LS1/T56 in 68 bird with ATS plates, you can use your stock 400 cross member!
02-27-2008, 10:39 AM
#1
LS1/T56 in 68 bird with ATS plates, you can use your stock 400 cross member! Ok here's a few things i picked up while installing it. The setup was
ATS plates
Polyurethane SBC mounts (Autozone $29.99)
T56 bolted to engine
#1 When installing new frame mounts, leave them loose as you will NOT tighten them down in the right spot. Also leave the SBC mount on the plate loose until you get the holes lined up.
#2 ATS plate are extremely high quality. Although, the 2 rear bolts were too long i just used the factory 2 bolts i had. All my bolts were the same length as the one used to bolt the SBC mount through the ATS plate together, maybe a packaging error?
#3 stock exhaust manifolds won't fit with the ATS plates. Alteast in my case. I have a manual steering box and it was hitting which screwed me real bad because i was using the factory exhaust manifold to wrap a strap around to lower the engine/transmisison in so i had to drop it, unstrap it, removed it and restrap it. It was so extremely close that i think it should have fit. I got the SBC mount bent, and lined up and the bolt through one side and after an hour of trying to get it through the other side just couldnt make it work.
As far as using the factory TH400 cross member you can! It requires a little modification but it works. I liked where mine bolted better. I'll try to get a pic of it when i go to re-bolt it on.
First take your TH400 crossmember. Cut it right AT the holes. As in right where the holes are the very tip of the circle of the hole straight through to the next on each side. This will now allow your crossmember to fit with less than an 1/8" on either side between the frame rails. Doing this now make your transmission mount off centered (i have no idea why) i used a grinder to grind the weld off and pulled a tape from each corner to center the mount. I got 15 1/4" on center which lined up absolutely perfect. The two holes from the T56 mount line up exactly with the two holes from the TH400 mount.
Now when you hold this up there to check clearence this is the MOST IMPORTANT part. Hold it up there BACKWARDS. and it fits. The dip down in for the TH400 is almost perfect. You're not done yet you're just checkin clearences right now though. If all that is good take and cut yourself 2 pieces of angle iron about 6" long. If you dont have SFCs then you only need the width of the cross member. I used 1/4" 2x2. Lowes, home depot, Ace, or tractor supply sells it. Weld these FLUSH with the ends of the TH400 cross member (right where the holes were) and with the 90 degree facing down. So basically your TH400 mount is sitting on top of the angle iron and the angle iron is sitting flush with your frame rail and its facing down so you can drill through it.
The top of the cross member is about 1" from the floor pan of the car and I dont have the exhaust on yet but from the pictures i have see it should fit. with my setup i have subframe connectors so some of the after market crossmembers would require me removing them to get to bolts. With where mine mounts The 6" piece of angle iron stradles the frame rail and subframe connector. I have 3 self tappers in there on each side of the angle iron (it started to rain needed to move the car) but they will be bolts. 1 bolt at front in the subframe which you can reach from the access hole left to reach the body mount. 1 bolt in the center that bolts the subframe connector to the subframe which is accesable through the same body mount hole. The 3rd bolt i have going through the subframe connector. Which is also reachable through the same body mount hole.
Basically this crossmember has now bolted my frame rails together then also the 6" piece of angle iron on each side has bolted my subframe connectors (bolt on) directly to my front subframe. I'll get a picture but all i have is my camera phone as my digital camera broke when it slid off the trunk during intense hammering.
ATS plates
Polyurethane SBC mounts (Autozone $29.99)
T56 bolted to engine
#1 When installing new frame mounts, leave them loose as you will NOT tighten them down in the right spot. Also leave the SBC mount on the plate loose until you get the holes lined up.
#2 ATS plate are extremely high quality. Although, the 2 rear bolts were too long i just used the factory 2 bolts i had. All my bolts were the same length as the one used to bolt the SBC mount through the ATS plate together, maybe a packaging error?
#3 stock exhaust manifolds won't fit with the ATS plates. Alteast in my case. I have a manual steering box and it was hitting which screwed me real bad because i was using the factory exhaust manifold to wrap a strap around to lower the engine/transmisison in so i had to drop it, unstrap it, removed it and restrap it. It was so extremely close that i think it should have fit. I got the SBC mount bent, and lined up and the bolt through one side and after an hour of trying to get it through the other side just couldnt make it work.
