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Old May 16, 2017 | 06:07 PM
  #201  
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Car is running. I'm just banging my head against my weak-*** tuning skills at this point. I'm playing with the IAC cranking duty & injector cranking duty to find the sweet spot. It's 58* and pissing rain right now, so not a lot of progress road tuning VE. Yesterday I got my VVT solenoid settings dialed in, so I'll try to do some driving with VVT engaged in the next few days.
Old May 21, 2017 | 10:55 PM
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Originally Posted by Forrest95M
How is the oil pressure when vvt engages?

At temp, idle oil pressure is ~30 PSI. At cruising speed RPM (2-4K RPM) oil pressure is closer to 60 PSI. When VVT engages, oil pressure is closer to ~40 PSI. I'm just easing in to the tuning, so I don't know how it behaves at higher RPM.
Old May 22, 2017 | 10:46 PM
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Originally Posted by wackbards
At temp, idle oil pressure is ~30 PSI. At cruising speed RPM (2-4K RPM) oil pressure is closer to 60 PSI. When VVT engages, oil pressure is closer to ~40 PSI. I'm just easing in to the tuning, so I don't know how it behaves at higher RPM.
I think my valve stem seals went in my 95 head, I might just throw my 03 head on and wait until I can upgrade to ms3 or get vvt tuner.
Any attempt at setting up the vvt table? Is it really as set and forget as people make it out to be?
Old May 23, 2017 | 07:30 PM
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VVT table was not of my creation. I tuned it for my oil control valve duty and signal output. Is it optimal for my build? I couldn't say. I guess you could pay a tuner to dial it in on the dyno or something. I haven't had any drivability issues with it so far.
Old May 24, 2017 | 03:28 AM
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Using the standard DIY VVT map is fine. You might be able to do a little better with time on a dyno, but probably not worth it for the majority of people out there. When cruising around on the interstate your oil pressure gauge may flicker some, if you drop in and out of vvt tuning on around 3500rpms or so. Nothing to worry about with that.
Old May 29, 2017 | 05:22 PM
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I'm just starting to dig into VVT, but I'm struggling. I've fiddled with the oil control valve min/max duty%, and it works OK for a bit, then kinda just flatlines. This is what it looks like when I'm cruising, and VVT goes away. Does this look like bad tuning, or bad mechanical parts?

Old May 30, 2017 | 12:32 AM
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As near as I can tell, this is what happened: I calibrated VVT when CLT was only about 150*F, meaning the oil was not really at operating temp/viscosity. I found that the timing would fully retard at ~ 31% duty, and fully advance at about ~37% duty. I then set the min/max duty values juuust slightly beyond these values (like 30.5 & 38). I think that once I got the oil warmed up sufficiently, 38% duty wasn't enough to build & maintain pressure in the cam.

So first of all, I can see the importance of waiting until the oil is properly warmed up before messing with the VVT. However, I don't feel like I fully understand how the highlighted min/max values should be used. Is it important to have the min/max values very tight up against the value which triggers the cam to advance & retard, or is it better to give a wide min/max range? I've seen threads where people are using 0%/100% as their min/max values. I thought I'd try out 20%/80% and just see how it behaves, but I'd love a break down of how these settings are supposed to work.

Old May 31, 2017 | 10:12 PM
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I've been fighting some cold start problem. Some times it fires right up, and others it won't start at all. I haven't figured out what's going on yet.

Also, it looks like my supertech valve seals are toast.

Old Jun 3, 2017 | 10:09 PM
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I tore into the motor to replace the leaking supertech valve seals. Everything was going fine until...

Nooooo! I managed to knock an intake valve on cylinder 3 into the cylinder.



The valve was sitting upright on the piston, so I took a gamble and decided to pull the intake manifold to see if I could fenagle it back in place. I probably spent an hour & a half with a grabber, but I was finally able to align the valve with the grabber and push the valve back up into the guide by turning the crank. Maybe I should buy a lottery ticket...
Old Jun 4, 2017 | 08:32 AM
  #210  
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You should definitely buy a lottery ticket.

An easy way to keep the valves up while youre servicing it is to line the cylinder youre working on to its TDC, take the schrader valve out of a compression tester hose and pump air into the cylinder. It should force the valves up into the seats.
Old Jun 4, 2017 | 09:28 AM
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I was using an air compressor to keep the valves up, I just got disconbobulated and disconnected the air too early.
Old Jun 12, 2017 | 12:00 AM
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Car seems to be running & starting fine after replacing valve seals. I still don't know what's behind the intermittent start issues.

I put on steering rack spacers this weekend to cut down on bump steer, and it feels good. I also put on a HD deuce roll bar. It's not a popular style on this forum, but it met my requirements for a DD street car (low profile is less likely to cause head strike in a fender bender, and I can still close the top one-handed while driving).
Old Jun 30, 2017 | 08:18 PM
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Old Jul 1, 2017 | 12:37 AM
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Wow, 8 PSI? if so.. holy crap good results

edit: This makes me want to throw my vvt head on asap... but idk?
Old Jul 1, 2017 | 07:24 AM
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Yeah, I don't believe that 8 PSI. Not sure why the dyno reported that. We were horsing around with the EBCS at least in the 165kpa range. I'll plug in later this morning to see where we ended up.
Old Jul 1, 2017 | 07:40 AM
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Originally Posted by wackbards
Yeah, I don't believe that 8 PSI. Not sure why the dyno reported that. We were horsing around with the EBCS at least in the 165kpa range. I'll plug in later this morning to see where we ended up.
165kpa is only a little more then 9psi, so not to far off. Those are some pretty good numbers though. Hopefully you are enjoying it.
Old Jul 1, 2017 | 08:07 AM
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Car is great! Thanks for all the help getting here!

We spent some time tuning VVT and VICS to maximize their contributions. The tuner said he left the spark map somewhat conservative at the peak cyl pressure area, which was in holding with my theme of mechanical empathy. I'm running stock rods and a 1.6 ACT clutch, so my goal was to stay under 225/200.
I don't know much about dynos, but I'd say the graphs above don't capture the low end response accurately. The dyno seemed tricky to load up down low, and it wasn't uncommon to get different numbers pre 3500 from pull to pull without making changes. We were focusing on the upper range on those pulls, so I wouldn't put too much stock into the shape at the lower end. I'll get a log on the street up here for comparison.
Regarding boost levels, I'm​​ thinking it through here, and I plumbed the EBCS reference off of the turbo vac port, and the dyno was measuring boost in the manifold. Probably it's just pressure drop across the intercooler accounting for the difference. *EDIT* but my map sensor is on the intake manifold, so... Dunno. I'll post a log for clarification.

The intercooler worked like a champ. It was about 80F outside, and the dyno said it was 92F in the shop, which I believe. +7F above ambient to an IAT of 99F on a typical pull. Longer pulls with sustained boost would see it go up about +21F to an IAT of 113F. Of course, dyno fans won't be following me around when I drive, so I'm curious to log it and see how it's coping.

Last edited by wackbards; Jul 1, 2017 at 09:10 AM.
Old Jul 1, 2017 | 08:57 AM
  #218  
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Excellent results! Glad to see this turbo on a vvt can produce those results around 8-9psi.
Old Jul 2, 2017 | 10:01 PM
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Swapping in surfboard seats for a little more head protection. We'll see if the SEM vinyl paint holds up. Shure color matched nice.
Old Jul 3, 2017 | 01:50 PM
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Last edited by shuiend; Jul 3, 2017 at 02:05 PM.



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