Recently, I siezed my 97 Regal gs with the L67. Oh no!

Actually, this just gives me a reason to rebuild with forged internals. 8D.

I have an idea, and I'm curious as to some opinions.

I want to take twin turbos, prolly nissan, one per manifold, and twin turbo, twin charge my regal.

I'm thinking of plumbing,

Filter/Turbo/
Intercooler/Y/Throttle Body/Eaton M90/Lower Intake Manifold
Filter/Turbo/

Thoughts? Concerns?

You'd get more bang per buck if you beefed up an L36 and twin turbo'd it and top swapped it. The L36 has a higher compression ratio than the L67.

But oh wait. First launch and you'll toast the trans. I don't think your going to find strong enough internals to handle that much power.

Only looking to push a total of 9 to 10 psi.

Then why the need for 2 turbos and a supercharger?

You can get about 12psi with a 3" pulley on a L67. Stock M90 is about 6-8 psi on a healthy engine.

At that boost level, even a carefully chosen single turbo should work. But why beef the bottom end if not for more boost?

I'm looking for a one of a kind rig. So the twins and Sc are mostly for awe factor.

I plan on putting a boost control on my dash, so I can push 15 to 20 when that ricer rolls up at the stoplight.

Also, that eaton m90 loses pull on the top end, the twins wont. But the twins don't have pull on the bottom end, but the SC does.

My biggest concern is tuning. I assume the MAF should be between the intercooler and the SC. What about the o2 on exhaust? Downstream from turbos before cat? Or on manifold before the twins?

I plan on getting a flashed ecu from 3800 performance. I assume that toy will need more tuning past that. How to tune?

I'm also wanting a less restrictive exhaust, that is just as quiet as stoxk. How though? Larger pipes with quieter muffler?

you should try to find some one that tunes locally on the dyno. ask them if the stock computer can be used or you have to get some stand alone controls with boost referenced timing and fuel. the answer to that might determine sensor placement. also not sure how you are going to do the maf, the 3800 one is in the tb, might have to just get a bigger tb with a maf in it. all that will have to be tuned too.

In a boosted environment, MAF always sits behind the throttle body.

Awe factor? Don't know how your going to mount 2 of them anyway.

IMO, your wasting your time, resources and money into putting a second turbo in. And probably will cause more issues being inline on the exhaust.

Being a turbo/SC environment, prepare to cough up $600 for HPTuners Pro. No mail order tune will work in your setup. You will need to constantly log data, adjust, retune, log, adjust, tune etc.

Based on the questions your asking, your knowledge of automotive systems seem lacking. Might I suggest maybe having a shop do this or start out with something different? Your going to need a lot of experience in just basic tuning before even getting into something like this.

Make up your mind, are you wanting 9 to 10 psi or 15-20psi? I thought the second turbo was for "shock and awe" effects and not actually working?

Either your here to troll, or your just way out in left field somewhere and have no clue as to what your doing.