We just bought a 94 Torch vert (49,000 mi) for my wife, who won't drive our 6 speed, C5 Coupe. Now I have to learn all the inside skinny on C4's, too. I guess it will be worth the effort because the boat - er' - Buick is out of the garage and 2 Vettes make it look sooooo much better! I guess I will posting in both worlds now - for which I am very greatful. I also wonder how my wife will react to mods I want for her car. I never thought we would have 2 Vettes - and it only took me 55 years to do it! Next time around I'm going to Medical school ----- :thumbs:

 

:thumbs: :seeya

 

Welcome! Sounds like you got a nice C4 there!

My first advice, change every fluid you can... get the tranny powerflushed!!! Get all that nasty crap out of there.

Same for the coolant...

NOTE: Powerflushing is just that, a couple of companies are now providing powered and filtered fluid flushing systems. BG Products being one of those companies. Good stuff.

Replace all hoses and the serp belt.

Check for oil leaks!

-Intake
-front main
-rear main

Good quick mods:

-open lid for the air cleaner (plus a K&N airfilter)
-cat back exhaust, I recommend Corsa.
-R-D Racing Camber brace - really tightens up the front end.
-Throttle body by-pass. stops hot water from the radiator from going through the throttle body.

Mods to avoid:

-air foil... ugh.
-mr mojo :jester

The biggest known "problem" with LT1's is the distributor. It is called the Opti-spark. The unit is mounted below the waterpump on the front of the engine. It is not a real "problem", just requires replacement every 60k to 70k miles.

Here is the rub - there are 2 versions, 1992-1994, and 1995 to 1997. The later version is much better, but, without a major parts swap, is not compatible.

There are some aftermarket options, but they are vague at best. Actually, the most promissing, Dyno-Tech Engineering, seems to be vapourware at this point... lots of talk, and now they are getting cold feet.

LTCC is another company, it allows you to replace the opti's high voltage section with coil packs from an LS1 motor... neat trick. You still use the opti as a crank trigger.

The basic problem with the opti is its location. It is vulnerable to coolant seeping inside the opti and eating up the bearings. And guess where the weap hole from the waterpump is? :D I am considering a bypass hose for that weap hole.

The later opti's are "vented". This means they are using positive engine vacuum to suck air through. This is adaptable to first gen opti's with little effort, and the part is only 10.00 or so. GET THE GM PART - it is the best way to go. The aftermarket "solutions" don't work in a filtered closed loop. And they are more expensive. Go figure.

On last thing... when replacing, seal the opti's cap with RTV... that will help a TON! And don't bother replaceing the cap... the labours the same, and the part cost just does not justify it.

That's about that! Sure sounds like a sweet ride!!! :cheers:

:seeya

 

THANKS for all the info! :thumbs:

 

:cheers: :thumbs:

Get the wife signed up and add another face to the forum...

:seeya

Mark

 

:cool: :cheers:

 

Replacement at 60 - 70K :confused: On my coupe, I got 85K out of mine. On the earlier ones (92-94) they do fail. The main reason is because they are not vented. The common opinion on the forum is that moisture gets in and can't easily get out. I just read that on the non vented ones, due to no vent the air tends to ionize contributing to failure. I don't agree with Bogus to not just replace the cap. The cap on the opti is just that a distributor cap. IMHO it should be replaced as a tune up part. But I do agree with Bogus that the top area should have some RTV added to insure a seal. From MY experience, I plan on venting my existing opti unit on my convertible this winter and will replace JUST the cap at that time, along with some additional RTV sealing. :cheers:

 

The 60-70k is a mean norm... sure, others have gotten 110k, but they live in Phoenix!

As for the cap... it's like 150.00, and to me, to save a couple hundred bucks, compared to the labour, gets dicy.

Now... if you have used RTV all along, that's different. Then the insides should be good, and the savings could be justified.

For example... I vented mine, but didn't RTV is. Last spring, April 2002, I got caught in a deluge and drove through a killer puddle - small ocean, I think.

Now my opti is beginning to die. I have the hunting idle... the occasional high RPM miss and stumble.... There is about 50k on my opti right now. So they can go sooner.

One upside. As bad as they can run with a shot Opti, they very rarely just quit.

 

:lol: :lol: :lol: Hey Joe, congratulations! :cheers: Nice to another red vette! :D

 

congrats on the sweet ride

 

:cheers: :seeya

 

Welcome aboard :cheers:

The people here in the C4 section can answer just about any question you have, it's a great resource.

 

Welcome!! :seeya

 

[. I never thought we would have 2 Vettes - and it only took me 55 years to do it! Next time around I'm going to Medical school ----- :thumbs: [/QUOTE]

:iagree: :cheers: I hope I have 2 at 55.Medical school way to long,Medical lawer ya that's it.Make more money with less brain :jester and I get to screw everyone :lol:

 

Welcome to C4 land. You definately got the right color! :auto:

 

:seeya

 

:withstupid: :seeya

 

:cheers: :seeya

 

Welcome and congratrs. Just dont ask which color to paint your calipers...thats for the C5 section...oops. :D

 

Welcome :party: