A 3.4 DOHC Build then... F40 Turbo (Page 9/57)
Joseph Upson MAR 06, 11:54 AM
I understand it pretty well Will and considered similarity in ability between the balancer and the flywheel. The real motivator in re-examining the subject is that you said "End of discussion". You know better than that.

Seriously my thinking and consideration is more from a physics base than occupational so I question for more understanding. Whatever the case, much of the documentation on dualmass flywheels ascribes reduction in tranny gear wear as well as dampening protection from high torque applications (what likely destroyed my F40) as a benefit so you have a lot of correcting to do among the companies stating such.

Whatever you do Fierobsessed make sure you have a good sprung hub on Kevlar disc material as it is noisy on engagement with the tiny spring G6 hub I'm using. I believe I've already mentioned it but the easiest fix for tranny noise without the dualmass flywheel is idle rpm held around 1000.
Will MAR 06, 03:52 PM

quote
Originally posted by Joseph Upson:

I understand it pretty well Will and considered similarity in ability between the balancer and the flywheel. The real motivator in re-examining the subject is that you said "End of discussion". You know better than that.



I knew I'd get pushback on it, but I also know that such devices are employed for noise reduction.

The BMW community doesn't see high failure rates from the S5D-310Z when used with an unsprung disk and a lightweight single mass flywheel.

Your argument seems to be that the dual mass flywheel acts like a harmonic damper in such a way that it reduces peak torque through the drivetrain. This is not the case. A harmonic damper does not reduce peak torque at all.
The only way the flywheel can reduce peak torque through the drivetrain is by slipping. If it only deflects, then a firing impulse will fully deflect it, and peak torque will go through the flywheel to the transmission without being reduced.

The only way available to you to sensibly make a counter argument is to measure the torsional stiffness of the flywheel. Have you done that?
Fierobsessed MAR 08, 06:26 PM
Onward!

Today, I worked on the exhaust. Mainly the downpipe, and the curvy pipe that goes under the engine, the one I call the question mark pipe.
The downpipe to the flex joint, and the flex joint to the 90 degree both had a bit of gap that needed to be filled in. So I changed my steel wire out for stainless wire in the MIG, so these two weld joints got migged, I did the pulse method of welding. The problem with that was that it left little pinholes that I later needed to run the TIG over. Stainless mig is crap. but it'll fill in gaps, where it's not practical to with the TIG. Either way, it's done, and I am satisfied


Then I assembled it.


More parts are on the way. I got a couple more V-bands, one to seperate the question mark pipe from the muffler system, just for convienience. And another to build a Catalytic delete pipe. I don't need it, but if I race, or dyno, It might find its way onto the car...

I bought a 3" muffler, a Borla 40085


I also picked up some more pipe to complete the exhaust, and a couple of exhaust tips. I really wanted to retain the stock tips, but being just 2" pipe inlet, they might have been a bit of a bottle neck. For the new tips, I chose these:



Next week I should be able to assemble the rest of the exhaust.
sleevePAPA MAR 08, 07:38 PM
so um....do any welding on the side?
Fierobsessed MAR 09, 02:58 AM
I honestly don't have a lot of time for side work. You'd be shocked if you knew how few man-hours I've actually put into this project. It's probably about 5-6 hours a week. I just work like crazy when I am on it, get a whole buttload of work done, snap a few pics... ect. And to be honest, it is some of the cleanest work I've ever done!

Once this exhaust stuff is all done, there really isn't a whole heck of a lot of work left. I still have to put together an engine, but that will go very quickly. I still need to make a flywheel, do a bunch of wiring, a bunch of minor things need to be buttoned up. Almost all the money dedicated to this project has been spent, I just need to buy a clutch, and a bunch of small ancillary stuff. It still surprises me how far along this project is, and how little time I have put into it, and for that matter, how much money I HAVE put into it :-)
Will MAR 09, 03:38 PM
Buying stuff and bolting it together is the easy way, but not cheap!
Jncomutt MAR 10, 10:29 AM
That drain line looks tiny.
Fierobsessed MAR 18, 05:56 PM
The oil enter's the GT35R turbo through a .035" restriction hole, the the drain line has a 1/2" ID. So I'm not worried about the drain hose being small at all, probably a bit small for a journal bearing turbo though. I know some gasses must be released through the drain line to the oil pan as well, but it shouldn't be a problem... I hope.

It's time for another update.

Over the last week, while waiting for exhaust parts to show up, I dove deep into the task of building a wire harness. I finally finished the wiring this morning. I can honestly say, I put about a good 30 hours into the harness, perhaps a little more.

If I recall correctly, it started out as a 3.1L Chevy Celebrity harness. I stripped the whole thing down to just what I needed I also had a donor V6 Fiero harness that I got the C500, C203, the bulkhead part, and some of the wiring and connectors from.


