944Hybrids: 924/944/968 and 928 V8 Conversions
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HOW TO DO AN ADVANCED SEARCH.

Mon Jul 08, 2013 3:56 pm by Admin


For the benefit of 944Hybrids users there are two search functions available for you to use.
The purpose of this sticky is to explain the "Advanced Search" function because it is much more powerful and is the best choice when researching information.

When you log on to the site a list of options is shown in a line at the top of the page. One option is labelled "Search", use this option (NOT the search box lower down on the right).

After you click on the upper search option, a drop down box appears. At the bottom of this box is a radio button marked "Advanced …

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Post  v8944 Sun Aug 29, 2010 9:03 am

well, it looks like whoever said distributor was right...driving the car to a pca meet yesterday, all of a sudden the engine just shut off, HUGE backfire, and nothing. Car won't restart, although one time i tried restarting, after i stopped cranking it dieseled for a few seconds, so i shut if off all the way real quick.

i wasn't doing anything outrageous to make something like this happen, i was just cruising at about 70 and BANG, nothing...

so now i get to tear it back down again...this time i'm not going to rely on a cheap distributor to try to fix my problem...

so here's my question: Should i save up and buy an msd billet opti? or should i save up a bit more and build/buy a delteq 4-coil setup to delete the high voltage from the opti and hopefully stop having these problems? (which are most likely the product of cheap chinese crap and user error... Rolling Eyes )

thanks guys...

p.s. the big question is whether i should pull the motor and sell the pieces and buy a pullout LS motor to toss in...i really know this motor pretty well and i don't want to get rid of it...but it needs a lot of work, should i give in? Shocked


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Post  Admin Sun Aug 29, 2010 11:29 am

Just drill a hole and and install a regular distributor in it.

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Post  Porch Sun Aug 29, 2010 2:44 pm

You might check the coil too, but probably the opti.
MSD's quality has just gone to $#** lately, i wouldn't buy ANY of their products, but that's just me.
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Post  v8944 Sun Aug 29, 2010 2:51 pm

how do ya do that? i just did a little research and from what i can see, you can do it with a carb conversion, but i haven't seen anything with fuel injection...any walkthroughs you can point me toward?

thanks!
Ethan
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Post  v8944 Sun Aug 29, 2010 2:52 pm

everything but the opti is BRAND NEW, not used, not remanned, brand new...so i guess i could check that, but i'm almost positive this is the opti

oh, and thanks for the tip on msd!

edit...it looks like you just have to drill a hole in the intake manifold to hook up an HEI dizzy...anyone know where?
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Post  v8944 Sun Aug 29, 2010 4:41 pm

ok...new question:

if i were to drill the intake and install an HEI distributor...how would i tell the computer to fire the injectors? i've read that the engine computer needs a signal from the opti to deliver fuel. Could i just leave the opti installed minus the rotor and plug it in so the PCM would see timing?
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Post  Admin Sun Aug 29, 2010 4:58 pm

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Read here

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Post  v8944 Sun Aug 29, 2010 5:55 pm

read the whole thing...didn't answer my question about using the optical disk to read crank/cam position to time the fuel injectors...any ideas about that? i see he used a haltech computer, is that entirely necessary for a rather mild swap like mine?
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Post  Wild Bill Sun Aug 29, 2010 8:09 pm

If you want an option you can "Megasquirt" It.. You can use the opti to trigger however if that is what you feel is failing I would crank trigger it like I did. See I modified a Gen I SBC with a LT1 intake and didn't want to cut a hole for a distributor so I fabbed an oil pump drive and installed a 36/1 missing tooth crank trigger wheel.
Opti.. [You must be registered and logged in to see this link.]

I used "Megasquirt II" code and it can run individual coils if you want however I used Ford EDIS commonly found on Crown Vics etc. They use two 4 tower coils in a wasted spark configuration and are a solid ignition system that is controlled by the Megasquirt. Only downside to EDIS is the coils have strange coil ends on them, I don't know if you can buy the terminals seperate however I needed wires anyways and the rest of the ignition system with harness cut off's came to $25.00.

It takes a little learning and time especially without me using a dyno because you want to make gains safely however playing with fuel and spark curves is very rewarding. I have also installed a wideband oxygen sensor that inputs fuel ratio from about 10/1 to 18/1 so the computer can better utilize the autotune option. you will still have to go to the tables and blend but in the beginning the info can sure help!

