corvette1271

....after purchasing a very nice 94 c4 with 94k miles on it and a 2 year old water pump without an optispark changeout, it appears that i will be doing the job myself in the future........especially after an $1800 price quote from a local corvette maintenance center......any experienced owners and major difficulties when doing the change out?......one question that i have is timing the new unit when installing it.....

John Row

This is a good DIY job. If you've never worked on a C4 before it'll probably take 2 days. Most of the time, you'll spend scratching your head thinking "How the H*LL do I get a wrench on that?". Another good part of the time you'll be running to the parts store for another tool.

The second time you do it, it takes about 4 hours.

There is no timing to do with an opti spark. The 'puter does it all automagically.

Lots of us have been through this process so there's lots of help.


Here's an excellent article from Corvette Fever on replacing and venting the opti. http://www.corvettefever.com/howto/16758/

I recommend doing the venting as well as resealing the opti with Hi-Temp RTV.

corvette1271

...thanks john.....

JayH

I've done this job three times on my '95 and I agree with Johns assessment.

I live in Kenmore and would be willing to help if you want - It seems to me I even had to 'make' a tool...oh never mind - that was when I was going to replace the rotor without the base. Anyway, let me know.

Jay

DieL

I dont mean to brag at all but the first time i did it the hardest part was just the water pump mess... coolant etc. Now that ive doen it so many times id say its an easy hour job max. I even swapped a water pump at the track for a mezziere pump just to see the diff... its NOT hard at all.

basically you remove the belt... loosen the 6 pump bolts... the pump pulls off.. then undo the opti wires and unbolt it. oh yeah... to get the dampener out of the way i loosened the bolts then hand tightened them leaving a few mm slack. i quickly cranked the car over for half a second.. and it loosened it. remove the bolts and dampener/balancer should slide off.

:cheers:

GlockLT4

I've done it a few times for people and it's not bad at all anymore. I can do it in about 4-5 hours. There is a local shop here that does it for $150 labor!!! :eek: Once you figure out the tricks, it's not that bad. What ticks me off is the price of the damn thing and that they go out ALLLL the freakin' time!

R23HTC

That's why you go with a DynaSpark and hopefully not ever have to replace it again! :D

GlockLT4

better knock on wood there buddy ;) :lol:

R23HTC

For what that dang thing cost, if it dies, I'll be knocking on more than just wood. :smash:

Strick

Here is an article I wrote for the Tech Tips. It might be good reading for you before you begin. Since I wrote this article, two things I would consider: 1) go with a Dyna Spark or 2) go with the Northstar ignition system or LTCC.

When replacing the opti, it's a good idea to replace wires, plugs, water pump (go electric) gaskets if needed to correct oil leaks. I also replaced the serp belt tensor and idle pulley. If you don't have one, get a Helms Service Manual for your year Vette.
https://www.corvetteforum.com/techti...=231&TopicID=2

bogus

I will be honest, they have their weaknesses, but they don't "go out all the freek'n time".

It seems that way, but gee, there are 180k Vettes on the road with an Opti, so the sampling gets skewed.

I have had mine for 4 years... I replaced the opti 3 years ago... I removed the highvoltage side last fall.

That opti, short of a complete flooding, should last for a long long time!

corvette1271

...OKAY........let me know what a dynaspark is......and where do i get one...

corvette1271

...well i just typed in "dynaspark"......and found all i needed to know about one....including the price.....geez.......

leego

Here the website
http://www.dynotech-eng.com/dynaspark.htm

R23HTC

Here's their main page http://www.dynotech-eng.com/

While the price is quite high I think it's well worth it considering how many GM optis I've been through in the last few years. Grant it we buy our optis discounted from people like Chris May, but if you compare the RETAIL price of a GM opti (about $549) to a DynaSpark, there's not as big a difference. Did you read all the defects the DynaSpark addresses that was found in the stock GM opti?

REDC4CORVETTE

:nopity Try this company http://www.delteq.com/products_opti.htm
this might be easier and longer lasting
than a dyna-spark?just my 02 :jester

corvette1271

...thanks....this does look promising.......

R23HTC

While that looks like an option it doesn't seem much different than the LTCC kit which you use a coil for EACH cylinder. The price of the two systems is about the same. This system cost MORE than a DynaSpark yet it does nothing to address some of the common problems I had with the opti yet still requires an opti to work. :rolleyes: If either of the two main problems I had with the GM opti (corrosion and bearing failure) were present on that system it would not work as well. :mad


[Modified by R94 LT 1, 8:57 AM 4/30/2004]

corvette1271

...i just spoke with them on the phone(delteq), and i guess the attractive thing
with this system is that (1) there is no requirement to tear the front of the engine down.......just disconnect the old optispark at the spark plug leads, even tho there is a connection back into the new sytem (2) so far this new system just keeps going.....except for plugs of course. (3) price at this point is $785........so right now i am interested, but there i am still researching this topic....

GlockLT4

it still uses the opti for timing... if your bearings go out in the opti (like usual) then you still have to replace the opti.