Turbo spool-up delay caused by Profec Type S?
 

I just installed a brand new set BNR twins in NS configuration. When the turbos arrived the actuator had one outlet welded up which eliminated the use of my PFC as a boost controller. So, initially it was installed with only a stock rubber hose (no pill) between the turbo pressure outlet and the actuator.

The spool response was quite good. I had 7 psi (spring rate) by 3800 and I could get 5-6 psi in 5th gear by 2800.

Then, I installed a Profec Type S. It controls the boost just fine but, I lost about 400-500 RPM in spooling. Even with the Profec OFF I get 7 psi around 4200-4300 and the boost builds definitely slower. With the Profec turned ON 10 psi comes up around 4300 but, the boost really starts to come on hard in the high 4K range. Up to that point it comes-on kind of "soft".

I tried to keep the rubber hoses to minimum but, they're probably still nearly 20" long vs the 3-4" length of the stock hose. I needed that much to get the Profec away from the heat source of the turbos. Could that be the problem?

Albert

Have you played with the GAIN setting yet?

Tyler

Yes, I went all over with the GAIN from minimum to maximum. It makes a difference but, nowhere near enough to give me back the 4-500 RPM that was lost to the controller. The boost just does not build as crisply with the Profec as it did with either the PFC before or with just the factory hose (7psi).

I purchased the extra large waste gate porting with the BNR and still got boost creep when using a resonated midpipe! So, back to running various Supertrapp configurations. Have just proven that Supertrapp's claim where 20 plates equal the free flow performance of a 3" free flow exhaust is bogus. I tried 20 plates and ran a 70-130 MPH acceleration in 9.3 sec at 14 psi boost. With the back plate off it was 8.45 seconds. Sizable difference!

Albert

isnt the pfc boost controller not accuret?

The PFC worked just fine with my stock turbos. I considered changing the actuators so that I could still use the PFC with the BNRs but, there are two potential problems. The BNR requires a longer actuator arm, given the extra length of the BNR assembly when compared to stock turbos. The second issue is that the PFC seem to be limited in boost capacity so, I figured that the Profec would be a good solution.

Albert

I'm stumped Albert, my Profec has spooled as quickly as stock (if not faster) since day one. Perhaps you have some issue with the install or your solenoid is not operating properly.

I guess it is one more thing to figure out. The installation is so straight forward that it would be difficult to mess it up - and I've already triple checked it. A bad solenoid is a chance, although, the boost is delayed even as the Profec is turned OFF. The solenoid may not be opening or closing entirely which could slow the response. I will try to bypass the solenoid with a straight splice-connctor to make sure. If, at that point, I still have the delay than it must be the extra hose length.

The electrical connectors are foolproof, you can only connect each set of wires into the connectors that they fit.

Hmmmm.... after writing all that above AND reading the manual one more time, I came across an "Important" information which states that the little filter (inline with the turbo boost to the Profec control unit) must be installed in the "correct" position. I saw that before the install but could not find any reference as to what position was "correct" I could blow air through the filter just as easy from either direction.

Anyways, I got a magnifier out and looked at the instructin manual and was able to identify the outline of the filter in the "correct" direction. Went out and checked on the car and I installed it backwards. Sure hope that is the problem but, would find it hard to explain why, given the apparent bi-directionality of the filter element. Then again, they would not warn you if it was not important... I guess?

Will try the car tomorrow. Would not want to scare the deer in my area this late at night. It is sucidal to drive fast around here anytime after dusk. Deers are all over the roads.

Thanks for the advice, which made me recheck the intall once again...

Albert

Thanks for not being offended by my suggestion, I know you know what you're doing around cars. :) Sometimes though, the best of us can miss some little thing.

Does the Type-S still have the jumpers on the back that need to be set correctly? Just brainstorming, I can't see how that extra 20" of hose can really increase the lag that much.

Tyler

No jumpers to set on the Type S. Simple, keyed electrical connections. It is as close to a foolproof installation as one gets... which make me look real bad for missing the filter direction. I'm cautiosly optimistic but, still can't figure out the difference in the directionality as I blew air through it prior to the installation and again, just now, as I reversed direction, and detected no noticable resistance in either direction.

Albert

Have you removed ALL the plastic plugs from the solenoid?

Thanks for the suggestion but, yes, I removed all the plugs.

Changing the filter direction did not do anything either. Still about 400 RPM late on the spooling. I now get 10+ psi @4200 vs 3800 before the Profec install. I can live with it fine as I never floor the car below 4500 RPM to begin with. Most of the real power curve is above 4500. Just wondering what caused that shift in the turbo spooling time?

Albert