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Post  v8944 Sun Aug 29, 2010 9:16 pm

i've looked at megasquirt a lot in the past...and i have NEVER understood any of the stuff on their site, probably because i don't have it in my hands. It can't be too complicated, but it sure as hell looks like it! right now i also don't have the cash for a MS system, no matter how cheap it is, so hopefully i can figure out how the fuel pulse is triggered and do a cheap retrofit with a vacuum advanced HEI dizzy and just not bother with the opti for a while...although if the optical disk in my opti is doneski, i'll be looking for something a little different i guess...

EDIT: just reread the first part of your post...are you saying that the opti does trigger fuel pulse and leaving the harness plug installed but unplugging everything else will work to trigger fuel injector pulse? because that would make this VERY easy!
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Post  Wild Bill Sun Aug 29, 2010 9:41 pm

Opti is complex. The easiest solution is probably to fix the problem...
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When GM went looking for a new ignition design for the LT1, they went with a somewhat unlikely source - Mitsubishi. They bought an optical distributor system that was already in use in many Mitsubishi, Chrysler, Subaru, and Nissan applications. The stock ECU uses the 360 slot ring to determine crank angle and the inner ring of eight slots to identify the cylinders. MegaSquirt does not need or use the information provided by the second ring of 360 slits or the length of the inner slits, so you just need to obtain a signal from the trailing edge of the ring of 8 slits. This writeup covers using a BIP373 Ignition Driver for controlling the coil.

I also didn't build my own, only so much I need to learn..
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Post  v8944 Sun Aug 29, 2010 9:47 pm

well there isn't much difference between using the optical trigger from the opti or a crank trigger, you've got to read it somehow right? if i can remove all of the voltage from the opti and just use it as a cam/crank position sensor to fire the injectors it should last a good long time...the optical trigger itself isn't the design flaw, it's the tightly run contacts in the cap and around the rotor to allow right and left bank specific plug terminals...so you don't have to run plug wires all around to different sides of the opti.

i guess i'll pull the fuel rail tomorrow or tuesday and pull all the voltage from the opti and see if the injectors pulse when i crank it, that'll tell me for sure whether my idea will work!
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Post  Wild Bill Sun Aug 29, 2010 11:41 pm

No real experience with opti so I don't know the flaws either. Sure be nice if you could trigger like an Edis module with the optical. Just thinking?
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Post  stu wright Mon Aug 30, 2010 7:40 am

a while back there was an article in hot rod about a company that makes a coil pack style ignition that uses a crank style trigger to fire the coils that are mounted to the valve covers and deletes the opti.you just plug the hole.il have to dig through my giant stack of hod rods to find it unless one of the other members are familar with it.i am all to familiar with opti problems as i have owned a couple of cars that used them.the conversion is about 600 bucks but makes alot more dependable ignition for the lt1.the placement of the opti is very suceptible to contamination which the opti is very fragile to.your other option is drill hole and use a top mounted msd billet dist setup to fire the coil and posibly use somthing like msd digital 6 plus like i use on my setup which gives a lot of spark energy to help with power adders also with such things as spark retard and rev limiter.you have several options you can utilize.or the mega squirt.trash the opti .
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Post  v8944 Mon Aug 30, 2010 8:58 am

i think you're speaking of this...http://www.bailey-eng.com/LTCC.html or [You must be registered and logged in to see this link.] (they're out of business though). There's also a company that makes crank triggers and cam triggers and allows you to use the LS1 wiring harness and computer to fire a separate ignition system...this may be in my future!
the LTCC swap still uses the optical trigger though, so it will be doing essentially the same thing that i want to do except i won't be using 8 coils. The swap i'm hoping to do will most likely create some tunability restrictions, but as a "get it up and running reliably" solution i don't think it can be beat for the money!
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Post  948 Mon Aug 30, 2010 11:59 am

I have been using a stock GM vented opti for 5 years, no issues so far. I did add some RTV to the outer casing, to reduce the chance of liquid entering. I bought it through Jason Cromer at Sam Taylor dealership. <== back then his prices were wholesale.

If you go with the Deltec you will need an opti with a good clean optical sensor.....
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Post  944-LT1 Mon Aug 30, 2010 12:51 pm

I have been using a stock GM vented opti for 5 years, no issues so far. I did add some RTV to the outer casing, to reduce the chance of liquid entering. I bought it through Jason Cromer at Sam Taylor dealership. <== back then his prices were wholesale.

