Isis Multi-Plex Help !!!! ???
 

Hello all , didn't know where to post this , so since its a single turbo-ed FD I decided to put it here ! mods feel free to move it to the appropriate section if required , so on with the story ! I've driven my last set up for about three years with a couple challenges along the way , I fought numerous oil leaks (Excessive oil pan!) , a slipping twin disc clutch and an extreme blow-by problem ! At the end I popped the rear rotor because of a flattened fuel line ,!!DO NOT use aluminum tubing for fuel line under your car.
I started my new rebuild to not only make it better but more reliable !The motor will again be semi peripheral with 1.25" ports , have unbreakable apex seals , solid corner seals ,Pineapple racing o ring and water seals all other seals stock. I also put in the "high performance" RX8 stationary gears to allow even more safety when going to my 11K rev limit ! the block is also studded (over-sized) and uses a 2 piece e shaft with center roller bearing.Sold my last intake (Holley styled TB and Pro Jay manifold) and purchased the new PRO JAY lower EFI intake and fabricated a custom upper manifold featuring 2.5" I.D. runners , twin 75mm Mustang TB's and a large plenum (D shaped from Ross machine). I upgraded the drive-train starting with an OS giken triple plate clutch, OS gears set equipped gear box with large capacity stiffening oil ( I finally finish the rebuild!) , purchased and installed an OS super lock LSD with a 4.44 ring and pinion set along with a Greddy diff cover and a custom diff girdle , fabricated a rear sub-frame mount and added reinforcement to it as well as purchased and installed the 1000 HP axles /hub kit from the Drive shaft shop.
At present I am waiting to receive my motor back from my builder ,whilst waiting I am planning how I am going to put everything back together which brings me to the wiring , its horrible ! The original vehicle harness is old and dirty with wires running all over the place and my stand alone has made a bad situiation even sorse since it controls everything via relays and is tied to it at different points !
I started looking at wiring solutions and came across the RACEPAK smart wire which seemed ok , but was limited to only 15 inputs and was $1500+ USD ! I eventually found the ISIS multiplex system at ,http://www.isispower.com/products.html which seemed very capable of doing the job and simplifying the entire wiring system in the car , the price wasn't bed either ! I spoke to one guy on my ECU support forum about it but he was very negative about it since he kept comparing it to the VERY expensive MOTEC pdm which was ALSO very limited (for my use) with only 16 inputs ! so I'd really appreciate some info to help me make up my mind!
So finally ...... DOES ANYONE ON HERE HAVE ANY EXPERIENCE WITH THIS SYSTEM ??? PLEASE POST IF YOU DO !

Thanks for reading !

I haven't used the ISIS system, but have been around a couple of racecars with Motec PDM's installed. They help simplify the wiring quite a bit on a from-scratch build.

I'm a little surprised to hear you need more than 15 outputs, though.

1. ECU, dash & other misc electronics
2. Fuel Pump
3. Power for Injectors, Coils, other misc 12V solenoids
4. Electric water pump (maybe?)
5. Water/meth kit (maybe?)
6. Headlights (low beams)
7. Headlights (high beams)
8. Turn signals (left)
9. Turn signals (right)
10. Starter Relay
11. Fog lights
12. Brake lights
13. Second fuel pump?
14. Nitrous?
15. ?

Thais may be true but the Motec PDM is more than three times the price of the ISIS ! I am not willing to pay soo much to be able to eliminate fuses and relays.

those items you listed are for the car alone , my stand alone is integrated into everything i I have a couple 'extra' items on my car like an intercooler pump and fans , accumulator solenoid , vacuum pump , 2 WI solenoids etc.

I'm not saying the ISIS is bad or that the Motec is better, I'm just saying I haven't used it and don't know anyone who has. Did the guy from your ECU forum have a bad experience using an ISIS, or was he simply saying he had good results with the Motec and recommended it? I agree Motec parts are pricey, I don't have anything from Motec on my car.


Don't assume each individual part on the car needs to have its own channel, if both your WI solenoids can always be switched on or off at the same time they can both use the same channel. Also, there's no rule that says you can't add a few relays to the system, just use the Isis as a fuse.

He did not say its bad , but he said that it did not reduce wireing time by much compared to traditional wireing kits , this seemed important to him since he runs a shop so I guess time is money.this factor for me is unimportant since I do not run a shop , it would be a one time install. As for my ECU wireing I have it all figured out , thanks for your input though.

If you're talking about opinions from EFI101, Brian Macy (TurboNova) over there seems to have a pretty good opinion of the ISIS. I'd try to pick his brain, if you go that route. Motec also has a lest expensive series of PDMs without the Autosport connectors. These are the same units that Racepak is selling as well. Just throwing out another option for you.

I've got my eye on the Racepak PDM for my own project, but it will be another year or two before I get to that point.