The Project Pad

dana wrote:What wastegate spring do you have in there? The stockers are pretty damn weak.

I definitely think it should spool a little sooner, seems like your peak power is in the right ball park, but the spool is slow. It seemed like it was taking forever to spool the day we put the boost controller in. I'm looked last night to see if I had any other wastegate springs, but I couldn't find any. I ended up with a 2.2 bar spring in my 90. I was having issues getting it to build boost consistently with a 1.8 bar spring. The 2.2 bar seemed to make it a lot more consistent.

It's a 1.9bar spring, based on the spool pickup I saw from making it adjustable and increasing the pressure I think you're right that this is too weak. The thinking is with a 2.2bar spring I should both pick up spool and let the boost valve work a lot less hard due to higher base pressure which should make it easier to control and more consistent.

Also new log from my morning commute:


And dyno vid #1!
[youtube]https://www.youtube.com/watch?v=ikeICAPIzWc[/youtube]

why not put the bc control crap on hold and just pull the line off the wg and carefully see if you then get normal spool and if you do then work on bc crap?

making something right before you know it is wrong is

Troubleshooting 101 ^^^

pkw wrote:why not put the bc control crap on hold and just pull the line off the wg and carefully see if you then get normal spool and if you do then work on bc crap?

making something right before you know it is wrong is

I did... and spool was pushed back equally. I remapped the boost DC and targets thinking I could get it close enough but no dice. I'll retune those maps from scratch tonight.

loxxrider wrote:Troubleshooting 101 ^^^

See above... I know how to troubleshoot, and either way EBC is not capable of lowering spool when it's still spooling under spring pressure.

I never said you don't know how to troubleshoot, I was just making a general comment. The valve may not be able to lower spool when the spring is keeping the wg all the way closed, but the wastegate will definitely crack open without the boost controller there, slowing spool even at lower boost than your spring pressure is supposed to be for. Of course this depends on how it is set up. Either way though, the difference is pretty marginal. Certainly not enough to cause 5k RPM full boost on an HX35. That should be spooling a full 750-1k sooner (full boost).

loxxrider wrote:I never said you don't know how to troubleshoot, I was just making a general comment. The valve may not be able to lower spool when the spring is keeping the wg all the way closed, but the wastegate will definitely crack open without the boost controller there, slowing spool even at lower boost than your spring pressure is supposed to be for. Of course this depends on how it is set up. Either way though, the difference is pretty marginal. Certainly not enough to cause 5k RPM full boost on an HX35. That should be spooling a full 750-1k sooner (full boost).

You really think I can see 25psi at 4-4250rpm with a 12cm housing? DSM guys see full spool right about there and I didn't (don't) think the 1.8T is capable of spooling it like a 4G63 is.

I think the fact that I dropped 1300rpm in spool is a pretty conclusive indicator that it's a control issue, I'll pressure test the piping tonight and retune the EBC, I think I can get it down below 5k without physically touching the wastegate which honestly doesn't seem too unreasonable for a 1.8l 9.5:1 motor but maybe I'm wrong? If I was running a .70 or .63 obviously I'd be looking for spool a lot sooner.

[youtube]https://www.youtube.com/watch?v=8YBCgoLkdl0[/youtube]

For some reason I thought you were on E85, sorry about that... Haha

Why are you running the 12cm housing? Just to be cheap? I only paid $150 for mine, brand new. I really think it would help you out a bunch.

Well done on the build! Pretty good numbers at least
Might be out of my depths here but I'm curious what diameter IC piping you have gone with. I saw a decrease in spool by using 2" from the turbo to the IC and 2.5" for the test

I can't take the credit for that advice though. Thanks Dave lol

a BEP hot housing should help but an HY35 would also work well on a 1.8 and still get you over 300whp but of course it would give up some flow to the hx35. I think an hx35 with a BEP housing would help spool a lot and keep almost all of the potential of the hx35.

Have you guys actually run a 12 cm housing? The spool is within a few hundred rpm of a 30r with k26 housing. There is no reason in my mind to run anything else.

maybe but a 30r on a 1.8 IS laggy to a lot of people.

hx35 is my favorite cheap turbo for i5. could still be a little laggy for some - it is no k24, but then again it is no k24.



OP, 07k ftw

the 1.8t is a small engine that doesnt flow very well, and the b6 is a heavy awd car......so its going to be laggy with the hx35. Shawn just needs to uncork it so he can reap the benefits of the top end fun!

If it doesn't make boost, you're in the wrong gear

pkw wrote:a BEP hot housing should help but an HY35 would also work well on a 1.8 and still get you over 300whp but of course it would give up some flow to the hx35. I think an hx35 with a BEP housing would help spool a lot and keep almost all of the potential of the hx35.

What about this?

pkw wrote:making something right before you know it is wrong is

I broke another turbo-manifold bolt at some point, not sure exactly when though- I think after the dyno. I've changed up a couple other things, new gaskets and hardware will be here tomorrow so I will get that fixed and start logging again Saturday, hopefully this in addition to the other changes I've made finally get the spool I'm after.

lorge1989 wrote:For some reason I thought you were on E85, sorry about that... Haha

Why are you running the 12cm housing? Just to be cheap? I only paid $150 for mine, brand new. I really think it would help you out a bunch.

I wish I was on E85, there isn't any in Vermont unfortunately.

For the housing, yes to be cheap and because it can perform significantly better than this. I really don't think the spool is a result of the housing, I think there are other things at play right now. I'm not saying it's going to spool at 4k (I don't think it will) but it should be 4000's. Something is definitely not right, and with the manifold-turbo leak I can't be sure of anything I've done in the last week and their effects, but regardless I made big improvements so I haven't given up on this hot side by a long shot

Regardless she still boogies

5th drop to 3rd and up to 6500ish (?) in 4th

[youtube]https://www.youtube.com/watch?v=FBl6lOCwITA[/youtube]

Video is private :(

PRY4SNO wrote:Video is private :(

Fixed!

vt10vt wrote:Regardless she still boogies

5th drop to 3rd and up to 6500ish (?) in 4th

[youtube]http://www.youtube.com/watch?v=FBl6lOCwITA[/youtube]

Tapatalk friendly link without the S in HTTPS

Well obviously one needs to get the spool out of the turbo they have first. I am all for fixing wonky boost control, boost leaks, exhaust leaks, and wonky cam timing. I think that goes without saying.
I was just commenting on the ranking of the different holset combos as far as spool and hp.

Only the end user can decide what spool vs hp they want. I am not trying to tell anyone what their favorite color is.

Okay so I've been fighting a number of issues. First was with the manifold. I cracked a runner off on the same corner of the collector/flange that I keep breaking bolts in. It's been badly abused but hopefully it's good now, I rewelded that runner, went over several others and added braces from the flange back to the head, and class 12.9 bolts all around. All this in addition to my turbo brace hopefully this issue is over with (I've broken 3-4 bolts so far).

Second was with my secondary trigger. Turns out both Marc and I missed that I had the secondary trigger disabled but had the car in seq ignition so I believe my rarely-starts-on-first-sometimes-many-try(ies) issue. For some reason I'm still unsure of, it took me forever to get this working but no trigger errors now and has started first crank every time since I finally seemed to get the right settings. I also managed to kill a starter- this whole issue has been a huge time waster- but at least it's solved.

Full boost is still coming 5100-5300rpm in 3rd. I haven't had a chance to pressure test the intake tract yet, hopefully I'll get to that tonight and report back. I am 100% on my cam+engine timing, if anything I would advance the cam a tooth, but that would only worsen spool so that makes me assume it's right (I hate reading cam timing marks, they always seem to look a half tooth off ).