As far as using the factory TH400 cross member you can! It requires a little modification but it works. I liked where mine bolted better. I'll try to get a pic of it when i go to re-bolt it on.
First take your TH400 crossmember. Cut it right AT the holes. As in right where the holes are the very tip of the circle of the hole straight through to the next on each side. This will now allow your crossmember to fit with less than an 1/8" on either side between the frame rails. Doing this now make your transmission mount off centered (i have no idea why) i used a grinder to grind the weld off and pulled a tape from each corner to center the mount. I got 15 1/4" on center which lined up absolutely perfect. The two holes from the T56 mount line up exactly with the two holes from the TH400 mount.
Now when you hold this up there to check clearence this is the MOST IMPORTANT part. Hold it up there BACKWARDS. and it fits. The dip down in for the TH400 is almost perfect. You're not done yet you're just checkin clearences right now though. If all that is good take and cut yourself 2 pieces of angle iron about 6" long. If you dont have SFCs then you only need the width of the cross member. I used 1/4" 2x2. Lowes, home depot, Ace, or tractor supply sells it. Weld these FLUSH with the ends of the TH400 cross member (right where the holes were) and with the 90 degree facing down. So basically your TH400 mount is sitting on top of the angle iron and the angle iron is sitting flush with your frame rail and its facing down so you can drill through it.
The top of the cross member is about 1" from the floor pan of the car and I dont have the exhaust on yet but from the pictures i have see it should fit. with my setup i have subframe connectors so some of the after market crossmembers would require me removing them to get to bolts. With where mine mounts The 6" piece of angle iron stradles the frame rail and subframe connector. I have 3 self tappers in there on each side of the angle iron (it started to rain needed to move the car) but they will be bolts. 1 bolt at front in the subframe which you can reach from the access hole left to reach the body mount. 1 bolt in the center that bolts the subframe connector to the subframe which is accesable through the same body mount hole. The 3rd bolt i have going through the subframe connector. Which is also reachable through the same body mount hole.
Basically this crossmember has now bolted my frame rails together then also the 6" piece of angle iron on each side has bolted my subframe connectors (bolt on) directly to my front subframe. I'll get a picture but all i have is my camera phone as my digital camera broke when it slid off the trunk during intense hammering.
02-27-2008, 12:45 PM
#2
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fyi, TH400 mount was off-center from the factory. TH400 was only used behind big blocks, and the big block frame mounts offset the engine to the right for exhaust manifold clearance to the steering box. The TH400 crossmember is offset to match.
02-27-2008, 01:07 PM
#3
Wow thanks for the info i never knew that. Makes sense though. I thoguht i was going crazy and cut something wrong.
I went out and bought a new camera haha. It's a very rough crossmember for now as it's not painted nor bolted straight as i said it started to rain so it was just to hold it while i pushed it back inside of the trailer. I figure it'll help strengthen my chasis and didnt cost me any money. Maybe an hours time to make.
It's a little gawdy but works and structurally better IMO
I went out and bought a new camera haha. It's a very rough crossmember for now as it's not painted nor bolted straight as i said it started to rain so it was just to hold it while i pushed it back inside of the trailer. I figure it'll help strengthen my chasis and didnt cost me any money. Maybe an hours time to make.
It's a little gawdy but works and structurally better IMO
02-27-2008, 04:57 PM
#4
I got it all bolted up and was able to get a good pic of it. It's still not painted and by no means beautiful but it seems to work well. I used 1/8" 2x2 angle iron, not 1/4" my mistake. It's also a little crooked but that's only because i welded the mount at a slight angle, its level with the transmission mount. It's actually at the exact same mounting height as the stock location (that little ledge for it to sit on) Looks like there will be plenty of room for exhaust to clear although I'm having a 3" X pipe with side exits im installing so im eventually going to have to lower the exhaust anyway.
09-30-2008, 08:51 AM
#7
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LS1 Studebaker You guys that have installed a T56 in your Camaro, what clutch/brake pedal set up have you used. I have one from a '95 Camaro that I'm thinking of using but the position of the clutch master cylinder is weird, requiring some bracket fabrication. If any of you have addressed this problem I would appreciate some help. Thanks.
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09-30-2008, 06:00 PM
#8
I installed factory 67-69 manual pedals. I used a stock 02 LS1 clutch master cylinder and slave cylinder. I had to shorten and re-weld the clutch slave cylinder rod to make it fit onto the stock clutch pin location. It's worked great so far.
