So after 500 miles my cheap autozone opti went out. When I got it out the car yesterday, i took the cap off and the rotor and rotor screws fell out. If I didnt have the ltcc conversion, the dang car would have never made it home..

Anyway I bought a Msd pro-billet Opti and installed it last night. Well My car is a 1992 and MSD failed to include or tell me that I needed a wiring harness from EFI Connection to make the msd work in my 92..

So I want to start the car bad today and I am wondering if anyone has ever bypassed the OEM harness and made it work and if so do they have the wiring schematic. Its only 4 wires but I need to know exactly which go to each?

 

I have the same unit MSD P/N 8381. So, I assume the wires are the same, but you can confirm the colors from what I've provided.

Harness side To Opti side

Black with red stripe to Brown with yellow stripe
Purple with white stripe to Brown with orange stripe
Yellow To Red
Black with pink stripe to Red with blue stripe

Note* I have the correct opti harness plug installed so I don't know if the colors changed on that end.

If you decide to wire up on your own make sure you use weather pack connectors and some type of sheathing on your harness.

 

You "whack" at anything there goes the warranty - it might be painful but I believe I'd do it with the harness needed from "them" and there can be no issues. Not knowing who you bought from it's hard to tell what they might offer BUT if there's concerns check before "whacking"!

Why didn't you give A-zone the opportunity to correct it?

 

Also, make sure you loctite any mounting screws inside the opti so they don't back out. Even if you have an MSD unit this should be done.

 

look at this post, especially 4 http://forums.corvetteforum.com/c4-t...connector.html

 

Order the adapter from EFI Connection and do it right the first time. EFI has been in business for awhile so I would bet they use the correct wire, a good connector and it is "plug and play". The connectors you use to adapt it yourself may or may not last with engine heat and may not be very weather tight. If you make a simple mistake - you may need a new opti and computer.

 

I have another harness that plugs into the msd side of the wiring. I didnt plan on cutting that to pieces. I was going to chop the factory opti side because its a short 1 foot harness that plugs in on the top of the intake on the passenger side. That is replaceable.

As far as autozone goes, They gave me a credit for the price of the opti I bought from them. I bought the raptor brand because the LTCC only uses the low side of the opti and I didnt figure I needed something expensive., After having it go out so soon, I decided not to cheap out on the next one plus the MSD is vented and has a -/+ 6' timing adjustability.

I did use blue loctite on everything on this one. I wont make that mistake again.

 

Thanks 93, That is what I needed. Repinning the oem harness is a heck of alot better that splicing or spending the 35 plus shipping on a harness that MSD should have supplied in the first place.

 

I don't recall what your connector looks like on the end of the harness but if it's four flat then I believe a 4 wire LS alternator connector might be indexed correctly to use it and you could probably do that today in a local auto parts store.

The A-Zone might be a 494 and you could check it for fit. Any auto parts store should be able to change the GM 15306009 to what ever they sell. Will it work? Don't know but it's a short drive to find out I'd think. EFI has a $25 minimum and then there's the ship. If you find it fits I can give you an empty connector number and terminal numbers to get them easily. Maybe a couple days for the connector but terminals will be at any dealer or some quality AP stores.

If you had your old trashed '92 opti you could do a cut/splice of it to the connector I referenced to get up and running and then use the empty I give you the number of and some pins and do the repining. I need to know if it fits!!!

 

Thanks!

I have the Ltcc conversion from bob baily and he has offered to send me the connectors I need to repin the harness! I work all week and they are calling for snow already so it looks like the car will be parked the rest of the winter.

I guess that gives me time to replace all the bushings in the suspension, the rear shocks, and add meth injection and a smaller pulley on the procharger.

 

Is autozone going to come out and replace it properly?

Why would you want to invest all that time to replace it with another piece of crap?

This is another cheap optispark thread... (yes even the msd is a cheap opti. its a crapshoot if that one will work/ how long)

The only acceptable optispark is ac delco new old stock (not remanufactured) or delphi....

