starting my twin plug conversation

[T77911S]

Got my COPs today.
12 denso plugs for under 400!!!
Got my connectors.
I have my cam sync, crank sensor, knock sensors, head temp sensor and air temp sensor all installed.
I have MS3pro.
I have clips for holding the COPs.
I need rubber grommets for the wiring to lower coils.
I have an MSD box mounted above the relay panel and that’s where the MS3 is going.

[gsxrken]

Good luck! Another graduation out of the CIS PTSD crowd.

[lite75]

Looking good!

[Bucketlist]

Good job...
I think of this conversion often even though I don't drive the car enough to make it worth while. As a project it sounds like a fun challenge. Were you able to recover some of the cost by selling off your old cis parts or will you keep them for the next guy. Will you post your total investment in efi?

[T77911S]

i thought about starting a thread for everyone to post pics of their conversion.
wire routing, mounting the ECU, things like that. also sourcing parts.

I think I am going to use heatshrink tubing to house the wires. not a fan of wire loom.
it would also look kind of factory that way.

how did you terminate wires that were not used.

was thinking about running the harness for the right side of the engine across the top of the fan shroud but still not sure about getting the wires to the lower COPs. I don't want to cut 6 holes.

[Rich76_911s]

Is this an ignition-only setup with the MS3Pro?

[T77911S]

to start with

I will do efi later.
I don't want to deal with trying to setup efi and ignition at once.

[flightlead404]

Originally Posted by T77911S

was thinking about running the harness for the right side of the engine across the top of the fan shroud but still not sure about getting the wires to the lower COPs. I don't want to cut 6 holes.

I don't see why you can't run through the sheet metal in front of the engine and down to the LHS and also over the flywheel to the RHS without cutting any holes, or at most one.

[Rich76_911s]

Originally Posted by T77911S

to start with

I will do efi later.
I don't want to deal with trying to setup efi and ignition at once.

That's fantastic. I've been thinking of doing the same thing. Excited to follow along and see how this is done.

I'm currently running Electromotive XDi and want something with more control and knock sensing. Might be a project for this winter.

[David]

I went with wasted spark coils mounted on the firewall. My EFI connection is on the right covered with gray duct tape. 4 channel CDI mounted on left side. At the time I built it, there wasn't a 6-channel available so I'm just using 3 channels split into 6. One of these days I'll spring for a new 6 channel (or switch to coil on plug).

I left a bunch of extra wires for future items like traction control, fuel pressure, oil pressure, cylinder head temp, and before intercooler temp. I terminated these with a little piece of shrink tubing on each wire.

[jons911]

Did you just go with the stock 3.2 head temp sensor? I've been trying to find a more suitable replacement for mine since stock curve only goes to around 250 F I think.

[David]

Originally Posted by jons911

Did you just go with the stock 3.2 head temp sensor? I've been trying to find a more suitable replacement for mine since stock curve only goes to around 250 F I think.

I never installed a head temp sensor, just engine temp.

[jons911]

Sorry, should have specified. I meant the OP as he mentioned buying a head temp sensor.

T77911S: same question on the head temp sensor.

[T77911S]

i used the 3.2 sensor but mounted it on the inside of #1 head along with knock sensors on 2 and 5. drilled and tapped the heads.

[T77911S]

I did all the sensor stuff when I built my motor "just in case" me or the next person wanted to go EFI.
had the flywheel cut for teeth, did these and cam sync.

[jons911]

Thanks. My search continues.

[mrm930]

My 930 is already twin plugged with internal goodies completed by Supertec. Trying to get it running on CIS. Because a few years ago I sent the whole system to Chris at TurboKraft to rebuild and "jack it up" a bit. Drive it for a few years then (money needed).......

Then - EFI....

[JakobM]

Originally Posted by David

I went with wasted spark coils mounted on the firewall. My EFI connection is on the right covered with gray duct tape. 4 channel CDI mounted on left side. At the time I built it, there wasn't a 6-channel available so I'm just using 3 channels split into 6. One of these days I'll spring for a new 6 channel (or switch to coil on plug).

I left a bunch of extra wires for future items like traction control, fuel pressure, oil pressure, cylinder head temp, and before intercooler temp. I terminated these with a little piece of shrink tubing on each wire.

Nice setup and placement! Alot of juice in those coils I assume. Great documentation of wiring, and nice thought out extra wires shrinked for later add-on features

[parts4porsche]

I hope I am not disturbing this thread.

Could you tell me the advantages of twin plug turbo engines? As I see the 993 turbo is single plug. The pistons are mostly flat top.

I am to build another engine for my car and still not decided yet. If going o twin plug or single plug.

I have both heads rebuilt and ready to go. One is stock 3.2 heads and the other one is 3.3 with ported intake to 41mm and twin plug.

Thanks you guys!

[David]

My understanding is when the piston gets pretty large like the 98mm many of us are using, the twin spark helps get a complete fuel burn. There is quit a bit of debate on the topic since the turbo pistons are flat. It would be nice to see the timing and dyno runs on two identical engines with and without twin plug to see if you get more power with twin plug.