2.5L ST Engine Build Questions

[kugelfischer]

OK, so this is going to be the first of probably many stupid questions, but here goes.
I'm going to start pulling together parts to build my dream engine and I need some input or references to use. I am planning on a 2.5L S/T, twin plug, high-butterfly setup. I expect it will take me a few years to pull everything together, and would like to start searching for a good case.
I don't need a period correct case, I want something that will have a long life and work with the 86.7mm (2.5L) P/Cs
Do I go with a 7R, or something else? Would the choice be any different if I decided to go with a 2.3L?

Thanks
K

[304065]

Yes get a 7R if you want the mag case

86.7x 70.4 gets you 2493cc, sure that's what the factory did to get it under the limit, but why not 90 or even bigger, with a shorter stroke? You have a blank canvas and the time to get it right.

[MBruns]

Being that you have a choice, I would start with an alum. 2.0 case, they have more strength than you will need, the mag cases are a bit lighter but take so much effort/money to prep. and then they still have issues, after the last few full house 2.5 engines that had case failures I just won't start a small bore project with a mag case.

My .02, Mike Bruns JBRacing.com

[kugelfischer]

Thanks for the advice. I'd like to avoid the Mag case issues altogether.. I already have enough of those with other engines.
Would there be any reason I couldn't go with a 3.0L Turbo (Al) case, 90mm cylinders and say a crank from a 2.2l for the shorter stroke?

[Steve@Rennsport]

Originally Posted by kugelfischer

Thanks for the advice. I'd like to avoid the Mag case issues altogether.. I already have enough of those with other engines.
Would there be any reason I couldn't go with a 3.0L Turbo (Al) case, 90mm cylinders and say a crank from a 2.2l for the shorter stroke?

With custom cylinders to make your displacement, thats a VERY good way to go.

You'll need to spend some money on those heads to make the power you want.

[356RS]

Originally Posted by kugelfischer

Would there be any reason I couldn't go with a 3.0L Turbo (Al) case, 90mm cylinders and say a crank from a 2.2l for the shorter stroke?

Great case, but then you might as well use the larger spigot bore of the 3.0 case and go with a set of 95mm pistons. You will also need the 3.0SC heads. So your in the 2.8SS area now.