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ForcedInduction
01-07-2007, 08:57 PM
Pictures-
1: Start of the project. KKK K26 turbo.
2: EGT probe in the exhaust manifold.
3: Stock turbo drain tube after it's been cut. Air filter oil drain visible behind it.
4: VNT mounted.

ForcedInduction
01-07-2007, 09:03 PM
1: Second view of the turbo
2: Finished drain line.
3: Actuator.
4: Finished.

Videos: (It sounds much better in person than on my cheapo camera.)
Quick tour around the car. (http://www.youtube.com/watch?v=L-qW-PpPYy0) Notice the actuator moving and the intake tube expanding when I revv it.
Some easy driving. Barely 1/3 throttle application. (http://www.youtube.com/watch?v=cxAxmbDKzNY)
YouTube seems to not like my full output video. I'll link it when it's done.
Just playing around with it a bit. (http://www.youtube.com/watch?v=19BjRqvnAi0)

Notes-

I cut a bead on the stock intake manifold to keep the tube in place.
The turbo works great as a warmup exhaust restriction (I can see this becoming a problem in the summer).
There is about 2psi of exhaust pressure and just a *hair* off the peg of boost at idle.
There is almost no boost drop between shifts.
EGT's still run in the same ranges. I can easily pass 1250*f.
Decelerating from highway speeds maintains about 6 psi of boost all the way down to 30mph in 4th gear.
The turbo seems hover in the 10psi boost and 10psi exhaust pressure most of the time I'm moving under load.
Boost stays around 8psi : 10psi cruising the highway between 55-75mph.
Max boost is about 11psi below 3500rpm and peaks at 14psi by 4500rpm.
Exhaust pressure at 14psi boost is 20psi. 5psi less than the KKK K26 turbo.
Exhaust pressure can pass 30psi on a hard takeoff and free (no-load) revving.

I will concede that the GT22V is too small for an OM617. EGT's are still excessive at full load.

My main concern is the high initial exhaust pressures (Pegs my 30psi exhaust gauge). I'm worried that it can float the exhaust valves. I don't know at what psi the exhaust valves will lift off their seats.

bgkast
01-08-2007, 01:09 AM
Isn't there something you can do to limit the boost?

You could reach over 1200 degrees with the KKK and no IP modifications? I can hardly pass 1000 with my set up, and that was before I intercooled.

Speaking on intercooling maybe that should be next. ;D

ForcedInduction
01-08-2007, 09:54 AM
Speaking on intercooling maybe that should be next. ;D

Nothing I can do about the max boost right now. The vanes are all the way open at 10psi. The only thing I could do is install an external wastegate.

Yes, 1200 was easy to reach with the K26 turbo as well. I have a feeling it's because of my injection timing. I'm going to redo it and advance it to 26*BTDC next week.

An intercooler is next. However, it's not high on my priorities list right now. I need to concentrate on getting that replacement engine and prepping it to swap out my current engine.

ForcedInduction
02-05-2007, 04:17 AM
Now that YouTube has FINALLY :mad: got my video active, here it is: http://www.youtube.com/watch?v=uLgEnnQaR54 I do a bit of revving to get the turbo going and I get to 60 at the top of 3rd gear.

Nothing amazing, it's only about 1/2 second better overall. The video I have is 13.6 seconds 0-60 and the best I can get is 13.2seconds. The roads are still cold/wet so I kept spinning the right rear tire every time I tried to do a serious balls-to-the-wall run.

Bandimere Speedway will not be dong it's CSP (Open/Test-N-Tune) races until starting after May-02-2007 (LINK) (http://www.bandimere.com/events/event_detail.php?eventID=175). Sometime after that I'll see about getting an official 1/4mile time slip.

pawoSD
02-05-2007, 04:42 AM
I was looking at all your videos on there and noticed the one with the mean green starter....is your car equipped with one? Would you recommend them? At least one of our cars is going to need a starter within the next year or so...(including my car probably :o ) so I am curious if they are worth the extra $110....primarily for any advantages in crank speed/extended crank time in the freezing cold......

-7.5F here right now!!! :eek: :eek: :dizzy2:

ForcedInduction
02-05-2007, 04:48 AM
I don't personally have one. That video is from a fellow member here, I forget the screen name.

I want one, but my stock starter is working fine so I can't justify spending $300 on one right now.

Kynetx
02-06-2007, 03:17 PM
Dead sexy. Why didn't you install an intercooler though? Just curious.

winmutt
02-06-2007, 03:55 PM
how far have you taken it into 3rd? I can get up to 70's or so in 3rd.

Mercury
02-06-2007, 08:00 PM
I will concede that the GT22V is too small for an OM617. EGT's are still excessive at full load.

Too small means too restrictive at the exhaust?, thus too much back pressure, and higher EGT (WAG on my part) ?

Now, educate me, what influenced your decision to use the GT22V? What would have been a better choice with your "too small" comment in mind?

thanks.

1985 300SD Sady
02-06-2007, 08:22 PM
I was looking at all your videos on there and noticed the one with the mean green starter....is your car equipped with one? Would you recommend them? At least one of our cars is going to need a starter within the next year or so...(including my car probably :o ) so I am curious if they are worth the extra $110....primarily for any advantages in crank speed/extended crank time in the freezing cold......

-7.5F here right now!!! :eek: :eek: :dizzy2:

That video is breckman99's.

Take a look at his thread on it here > http://www.mercedesshop.com/shopforum/showthread.php?t=146718&highlight=green+starter

From what I understand, he was happy with the starter, but the customer service was not very good.

1985300d
02-06-2007, 08:41 PM
i can get 80 km/h in first at 4500 lol:silly:

ForcedInduction
02-06-2007, 11:15 PM
I say it's too small because I can get ~25psi of backpressure for 13psi of boost. In an ideal world, that number would be close to or under 20psi.

The biggest VNT is the GT2559V before you jump up to the huge GT37V.

"Dead sexy. Why didn't you install an intercooler though? Just curious.

I will, soon.....
http://www.mercedesshop.com/shopforum/showthread.php?t=178016&highlight=air-air

ConnClark
02-07-2007, 03:03 AM
I say it's too small because I can get ~25psi of backpressure for 13psi of boost. In an ideal world, that number would be close to or under 20psi.

25 psi to get 13 psi is actually not to bad.

total efficiency = compressor eff x turbine eff.

For example take a turbine thats 70% efficient and a compressor thats 76% efficient you get a conversion constant of ( 0.7 x 0.76 ) or about 53.2%

25psi x .532 = 13.3psi


there are more accurate formulas but this is a good approximation.

ferdz
08-15-2008, 02:21 PM
Pictures-
1: Start of the project. KKK K26 turbo.
2: EGT probe in the exhaust manifold.
3: Stock turbo drain tube after it's been cut. Air filter oil drain visible behind it.
4: VNT mounted.

sir where connect this hose in this pic. thanks sir.

ForcedInduction
08-15-2008, 10:18 PM
The atmosphere, about 6" above the road.

jt20
10-29-2008, 03:03 AM
FI, Do you still feel this turbo app. is too small, or have other adjustments compensated for the backpressure? You said you can cruise w/ zero boost recently.

ForcedInduction
10-29-2008, 06:17 AM
Is good for a stock or slightly modified 617 but I wouldn't trust it above 20psi, it already whistles pretty good at 13psi.