I was curious how quickly the different ball bearing turbos spool on a 7m. I'm planning a complete rebuild for sometime in the next few years, and would like to make power low in the rpm range, but want to make 500+ hp. I've heard that some DSM guys spooled their t60 series bb turbos by 3k rpm, but is this realistic? Any guys out there with a bb that can chime report on this on?
7m Ball bearing spool time?
- Thread starter Neodeuccio
- Start date
MKIIINA said:
I figured I'd switch to a tubular mani, and probably one of the t60 series turbos, but i haven't decided on the details yet. If i remember correctly, which isn't likely, i decided the 60-1 was a bit small, but moving to a t66 would be overkill. I'm not at my comp, so i don't have any of my notes, but that's about all i remember. I was hoping some people might pitch in with their setups and resulting power/spool times.
Ok, I've gotta run. I'll post again tonight or tomorrow when i get back to my comp.
I've managed to hit mid 20 psi range at 60% throttle in 3rd gear at 3800 RPM on my GT35. I think I can get it to spool up even faster than that with better tuning.
Personally, I think that 500rwhp at low RPMs is just going to net you a crapload of wheelspin. I'm not to that point yet and full boost is completely useless through the first 2 gears, 3rd gear you need to be careful with... by 4th you can really let it rip, but by then you're going DAMN FAST.
MKIIINA said:
heh. there's A LOT more to it- compressor + turbine size, then A/R of both housings...
and as we've discussed before, BB doesn't really decrease overall spooltime, just the transition into boost.
I recently talked to a guy who owns a MK4 with a T67DBB (.68A/R). I know he owned a T67 non-BB (.68A/R) before. Anyway, I asked him if he notices a slight difference in spool-up switching from the non-BB to the BB. He said no, there is much more than a slight difference in spool-up.
Spool is such a relative term IMO....for one person it could be how long it takes to get to full boost from 1500rpm, or for another it could be how long it takes to go from 0psi to 30psi at 4500rpm....
IMO, just size your turbo to the power you want to make at XX psi...if you want more power, chances are there will be more lag...just the nature of the beast....
IMO, just size your turbo to the power you want to make at XX psi...if you want more power, chances are there will be more lag...just the nature of the beast....
very true. lag IS overrated and completely subjective. for a long time i've been wanting to compile a list of turbos/mods w/some solid spool characteristics- i.e. go WOT in 5th gear on the road 1500 RPM, record boost level...
Whatever DR J. There's tons of info on the SF dyno-tuning section- for the non-believers. And when you here testimonials from the users of BB turbos backed by dyno graphs time and time again, you start to believe in the advantage. Or you could believe the turbo manufacturers who do not offer a ball-bearing option.
It has been *my* experience, that DBB turbo compared to an "equal" non BB turbo will be quicker to GET to 1psi, but the time to go from 1 psi to 20 psi would be fairly similar between the 2. (just usign these specific #s as an example)
Keep in mind that this has just been MY experience. I do not hold it as Gospel...
Keep in mind that this has just been MY experience. I do not hold it as Gospel...
MRSUPRA said:
i think you're misunderstanding me- there ARE advantages to BB turbos. spool is slightly faster, they're more resistant to abuse, etc. but MY thoughts/experience state that the advantage isn't what it's blown up to be on the 'net....are BB turbos better? yup. is it worth the price? probably not for 98.1% of the people here.