Sir-Boost-a-Lot

iTrader: (1)

Once again, very nice work!

MB probably set the compression that low to give a wide margin of error in regards to operating conditions and types of fuels that might get used, Dummy-proof (if there's such a thing).
It's not as low as it looks however, as the cams used by MB to favor a smooth idle in a luxury car yield an early intake valve closing angle. The valve timing is what sets the true compression ratio, and not the piston/chamber volume.

Your car will love the compression!

Denroll

What a great thread. And the best part is not having to wait six months and then asking for updates. Very speedy turnaround!

rockthemullet

Agreed on all points! Imagine the people purchasing these cars brand new... what if they gave their nanny the keys to go pick up the kids and she accidentally loaded it with 87 octane? These motors are not cheap to repair/replace at dealer prices, best thing to do is prevent it if at all possible. When I had everything apart I really should've measured the bowls, piston tops, piston pin location, etc to get a definitive answer on the compression.. buuut I'm fine with a ballpark figure

My hands and the significant other would prefer a longer process but that's just not how I work, haha. It's already taken too long, IMO. I've got the engine back in, trans/converter hooked up, starter, pass. header, plugs/wires, trans cooler lines, alternator, and most of the datalog wiring done. Tonight I'm shooting for driver header, all the under engine wiring, plugs/wires, rebuilt ps pump (should've taken pics when it was apart, I've got an extra if you guys want to see), and belts. I'd really like to get it running this weekend and get datalogs back to Tony at BIP.

PTE

Hello All :
I still drop in 3 times a week to see what is happening ? I see you are just touching on the edge of trying to figure out what your Trapped volume in the combustion chamber is going to be. When I set out to figure what I thought members wanted in a cam design and how many other engines in the m-113 family, I could cover with one set of specs and make it a drop-in part. I my early years & had to deal with motors that would go into hi rpm detonation after a cam change or a intake change . Back in my 2 stroke days I picked up a book THE Basic Design of Two Stroke engines , Written by Gordon P. Blair Professor of Mechanical Engineering, at The Queen's University of Belfast. At that Time I was a Member of SAE and could only get this book , with a computer program that would choke most 286 & early xp computers. I learned a ton about gas flow thru intake & exhaust ports on 2 strokes. Plus & got to meet Gordon thru a work friend , Les Cahoon ,
Blair told me about a Gas flow thru a 4 Stroke head book he just finished and it also had a section on Cam & valve train effect. Great book

http://fourstrokedes********/content/...d-development/
http://www.profblairandassociates.com/RET_Articles.html

Happy reading hope it helps. Patrick T. _PTEngineering

rockthemullet

Thank you, Patrick! I'm in SAE as well, although not very active. The site seems elementary but the books may be the ticket. When I finish my current engine tech selection, I'll have that in my shopping cart

Driver header, exhaust, plugs/wires, ps pump, all oil/coolant/ps lines hooked up, belts, radiator/condenser all installed last night. I need to get the fan in there, and add fluids. I'd really like to turn it over tonight but we'll see what happens I suppose... fluids day is always hit or miss for me

rockthemullet

Car runs. In true MBW fashion, I will now leave the thread and not provide any further updates or performance information.









Just kidding. Car started up on Friday, seemed like it was missing on some cylinders and had garbage throttle response. Realtime data showed the MAP sensor readings were all over the place, boost at idle and whatnot. I pulled the blower and removed the BRAND NEW MAP sensor and replaced it with my old one. Put the blower back on, MAP sensor was reading great but then I had a runaway idle and it would buck like crazy coming off of idle. Turns out I didn't have the IAT sensor in so there was a massive vacuum leak. Now that that's all cleared away, she purrs like a kitten and moves through the rpms great. It was pouring rain today so I didn't get a chance to really stretch legs yet but I'm sideways at quarter throttle just like I was before. With those low load conditions, seeing if there's a difference in boost is just not possible. I expect a slight increase in boost due to the higher restriction of the stock N/A heads.

I'll be datalogging this week, hope to have a slightly more refined tune by the weekend.

stockC43

Congrats

stockC43

I guess you wern't kidding.

Lol. Any updates on this?

rockthemullet

Haha. Datalogged a couple times, getting transmission conductor plate codes so I ordered the parts and it's sitting until I dig in

BI-Performance

Awesome brotha, if you going to need a freshened tune anytime in the near future, Tony will hook you up.

kompressede

Thanks for taking us through the process. Great pictures, and awesome write up. You give inspiration to go ahead and "DIG in"

Glad to see your up and running again.


