3.4L Motor Swap Underway!

[insite]

Originally Posted by Paul

Nice job, could you elaborate on how you moved the pins on the DME harness?

sure. there's a tool that can be used to gently remove a pin from the harness at the DME. after that, it can simply be pushed into another slot.

i don't have the tool, though, so i bought a pin with a segment of wire attached to it. i pushed it into the correct 'new' slot, then clipped the wire & soldered it to the new one.

[xamfed]

I met Insite and went for a ride in his car. I can say this car is insane. It sounds amazing, and is crazy fast.

He took me on some great curvy rodes in Atlanta that I didn't know existed. He has coil-overs and great brakes installed also. Thank God, because we needed them.

Thanks for the ride Kevin, it took me a few hours to calm down.

[insite]

glad you enjoyed it!

Originally Posted by xamfed

I met Insite and went for a ride in his car. I can say this car is insane. It sounds amazing, and is crazy fast.

He took me on some great curvy rodes in Atlanta that I didn't know existed. He has coil-overs and great brakes installed also. Thank God, because we needed them.

Thanks for the ride Kevin, it took me a few hours to calm down.

[mikstew]

Insite, congrats on your build. Looks fantastic, and must feel fantastic to drive.

Just one quick question -

What exactly did you do with your DME? If I recally, yours is 5.2.2, and so is the DME from the '99 carrera you got your engine from. And I know two things that you did:

-Added ONE more wire (well two, with ground) to the boxster ECU to control VarioCam
-Flashed/chipped the ECU to the 3.4 program

Was there anything else you did, and what can you tell me about your flashing/chipping. I mean, what exactly is involved and where'd you get it done?

Thanks!

[insite]

mikstew -

i really just moved one pin at the DME to control the varioram flap. i had the DME programmed to the RoW (euro spec) 3.4L program. that's really it. i used the actuator for the secondary air system (RoW eliminates need for it) to operate the varioram flap. i basically swapped the wire from the secondary air DME pin to the varioram DME pin.

as for the programming itself? you need to take proof of ownership to a dealer & have them print out your immobilization codes. you send your DME, along w/ the codes, to someone who can program it for you (tholyoak).

[insite]

i had the oil from the blown motor analyzed. interesting results available here:

http://986forum.com/forums/boxster-general-discussions/28121-interesting-oil-analysis-blown-motor-post241353.html#post241353

[MikenOH]

One of the guys on the Cayman board had a connecting rod bolt failure--due to an over rev--on a motor that had about 40K. 7300 rpm for 1/2 second--boom.

After the engine was torn down, IIRC, he mentioned that that there is a consensus that these connecting rod bolts will strech over time and that this is really one of the big weak links in the motor for people that do track time and tend to run the motors in in the upper rpm band. His take away was to keep rpm's down under 7K--more in the 6500 range-- since the power drops off above that anyway.

Any thought on this?

[insite]

1) i doubt if a 7300RPM over-rev would cause a rod bolt failure by itself. the rod bolts in the cayman motor are pretty much the same ones in my 3.4L 996 motor, which has a 7300RPM redline. it works out to less than 6% more force (than 7100RMP), which will be inside the design limits for the bolt. risk from over-rev is generally to the TOP END of the motor, not the bottom. the pistons go faster than the valves can retract & a collision occurs.

2) reducing the rev limit will DEFINITELY reduce fatigue and stress inside the motor. force on the rods & rod bolts increases with the SQUARE of RPM's, so the effects become a lot more pronounced as the revs go up. at 10000 RPM, the accelration at the piston is around 250,000 fps/s. at 5000 RPM, you're under 65,000. you've halved the RPM's, but cut the force by 4.

if you drop your observed rev limit from 7100 to, say, 6700, the max forces reduce by about 11%. over time, this can make a difference. personally, i wouldn't bother. as i stated earlier, the functional rev limit is really dictated by the valvetrain.

Originally Posted by MikenOH

One of the guys on the Cayman board had a connecting rod bolt failure--due to an over rev--on a motor that had about 40K. 7300 rpm for 1/2 second--boom.

After the engine was torn down, IIRC, he mentioned that that there is a consensus that these connecting rod bolts will strech over time and that this is really one of the big weak links in the motor for people that do track time and tend to run the motors in in the upper rpm band. His take away was to keep rpm's down under 7K--more in the 6500 range-- since the power drops off above that anyway.

Any thought on this?

[schoir]

Originally Posted by insite

i had the oil from the blown motor analyzed. interesting results available here:

http://986forum.com/forums/showthread.php?p=241353#post241353

What happened to the post with the wrong educated guess on the type of oil that was being analyzed? :dance:

Regards, Maurice.

[insite]

Originally Posted by schoir

What happened to the post with the wrong educated guess on the type of oil that was being analyzed?

still there; it's the last sentence in post #3

[Paul]

Originally Posted by insite

sure. there's a tool that can be used to gently remove a pin from the harness at the DME. after that, it can simply be pushed into another slot.

i don't have the tool, though, so i bought a pin with a segment of wire attached to it. i pushed it into the correct 'new' slot, then clipped the wire & soldered it to the new one.

Thanks, any tricks or guidance on safely opening the plug housing so the pin can be inserted?

Where can we obtain the pins with the wires attached or did someone with correct pin tool remove one from a used harness?

[Jaxonalden]

Any chance you can make a video of the sound a quick ride and post it to YouTube? :dance:

[insite]

Originally Posted by Jaxonalden

Any chance you can make a video of the sound a quick ride and post it to YouTube? :dance:

i'll give it a shot this weekend

[Paul]

Thanks insite for the great info!

[insite]

quick update. car is running great; it's a real rocket. i've ordered an accusump that i'll be installing in a week or two. i finally feel comfortable that i've shaken the car down enough to hit the track. april 11th is the day. i am going to set the car up EXACTLY the same as the day i blew the engine:

same weight, tires, alignment, etc.

the goal is to isolate the time difference ONLY from the engine. also, i'm a little rusty. it's been almost 2yrs since i hit the track. my bogey time is 1:11.6. anything below this is all engine. obviously i'll tape a session or two.

one other note: when i drilled out the exhaust manifold bolts, i meant to post a link to the centering tool i used to get the pilot holes so nice. this thing is AWESOME. it's called the quikcenter and i highly recommend it:

http://www.qbaroo.com/QuikCentercom/

until next time.

[Lobo1186]

how does that product work exactly?

[insite]

Originally Posted by Paul

Thanks, any tricks or guidance on safely opening the plug housing so the pin can be inserted?

sure. this is for the OLDER '99 DME; the newer ones are a little bit different.
1) disconnect the harness from the DME
2) cut the zip tie and open the back of the socket cover
3) use a small screwdriver to remove the weather seal from around the socket
4) remove the phillips screw from the outside of the socket
5) push the far end of the socket down; it will rotate forward & out of the cover
6) pull the socket through the cover

you how have a totally exposed DME connector. the pins are removed / inserted from the back of the plug.

Originally Posted by Paul

Where can we obtain the pins with the wires attached or did someone with correct pin tool remove one from a used harness?

i got mine from a fellow forum member; it had been removed from a used harness. i probably have some if you need one.