Compression on Turbo motors?

[santamaus]

What sort of compression would you want on a turbo motor to allow it to take less than optimal (say, 89 octane) pump gas?

If you wanted to build a 3.1 stroker turbo, what choice of parts would you go for? Most of the 3.1 builds seem to have a fairly high (9.5+) compression ratio, which doesn't seem to be a good idea for a forced induction motor. I would definitly like to keep an L6 core in the car, and have toyed with the idea of building a 3.1, but they all seem to be normally aspirated. Why not go the full route, and drain every last bit out of the engine that is possible (without putting a bomb in the front of the car!)?

I don't have any problem with Nissan parts from something else, like the obvious diesel crank and alternate pistons, but I obviously need to do something other than shim the hell out of the head to lower the compression a bit. Also, for added complexity and cost, anyone know of the twin turbo L6 that's on the site? Quicker spooling would obviously be nice. Also--I think I remember seeing a supercharger for the L6 a while back--anyone have a lead on that?

Any thoughts would be appreciated.

[lordbiotree]

There's a guy over a Zhome.com who has a supercharged L6. The engine and supercharger was custom built himself.

Stroking and running a turbo is just plain out stupid. Don't get me wrong. If your rich enough go for it. The cost would be in the tens of thousands of dollars.

Basically it is whichever you like better. Do you like a N/A over a turbo? Are you trying to get power for cheep? Turbo is the most economical choice. You get the most power out of you money.

Naturally aspired are my preference. I don't have enough loot for one.

Second.

Do you plan on doing all the work yourself. A stroker takes seasoned personal. For the DIY your much better buying a turbo L6 push up the boost and enjoy.

[sblake01]

Also, for added complexity and cost, anyone know of the twin turbo L6 that's on the site? Quicker spooling would obviously be nice.

Any thoughts would be appreciated.

All I have ever seen of that twin turbo is the picture. Does anyone know if they ever made it work? Exhaust manifold, electronics, etc.? The cost would be ridiculous and I don't know, judging from the two pictures I've seen of the engine on a stand, if you could even get that to fit under the hood of a Z.

[PrOxLaMuS©]

works, and runs....

the yellow car runs 11's in the 1/4 mile

[santamaus]

Tens of thousands? Hmm..

If I were to build the engine using no parts I currently own, how much more would building a stroked turbo engine cost versus building an L28 turbo engine?

I still need a block, crank, pistons, rods, head, valves, cam, etcetera--it's only a matter of size. If I want good, rock solid performance out of it, I'm going to want to balance it either way. As far as pieces go, I need no more pieces for a 3.1L stroker than a stock L28 (well, other than another 300cc!).

If I use a turbo, again, I still need the same extra pieces for either displacement engine.

So... where am I missing the extra cost? If I were to go locate a 280zx turbo motor, and snag that and drop it in, I could see where the used motor is going to be cheaper, but if I'm tearing it down and detailing all the pieces, where is the difference apart from a little more block machining?

Please understand, I'm not trying to be difficult. I just do not see any real diffence between tearing either engine down, machining either for proper balance, and putting them back together again. Apart from crazy pipe dreams like dropping a Q45 engine, an RB, or an XJ12 motor in there, I'd like to keep the L6 motor in there, I'd like to pull as much power out of it as I can, and I'd like it to last until I'm tired of driving Zs. Since both more displacement and better cylinder filling both contribute to better power, and they aren't mutually exclusive, building one monster engine seems to make the best sense. Besides, we can't let Rebello have all the fun, can we?

[Dan Baldwin]

No reason not to do a stroker turbo. You would want to get custom forged pistons for it, though, so there's some added cost (I was quoted $900 from JE). CR with a P90 head and 2mm gasket comes to ~8.9:1 with KA pistons, but with custom you could make it lower quite easily.

[sblake01]

works, and runs....

the yellow car runs 11's in the 1/4 mile

For what that must cost, I'd want to be quicker than 11's! :disappoin