I recently purchased an SDS, and now I'm looking into a Data Logger.

TruTaing

Congrats! I love how fast this experience has been!

rockthemullet

Well I got the conductor plate done yesterday... That job literally takes less than 1.5hrs from jacking the car up to filling fluids. Had a buddy with an SDS clear the ghost code and I was good to go. Car ran smooth allll day today.

Headed out for some good times with friends...

Then I lifted the driver side cylinder head doing 170 and killed the head gasket... Lol.


Oh well, I'll tear it back down tomorrow. Seemed fine mechanically so we'll see where we stand when the heads come off.

cij911

Amazing work ...Are you logging your car ? I am curious if your car has a fueling problem given two lifted heads on two different motors. What do you think about modifying the fuel system (larger lines, better pumps, looped rail and return) ?

rockthemullet

I'm on ID1000s and twin 340lph pumps. If it's a fueling issue it's in the ecu. I was logging previously but not at the time of the incident, unfortunately :/ If I had, I'd already know the problem, lol. If it was fueling, I would've melted cyl 8.

Just did the math and I was at 178-180 when it happened

EREBUS

This thread rocks. It's like watching your kid grow up in a few weeks!

stockC43

Sucks about the lifted head. How did it do vs the other cars pictured?

Critter

Sorry about the failure, very interesting what you have accomplished in this build. Question, did you use TTY bolts or stud and bolt arrangement or standard steel head bolts for the build. Did you have a remachined head and block surface to allow the gasket to bite into. What are your thoughts on why the head lifted, insufficient torque, gasket make- up, or ?
Pulling that speed for sure the engine is powerful, good luck with the repair.

rockthemullet

I recommend the Zeitronix stuff, so far it's a great bang for the buck. I really want to figure out how to log timing advance through the ZT-2 instead of the OBD2... just need to find the right wire to tap.

I work fast so I don't forget where everything goes

I was basically the camera car last night. The white lambo is a UG 2R, came in second in TX this year. The orange lambo is a UG Stage 3 and the red GTR is a BoostLogic 35R setup. I'm not allowed to talk about the GT500 yet, but it competes very well, lol.

I have ARP head studs and rod bolts, still stretched them. When I tear it down, I'll see exactly how much I stretched the studs, should be interesting. I'll probably be stepping up to the ARP2000 tool steel studs, but I really don't think it should've popped in the first place. I'll be checking the heads for flatness when they come off. Like I said in the beginning, the mileage and condition of this motor is still pretty unknown so I guess it's time to investigate. Gaskets were OEM MB and the torque was according to the ARP procedure. The car was only running for about a week so they didn't need retightened yet. I've been 180+ before, but this time it came up quite a bit quicker.

Hulk

Sorry bro but you will be back. On the zt2 and timing advance it will not work, bassn tried it many years ago and the signal is very bad. If you log only timing you will be fine. Obd is good for only 2 parameters, iat and timing.

rockthemullet

The issue with this is I'm using the ZT-2 without the Dashdaq. If I wanted to record timing via OBD, I would have to log through the Torque app and merge the files (most likely not on the same rate). I have an auxiliary sensor in place for the IATs so I'm too worried about that

Hulk

Damn... And those idiots at drew tech have stopped making the dashdaq

Critter

Put together a 340 Dodge motor years ago all bottom end fasteners were ARP, after initial torques and recheck through the whole bottom end I kept getting more turning of the bolts, after going through the whole thing numerous times (like 10-15) and a few days the bolts finally stabilized and held the torque setting. Did you by chance re-torque the bolts after initially doing so or was it a one time effort. BTW that engine is still running to this day, I often wonder how long it would have run if I just torqued them down once or twice?
Yes head and block surface is very important flat as well as swirl pattern to allow the head gasket to bite.
Personally and I know you would do this anyways is pull the valve cover off the other side and just see where the torque is on the head nuts!

rockthemullet

I had planned on going back through and checking them but felt the motor hadn't had enough heat cycles in it yet. I did go through the motions on the last torque setting (90ftlbs) three times during assembly. I'll be pulling the whole motor to check for damage, and putting in new head gaskets and likely upgrading from the standard ARPs to the tool steel ARP2000s

stockC43

Camera car huh? So, there's video of these shenanigans.

Btw, is the deck thickness any different (thinner) on the n/a heads vs the kompressor heads? Just a thought.