words MORE MONEY
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Joined: Feb 2013
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the design engineer!!!!! then why havent you designed a crossmember to work with one of gms most common transmissions the th350!!!! or why havent you developed the holley brackets to utilize the factory accesories that were on my camaros LS3??? haha
and just to be clear everything will be built or ugraded to handle 1000 HP or more this is the end plan. the rearend is new moser 9 inch already installed with all Qa1 susp. and the driveshaft will be custom built when im done and the trans will be a race built th400 my harness was already built and purchased so i will not be running 480le but for now i wanted to get the car mobile with what i have kicking around and am just asking what might work. not a budget build by any means but at this point it kinda looks that way haha i will purchase what i need for the th400 to work i thought maybe the th350 with stock driveshaft might bolt up for a quick get me moving solution but its not looking that way haha
i will post my latest progress video to my youtube channel in the next few days (regalman08)-youtube
thanks again for the imput
and just to be clear everything will be built or ugraded to handle 1000 HP or more this is the end plan. the rearend is new moser 9 inch already installed with all Qa1 susp. and the driveshaft will be custom built when im done and the trans will be a race built th400 my harness was already built and purchased so i will not be running 480le but for now i wanted to get the car mobile with what i have kicking around and am just asking what might work. not a budget build by any means but at this point it kinda looks that way haha i will purchase what i need for the th400 to work i thought maybe the th350 with stock driveshaft might bolt up for a quick get me moving solution but its not looking that way haha
i will post my latest progress video to my youtube channel in the next few days (regalman08)-youtube
thanks again for the imput
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Joined: Feb 2013
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I think with some effort you can get the stock linkage to work, we just didn't see it through as part of our project build.
Last edited by user 4737373; Dec 22, 2015 at 09:48 PM.
There's not enough sales volume in LS/TH350 G-body swaps to justify the engineering expense of designing a specific crossmember for that particular transmission. The forward offset of the engine provided by the use of the Hooker engine brackets is so slight that you can use the stock TH350 crossmember in that application by slightly increasing the length of the slot on the center mounting pad of the crossmember with a carbide bit. That is in fact how we set up two G-bodies for use in the engine swap challenge at LS Fest 2014. As for the LS3 accessory drive, it is spaced to far forward of the engine to be able to package it into a G-body without making major compromises to the functional geometry of the drivetrain. The truck, F-body, Corvette and Holley accessory drives can be used with the Hooker engine brackets while achieving optimized U-joint working angles. The LS3 accessories unfortunately will not package into the same space as the other drive set-ups.
so your saying my ls3 wont fit with the stock long belt spacing? even with the holley bracket and long belt alignment kit? it looks like i have miles of room up front the way its sitting in there now...
oh ya why havent you guys developed anything to guarenteed work with the whipple supercharger or the magnusson those are super popular and there has to be a market for that!!!! i have a magnusson on mine and i cant wait to see what challenges are headed my way hahaha
I 2nd Carl at Central Racing Parts. He'll fix you up with exactly what you need and will give you great advice. He's just down the street from me.
...but for now i wanted to get the car mobile with what i have kicking around and am just asking what might work. not a budget build by any means but at this point it kinda looks that way haha i will purchase what i need for the th400 to work i thought maybe the th350 with stock driveshaft might bolt up for a quick get me moving solution but its not looking that way haha
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ya i guess that makes sense if a guy can just use the stock crossmember
so your saying my ls3 wont fit with the stock long belt spacing? even with the holley bracket and long belt alignment kit? it looks like i have miles of room up front the way its sitting in there now...
oh ya why havent you guys developed anything to guarenteed work with the whipple supercharger or the magnusson those are super popular and there has to be a market for that!!!! i have a magnusson on mine and i cant wait to see what challenges are headed my way hahaha
so your saying my ls3 wont fit with the stock long belt spacing? even with the holley bracket and long belt alignment kit? it looks like i have miles of room up front the way its sitting in there now...
oh ya why havent you guys developed anything to guarenteed work with the whipple supercharger or the magnusson those are super popular and there has to be a market for that!!!! i have a magnusson on mine and i cant wait to see what challenges are headed my way hahaha
The truck, F-body/GTO and Corvette are by far the most common OE accessory drives being used in LS swaps and the G-body firewall and steering box dictate where you can locate the engine fore/aft while being able to achieve optimized U-joint working angles...the steering box you use also has a profound impact on what accessory drive components you can use.
Some suppliers move the engine forward and/or up considerably in order to be able to fit a particular oil pan or accessory drive set-up in the car, but that comes with a negative impact on U-joint working angles. The Hooker G-body LS swap system components were designed with completed vehicle functionality/performance being the primary focus of our efforts, not the ability to be able to attach every existing LS engine component to the engine after it was in.
The supercharger kits you mention are no different than any other components in the fact that moving the engine up/forward at the expense of creating negative U-joint angles just to accommodate their installation is not something we are interested in doing. There would be little point in having a supercharged engine in a car with poorly engineered drivetrain geometry and it would seem to make more sense to install the engine in the chassis with optimized functional geometry and then modify the car as needed to be able to install the supercharger.
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What's up jimmyg, that looks like a good option for guys using LS3/L99 engines in their swaps...did you go that route with your car?
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