14b internal wastegate

[Jordan Gladman]

i know i've posted this before... but i wanna ask again and see if their are any new opinions on this..

i have my turbo all hooked up and working...  and it runs good til about 6psi... then my fuel setup (dsm fuel pump, vortech 12:1 fmu) kinda maxes out and i run lean... so i bought an s-afc and i plan to install that next weekend... however... even if i am running rich/good... i dont wanna be running 9psi all the time... i have the wastegate hooked right up to the intake plenum and it runs up to9psi... is there anything i can do to the wastegate to make it open at like 4-5psi? is there a spring inside i can hack/add?

[Vlad Busta]

You could try making an adjustable length wastegate arm.  I think that guy with the turbo mini van (Gus) did this and has a How-To page.  

All you have to do is cut the wategate arm in half and thread both ends for a long nut (don't know what it's called).  That way you can lengthen or shorten the over-all length of the wastegate arm.

I think that this may keep the wastegate open a little bit with no boost and open sooner if the wastegate arm is longer.

Try doing a search on CA DSM for an adjustable wastegate arm mod.

Later, Vlad.

[Jordan Gladman]

well... it will be open sooner... but it will still take 9psi to open it the rest of the way... its worth a try... does anyone know the specifics on the wastegate? anyone have a diagram of the inside or something?

[Jordan Gladman]

ahh.. i have an idea..

mount a spring from the wastegate diaphram to the wastegate arm... it will put a pre-load on the spring inside the wastegate.. and the wastegate should open sooner...  

[Ryan Lore]

I really don't think AFC will help you... well it might for fine tuning but I'd guess your poor old pump can't keep up.

You're running a 12:1 reg that means for every 1psi of boost you're asking the pump to deliver an extra 12psi of fuel...

Hmmm 9psi boost x 12psi fuel + base 40ish  = 148psi of fuel.

Not possible.....
Even at 6 psi you're running 112ish, probably the pump limit...


I would look at using a 1:1 reg and AFC and larger injectors and doing it that way, assuming still, your pump can keep up....(as the pressure goes up, volume goes down)

[Jordan Gladman]

the fuel pump is out of a 91 tsi AWD... i was running 450cc injectors but they were just pouring the gas in...  but with the afc, i should be able to put the injectors back in and turn down the duration ... its gonna take a lot of tinkering.. but i hope to get it running good.... i dont think the restriction is the pump or FMU... i think its the computer... its not supplying the duration i need... or so i believe... for the mean time ill get my boost down to like 5psi and i should be ok...

[Jeremy Clarke]

As for the wastegate question you might try getting a 6 psi gate or making your gate open at 6 psi then get a Profec B or similar (or "poor man's profec") so that you can up the boost from inside the car whenever you want.  This way would be much less of a pita than needing to get under the hood every time.

I was going to do this myself but then I realized that all I had to do to keep the boost from hitting 17psi it not to drive at WOT all the time :laugh:

[Jordan Gladman]

i did this... i cut the rod, died it to 6mm... installed a spring, 2 washers and a nut... rewelded it... and it runs just below 5psi... i can adjust to nut back up to 9 if i ever need too  

works perfectly

i have no real need to run higher boost for now.. im on stock internals that are running 9.4:1 compression.. .so i have plenty of that... ill get a boost controller in the future when i build my block

[Travis Merrick]

nice job Jordan, good luck you always seem to amaze me on your DIY jobs  

[Kimyee Lai]

I suggest you double nut it, or you might start creeping back up to 9 psi.

[John Hartman]

Good job Jordan

I do have one ?? tho...  With that wastegate arm mod is it ever fully closed??  My arm was in need of a bending to make it shorter so that it was fully closed.  Before, I was always leaking boost out the gate, and it made for poor throttle response.  Now it hits like a kick in the ass

[Jordan Gladman]

the nut has a little rubber collar on it, so it shouldnt move... i didnt make the arm longer, infact i made it about 1/16' shorter, so it shouldnt be leaking... i still have a little stumble around 6000rpm... but the afc should fix that

[Jeff Armstrong]

Have you done any runs with  a G-Tech yet?

[Jordan Gladman]

Have you done any runs with  a G-Tech yet?

unfortunately not... i cant really go past 5000rpm without detonation... so it wont be all that fast... my s-afc should be here wednesday...  

ill have my car at the deas island meet this sunday if you wanna see it