This is what the completed harness looks like


This set of connectors is over by the battery, From top to bottom:
Ignition Power feed to ICM
ECM to ICM connection
Crank sensor to ICM
C500 Connector
Constant power connetion


This set of connectors is located near the starter, From top to bottom:
Wideband O2 Sensor controller
Ground lug
Oil Pressure Sensor
Heated O2 sensor
A/C compressor clutch control
Starter solenoid control
Alternator power feed


This set of connectors is located on the rear of the engine block, From top to bottom
Knock sensor
Alternator charge indicator (somewhat hidden in the picture)
Reverse switch
Crank Sensor
Alternator Power
VSS


These 3 connectors are located near where the power steering pump was
Wastegate Control
MAP sensor
Injector harness connection
The 6 injector connections are also shown.


This set of connectors is located under and around the throttle body, From top to bottom:
Ambient intake air IAT
Pre-intercooler IAT
Coolant temperature sensor
Post-intercooler IAT
Throttle Position Sensor
Canister purge Solenoid
Idle Air Control Valve
Exhaust Gas Recirculator


These connectors are located under the drivers side deck grill, from top to bottom:

Electric Cruise control
Fuel pump relay
Cruise control switch interconnection
A/C relay
I may wind up needing to add a third relay to invert the brake signal to operate the cruise correctly


This is the ECM, and the related goods. You can see near the bulkhead passthrough, the Dakota Digital SGI-5 Speed signal converter. This takes the 78 tooth 60,000 PPM VSS signal, and converts it to a 30 tooth 24,000 PPM signal, then feeds it to the ECM. The ECM then converts the 24,000 PPM signal to a 4000 PPM signal. One thing I love about the 1227730 ECM, is that an 87-88 2.5L computer holder works perfectly with it!


You can also see a pigtail sticking out of the harness near the ECM, That contains this simple circuit that buffers the 4000 PPM signal from the ECM for the speedometer. Normally the speedometer is directly connected to a VSS, so this little circuit makes the signal compatible



Some of the stuff I needed for the exhaust started showing up. I got my muffler and my tips! But, I got the wrong radius mandrel bent 3" stainless to feed it. The correct stuff is now on order, but it won't be here till the end of the week.


Stock tips VS new tips


Since I haven't done a fit check in a while It's time to do one.
With the new muffler being 5" in diameter and round, I must make sure everything I've done is working out. And that the muffler will fit where I need it to

Overall Fitment, stll looking great! Wastegate is tightly packed in where I wanted it


This one was a nail biter as I was installing the engine, it was really close!


I tried sticking the muffler in, and found the happy spot for it, Sorry no pictures of that yet, but I got the info I need, the muffler does indeed fit, but not exactly where I expected it to.

I forgot to put up a pic of the Front Mount Heat Exchanger, so here it is:


While I was doing the wire harness, I realized I needed some more connectors to do the job. I found a couple of Fiero's in the pic-a-part and scored a few things, Like the computer holder for the 7730, another 87 4 cyl throttle cable (for my other project...) some A/C hoses, (again for my other project) and I got this!

Recall weatherstrip! in great shape too!

But, on the other end of the spectrum, I saw this horable thing at the pic-a-part:

[This message has been edited by Fierobsessed (edited 03-18-2013).]

Joseph Upson MAR 18, 07:11 PM

quote
Originally posted by Fierobsessed:
This is the ECM, and the related goods. You can see near the bulkhead passthrough, the Dakota Digital SGI-5 Speed signal converter. This takes the 78 tooth 60,000 PPM VSS signal, and converts it to a 30 tooth 24,000 PPM signal, then feeds it to the ECM. The ECM then converts the 24,000 PPM signal to a 4000 PPM signal. One thing I love about the 1227730 ECM, is that an 87-88 2.5L computer holder works perfectly with it!


You can also see a pigtail sticking out of the harness near the ECM, That contains this simple circuit that buffers the 4000 PPM signal from the ECM for the speedometer. Normally the speedometer is directly connected to a VSS, so this little circuit makes the signal compatible





You should need two of those pull-up circuits, one going into the ECM from the SGI and one from the ECM to the odometer. I was told by Dakota after telling them about the combination that I would need a pull-up which is what you displayed, for the signal coming from the the SGI module and when tested without it I did not get a signal to the odometer with the circuit between the ECM and odometer installed alone.

I wrote a thread on it with the specified changes/calibration to run the odometer and the digital cruise if you think it will be helpful. Don't forget to twist the signal wires from the vss sensor.
Fierobsessed MAR 19, 12:18 AM
Hmm... Interesting, I'll check that out. I'm surprised that you needed one between the SGI-5 and the ECM. The SGI-5 has both open collector outputs and A/C outputs, open collector would need a pull-up, A/C should replicate the VSS signal. I'll go check out that thread.
Thanks for the feedback!