Small displacement twin turbo for pca gt4
 

I was at Mosport this weekend racing in GT4s.

One of my competitors was there with a very nice motor setup that I would like to consider replicating for myself.

He had a twin turbo setup using a 3.6L case (I crawled under and looked)

Now the limits of gt4 is a displacement of 2.8L and a turbo adds a multification factor of 1.3, so the largest displacement turbo that you can build and still be in gt4 is 2.15.

I have toyed with the idea of building myself a nice turbo motor for the class. I had never thought about starting with a 3.6L though. I have plans for a sleeved down 3.0 to give the 2.8L displacement.

How hard is this, what would I have to do. De-stroke, custom pistons, what else.

This motor seemed to do extreemly well for him. Last year his fastest time was 1:37 with a 2.8L na, now he was able to hit 1:31.

Thanks

Ed

I have seen this conversion from other cases. There is a second compeditor doing this as well from a 3.0L case I believe, but this is the first one I have seen from a 3.6L case.

Ed

Why not build one off an early 2.0L aluminum case? They are super sturdy, especially when suffle pinned.

This was my thought when I was putting a plan together. Hard to find the 2.0 sand cast cases though.

This is why I was interested in the 3.6L case. Seems as though there would be many technical dificulties in doing this.

The heads do not seem like they would cover up a sleeved down piston. The valves would be interfered with.

If I can get around these problems, and it looks like someone else did...

Ed