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DIY Turbo Discussion greddy on a 1.8? homebrew kit?

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Old 07-15-2014, 11:25 AM   #61
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The one example with knock is not a very good picture. Knock, before it damages the spark plug, looks like little shinny/sparkly crystals on the plug. Like little diamonds.
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Old 07-15-2014, 12:21 PM   #62
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Like shiny little aluminum flecks from the piston material.
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Old 07-15-2014, 02:19 PM   #63
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The insulator on that plug does not read rich at all. It's hard to say without having the plug in front of me. But those deposits look shiny to me.....and I've never seen shiny ash......even with lead in the fuel.
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Old 07-16-2014, 01:14 AM   #64
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Quote:
Originally Posted by timk View Post
Are the cams expensive? I have flirted with the idea of a VVT head swap but I figure it doesn't buy anything above 4,000 rpm which is where the car spends most of its life anyway.

Pretty substantial difference in power with the fuel allowing extra timing! Wish I had easy access to E85 here!
I agree, 5-7 degrees made a very nice improvement. Also this was with 100 oct regular petrol, not E85. I'd like to try it, but I'm already running around 90% duty cycle with these FIC 650s.

The cams were pretty cheap. Less than $300 usd, and they're not super huge. So if anyone was hoping for "crazy cams", I'm sorry. They're from a company up in Washington stats called Delta Cams and this is their "264" cam for the BP motor. They said that the ramp rate is safe for both hydraulic and solid, but I'll be using hydraulics for it regardless.

Cam specs are
.350 lift (same as BP5 Int or 4W Ex and .024" larger 4W Int)
264 advertised duration
215 @ .050 duration (11 more than 4W Int and 5 more than Ex)
reweld/regrinds

As I said before, they're not huge. And due to certain circumstances I'm running BP4W cams in my MSM so I have more hope that I'll pick up a bit of power. Plus I still need these to pass smog.

I guess I'll check back in here when I get them installed. They're already in my spare head ready to swap over. Just need to find the motivation to pull apart a perfectly good working motor.
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Old 07-16-2014, 01:38 AM   #65
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And thanks everyone for the suggestions on the spark plug. I'm pretty much positive it's not knocking. I can't hear anything with or without my detcans and as sixshooter mentioned, there are no metal specs on the insulator. I've seen that before. Running Rotella T6. I wipe out walmart almost every time I see it when I'm there.

Also keep in mind that these plugs were pulled out pretty much immediately after 10 20+psi WOT pulls with maybe 2 min drive back to our shop.

During my testing, I bumped it up to 25psi with more timing and got it to knock even with the 100 octane. So I understand it's not invincible and possible to hurt it just the same. Thanks Vlad.

So after failing at trying to make more power with more boost and less timing, I turned it back down to 21psi, found where adding timing wasn't adding that much power, and backed it down 2 more degrees.

And I've got some one more step colder plugs (heat range 8) coming in I think tomorrow. NGK (7173) R5672A-8 so I'll let everyone know how those work too. I think I read somewhere that these were stock plugs for s13 or 14s.
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Old 07-16-2014, 01:44 AM   #66
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That's pretty cool.

Lots of testing and feedback is always interesting and helpful to read.

Quote:
So after failing at trying to make more power with more boost and less timing, I turned it back down to 21psi, found where adding timing wasn't adding that much power, and backed it down 2 more degrees.
I think this is another sign that you're choking up, and I don't think its just the cams. While our ancient engines like timing, when running serious MANLY boost levels like that on a setup/turbo that can support the flow, you pick up stupid amounts of power either way.

I know a guy around here with a 35r or something absurd like that, and a very high flowing setup would keep upping the boost and making tons of power no matter what, I think at one point his timing was like 4* or something silly like that, and still made 400+
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Old 07-16-2014, 01:47 AM   #67
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Also here is the log from one of the better pulls. I've massaged the spark map a little since then. Can get a good look at knock and AIT and such.

And let us not all forget that in another 100 miles, I'll be out of 100 oct and back to my 91 tune ;(
Attached Files
File Type: msl 2014-07-12_11.07.30 3rd gr 21 psi 18-20deg 293-266.msl (76.0 KB, 47 views)
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Old 07-16-2014, 02:09 AM   #68
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Thanks Vlad. I think some of your philosophy has passed down to me from all the reading I've done over the past few years.

And if I blow my **** up... Well that'll suck. But should make for more entertaining reading, testing.

"Also while I'm in there and swapping out the head, I've got an ATI super damper and Gates Kevlar belt to help try and hold things together.
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Old 07-16-2014, 08:18 AM   #69
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It almost might make sense on a 91 octane car to retard the intake cam to reduce the dynamic compression ratio so you can run more spark advance even if your cam timing becomes less than optimal.
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Old 07-16-2014, 10:17 AM   #70
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That's going to shift his powerband to the right even more though, won't it?
In which case that sucks.
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Old 07-16-2014, 11:02 AM   #71
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Quote:
Originally Posted by 18psi View Post
That's going to shift his powerband to the right even more though, won't it?
In which case that sucks.
Yes it would, but so will the cams he's getting. In theory those cams depending on how they're timing will already be reducing the dynamic compression ratio.

On that same vane, I'm thinking on a boosted engine running ALLOFIT, there should be significant gains available on a VVT engine by running more cam retard and more spark advance once you're in high boost. I'm not sure anyone has every played around with that, or even setting timing off a tooth to allow even more retard but less advance than the stock setup.
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