LS Swap: Dimensions

[66gmcguy]

Hello all. Does anyone know if you have to move the transmission forward or backward when doing an LS swap in a truck that previously had an SBC in it? I know there are mounts that allow you to slide the LS basically wherever it fits best, but I want to know if this puts the back of the block (where the bellhousing mounts) in the same location as the SBC.

I have a 73 C10 that currently has a Vortec 350 in it, and a TH350. I've decided to swap the TH350 for the new TKX transmission. I'm ready to do the TKX swap now because I really want a manual transmission and overdrive since this truck will be driven daily. To do the swap, I have to move the crossmember back, shorten the driveshaft, and cut a hole in the floor for the shifter, but I've also been toying with the idea of doing an LS swap. I can wait a while to do the LS swap since my engine currently is running really well, but I know I'll eventually want an LS. What I'm trying to avoid is having to move the the manual transmission and thus have to patch the floor and recut a new hole, get a new driveshaft made, etc.

[mongocanfly]

the ebay plates is used on my c30 swap locates the rear of the LS in the same spot as a sbc...
the

[66gmcguy]

Originally Posted by mongocanfly

the ebay plates is used on my c30 swap locates the rear of the LS in the same spot as a sbc...
the

How much clearance is there between the heads and the firewall?

[mongocanfly]

not sure exact, but i can squeeze my hand in there..and ive got big hands..
i can look tomorrow and see how much.

[66gmcguy]

Originally Posted by mongocanfly

not sure exact, but i can squeeze my hand in there..and ive got big hands..
i can look tomorrow and see how much.

That would be awesome. Any possibility I can get you to send me a picture of it? Thanks!

[mongocanfly]

of the clearance ?

[66gmcguy]

Originally Posted by mongocanfly

of the clearance ?

yeah if you don't mind

[kipps]

Either the SBC or the LS can move forward if you convert to electric fans, but the LS is a little shorter, so it can move forward further. Three inches forward and one inch upward is very common, using Tejas LS-swap mounts.

The LS can also sit in the stock SBC location. There will be no more than a finger width of room in some places between the heads, block, and the firewall. You also won't be able to run the stock LS AC compressor. You can fit that compressor in place if you use the Tejas mounts, though.

[TrybalRage]

All depends on the mounts. I also used Tejas, and used a 4L60E as well. Just moved the trans crossmember a little. Tons of room between the motor and firewall.

[mongocanfly]

Gmcguy,
without pulling the covers off the engine, I couldnt get a clear pic of the clearance ..
But it's a little over 2 fingers width between the pass head and the firewall..so I'm gonna say a little over 2in..theres a little more on the drivers side..I think the bellhousing would hit before the engine would if I went back..it could go further forward with no issues

[66gmcguy]

Originally Posted by mongocanfly

Gmcguy,
without pulling the covers off the engine, I couldnt get a clear pic of the clearance ..
But it's a little over 2 fingers width between the pass head and the firewall..so I'm gonna say a little over 2in..theres a little more on the drivers side..I think the bellhousing would hit before the engine would if I went back..it could go further forward with no issues

No worries. It sort of sounds like the best thing to do is move it forward. So that sort of clears up that I should swap the engine and transmission at the same time rather than swap the trans now, then engine later. Thanks for your time brother!

[85/Silverado]

The only place mine had fit issues was the 2" headers on the passanger side.