Yes as far as I can tell the heads are the same. I've confirmed this from a site I found comparing the two and also the fact that both part numbers are the same.

4T60-E HD - Same as 4T60-E except with a few heavy duty parts (mainly final drive gearset) for supercharged 3.8l V-6 application. This is the only reference to the specifications I've been able to find, at all! All other specifications refer to the (presumably) standard trans. Thats something that'll have to be looked into further.

I've never priced it but I can't imagine the pulley brackets and such costing very much. I can't imagine the PCM being that big of a deal either, nor the need for a custom one. I'm not saying cut corners but many of you do the boost control bypass and never think twice about it...well you've nearly reduced the PCM to that of a naturally aspriated.

A question I do have, how different is the connectors for the PCM? Is there a major difference in that you couldn't simply replace the na PCM with that of a sc? Obviously it'll be without the bcs, but is it even possible? I've read once the proms are the same part number so it got me wondering. Other parts would also have to follow, namely fuel injectors and MAF sensor but that was a given.

The MAF is what basically controls the injectors, so it would either have to be swapped or a a/f calibrator put in place. I posted instructions on how to build the Tech Edge unit in another thread..if you're low on money but rich on knowledge

I'd say so far in the whole scheme of putting forced induction on a naturally aspriated we have it about the easiest. Most others have to deal with high compression ratios, weak bottom ends, major clearance issues, and can't go to a junkyard and grab almost every part they'll need to do this. Heck 95% of the parts are probably for sale on this forum right now. I've seen several posts offering these parts up on the cheap. Heck I'm looking at buying another supercharger for $75, the lower intake isn't much and neither is the injectors or PCM if you ask around...The brackets? I'd think most that are scraping their engine would love to make a buck off that because who else is going to buy it. I'm rambling though haha sooo much more homework to do.

Oh it'* not a cost issue with all the small bolts and such. Just getting all those odds and ends together.

AFAIK the pcm connectors are same engine to engine, however the BCS/MAP isn't wired into the connector for an L27 stock. Spiral told me series II connectors were the same, when he did his swap, so the ZZP wiring kit "should" work. ALthought a full engine harness could cost that much too used, so it'* not a big deal...

This thread has relit my fire into proving that damned techinfo wrong.

Things i know i still need
Gaskets, gaskets, gaskets
Belts
balancer
misc hardware
maybe the secondary alt bracket
wiring
fuel curve setup.

I'm not sure an AFC calibrator will solve the fuel curve thing by itself. It'* not just a single curve, but a series of maps. In addition, there are other parameters. The SSEi develops it'* torque much lower down. Are we sure they shift at the same point as the L27 cars?

Then on top of that, you're running a non-hd gearset. You may want to LIMIT your shift points to protect that.

My car shifts ~5000 RPM and 40~42MPH.

Doesn't the Mini AFC have 13 adjustment points on the curve? In reality a $35 GMTuners chip would be easiest, cheaper....

We need to do some shift point comparisons. Throttle % has an effect, so we'll have to do gentle throttle and WOT. My trans isn't a good candidate for this.

Not yet, anyway.

The SSEi PCM has retarded shifting to protect the trans. I'm not sure that programming goes into the L27 PCM'* or not. Shifting comparisons need to be done with and without performance shift on the comparison L67. It would be nice to have at least 2 L67'* and 2 L27'* do this. Preferably those that have access to scantools.

Its not nice to make fun of shifting

As was stated the stock rating for the 60-E is 280lb/ft of torque. I'm not sure how much more the HD will handle but I can't imagine too much more as even with the HD the PCM still pulls timing and fuel before shifts.

The '92 SSE makes 170hp at 4800rpm and 220lb/ft of torque at 3200rpm. The '92 SSEI makes 205hp @ 4200rpm and 260lb/ft @ 2600rpm. This would mean the stock shift points are well outside its maximum torque and power range especially IF the naturally aspirated is set to shift higher. Since the SSEI makes its power so low its almost impossible to shift low enough to avoid the larger chunk of the power, the only real option is to (within reason) shift higher so you catch it on the down stroke. Shifting at a lower RPM will put it deeper into its powerband and negate the reasons for doing such.

Food for thought

Well...seems this thread lost a lot of momentum

If you guys still have my video i made a few weeks ago yo ucan see my WOT shfit points
Otherwise i can do a few new ones.

The only difference in part numbers between the Supercharged (vin 1) and TPI (vin L) versions of the 3800 besides the intake and assy belt drive system was a different connecting rod part number.