Hey I'm trying to justify a little bit bigger turbo (GT30BB or 60-1 or full t4) and I'm worried about the spool time. I'm wondering if these have any merit

eight ways to increase spool time:

1. electronic boost controller. By keeping the wastegate from seeing any boost at all until the desired level, You can keep the wastegate closed at lower boost levels, thus reaching max boost faster by not leaking ahead of time.

2. 3" exhaust. By letting the exhaust flow right out, it doesn't build up pressure and slow the flow down and thus slow the turbo down.

3. equal length tubular header. With a good header design, the runners wont be competing with each other. Also by eliminating sharp bends you can eliminate hot spots and get all of the heat through the turbo

4. ball bearing turbo. Since this spins with less resistance it will reach its maximum rpms faster.

5. More displacement. With more air and fuel in each stroke, the amount of gas exiting will increase too.

6. Higher compression. Igniting a mixture under higher pressure will result in more power and thus get the engine to rev faster and get into the spool range sooner.

7. Watercooled turbo. By having the compressor side cooler, there is less heat in the charged air. Now there will be less boost loss after the intercooler.

8. Thermal wrapped header/turbine. Same reasons as 7

do these all sound valid, or are some of them so minimal that there is no real gain ?

edit:sp


[Modified by salt, 10:49 PM 8/18/2002]

 

I thought watercooled turbo does not help decresing intake air temp.

edit:sp




[Modified by dangerzone, 3:32 AM 8/19/2002]

 

i have a problem with #6
even though it may make the turbo spool faster
high compression+boost=broken motor.

 

he didnt say 'high' compression, he said 'higher.' as in higher than 8:1 or 9:1 like many boosted built motors. 'higher' compression would also give better off boost response but requires serious amounts of tuning. gl


david

 

I like number 6 the best.. its all in the tuning.

 

#6 is valid 100%.

 

im not saying its not valid but some people cant afford to have the car professionally tuned and if there running 8+psi on 10.x:1 compression bad ***** gonna happen if its not tuned.

dont get me wrong, i agree with it.
just saying.

 

Regardless of what people can or cannot afford. Higher compression does = more horsepower. So they're technically is no problem with rule #6.

 

#9- Route the BOV upstream of the compressor for quicker spool during shifts.