[911st]

Most the time with stock gears a 2.4E is faster than a 2.4S. However, the S feels more entertaining. I think the 1973 R&T reported the E was faster to 60.

I would guess the limit of the 32mm 2.4T stacks is around 200hp no mater the build.

Building a 2.4E requires a new space cam and MFI pump redo. So dose a 2.7RS motor. This can add greatly to the expense.

As to how far you can stretch the stock T pump. A 2.5 should not require many clicks richer to make it work well.

On the lower cost side having the cylinders bored out to a 2.5 and get a set of J&E pistons for around 9.5/1 CR could make for a nice running car keeping the T cams. I would put an E rotor in the dist in it to expand the red line to 7100rpm. Then add a nice single or double pipe sport muffler and dial things in on a dyno.

One might be able to build a 2.7T motor and adjust around the pump but you would not know until you try it. It would not scare me to try this but I have played w MFI pumps a bit.

On the upper end, I believe the plastic 2.4 T stacks can be bored to about 36mm to support a 2.7RS motor but that is it. I would not be afraid to hone out the stacks and mill the bottom of the throtle bodies to 35 or 36mm myself if the shafts seem tight. Or they can be sen out to a known builder. I knew one 2.8 SCCA racer that ran 35mm ports on a 280hp+ motor very successfully so they do not have to be much of a limit.

As Porsche used 36mm stack on there 3.0RS motor building a stock appearing 2.9RS MFI motor using Nickies' cylinders or 2.8 using bored and plated 2.7 cylinders could be a possibility. I ran a modified S cam on a 2.8 I had w a 2.7RS pump and it ran well. The mod S cam I think fills in the HP curve a bit. This should move your TQ from 148 to over 200# and your HP to around 240 or so. My 10.5 CR 2.8 twin plug was around 260fwhp using factory 2.4S stacks.

As noted, cost is the only limit.