Spooling - how loud is your turbo?

[BGdude]

Guys, I have the stock T25 and I'm running at about 10 psi, but when I boost, I can here this thing spooling so loud that people are looking around when I drive by them. Are your turbos loud spooling as well? At what RPM does your turbo start to pull? I notice that I have quite a bit of lag at low RPMs and it starts to spool at about 3500. I thought its my engine, but then I drove in my friend's S14 with an S13 black top and same thing...his feels even lazier than mine. Normal to SR's I guess, no?

[Nismo_Freak]

Spool begins at around 2400 RPM, 7 PSI by 2800

It's loud as hell.

[BGdude]

hmm, I wonder why mine boosts so late? Perhaps an S-AFC with some tunning will help. I wouldn't think its the turbo, it goes OK. The timing is at 15 degrees, so I don't know. Any ideas?

[Nismo_Freak]

I have full mods.

[BGdude]

Do you recall before the mods? What helped, tunning, S-AFC? What else do you have in the car? I mean I have HKS Super Dragger exhaust, GReddy DP, 3 inch Test Pipe, HKS turbo extension. Still stock I/C, but I wouldn't think it would effect spooling.....

[Nismo_Freak]

I have a FMIC, 2.25" hotpipe, 02 housing, full 3" catless exhaust, enjuku intake pipe, and an AVC-R.

[mmashburn]

i noticed that with only a greddy turbo elbow and downpipe, mine spooled like crazy and it was loud as hell.... when i put my apexi exhaust on, i couldnt hear the turbo near as good...

[VitaminT]

BGdude what boost controller are you using? Manual, ebc or hks actuator.

NismoFreaks AVC-R probably has a little something to do with the spool time as ebc's usually make boost response a little better.

[Nowhere]

EBC's are gifts from the gods.. The wastegate stays CLOSED until the desired boost is reached, no leaked power.. Insane spooling

[BGdude]

No boost controller, just a little "T" pipe Let me ask you guys, on stock SR's, is it normal for the boost to come late and have that low RPM lag? I mean with my mods, I should see a better turbo response, no? The turbo was inspected before installation and there was no shaft play and it seem fine. Perhaps an S-AFC would help with some tunning? Cheers!

[Nismo_Freak]

NismoFreaks AVC-R probably has a little something to do with the spool time as ebc's usually make boost response a little better.

Yep.

[Nowhere]

Removed Poor Idea lol...

- Nismo_Freak

[NoStickers]

With my t25 it spooled around 2500 and was very loud. I could easily hear it over my gt spec exhaust.

[BGdude]

Removed Poor Idea lol...

- Nismo_Freak

I didn't get that...

[BGdude]

damn...that's a grand before my spools, i don't know what's the deal? do you have a BC?

[NoStickers]

Yes, but even when I didn't have it, it would spool around same time.

[Nowhere]

I didn't get that...

With a source vacuum/pressure signal plumbed DIRECTLY to the wastegate on the turbo, the wastegate will creep open allowing POWER to pass/blead BEFORE the requested max psi is met.

An EBC will keep the wastegate CLOSED (NO power leak) until the boost level has been reached.

A MBC will slow the wastegate opening, it will NEVER operate as well as an EBC..

IF you've got a crappy wastegate/poor setup and want to know if an EBC would work/what it will do for you: a simple test would show you what would happen.

If the signal to the wastegate is REMOVED, it'll act EXACTLY like it's controlled by an EBC (meaning: It will NOT CREEP OPEN). You/driver will have to CAREFULLY monitor the boost as it will NOT be controlled.This will show you the boosting difference between a creeping open wastegate and a EBC CLOSED wastegate (duhh, the EBC will open the wastegate and controll the boost, with the signal removed, there's no control of the turbo, you have to watch your boost VERY carefully (get off FAST when you approach your limit)).

Another view:at like 5 psi ish guess/example, the wastegate is open a little when no EBC is present.

Plumbing the wastegate accuator directly to the manifold/source/signal with NO means of boost control (wastegate CLOSED until desired pressure has been met) will result in slower spooling and less power.

Does that make sence?

[srdrps13]

my t25 was making all sorts of sweet noises lol.. loud as hell but i later found out the manifold and turbo was coming apart causing it to be extremely loud, i dont know check that out ?

[turbo_lover]

i noticed that with only a greddy turbo elbow and downpipe, mine spooled like crazy and it was loud as hell.... when i put my apexi exhaust on, i couldnt hear the turbo near as good...

Right. exhaust quiets a turbo car good. With out a DP & Exhaust, it is louder and faster spooling.

[Neil]

how does the turbo get quieter with the exhaust? or do you simply mean the exhaust was so loud it drowned out the itake sound

[NiSmo240luvR]

when i first got my sr i had stock exhaust and i could hear my turbo spooling loud as hell. once i put my exhaust on it kind of drowned out the turbo spooling but you could still hear it, obviously. now last week i put on my one piece 3"dp/tp and the turbo spools sooo much louder now.