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I've recently purchased this spring from DEJON Powerhouse. I noticed on the site it says "will not benefit a stock tune". But i'm very forgetful, so i don't want to tune it and forget to put the spring in. So I wanted to put it in now, question is......will it hurt anything if I put it in now???? I mean, i know it won't help, but would it hurt it any if I do put it in with the stock tune???

Also can anyone help on a HOW TO for this spring replacement?? thanks.

:lurk:
 

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from what we've found out, not only will it not benefit without a tune but it will almost definately harm performance with a tune.

the turbo solenoid, controlled by the ecu makes it possible to have finer control of the turbo and keep it spooled longer and at lower loads, the solenoid needs the softer spring so it can do it's work

I say don't put in that spring with or without a tune

here's the info from a gm drive train tech (sodaminsane) on the solenoid and the purpose of a softer spring when a turbo does incorporate our type of solenoid;

In older systems a bypass spring was set for a specific pressure, now we use a vacuum driven solenoid to actuate the canister when we want. The reason for this is that it allows us to fine tune the bypass valve actuation (read delay it).

...

The other "trick" is that because you are using a 2-way solenoid, same as on the wastegate side, you don't need as stiff of a spring. You use compressor out pressure (boost pressure) to keep the valve closed, and then switch it with vacuum (via the solenoid) when you want it to open. This produces a VERY fast response (50ms or less) when you want it.
you'll lose that benefit with a stronger spring
 

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I installed the spring when I still had the stock tune and reverted back to the original after a couple of months. The car seemed to run worse and felt strange between shifts (with the new spring). Changed it back and the car went back to normal. Someone suggested that maybe the spring was causing the car to hold too much boost between shifts... I don't know, but it definitely didn't run well with it installed.
 

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spikester said:
I've been running the Dejon spring for 2 years now, with a Westers tune, and have had no issues at all.
first, we don't know if a tune actually sees the solenoid table, you should ask your respective tuners if they do. if they don't then I guess the stronger spring might help if they tuned for it, but if they could use the solenoid tables you would see quicker response at times using the softer spring

and second, you might not even notice a hit, the turbo just might take a fraction of a second longer to spool, you would contribute that to turbo lag rather then a bad choice in mods

I have had one before and after the westers race tune and have had no ill performance effects that I can tell.

at least you recognize you might not be seeing the damage;

this reminds me of quite a few computer "tweaks", just about every one of them would actually slow a computer down but those performing the tweak would swear their computer "runs smoother"

till of course they benchmarked against a computer without their "tweak" and sure enough their mod cost them performance

some times a performance hit is actually a trade off too, it might quicken on area but slow another.

anyway that's what the solenoid does nd if it's working it needs a softer spring not a stronger one

your tuner might not have the tables to use the solenoid so there is that
 

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I installed the spring when I still had the stock tune and reverted back to the original after a couple of months. The car seemed to run worse and felt strange between shifts (with the new spring). Changed it back and the car went back to normal. Someone suggested that maybe the spring was causing the car to hold too much boost between shifts... I don't know, but it definitely didn't run well with it installed.
now you know the reason, it wasn't because the car held too much boost it's because it didn't hold as much, nor for as long, the solenoid was not functioning as well as it does with the softer spring
 
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