I turbo charged my N/A motor about a month ago. Aside from the injector leaks and the LIM leaks everything went really well. Being Impatient I was running the car without a boost gauge for a couple weeks. I was running "STOCK" boost IE no controller to the wastegate....so I thought everything was just great. WELL I took it out for a nice drive last weekend and decided to take a video of me ripping it up on some straight aways. At about 7 Grand in 4th I heard a crackling noise that I associated immdiately with predetonation. After checking for external and internal leaks... and noticing the idle of the car and vaccuum to all be steady.... I THINK there was no immediate damage.

Today I finally decided to get the boost gauge in there and see what the **** is going on. in 1st and 2nd the wastegate opens as it should around 6psi or so. Now for the fun stuff.... in 3rd the wastegate will open and then around 5 Grand or so the boost creep begins and goes to 10 psi. In 4th the creep is faster and goes to about 15psi.


Aside fom porting my wastegate... what alternative do I have. Is there a reasonable way to run an external gate. Or what else can I do here.


I want to run RTEK 2.0 and get a boost controller, should I even bother dealing with this problem or should i just get the A/F right and let the wastegate do it own thing???


Thanks for the help

 

Wait, your engine DIDN'T go boom?

 

A boost controller CAN NOT turn down the boost, it can only turn it up. You need to port the wastegate to cure the boost creep, there is no other solution.

 

I know how a wategate works.... I meant is there any readon to decrease the boost by porting, if im going to set it to 13psi with a controller anyways.....

 

13 psi on stock injectors will blow your engine eventually. port the damn wastegate..

 

the injectors are not stock they are 750 cc Secondaries and 550 cc Primaries, and im running rtek 1.7

 

hey man,
did you use the stock n/a intake manifold and a spacer, or a t2 intake?
I am going to be turboing my n/a here shortly, and im going to run the stock intake with the 2.5" spacer, ala aaron cake.
Instead of dealing with notching the frame to be able to run the inferior waste gate, i am going to run a small "h pipe" between the two spacer pieces, and mount an extertnal waste gate down there, welding the stock one shut.

 

Even if you are going to run it at 13 pounds you should still port the wastegate.

 

I ran everything from a t2 except the engine. Id recomend the T2 manifolds...Just make sure you seal the Lower Intake the to the block correctly...TRUST ME ITS A BITCH. As far as using the stock manifolds that seems like a lot more work.

 

External is the way im leaning right now... I did not notch my frame.....

I have about 3 inches between my turbo and the frame.


I saw the thread on exhaust manifolds... Who makes a good manifold for an external wastegate setup, that is a little less crazy than the ones posted?

 

there is a temp solution to boost creep. Its not a good one but one thing you can do is install additional exhaust restriction. You can do this with a thin plate drilled with a 2" hole between 2 of your exhaust clamps. It will make your turbo spool much slower and should get rid of the creep. Having cat converters has the same effect.

 

Im just keeping it under 6 grand in 3rd and 4th until I fix it properly


Cats are about as cool as Natural Aspiration

 

Great quote!!!, I'm stealling it lmao

 

well.. then cats on a naturally aspirated must be really kool!

 

Port your wastegate for sure man... everyone's doing it!

 

I ported my s5 wastegate as much as I possibly can without having to weld washers on..... Even now I still don't think it's enough.

 

Maybe its time to drop an supercharged LS1 in it.

 

with NA compression ratio, and 13lbs of hot air from the stock turbo, the motor wont be very "safe".

 

^ dont be a wuss..

on the bright side... na motors are a dime a dozen..

 

once it blows its getting a rebuild... port job... yada yada yada

Also I have a topmount intercooler and I cut a hole in my N/A hood, and mounted a 40 dollar WRX STi hood scoop my buddy had laying around his basement. So its not "HOT" air its WARM air ok buddy.

Anyonje have a T2 hood??

 

im running the same setup now, last time i had a nice vac leak on the lower intake , haha

 

Yeah I made my own gasket....slathered both sides of it with the best silicon money can buy. and stuck it together... worked mint.

 

Boost creep sucks, it's just not predictable. Before I got my s5 wastegate ported really aggressively my boost in 4th could be like 11 on a hot day and 20 when the temperature gets near freezing

and that 20psi spike resulted in a very loud detonation. luckily enough the motor survived

 

ill sale you a hotside thats already ported...

 

Little FYI, so you know in the future. There's no such thing as predetonation. There's detonation, and preignition. Detonation happens after the spark fires, preignition happens before.