Spooling too fast??

[canadiandsm11]

So this may be an odd question, but can a turbo spool too quickly?? When I'm driving and get it up to say around 3000rpm, with the boost gauge showing 0 vac/boost, and I give it maybe 40% throttle (that isnt an exact number, but definitely less than 80-->100%), I'll see 10+ psi of boost. It seems like I cant regulate how much boost I can build. Ideally, I'd like to be able to give a certain amount of throttle and see a certain amount of boost, but right now it's more like theres no boost, or alot.
I have a profec b, small16G, 2G manifold, stock 1G o2 housing, 2.5" downpipe and exhaust (no cat)

 

[diablos991]

A small 16G is a fairly quick spooling turbocharger. What you are describing sounds perfectly normal for that turbocharger.

At higher RPMs there is more exhaust flow available to spool the turbocharger. With the small 16G, I am not surprised to see it normally hit full spool before 3k RPMs.

 

[No_Skillz]

As long as you're not overshooting what you've set, there shouldn't be any problem. Also, with a Profec there should be settings that can help change boost characteristics. I don't know the specifics because I don't have one, but their manual should help.

In case you don't have it:
http://www.alamomotorsports.com/greddy/PROFEC_B_SPEC2.pdf

From skimming, I see something on page 5 about boost response and GAIN and START BOOST adjustments.

 

[dontfeedphils]

Thats about when my Big 16G starts to spool, it takes some restraint to keep out of the boost everyday driving since it's so easy to get there.

 

[meliketoball]

At 3k RPM, my t-25 will hit full boost pretty quick haha. Ummm, is the boost going past where you set it? Say you set it @ 14 psi and going to 23 psi?

 

[arash15]

So this may be an odd question, but can a turbo spool too quickly?? When I'm driving and get it up to say around 3000rpm, with the boost gauge showing 0 vac/boost, and I give it maybe 40% throttle (that isnt an exact number, but definitely less than 80-->100%), I'll see 10+ psi of boost. It seems like I cant regulate how much boost I can build. Ideally, I'd like to be able to give a certain amount of throttle and see a certain amount of boost, but right now it's more like theres no boost, or alot.
I have a profec b, small16G, 2G manifold, stock 1G o2 housing, 2.5" downpipe and exhaust (no cat)

I believe this is a good thing. I would create a thread only if the opposite of these symptoms were being experienced. have funn boosting

 

[spawn7037]

Thats about when my Big 16G starts to spool, it takes some restraint to keep out of the boost everyday driving since it's so easy to get there.

Same here with by big 16G. I can control the boost a little if i barely touch the pedal, but whats the point, I did that for one tank of gas to see what mileage I got, turns out I got the same mileage by staying out of boost as I did in boost. Might as well have fun driving while I'm doing it!

 

[neoviper]

I't doesn't say on your profile that you have an aftermarket boost gauge. If you don't than the measurement you're reading may not be that accurate.

But if you have all that and you really are boosting fast, there is no such thing as boosting TOO fast, especially when you're AWD!!!

 

[FlyByNight]

Another problem when a turbo can spool too quickly is when your engine's volumetric efficiency isn't sufficient enough to keep up with the boost pressure. The end result is compressor surge. I would suggest reading the little bit about the 16g at the end of this page:

http://www.ztechz.net/id7.html

Without knowing your max boost pressure and the flow rate through the engine, I cannot tell you whether or not this will be a problem for you, but it is something good to be aware of.

 

[neoviper]

Another problem when a turbo can spool too quickly is when your engine's volumetric efficiency isn't sufficient enough to keep up with the boost pressure. The end result is compressor surge. I would suggest reading the little bit about the 16g at the end of this page:

http://www.ztechz.net/id7.html

Without knowing your max boost pressure and the flow rate through the engine, I cannot tell you whether or not this will be a problem for you, but it is something good to be aware of.

I think I know where you're going with this. Are you talking about an engines ability to flow air at a given RPM?

 

[TunaTalon]

Check your camshaft alignment. Cam alignment may not change the RPM that boost comes on but can change the way the car feels as boost comes up. If your exhaust cam is retarded or the intake cam advanced the boost will come on suddenly.

Please see How to Tune Cam Gears on a 4g63t - My Pro Street for other effects of camshaft adjustments.

 

[hdoerr]

If you do have an aftermarket boost gauge what are using as your boost source. Also check the vaccum lines for cracks this could cause the gauge to act crazy and of course check for boost leaks.

 

[StockSpyder]

Hi guys, noticed some broken links and wanted to update them here :

How to Install 4G63 cams :
My Pro Street | How to Install HKS Camshafts in your 4G63
How to Tune Cam Gears :
My Pro Street | How to Tune Your 4G63 Cam Gears