massive turbos in rb26

[lbreaud]

i dont know if you all have heard of the bugatti veyron, but that thing is runnin on four turbos. i was wondering if anyone has attempted any sort of setup like this in a skyline. i realize that bugatti had these on a W16 (just a few more cylinders than the inline 6 haha). besides for the insane amount of money you would have to put into the engine components (supposing you replaced all stock parts besides the block i guess) and the relative size of the engine, do any of you think this quad turbo setup might become a reality?

[tazdev]

Originally Posted by lbreaud

do any of you think this quad turbo setup might become a reality?

not on the inline 6 engine there just isn't the room for 4 turbos, may work on a v6 but again space would be an issue

[SkylineUSA]

2 turbos can create more than enough power to split the block!

[lbreaud]

the only problem that i see with this setup would be space in the engine bay and the actual size or capacity of the engine. you would have to lower the engine to compensate for the extra space you would need. the block would also have to be extremley strong. the best ive heard of is an aluminum block, but you could possibly get one forged from titanium (hopefully, cause you would need something insanely strong for the amount of power this engine would make). im also assuming practically all of the stock components would be replaced with performance ones. this being said, i dont think it really has to even be an rb engine. a small block v6 might work if you made the space....

[SkylineUSA]

Why bother?

Waste of time and money.

[nismo_power]

i thnk you should think about practicality. 4 turbos? what are you going to turbo 1 and a half cylinders? not gunna happen. 3 turbos....your going to turbo 2 cyls each? waste of money and doesnt have any value except for a "bling" factor.

[2.2 Straight six]

i've seen a pic of a skyline with 3, the reason for it was the lag, using 3 small turbos the engine produced upwards of 800bhp an had pretty much zero lag, all three fed off the same manifold i think.

[SkylineUSA]

I'll be Missouri, show me the unicorn.

[my3rdskyline]

Originally Posted by 2.2 Straight six

i've seen a pic of a skyline with 3, the reason for it was the lag, using 3 small turbos the engine produced upwards of 800bhp an had pretty much zero lag, all three fed off the same manifold i think.

that's funny, i'd like to see that. I wonder what an RB would look like with 6 pulsar turbos on it (^_^)

[tyndago]

Ive seen a Supra with 3 and a 57 Chevy with 8. Just remember more is not always better.

Complexity, plumbing issues. Friction losses. Efficiencies. On average a single turbo is 3% more efficient than a set of twins.....

[Z07]

Originally Posted by 2.2 Straight six

i've seen a pic of a skyline with 3, the reason for it was the lag, using 3 small turbos the engine produced upwards of 800bhp an had pretty much zero lag, all three fed off the same manifold i think.

Given that the RB26 runs a parallel setup and that inertia is proportional to radius squared and flow is proportional to radius cubed. How do you work out that more turbos is better to reduce lag. Using two instead of one can smooth out the spool up and make for a cleaner drive but using a big single generally gives less lag.

The only way to make twin-turbos work to reduce is to opt for a staged sequential setup. One turbo works at low revs, both work at high revs. Or true sequential setup. One small turbo works at low revs, second bigger turbo at high revs. Trying to do this with 3 turbos would be a plumbing catastrophe.

How would you use 4 turbos on a 6 cylinder engine? 1.5 exhaust ports feeding each turbo? 3 turbos is also silly because only 2 cylinders are feeding each turbo which makes for infrequent exhaust pulses and slow spool.

Another 'good' reason to go for more turbos is engine layout. Trying to pipe 2 banks of cylinders (like with V8) into one turbo is difficult. If the Veyron (V16) were to use one turbo per bank (2 total), it would mean plumbing 8 exhaust ports up to each turbine - difficult. Therefore 4 cylinders per turbo were adopted.

One way to reduce lag are by adopting lightweight turbine materials like ceramic. Unfortunately, ceramic is more fragile than steel but operates well at low boost levels. Titanium turbines offer the quick spool of a ceramic with the strength of steel turbines. Magnesium compressors have also been tried but the inertia problem is largely at the turbine side.

Other ways to reduce lag include variable turbine blade and nozzle geometry. The twin-scroll turbines used in jap-spec imprezas are an example of variable nozzle geometry.

[Mr_Powers]

I've seen it on a Subie before, but has anyone ever tried to supercharge a single turbo Skyline? The S/C would solve any lag issue and then a large turbo could be utilized at higher RPMs. What chu think?

[Derby]

Been there done that.

Google on Volkswagen 1.4 TSI or Lancia Delta HF intergrale.

Compressor and turbo.

4 turbo's on a six cil is useless when it is only 2.6 liters to fill. For bigger engines the sequential setup can be usefull.

Derby