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-   -   Pushing The Stock Turbo (https://www.nopistons.com/2nd-generation-specific-17/pushing-stock-turbo-37600/)

1Revvin7 04-22-2004 04:50 PM

Looks like you need a T-1000. 50psi should do it.

j9fd3s 04-22-2004 05:25 PM


Originally Posted by BigTurbo74' date='Apr 22 2004, 11:36 AM
so say i front mounted the stock ic, or got a starion one for example, what about the "pressure drop" that ranzo was talking about?

we just finished the starion core on a stock turbo car, and its fine. if you want with a really huge ic then it might be a problem

BigTurbo74 04-23-2004 12:32 AM


Originally Posted by adamlewis' date='Apr 22 2004, 05:51 AM
Nope. Never ported the wastegate either. Creep was never a problem since boost would always start to bleed anywhere above 5.5~6k. All the stock turbos do it. Only way to fix the bleeding problem is to get a different turbo.

what i want to know is if the ported wastegate can control like 13 psi or if it will still creep if it is ported. and if not, will it continue to build boost above like 15 psi?

Ranzo 04-23-2004 02:58 AM

OK from what I have seen the S5 actuator is just weak. It is supposed to be the same as the s4 just the shape of the rod is different. That being said I have seen boost creep on a S4 with just muffler and air cleaner....I once blew an engine with NO boost controller and A fuel cut defencer. It boosted 1.2kilos and at 6000rpm is **** a seal. https://www.nopistons.com/forums/pub..._DIR#>/sad.png



Unfortunatley there is not much you can do with the stock turbine......I have never seen an aftermarket actuator for a FC turbine, although some might be altered to fit. However on my Hiflo turbines I have a trick......the hi flo turbines have a metal adaptor that the actuator bolts onto, this is to compensate space for the larger compressor side, on this plate I add about 1/2 inch or so of washers to make the spring bind harder and keep the wastegate door closed harder. It has worked flawlessly for me for years and I can boost 14psi all the way to redline. The problem with the stock turbine is that it dosen't have this adaptor........now if you could make one or get ahold of one that would be a different story.



Nissan guys have been using washers for a long time and it is a cheap mans boost controller on a good actuator.



As far as pressure drop ...........I just installed a Trust FMIC in my girls car and there was a very noticable drop in boost response. The car was faster from just before 4000 on but it was not as "peppy" there in the very low RPMs. Playing with the Gain on the VVC and some other adjustments helped tremedously though. A starion intercooler will probably have less pressure drop than say my Trust one but I think the piping on the FC is what adds all the loss. Just read an article in Drift Tengoku magazine and by shortening the piping on a Sylvia they gained torque and it happened at a earlier RPM. Just something to think about.

jahoo88 04-23-2004 03:56 PM

So what Ranzo is saying is that the stock S5 wastegate actuator is too weak and the wastegate flapper gets pushed open by exhaust flow at anything over 5.5k rpm?



I have a home made boost controller on my S5 engine/turbo that is set to 12 psi. I get 12 psi around 2700 rpm in 4th gear but of course it is falls on its face over 5.5 k rpm. Its around 6 psi by 6.5k rpm. i always thought it was just that the stock compressor side was too small and couldnt flow enough to make the boost up high.

j9fd3s 04-23-2004 04:54 PM

hks has an actuator for the fc

Dramon_Killer 04-23-2004 05:36 PM

Yeah my boost completely dies at higher rpms. It'll hit about 11 at 4500 and then by the time i get to 6 its down to 7, 7 rpm sees about 5psi.

Lionheart240 04-24-2004 09:04 PM

The wastegate on my T3/T4 has a stock boost setting of 3 1/2 psi, lol, funny ain't it? :P



How much boost could I push safely on my setup without over-heating the engine too much or just flat out blowing the seals?

1Revvin7 04-24-2004 10:33 PM


Originally Posted by Lionheart240' date='Apr 24 2004, 09:04 PM
The wastegate on my T3/T4 has a stock boost setting of 3 1/2 psi, lol, funny ain't it? :P



How much boost could I push safely on my setup without over-heating the engine too much or just flat out blowing the seals?

Thats hard to say since you don't have the stock turbo. Get on the dyno or get a w/b.

BigTurbo74 04-24-2004 11:03 PM

this thread is so opinionated and digressed it's worthless! can't get a straight answer ****!



drunk


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