bigger turbos are better!

[barkster1971]

http://www.e90post.com/forums/showthread.php?t=401958.

15g is better than 13c.

[baggy798]

Bullsheeet dood! I make 600hp on a 13c at 10 psi!

Actually, there's not much size difference in the comp wheels. I guess it's the larger turbine housing that is doing the majority of good when swapping to a 15g.

[aardvarkash10]

seriously?

Is this what counts for engineering discourse these days?

[Pete940]

Read Stav-tech, his blog confirms the need for adequately sized turbos.
In other words, ditch the td04 series altogether.

[TonyS9]

Well that explains it then, no need for any technical discussion.

[Volvanman]

Well, I have recently changed from a 13c to a 19t, & I can categorically say that the bigger turbo has made the car ridiculously faster. The proof is in the pudding...

[TonyS9]

Did you change anything else (from standard)?

[barkster1971]

upgrades

I had a 13c, then 15g, then 16T , then 19T. The 15g has no lag, together with a V cam that was a nice set up. I prefered the 19T as the power was more progressive. The 13c is good for low down , get you moving sort of power with the T cam. Any more than 10psi leads to problems with the 13c as the bottleneck of the the manifold and small turbine means the heat cracks them and causes the oil to carbon up.
The Swedes would ltao with how small the td04 range is. An Evo tdo5 turbo seems to be perfect for 250-450bhp ( with supporting mods ).
In everyday terms dd way of things when you're not revving and racing the 15g is a lot more practical than a big laggy Holset.

[barkster1971]

bought

Jerry bought my engine off me a few months ago which was a very nice set up for 250-300bhp. It is probably a stage 2-3 set up ( in my car ). Big valve 531 head, b230fk, 3" downpipe, 19T turbo, wasted spark ignition, t5 me7 blue injectors.
I'm building a stage 4 engine which should be about 500-600bhp once I get it running and tuned. That's a hx40 holset turbo at 2 bar boost, 2.5 litre , 16v head on megasquirt mx3 .

[TonyS9]

Slightly modified everything then. As you increase the BHP you need a bigger turbo (in steps) to keep it efficient and make the most of your pressure. Any efficiency that is further away from peak will result in more heat. Charge cooling can also be used in place of a bigger turbo as you need more cooling with more pressure anyway (independant of turbo size).

The original debate stemed from the other thread was that a bigger turbo at standard PSI will give more power in the order of 10bhp, and that Volvo would have been better to do this on the sport model. I hold that it will result in less power. More is not always better.

[Laird Scooby]

Slightly modified everything then. As you increase the BHP you need a bigger turbo (in steps) to keep it efficient and make the most of your pressure. Any efficiency that is further away from peak will result in more heat. Charge cooling can also be used in place of a bigger turbo as you need more cooling with more pressure anyway (independant of turbo size).

The original debate stemed from the other thread was that a bigger turbo at standard PSI will give more power in the order of 10bhp, and that Volvo would have been better to do this on the sport model. I hold that it will result in less power. More is not always better.

If it's running standard PSI/boost pressure then the power won't be altered at all.

You could fit a turbo from the QE II and the engine won't make any more power if the standard boost pressure is retained.
Your car also won't move as the weight of such a big turbo would stop it dead, you might be able to mount the turbo on a trailer but still be lucky to pull away.

The big trouble is that the turbo will be shifting more volume of air than the engine can use so the excess air has to go somewhere. It can't until it reaches the preset boost pressure so will heat up so you'll now have a manifold full of hot air at standard boost pressure. This will almost certainly result in detonation/pre-ignition/pinking/pinging which means less power.

[Joe of Loath]

you might be able to mount the turbo on a trailer but still be lucky to pull away.

Ahem:

[YOUTUBE]VPMBR-imqUk[/YOUTUBE]

[Volvanman]

Slightly modified everything then. As you increase the BHP you need a bigger turbo (in steps) to keep it efficient and make the most of your pressure. Any efficiency that is further away from peak will result in more heat. Charge cooling can also be used in place of a bigger turbo as you need more cooling with more pressure anyway (independant of turbo size).

The original debate stemed from the other thread was that a bigger turbo at standard PSI will give more power in the order of 10bhp, and that Volvo would have been better to do this on the sport model. I hold that it will result in less power. More is not always better.

I disagree. I can say with total conviction that more power is much, much better...

[Laird Scooby]

Nice! I was thinking more along the lines of the turbos on these babies :

https://youtu.be/3xU7Lw9McnM

;) :D

[barkster1971]

truth

As I have upgraded the mitsus I can state from personal experience that 10psi on a 15g is like 14psi on a 13c. Have the people who are guessing at what actual happens experienced it first hand ? All the bs about the engine not being able to "process" the extra flow! You'll be telling me a bigger intercooler is a downgrade next as it leads to more lag etc etc.