Thread: GTP Question New To The 90 Degree Motor

ok i just bought a 2005 grand prix which is the base L26 model and im new to this forum

So everyone knows im a GM certified tech and know alot about cars but not much bout the 90 degree motors so bare with me


Ok sorry question is which is a better to do the top end swap which ive read alot about today on here or a motor swap... i ask because with the 04+ they use the electronic throttle body and i dont know what exactly will bolt to that... plus i dont know how much diffrentt the harness is from the L26 to the L32

so yea help me out here

hmmmm, I thought to myself reading this, this is an easy question, then you brought up the electronic throttle. I know there are adapters to run the Gen V blowers on the L67's and other Gen III blower equipped vehicles. Since you already have the electronic throttle I would think it would just be a matter of getting a Gen V blower and LIM, crank pulley and so on.

However, this is not exactly my area of expertise so I'll have to defer to someone that has actually done the swap.

Originally Posted by 19SE92

Your better off doing the Whole swap. Because I've never heard of someone top swapping an 04+ L26 yet.

http://www.grandprixforums.net/f18/n...rged-6036.html

Top swapping the L26 is the same as top swapping the L36, just you have to use Series III parts instead of Series II. 05+ L26 rods are plenty strong, so there's no real reason to want to go for the full L32 block unless you have to.

You'll need...

Heads
LIM
TB
SC
Crank pulley
Idler pulleys
Assorted vac lines, BBV wiring, MAP adapter (most likely), and probably reprogramming

You can try to use the L32 computer, but it might be better to have someone with a tuner iron it out for you. Don't forget to have some intake and exhaust work done too. The higher compression of the L26/L36 blocks will make them more prone to knock so you need supporting mods to help fight this. The part I'm not sure about is how to convert from a return fuel system to a returnless fuel system.

Don't the L26's have practically the same return-less fuel system as the L32's? Or am I mistaken?

I thought the L26 used a standard return fuel system. I could be wrong...

Just double checked and both the L26 and L32 have return-less fuel systems, so no need to change the fuel system other than the fuel rails.

The data I have on the L32/L26 specifically says that the L32 is returnless but it never mentioned the L26 in that section. Oh well, must've been an omission.

You can run the same size pulley, you just have to have the supporting mods like I was talking about earlier. Headers, catback, intake, cam or rockers, tstat, etc.