How much Boost should I run? (boostcreep)

PittSpeed Automotive
1

How much Boost should I run?

No need to answer this question…Why?

well, because I dont have a choice.
Its going to be where ever boost creep stops for me.
right now my evo 16g with a 31mm flapper shoots past 18lbs and doesent look like it wants to slow down.

I originally wanted to go with18-19lbs, but now It looks like we’re going with 20+

wish me luck.

huge update also posted on page 2 but for those who want to know NOW read below.
"So after waiting on my new air die grinder and porting bits I finally pull the turbo off.

GUESS WHAT.
there was a small casting imperfection in the MHI 16g that only let the waste gate flapper arm open about 5-6 mm
thats right.
so thats prolly all it was. took 1 min to grind off. could have done it with the turbo still on the car,
but while its off…I have been porting away.
pretty sure this will fix the boost creep." END OF UPDATE

2

what size exhaust do you have? is it creep or spike?

3

3" exhaust from the 2g o2 housing all the way back, also no cat

I’m going to pull the turbine side of the turbo and try to port that out some more, to better match the porting on the o2 housing. according to this tech artice and I’ I’ll let yinz know if it fixes the problem.

Its a creep,
my car is boosting to 11lbs (actuator set) and as I get to 4k+ the boost just keeps rising, and rising.

4

lol looks like an o2 mounted external wastegate is in your future.

5

O2 dump that bitch.

Fixed my creep, anyways.

6

im going to be selling my open o2 dump. Its from xspower. Once i get it off the car $50 bucks takes it if your interested.

7

Do the porting the way the article says to do it.

I had an E3 and it would creep like a mother. Cold weather always makes it worse. The porting helped keep it under control. I could have done more, but I was lazy and didn’t want to take it apart again.

How big are your injectors right now? Are you knocking at 20+?

DO NOT get a bigger flapper, that will just make it hard to hold higher boost if you upgrade later, it’s a total band-aid.

External could work I guess, but it isn’t necessary. You could also make the head flow better, but that’s not exactly a quick/easy fix like the porting.

8

I am interested in going to an Open dump o2,
The only thing is I have a wideband and don’t want it any leaks before the sensor, so as long as it seals up I don’t care about sound issues.

I have 550’s and am not knocking @ 19lbs (I won’t let the car creep past that) BUT I would rather invest in bigger injectors rather than buying an external wastegate set up.

Thanks for the tip on the bigger flapper,
After having creep I was going to kick myself for not getting that done when I bought the turbo. I’ve heard alot of the BAND AID fixes* (ie cat converter, etc.) and thats not what I’m looking for So I’m glad to have Avoided the bigger flapper.

Thanks for the replies my fellow dsm guys! I wasent expecting so many REAL answers on this site! Good to see that were all on the same page.

PS, I have one carbide bit and a airdrill, WHere can I buy more carbide BITS?

9

so the turbo didnt stop creaping and went the 30psi, I had 125% duty cycle on the injectors, and then it knocked turning the headbolts into putty.

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</3

11

I hope nothing else is thrashed besides the hg and headbolts.
did you have arps?

12

that sucks

13

no. no arp’s just stock 1g headbolts

14

get a nice external wastegate.

15

While you have it off, make the head flow more like the E3 already does, and port that Turbine housing wastegate passage properly.

I had a ported evo 3 manifold and full 3" TBE with O2 eliminator with my E316g, and it barely crept past 20 after I ported the WG passage, and I didn’t do that great of a job.

16

If you are going to port the head you should ask Doug to do it.
He’s takes the “just enough” approach… and hell, we pushed 560hp thru his.

Porting a head for something as small as an EIII16g seems, almost pointless. I wouldn’t do much but touch it up. Cams would do alot more for you.

As for the turbo, I’d lay into it pretty heavy and try to knock the wall down. I’d say about twice as much as what you did on CJ’s or more. While you’re there, some time on the o2 housing might help you a good bit too.

If you can get bits, I will take turns laying into that housing until its perfect if you want.

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I’m going to be taking that “while it’s off” approch,

and getting the 272’s replacing the lifters with the 3rd revision. springs and retainers, arp’s and a metal headgasket.
I guess I would need springs too? suggestions?

that should leave me broke.

oh, and port the turbine and o2 housing to keep it away from 30lbs.

18

Run the full BC setup. Cost VS benefit on them is the highest of all choices. And will be good enough if you decide to run a fairly larger turbo later. 50 trim etc.

BC 0100
BC 0101
I run mine unshimmed to well over 9k on these springs with no float issues.

Mitsu MLS
ARP’s

And pray that head isn’t snafu’d to where we have to do new valves.

BC stuff should be ready to rock first week of Jan.
Til then, take it easy. Keep the head on the car, and stay out of the pedal.

19

should I get S.S. valves? Do I need them.

20

I’d rather take a look at the valves that are in there before you go thru the cost of valves/valve job when I know there’s a money crunch.

You’re at the point then where you might as well get a built head.
And just turn yours in as a core.