I snapped a video of the sound I believe to be an exhaust leak. Funny thing is, I don't think it's the manifold and I know it isn't the manifold to turbo. I can't see the telltale black soot or anything around the head, turbo to manifold, or around the o2 housing connection. Going to see if this works:

Here's a link for now, not quite sure how to embed video yet:
https://www.facebook.com/photo.php?v...65792459621832

Edit - the sound is definitely not lifter tick. If I do the old "screwdriver to the ear" trick, the lifters do not get any louder when the sound in the video occurs.

 

Yup I have the 84. I've also heard its a trade off too.

Your ignition timing sounds low after peak load in general. I understand your idea to hold the 3* but are you watching egt? I'm pretty sure I run at least 2 more degrees at that boost level.

 

I'm easing into adding timing. Had a very bad experience in a DSM where I got a little overzealous so I'm taking it little by little as far as that goes.

I looked over another log on a totally different road though, it has the same "tail" at the end of the torque curve, FWIW.

 

Would you be willing to send your rom to me? Wouldn't mind checking out your ramp, and ill send you mine lol

 

You have a PM

 

FWIW, I went back through my logs and found a run from after I bolted on the HTA71 from September that has it spooling to 20 at around 3500 RPM. That was also taken after I did the timing belt which was in July, according to my maintenance spreadsheet so I don't think it's a mechanical timing thing (thank god).

 

Random thought but what about your Mivec? It can alter the spool as well

 

Here are the Mivec maps I've been working with.

 

Just curious, would an O2 dump help lower spool, maybe less backpressure?

 

Somehow that sound in the video is coming from my turbo. Holding a pry bar to my ear, I get no noise if I'm touching the manifold or valve cover but when I touch any part of the turbo, I hear it loud and clear. Going to take the intake off and see if I have any play. I replaced the exhaust manifold gasket and inspected the manifold, no cracks or leaks in any of that stuff.

 

Sorry man I haven't opened that email yet, damaged turbo would def not be up to snuff. I took a 71 out already and my second one is growing weak

 

No worries at all man. Investigating potential turbo trouble is always a double-edged sword. On the one hand, if it's broke, it's upgrade time! On the other, they aren't free and they don't install themselves

So with that said, despite the noise, I didn't feel any shaft play in or out, and just the very slightest wiggle up and down, well within JB tolerances I believe. I also thought something was up because I had an excessive amount of smoke after the manifold gasket install but I think that was just the brake cleaner burning off. I drove it a little and no more smoke, so my two telltale signs are no longer bothering me so, I don't think the turbo is bad. I haven't done a WOT pull since I loaded some MIVEC changes in so I'll see how that goes after my boost leak tester gets here, hopefully tomorrow.

 

I would taper your mivec down as load increases around peak torque/load. I don't believe mivec makes the torque. As pressure increases back pressure does as well which overlap is bad at that point afaik

 

Ok, so more testing, and I think we may be on to something now.

I removed the 3 port from the circuit to see how the car responded to just being on WG spring pressure. I have the turnbuckle on the FP 18 psi gate down as far as it will go without being in hacksaw territory. The result is I can barely build 15 psi with it, even with all that preload. Additionally, spool was no quicker on just the wastegate.

Looks like I'm in the market for a wastegate actuator?

 

I've tried a few different MIVEC attempts and, honestly, none have amounted to anything out of the world as far as difference goes. I loaded John Bradley's GSC S2 map from the MIVEC Tuning thread and I honestly can't see or tell a difference between it, the one I was using for the longest time, and an experimental one I found at the tail end of that thread. I do understand your point though and both the experimental one and JB's maps do just what you're saying.