Borg Warner S362

[Rich76_911s]

I've been putting some miles on my 930, almost at the 500-mile mark and need to do the first oil change, valve adjustment, and head stud check after break-in of the engine.

The engine is running great and I've been getting some boost into it. I currently have it limited to 0.3 Bar. (Yeah I'm over cautious.)

But having read through this thread several times: turbo swap: BW S362

I gotta say my turbo (BW-s362) is not acting in the same manner. I get no boost whatsoever in first gear, and it doesn't seem to come on until later than the old 3ldz.

I'm thinking that maybe I choose the wrong hotside housing. Turbine Housing

I picked this housing because it was the only housing for the 300 series that was T3, divided, and the 14cm translates into about a 0.82 A/R. Which all seemed pretty appropriate to our cars. I was shooting for a smaller A/R to get earlier boost onset.

I did some research to find that 14cm conversion, but I don't think I did enough homework. It seems that you cannot accurately convert a 14cm to A/R. So I think I may have too large of a housing on the hot side.

Basic rundown of my engine:
3.5L 7.5:1
CIS
SC-Cams
Single plug
Garrett Long Neck Intercooler
fabspeed kinda sorta not really divided headers
zork tube

You guys have any advice on whether or not I choose the wrong housing, and if so, what I should change it to?

Maybe nextime I take the car out I'll shoot a video with some pulls to show how it is performing.

[quattrorunner]

Watching. I didn't know they made a t3

[Rich76_911s]

Originally Posted by quattrorunner

Watching. I didn't know they made a t3

AGP has a few T3 housings for the S362:

.63 A/R T3 open 3” V Band
.82 A/R T3 open 3” V Band
1.25 T3 divided 3” V Band
14cm T3 divided HX40 V Band

[Tippy]

An 0.82 AR on a T3 is fairly small for BW's.

I have a 0.91 AR T4 (73mm) on my S366, and it spools better than my 60-1 0.84 AR T4 P trim (64mm) turbo I had.

With that said, if my enrichment is lean (when goosing throttle), it's a little laggy. If I get 10's (AFR's) on the stomp, she starts to light up nicely.

Sure you don't have a boost leak?!

[Rich76_911s]

Hey Tippy,

I don't think I have a boost leak, but I'll give it a once over. Thanks for the suggestion.

[jpnovak]

at 0.3bar limit I doubt you are driving hard enough to generate enough exhaust pressure to really spin the turbo.

Crank it up and see what happens.

[dos531]

How are you limiting it to .3 bar? Wastegate spring? If so, a spring that weak is going to blow open really early and slow down spool significantly.

[Rich76_911s]

So yes, I have a very light spring in the wastegate that came from UWON who used it to turbocharge his 3.2L N/A engine.

Stupid question, I have a manual boost controller. Is it bad to crank the MBC up to 0.8 Bar and hit a spring in the wastegate that is built for 0.3 bar?

Alternatively, I can put the original wastegate spring back in the wastegate as well.

[356911930]

Rich,

Your 0.3 will only see 0.3 bar when you crank up the MBC to 0.8 bar so no damage or problem should arise. This is what they were made to do.

Let us know the results.

Rahl

[willtel]

Originally Posted by jpnovak

Crank it up and see what happens.

More boost is always the answer.

[xbmwguy]

I don’t believe you will see .8 while using a .3 spring. You will be bleeding off boost pressure way before your desired .8. Put a .8 spring in and show some restraint

[Tippy]

Deleted

[lite75]

not any pressure being generated to push down the diaphragm, you need a bigger spring..

[Rich76_911s]

Good news is the spring is a very easy change. All I have to do is find the box with the stock spring.

I'll probably pull the wastegate when I do the valve adjustment.

I wouldn't have thought a spring would impact lag, but clearly I need to do more work on this subject.

[dos531]

Originally Posted by Rich76_911s

Good news is the spring is a very easy change. All I have to do is find the box with the stock spring.

I'll probably pull the wastegate when I do the valve adjustment.

I wouldn't have thought a spring would impact lag, but clearly I need to do more work on this subject.

You can use the mbc and see if it hits your desired boost. The wastegate is not an on/off switch, so even if it is a 0.3 bar spring, it will start opening before that.

[xbmwguy]

Usually you can only achieve double what the spring value is while using an ebc or ebc. .8 can be used to see 1.5 although I use a 1.0 spring

[kenikh]

Gotta up that boost. At 7.5:1 with CIS, you can push 1 BAR without issue, with non aggressive timing. I was limiting to .5 BAR and it ended up being a mistake, with results similar to yours...and that was with a K27.

Sent from my Nexus 6P using Tapatalk

[Bucketlist]

Am I correct on this?
My mbc limits the boost signal to the lower port of my wastegate which (mostly) replaces the spring and allows boost to the limit of the turbo (danger! danger!). If I back off the mbc all the way the spring will control boost. I keep mine at about .9 max with a .6 spring. There is no effect on the vent side unless yours is plumbed differently.

[GJF]

You are correct. It is the MBC (regulator) that has limits. There are MBC that are only good for 10,25 and 50psi differential above the spring value. Meaning you can only go above the installed spring setting depending on the rating of a given MBC. This also applies to integrated EBC in ECU's or stand alone EBC's. The valves used with either or have ratings for amount of boost that each specific valve can control. It's the actual spring inside the MBC or EBC control valve that dictates the ability of each valve.