s2kslow

Hello all,

Wondering if anyone else has seen or had this issue and might have some insight. I have a BorgWarner EFR 7670 on my ap1. I will list specs below but here is the problem I am running into.
First from everything I have read about this turbo it acts more like a normal turbo then an efr as in it does not come on as quick as most that I hear about. It pulls strong however it comes on more like a normal turbo than what I have read, I thought that was the point of spending the extra on this turbo.
Second it is set at 16lbs right now and while it will spike at 16 it drops back down to 11-12lbs by the top of the gear.
I have changed the waste gate actuator as originally we thought that was the issue.
I have checked all vacuum lines and all couplers for leaks.
I am curious if anyone has heard of this issue on the EFR turbo and if so what they found to be the problem.
Specs: Stock F20
Fullrace mani
B&W EFR 7670 internal wastegate tial wg actuator 10lb spring (4 and 6)
AEM v2
450lph walboro and 1300cc inj with aem flex fuel sensor on e85
3 inch straight pipe exhaust
PLX wideband

Any ideas are welcome

MorngWoodStewie

Where's the boost source coming from?

Are u just on springs?? T bleeder? MBC?

check your tension on the actuator arm. If your preloading the spring it's gonna spike to open up. If it's pre loaded probably why your still seeing higher than ten at top of gear.

s2kslow

Im on the electronic boost controller off of the efr that it came with and set to 16lbs which it goes to but then falls back down to 11lbs. I will recheck the actuator arm and make sure it is tightened down.

MorngWoodStewie

Was this the case at the dyno as well or r u tuning it?

MorngWoodStewie

If it was tuned to 16 best not to call it a spike, sorry miss interpreted ur OP. So problem is ur losing boost after hitting tgt psi, and ur EBC on a IWG with 10lb spring.

3 port or 4 EBC? And can u show a picture how u have the lines setup.

the answers to these questions will help, but I'm not savvy at all with the aem managements. Sum1 should be able to chime in. Might be a duty cycle thing as long as the controller is connected and lines routed right. Have u tried just using the springs to see if it will hold 10? Just for mechanical (boost leak etc) troubleshooting?

MorngWoodStewie

Or is it a standalone EBC? Not tied into ecu?

Mijae007

Good suggestions above. Trying lowering the DC and running it just on wg spring pressure and see if itll hold that pressure all the way to redline. If it does then you can probably assume its an ebc or tuning issue and go from there. I dont think its related to the turbo as if it was that would be a serious design flaw and nobody would purchase that turbo.

s2kslow

It was tuned on 16lbs and was doing the same thing on the dyno. We figured it was the crappy actuator that came with it as they are notoriously bad. On WG pressure it holds 10lbs perfectly no issues. All lines are routed correctly EBC is controlled by the AEM not sure on how many ports will have to look that up. I got some feedback from another friend with a similar setup that it may just be the actuator bar needing to be pre loaded more. I am experimenting with that but have not had a chance to get it out on a test hit yet. And yes sorry not a spike it hits target then backs down. Pretty sure it is not a tuning issue as the tuner is reputable and he also could not figure out why it was dropping off other then possibly the actuator which we have since changed.

MorngWoodStewie

Ic. Much clear'er now.


.... with your above answers I'm still pushing towards your EBC control.

Just look at your solenoid, does it have 3 ports or 4 not sure how to do a 4 but I'm sure mijae does... lol :wink:

To me it's pointing towards your solenoid (capability) or tune (DC)

if u held 10 fine with spring I would of counted the "notorious" actuator out and deemed it good.

i have seen two instances with boosted s2ks on electronic boost control "tuned" by reputable tuners and they were awful! Complete garbage! One couldn't boost past 6k and another would just go complete crazy boosting all over the place (seriously) 8-11-5-15-9 I didn't even think it could go that fast up and down.

A tuner to to me is not a "person" that says GL with your problems come back when u fix it, he should be able to diagnose it and give you direction towards the problem if he can't fix it right then and there.

Not saying this is your case but it comes off that way, your here right? Lol.
:end rant: sorry. .... not sorry if he told you to swap actuator tho lol

your friends advice (pre load) is just a band aid. You will spike and run more boost on current tune if you pre load it more. Just set the tension right.

(on a closed solenoid) if u zero it out (duty cycle) it just WONT route air to the top of the waste gate port and you will run just spring. This is where I can't help on a aem tho. So if you could post a pic of the boost control GUI someone can probably tell you the problem or maybe I can look at it and see some non sense who knows.

Charper732

if you could do a data log and post it, would def help on narrowing down your issue