The R-ish motor plan part 2

[pieterk]

The SWB donor with it's very sweet running 2.2E and MSX gears (thanks John!) has arrived.

And I'm finding more clarity with the projected build ideas.

As much as I wanted to build a 2.8S or 2.7SS, now that I've been driving the car, I just don't need that much power in this car. In fact, I think I'd risk having an unbalanced package overall; too much power through a 901 on relatively narrow tires with an ultimate target weight of under 2,000 lbs.

A 2.7RS or 2.5SS will be more than fine, and the parts are fairly available and not too expensive. I'll save the really hot parts for the 2.2 rebuild and/or a 2.8SS or 3.2SS for the track car.

So, I'm going to pick up a 7R, look for a good set of used Mahle cylinders, and order a set of JEs from Charles with a target CR of 9.5:1. In the interest of economy, I'm staying with single plug for this. I'm thinking Mod-S or DC40s, or maybe, DC62s, although the latter might be too aggressive.

The issue I'm trying to resolve now is whether to use a 66mm crank for a 2.5SS, or just stick with the 70.4s and build a 2.7RS.

Thoughts? Am I increasing my build aggravation and cost substantially by dropping in a 66mm? And which rods will I need to mate a 66mm crank with custom JE 9.5:1 pistons in 90mm Mahles? Either stock 2.2s or 2.4/7s would be ideal, if either fit correctly. Again, for this motor, economy (a relative term, I know) is becoming a big factor, so I'm loath to have to source exotic rods.

[356RS]

Sounds like you have eyerything for a 2.5SS except the pistons and cam. I think the 2.5ss would match your SWB very well and would be lots of fun to drive. DC-40's and 9.5 comp........sweet.

[rvanderpyl]

I have the same issues. Except I had already ordered and received a set of JE Pistons designed for 9.3:1 on the 66mm crank as I was going to use partw from my 2,2 for the build. Then I picked up a 2.4T and a set of twin plug heads. Near as I can figure if I use my pistons on the 2.7 crank I will end up with around 10.5:1 CR which I can handle with the twin plugs.

Now I just have to decide what to do for fueling. At first I thought I would use the 2.4T's MFI as a basis for the 2.7, but then decided the cost of rebuilding everything to go that way was just to much. So I started on a EFI project and sold the MFI stuff. But then in one of those twists of fate that make you wonder I discovered, and bought a complete MFI system a guy was selling from his 2.7 S cammed motor. Now I don't know where to go. For the EFI I have a Electromtoive Twin Plug Setup so my fuel control and spark is handled. But I haven't proved out my throttle body setup to be workable. For the MFI I will have to find a few parts I am not getting, but the main issue is I need a twin plug ignition system. I could just use the ignition component of the Electromotive, but that isn't exactly going to match in with the rest of the 'old school' MFI system. So now I am going to need a 12 plug distributor. Kind of like the one I sold when I decided not to go MFI

I wish I had more time to work on the car so it would be done and I couldn't keep making these direction changes.