For you GS guys this is your question?

[Joaltava]

Will it be better to turbo the DOCH 4g64 engine or swap it?

[seth98esT]

Swap it or rebuild it. Its not made for boost, just like the '64 SOHC is.

[Joaltava]

if its rebuilt we can turbo it correct?

[4-G-rim]

<div class='quotetop'>QUOTE(Joaltava)</div><div class='quotemain'>if its rebuilt we can turbo it correct?</div>

Yes..if you rebuild it with internals that can support higher boost. Yes...you can bolt on a turbo on a stock DOHC 4g64 but from factory they run at a 9:1 compression..which is good to handle 8-10lbs of boost. If you want to run higher psi you will have to run lower compression pistons and possibly stronger piston rods to whatever suits your budget and power goals. Now...this is something you can think about too, higher compression on low boost doesn't neccesarily mean lower numbers.Yes..granted a high compression motor has a limit to where you can push it before you have to reinforce it internally to handle higher boost BUT you have the benefit of having your power from the get go where turbo lag is not a real issue unlike a lower compression motor. Look at this way. (Till we there is actual dyno numbers...this theory is for right now hypethetical) A stock 4g63 at 14lbs of boost is claimed to make 210 hp and around 200 lbs of torque. I believe a stock 4g64 at 8-10lbs of boost will make the same horsepower and more torque due to its higher displacement. This is theory..but till I can prove or someone else can prove this theory is true.

[DOHCstunr]

10.5:1 compression on the GS motor

[DOHCstunr]

the key is that with higher compression you run a higher risk of knock/ predetonation due to increase cylinder pressures, and the static compression goes up under boost. but if you have some kind of knock dependant timing control, then you would be able to do it.
shit, they twin tirbo stock 350z motors and those aren't exactly low compression.

[know_fun]

<div class='quotetop'>QUOTE(4-G-rim)</div><div class='quotemain'><div class='quotetop'>QUOTE(Joaltava)</div><div class='quotemain'>if its rebuilt we can turbo it correct?</div>

A stock 4g63 at 14lbs of boost is claimed to make 210 hp and around 200 lbs of torque. I believe a stock 4g64 at 8-10lbs of boost will make the same horsepower and more torque due to its higher displacement. This is theory..but till I can prove or someone else can prove this theory is true.</div>

i was talkin wit someone and they said this theory is correct. more torque bcuz of the displacement. more gas on lower rpms

[Faction]

<div class='quotetop'>QUOTE(DOHCSTUNR)</div><div class='quotemain'>the key is that with higher compression you run a higher risk of knock/ predetonation due to increase cylinder pressures, and the static compression goes up under boost. Â*but if you have some kind of knock dependant timing control, then you would be able to do it.
shit, they twin tirbo stock 350z motors and those aren't exactly low compression.</div>

You mean 300zx? I went cross eyed there

[El Chote]

I think he means 350zs. People do twin turbo them and stock compression on them is 10:3:1 if I'm not mistaken.

[DOHCstunr]

<div class='quotetop'>QUOTE(Faction)</div><div class='quotemain'><div class='quotetop'>QUOTE(DOHCSTUNR)</div><div class='quotemain'>the key is that with higher compression you run a higher risk of knock/ predetonation due to increase cylinder pressures, and the static compression goes up under boost. Â*but if you have some kind of knock dependant timing control, then you would be able to do it.
shit, they twin tirbo stock 350z motors and those aren't exactly low compression.</div>

You mean 300zx? I went cross eyed there</div>
yeah thats what i mean 350z's and g35 coupes. greddy has a bolt on twin turbo kit, and other company's make blowers for it. When i say they turbo stock 350 z's, i mean they turbocharge stock internals.
with knock dependant timing retard, the possibilities are soo much greater.

[grasshopper]

The GS does retard the timing if it detects knock, according to the service manual.

RPW also turboed a Magna with 10.5:1 pistons and a decompression headgasket to bring the CR down to 9:1.

So, I don't think turboing the stock motor would be much trouble, though max boost would still be hindered by the limitations of the internals.