If you go with the Deltec you will need an opti with a good clean optical sensor.....

I did the exact same thing and got it from the same guy. This was roughly 6-7 years ago and it still runs like new. I say, the best and most reliable way to fix your problem is to buy a new Genuine GM Optispark.

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Post  Dawgz83948 Mon Aug 30, 2010 12:53 pm

MSD.
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Post  v8944 Mon Aug 30, 2010 8:18 pm

looks like others are saying msd's quality is going to crap....and if i can drill a hole and spend 100 bucks on a new distributor and call it a day, i will. I'm not going to keep throwing money at opti's, i've had two go bad, granted one wasn't gm, but the other was, and i'm not going to drop 450 dollars (that i don't have) on another fricking opti that's going to last 1000 miles before it blows up...i'm sorry if i seem unreasonable, but i can't ignore my own experience speaking, i don't have the money for a new gm unit, and i don't really feel like dealing with the BS associated with doing opti swaps over and over again...

jeez maybe i should just pull the engine and sell all the parts off of it and let the car sit for a few years until i can make enough money to do a decent ls swap

dammit...maybe i should just spend the next 6 months saving up to buy an opti...i just really DON'T like that idea at all...even if the GM unit is supposed to be indestructible for some period of time, if i do kill it in 6 months i'll be exactly where i am right now, except out another 450 bucks.

GRRRRRRR Evil or Very Mad
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Post  Admin Mon Aug 30, 2010 8:41 pm

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Look at that one, yes it's used, but the guy selling it is about 3 blocks form me and I get stuff from him all the time. I've never gotten anything that didn't work. I'll go get it and ship it to you if he won't ship it to you. If you contact him , tell him that I ( Eric the Porsche guy) sent you to him. He'll take care of you.

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Post  v8944 Mon Aug 30, 2010 8:50 pm

thanks eric, but i have a 97, an early non vented opti won't fit on my cam will it? I'm down for trying a gm unit for 50 bucks...i'll try emailing him to see if he has a later vented type.
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Post  Admin Mon Aug 30, 2010 8:53 pm

I honestly don't know, I don't see why it won't fit. Ask Robbie (he's the one with the opti for sale)
He'll probably know. Camaros are all he deals with all the time.

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Post  v8944 Mon Aug 30, 2010 8:56 pm

just looked it up a bit, the early non vented optis actually require a different cam and a different timing cover, but i did just email him and ask him if he has a late one he would sell me

thanks for the lead, i appreciate it!
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Post  v8944 Wed Sep 01, 2010 1:23 am

Eric, thanks again for the recommendation...Robbie hooked me up with a working opti from a late car. He's shipping it to me tomorrow. My plan is to go ahead and install this opti and run it for a while...i will add some rtv around it to help keep moisture out of it, and i'm planning on pulling the intake manifold and timing cover and resealing them both (and maybe installing the crankshaft position sensor that i forgot to install the first time i built the engine....???). This will also be a chance for me to check all of my work and make sure nothing I did is coming loose. If i can come up with the money, i'll be replacing the lifters, pushrods and valve springs, buying new bolts for the motor to replace the pieced togetherness of bolts and fasteners on my engine, and i hope to reseal the intake manifold, the front timing cover, as well as maybe doing front and rear main seals and the oil pan gasket.

question...is it possible to do the front and rear main seals on a 97 Pontiac Firebird Formula motor without removing things like the crankshaft and clutch assembly? or am i going to have to live with the leaks from those two places until i decide to pull the motor and do some other work?

Thanks!
Ethan

P.S. i'm planning on saving up to do a LTCC conversion in the future, mainly to remove the high voltage from the opti, plus it will give me the opportunity to make custom fuel rail covers to mount the coil packs on (woot!)
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Post  948 Wed Sep 01, 2010 6:55 am

I would suggest that you clean the inside of the replacement opti and replace the rotor before installing it. I would suggest flushing the whole unit, including the optical sensor, with isopropyl alcohol. Do a search online, you will find a few write-ups on ow to clean the opti...

You can change the front seal while the opti is off; it is in the timing chain cover. The rear main would require the removal of the clutch/flywheel...
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