blue94

iTrader: (7)

I think I'm going to have to change opti's again after less than 2 years, and I'm thinking about upgrading to the vented style. I know the harness is different and it is connected to the cam differently, so what exactly would I have to change on my 94? Would I have to change to a newer cam and the newer style opti harness?

Formula350

iTrader: (3)

Cam is fine, but you need a crank sensor with the updated timing cover.

rbrcka

You could also consider an MSD Pro Billet Opti. It is a better design than stock and is vented as well. Just another option to think about.

Fastbird93

iTrader: (10)

This is incorrect.

Items you'll need for the conversion:

Vented Opti
Camshaft with LONGER dowel pin
Opti Electrical Harness
Opti Vacuum Harness
95 Timing Cover (this does NOT have a CPS sensor port)
95+ Timing Set

Total conversion cost should run around ~$500 give or take. Since you've got to pull the cam, might as well throw some springs on there and do a healthier than stock cam.

matt94z

iTrader: (49)

He is correct. I bought a used timming cover and harness on ebay. Saved about $50. I wouldn't do it unless you were going to do a cam swap.

B4CZR2

just buy the MSD Pro Billet... It gives you everything you need to have a vented set-up. Thats what I got. Its a little pricey but idea is to do the job once and not have to worry about doing it again.
Check out the thread I started about my opti project:
https://ls1tech.com/forums/lt1-lt4-modifications/734691-new-opti-install-pics-video-funny-commentary.html

KTM

OK....Hold on here....ALL YOU NEED is the CAP for a '95 up. Everything else works just fine. You need a '94 distributor and a '95 cap. Then all the hoses to plumb it in. I did this on my '93 Vettte - no problem. I ordered a distributor for my '93 (same as '94) without a cap and then seperatly ordered a '95 up cap. Then I ordered the hose assemblies that comes with the little check valves and filters. There is nothing wrong with the distributor drive mechanism on you '94. The '95 up may be a little nicer and easier to put together (harder to screw up at least) but there is nothing wrong with the '93 & '94 versions. And the wiring harness plug will plug right in no problem.

B4CZR2

I never knew you could do it that way. Great if all you need is the cap and rotor.

rbrcka

MSD makes a vented cap setup to go with the stock non-vented Opti as well.

Rowdy94

iTrader: (13)

IIRC, the newer style opti swap gives you the opportunity to run a nicer timing set. With the older opti, you basically have to get another original if you're going to swap it if and when you do a cam.

Just something to consider.

litch2004

iTrader: (1)

If you just go with the vented cap it isnt the full vent. The vented opti goes from the air intake into the top of your cap. Then a true vented system will continue from the bottom of the distributor and it will tie into the vac. line right by the PCV valve. If you only get the vented cap from like the 97 (which were truely a vented opti) then all you are going to be doing is have a line from the cap to the air intake tube, which might move a little bit of air but not much because the cap is sealed to the distributor, with is also sealed. The purpose of the line from the distributor is it will suck in air through there through the cap and through the line coming out of the cap.This allows fresh air to run through it and keep it dry. So the misconception of just putting on the vented cap off of the newer vented systems will not work.

IMO the MSD is a better way to go or any other conversion vented opti, that will still use the sock cam and timing cover. The MSD comes with everything you will need (including vacuum lines, harwired opti harness, the timing spline is built in, cap and rotor) and you save the time and worry about trying to change out the cam and cover. If you are planning to change the cam already then i could understand chaning everything over, but not just because the opti is going out or wanting it vented.

Pampered-Z

All the info you'll need:

http://para.noid.org/~muttvette/opti.html

94 F-body

iTrader: (1)

I have a good one, I have an 1994 Trans Am GT and I am putting a 1995 Caprice Classic Intercepter motor in it, (that was the first motor that was close to my budget and car) is there any thing I need to know/or be aware of ?

KTM

Memory is coming back to me....I did drill a hole and JB weld in a fitting to hook the vent hose up to the distributor. My Vette has BOTH vent lines - one from intake manifold (vacuum) AND one from the air cleaner boot. The cap from the '95 does only have one of the connections needed. You have to add the other one. It's easy and a lot less work than changing cams and timing covers though...I did mine several years ago, forgot about that detail, sorry.

Taubr Unit

iTrader: (32)

why spend the hundreds of dollars to put a new opti on when you an convert it to a coilover style and not even use the opti anymore? Thats what im gonna do when mine goes. Screw spending $500 on a new opti when for maby $100 more you can get a system that wont fail. Just my 2 cents.

Fastbird93

iTrader: (10)

Ding ding ding, we have a winner.

Because you still need the opti for the Delteq and LTCC.

blue94

iTrader: (7)

exactly and the computer did throw code 36 (optispark high resolution signal faulty) which from what I understand would mean I would need a new opti in addition to the delteq or ltcc kit. If I had an abundance of cash that wouldn't be a big deal, but I can't spend that kind of money right now. The MSD is starting to sound better and better since I won't have to change my timing cover or cam and it still has the provisions for the vented system. If I do that, would I just need to buy all the vaccuum hoses to vent it, or do they come with it?

and who seems to have the best prices on the msd optispark?

litch2004

iTrader: (1)

That is true about the deltec and the LLTC mod. But if you read on some other previously discussed threads the opti is not what goes out. It is actually the cap and rotor design its self. When replacing a cap, you cannot get the center (piece between the cap and the distributor) unless you buy a whole new opti. This is one of the main reasons as to why peoples distributors go out again. Replacing the cap and rotor will save you sometime as it did for me but without replacing that other piece you are still going to get water or moisture build up in the cap because the gaskets are dry and cracked causing it to go out. The opti sensors that are used in the GM opti are made by mitshubishi, in which they are still using that same design on their vehicles today. Deltec sells a piece that after removing the cap and rotor, you replace it with their billit cover. You can just remove the internals out of it and silicon the holes up and silicon the cap to the opti if you are low on money, someone I believe not sure of his actual display name but the s-10 with the LT1 in it, did on his opti. Both will work, one is just an appearance preference. The other reason that the original design optis go out is stated that the (not sure of proper name) way the plugs on the side of the cap for the plug wires are placed so close together that you receive arc over from one to the other. Resulting in a bad opti.

If anything that I have stated is incorrect please correct me. This is mainly from own experience, talking with GM, and from other information posted on the LT-1 opti systems.

blue94

iTrader: (7)

that is all great, but since I'm getting a faulty high resolution signal trouble code, I will have to replace the whole distributor not just the cap and rotor. The high resolution signal code indicates a problem with the optical portion, not the cap and rotor.

Taubr Unit

iTrader: (32)

Ok, well if you buy a msd opti for $500, the deltec kit is $650 and comes with everything, so i would assume that means a new optical pick up. So for the extra $150 you get a WAY better ing set-up correct?