Thread: Replacing L67 bottom end for L26 bottom end

every thing bolts right up. you will need a tune tho.

Everything does bolt up. But, you will need to change the heads over to L67/L32.

You will also likely need more than a tune, due to the higher compression. Cam, IC, or bigger pulley.

Originally Posted by OcalaGTP

I have a rod knock on my 2002 GTP. I can find L26 blocks everywhere for cheap. I have done some top swap research. Just had a few things i couldn't really find.
Does the L26 block bolt up to the HD l67 trans?
Does the car have to be re tuned ?
Do all the accessories bolt up the same?
Motor mounts?
Any other issues ?
Will the L36 be any better?

The L26 will bolt right up to your L67 trans but you will want to use YOUR L67 flex plate.
Yes you will want to have it tuned. Look into what other mods you want to change/add while you have a tune done.
Everything bolts right up. IF you get a L26 with the aluminum oil pan you will have to get the motor mount for that pan OR grind your horseshoe bracket down for clearance. I just grinded mine down then painted it.

You will have to swap everything heads up from the L67 to your L26. I got a low mileage L26 and used the L26 ICM, coils, all the sensors on my 99. It's very easy.

I would recommend using the flex and Converter from the L26

i wouldn't use a t verter form a un known tranny. it holds a lot of fluid and can contaminate your good tranny if its got metal shards in it.

Yes, the L26 flexplate has both the 258mm and 245mm bolt pattern drilled on them.

Very good to know!!! Glad GM finally learned to make things more universal....