[Neanderthal Racing]

Originally Posted by 91TB78

Bruce, is the crap built up on the combustion chambers a result of the AP?? I don't think I've ever seen an engine look so nasty before.
Todd

the license plate holder says "cobb tuned"

[WolfPlayer]

9.8-10.2 AFRs with > 100% IDC in many places. Definitely not acceptable. However, it is extremely important to note here that Cobb's maps are leaner than the stock maps! IMHO, what you are seeing could absolutely have been worse had you not been running Cobb's maps. The stock maps are definitely richer ... I can post pictures of each if you would like so as to offer proof of that statement.

AFTER tuning I put the AFR around 11:1 and had 90% IDCs.

t

[Singletrack]

Originally Posted by WolfPlayer

9.8-10.2 AFRs with > 100% IDC in many places. Definitely not acceptable. However, it is extremely important to note here that Cobb's maps are leaner than the stock maps! IMHO, what you are seeing could absolutely have been worse had you not been running Cobb's maps. The stock maps are definitely richer ... I can post pictures of each if you would like so as to offer proof of that statement.

AFTER tuning I put the AFR around 11:1 and had 90% IDCs.

t

That graph is a little difficult to read in comparison from what you might receive from a tuner for an AF ratio. i.e. A single dyno pull showing AF ratio from like 1500RPM to redline. Have anything like that?

In the AF graphs I've seen (mainly 04s, maybe all 04s) the car does NOT run that rich. Usually starts at 14.5:1 or so and tapers to 10.2:1 or so. 9.8:1 seems ridiculously rich. Regardless, what your graph doesn't show is the AF ratio over the entire powerband.

[wdb]

Originally Posted by BruceChapman

words cannot express my disgust at the condition of my combustion chambers including the heads, valves and pistons.

so, you think you are running rich with accessport? i used to joke about what my tailpipe looked like.

Hmmm. It's been a while since I pulled heads off a car, but for 40,000 miles that engine looks pretty darn clean. Hardly any buildup on the pistons or valves at all.

As for the black stuff -- like I said, I haven't pulled heads in a few years, so my knowledge is a bit rusty, but it looks like there isn't very much of it at all. One piston has a spot where you wiped it right down to a clean piston top. I wonder if that amount could build up by starting up from cold and idling for a few minutes, then pulling into the garage.

[WolfPlayer]

Originally Posted by Singletrack

That graph is a little difficult to read in comparison from what you might receive from a tuner for an AF ratio. i.e. A single dyno pull showing AF ratio from like 1500RPM to redline. Have anything like that?

In the AF graphs I've seen (mainly 04s, maybe all 04s) the car does NOT run that rich. Usually starts at 14.5:1 or so and tapers to 10.2:1 or so. 9.8:1 seems ridiculously rich. Regardless, what your graph doesn't show is the AF ratio over the entire powerband.

First of all, it depends on where the wideband is placed. If you are on a dyno and they stick the wideband up your tailpipe then forget about it ... it is going to read leaner if you have cats in the system. You can't trust that value if the wideband is behind the cats. Want some proof? Sure. Here is a dynojet dyno with wideband on my stock car. The wideband was placed in the tailpipe behind the factory cats. Lower than 10:1 AFR and this was AFTER 2 cats. Stock fueling on the '05 is richie rich beyond compare. At least Cobb does lean it out some!

http://www.bescaredracing.com/sti/dyno/stock/hp_afr.JPG

As far as the graph ... I didn't do a run with the intention of graphing something for general consumption. I had a WOT run on my laptop and decided to post it so that others could see. If my intent was to show AFR over the powerband then I would have done what you suggested and started in 4th gear. But, alas, this is an afterthought.

t

[Neanderthal Racing]

i'm ok with letting cobb off the hook and moving on.

we cleaned up the heads.
ricky port-matched the intake and exhaust manifold ports.

i decided to have the valves lapped and i'm replacing the stock springs and retainers with a crowler spring/titanium retainer kit which be sent tomorrow am from dpr in toledo. it's going to slow down the build but i can't help myself.

i'll be posting pics tomorrow.

[Neanderthal Racing]

i just posted this on nasioc

this is a copy of a response i pm'd to a friend about the same pics:
the cylinders caused a lot of controversy on nasioc with most people thinking i blamed cobb unfairly and attributing the crud to oil. theyre probably right, given the qt per 2000 miles i was using. some people thought they looked normal.

i think two things are responsible:

- i didn't seal the rings aggressively enough. i didn't quite stick to the factory break-in but i didn't deliberately load them hard either. i won't make that mistake this time. 10 minutes after it starts, i'm taking it straight to the ny thruway with a couple spotters then return and change the oil.

- the dealer convinced me to switch to synthetic at 1200 miles. i never really believed the avoidsyntheticduringbreakin theory but i do now.

that's a close to admitting i might have been wrr...wrrrr...wrong as i get. that's a lot closer than i've seen some of the people who hyperventilated the hardest on this one ever get.

btw, i tried to change the threat title to "what my combustion chamber looks like" and drop the "with ap" off the title. if one of the moderators would like to help correct that i'd be your humble **** head... forever or until the project is done, whichever comes first.

[Neanderthal Racing]

day 18 - yeah...it's still hanging

the local subie dealer gave us an incomplete gasket set and basically screwed things up reassembling the motor for the next couple days. we're finding other things to do instead:

pics

in order:

- an unported intake port
- comparison of intake ports pre and post port matched
- unported exhaust port
- ported exhaust port
- the swept aluminum debris after port matching just one head. that's a size 12 foot for perspective.

[Neanderthal Racing]

more day 18 pics

in order:

- hydra in the floorwell, 90% installed.
- defi link unit in cup holder space. it will be dressed up later.
- seibon pd cf hood scoop just screwed in place for these pics. i'm painting the screens wrb.
- scoop approximating the driver view.

[wdb]

Dang, it's starting to look like "Breathe the first fire of life" day is going to be during my vacation and/or the full week of training following it. I may miss it.