 

Ofcourse they didnt.

I've heard mixed opinions on the MSD and I decided to go with it and see what happens.

thanks, Ill remember that incase the MSD goes out.


Yes there are tons of opti threads out there and you know what? I highly doubt the threads are going to stop being posted as long as there are lt1 cars around. GM designed a POS when they decided to go with they opti. This is the first Opti I have replaced in my car and it was a learning experience and really not difficult at all. I wont be posting another one but Im sure someone in the near future will.

Thanks for all the help gentleman. This forum is a great source to find the quick answers a guy needs when working on his Hobbie car.

 

FWIW, I have a friend who has a msd opti, and he turns it past 7000 rpms on a regular basis. He has had it for several years and it has done well.
I have a delco opti, with about 10,000 miles on it. With my new motor, it has been to 7000 rpms, but usually shift at 64-6600. I did use thread lock on the rotor screws, but again, so far so good.

 

I set my rev limiter at 7k and it will see that RPM regularly. Im at 58,651 miles as of today! Lets see how long the MSD lasts.

 

so tell us about your build!!

 

Its just a 383 with a forged bottom end, Afr 210 heads, Jessel 1.6 Shaft mounts, Port matched LT4 intake, 60 lb injectors, Comp 280 xfi cam, Good 3" exhaust with 1 7/8 step headers from ARH, a P1SC Procharger with only 7.3 psi at 6500 rpm for now and a fadanza flywheel with a centerforce D/F clutch. And the other million new things to complete the build right.

I am using the single Procharger intercooler but I plan to get rid of that and reduce my pulley size from 2.95 to 2.65 and add a decent meth/water injection kit. I should beable to pull 12-13 psi out of the blower with the help of the 8 rib set up from blowerworks.

The car runs amazing now that I have a new OPTI. It made some good power at the wheels but not quite what I expected. I believe it will exceed my expectations after I complete the car over the winter. Aside from the engine work, I need to find a good happy medium with getting that power to the ground. The car has the factory 3.56 gears and I get wheel spin bad through 3rd gear. I am running a f1 315 on the back. I definately need to get some ET streets on the thing.

As far as tuning goes, I had the car tuned at a company here in Wisconsin. It took a long time because the tuner was more adapt to the OBD11 stuff and the process of getting everything right took awhile. I do plan on getting everything I need to datalog and tune with this winter. I cant expect to have such a hobby and not beable to tune the thing myself. Afterall dyno time is far from cheap.

This whole thing with this car has been a learning experience for sure and its far from over.

 

This is awesome. You are one of us!

Ive got a P600B on my 1993 6spd vert with stock bottom end lt1, greg@blowerworks 8 rib dedicated drive bracket pullied to 12.5 psi at 6000 RPM, AFR195 comp ported heads, meth/water injection. 9.7:1 compression, 224/236 lloyd elliot spec cam and the same ARH 1 3/4 to 1 7/8" stepped exhaust that you have. Walbro 255 l/hr & GSL392 pump feeding 60 lb/hr injectors. I run the moates ostrich and do the the tuning myself as most of the tuners are 'tards on OBD1.

I too am a fan of the fidanza flywheel and I have a spec stage 3+ clutch.

It made 510 rwhp at 5400 rpm and was still climbing but I kept shutting it down early to dial in my AFR and I ran out of dyno time.

before the end of this year, I want to rev it up to 6400 on the dyno

Boost and nitrous have got a bad name due to too many people not knowing what they are doing.

Inadequete fuel, lean-outs, too much spark advance.

Meth/water injection is my key to making the stock bottom end work fine - dont get me wrong I will build forged 383 the next time in the future.

 

Thats alot of power on the stock bottom end

I had some broken ring lands when I initially got my car due to it being set up and ran with the FMU that procharger included with their kits back in the day. I deleted all that and went with a aeromotive stealth pump and regulator and ofcourse the injectors.

how does your car hook up with that kind of power? What suspension mods do you have?