vented or unvented optispark?
02-27-2004, 01:42 AM
#1
Registered User
Thread Starter
Join Date: Feb 2003
Location: CENTRAL CALIFORNIA
Posts: 685
vented or unvented optispark?
i'm trying to find out which one i have i think i have a vented optispark on my 94 camaro, i replaced it 3 years ago and didnt know anything about cars but now i'm thinking its a vented and i have no vacumm harness? whats the best way to tell?
02-27-2004, 05:21 PM
#6
Registered User
Join Date: Apr 2000
Location: Austin, TX or Texas State University at San Marcos
Posts: 1,070
Originally posted by Hawk350
Is this conversion a MUST when doing heads and cam? And if it is...why?
Is this conversion a MUST when doing heads and cam? And if it is...why?
02-27-2004, 05:28 PM
#7
Registered User
Join Date: Nov 2003
Posts: 65
I wasn't going to change mine either when doing a cam install untill I learned that over 6000 rpm you need a heavier duty timing chain and I didn't want an electric water pump so the only option was to go to the vented opti so I could run a lt4 ex duty timing set.
02-27-2004, 06:46 PM
#8
Registered User
Join Date: Feb 2001
Location: Charleston, WV, U.S.
Posts: 1,084
rkussy, can you explain a little further? I am in the middle of a rebuild so I'm debating over what to do with timing chain, opti, waterpump. I think I'd like a Meziere, why don't you want one? If I'm to replace my opti, can I just buy a 95-97 (cheaper) or do I have to get an older one and modify it to be vented? What timing chains fit with what opti's and waterpumps? I need to upgrade to a better chain too but would rather opt for something cheaper than the extreme duty if possible. If I go the Meziere route how about the Lunati timing set? ($109.00). The extreme duty is made for stock waterpump .....I see now looking in this Jegs mag ....
02-28-2004, 01:27 AM
#9
Registered User
Thread Starter
Join Date: Feb 2003
Location: CENTRAL CALIFORNIA
Posts: 685
optispark
i have an aftermarket opti i think i forgot to mention it does have a tube in the bottom like kind of the one from where the coil hooks up. and theres no vacum hoses attached to it.
question! could you put a vented opti on a 94 camaro alone no other modification ???
question! could you put a vented opti on a 94 camaro alone no other modification ???
02-28-2004, 09:21 AM
#13
Registered User
Join Date: Nov 2003
Posts: 65
The reason I did't go with the electric water pump was after reading so many posts about life of the pump worries about it failing and not being aware it failed I decided I could deal with a little less hp and possible leaks to have a pump I could rely on. The Lunati chain is a link type just like the stock one so there doesn't seem to be any advantage to that. The ex duty is a little pricey but with 6400 rpm shifts it is needed. If you are willing to use the electric water pump then you can use a true double roller for less cost. Your own preference.
02-28-2004, 10:10 AM
#14
Registered User
Join Date: Apr 2000
Location: Victoria, BC, Canada
Posts: 510
Originally posted by canbaufo
rkussy, can you explain a little further? I am in the middle of a rebuild so I'm debating over what to do with timing chain, opti, waterpump. I think I'd like a Meziere, why don't you want one? If I'm to replace my opti, can I just buy a 95-97 (cheaper) or do I have to get an older one and modify it to be vented? What timing chains fit with what opti's and waterpumps? I need to upgrade to a better chain too but would rather opt for something cheaper than the extreme duty if possible. If I go the Meziere route how about the Lunati timing set? ($109.00). The extreme duty is made for stock waterpump .....I see now looking in this Jegs mag ....
rkussy, can you explain a little further? I am in the middle of a rebuild so I'm debating over what to do with timing chain, opti, waterpump. I think I'd like a Meziere, why don't you want one? If I'm to replace my opti, can I just buy a 95-97 (cheaper) or do I have to get an older one and modify it to be vented? What timing chains fit with what opti's and waterpumps? I need to upgrade to a better chain too but would rather opt for something cheaper than the extreme duty if possible. If I go the Meziere route how about the Lunati timing set? ($109.00). The extreme duty is made for stock waterpump .....I see now looking in this Jegs mag ....
The '94 opti can only be used with the stock "stamped" chain
to convert you need a bunch of parts listed here
http://para.noid.org/~muttvette/opti.html
the benefit of converting is to be able to use a better timing chain
I'm going to an agressive cam heads combo and wanted a better timing chains and have done the opti conversion so I could install ED timing chain.
if you want a double roller and/or cloyes set you need to have an electric water pump.
no major cost benefit as the elect water pump plus the cheaper chains is close in cost to the ED set. basically a function of the age of your existing water pump. i just replaced mine so I did not change it.
As far as Hp savings - I can not believe the small WP sproket is a huge drain of HP
The problem with the elec pump is that they may leak and fail without warning - but you can putin a warning light in case of failure and a proper install won't leak.
to convert you need to change the timing cover - do not get a '97 as it has the crank sensor - the '95 cover is best ~$60 new
opti is ~$200.
I sold my vented opti for $175 so the cost of conversion was not to bad (but my opti had low miles on it)
email me if you want more info
02-28-2004, 11:48 AM
#15
Registered User
Join Date: Aug 2000
Location: Houston, Tx USA
Posts: 1,903
if you are thinking of doing an electric waterpump know that it does out flow a mechanical one during idle.. but at WOT the crank driven out flows it.. I did the mez and was having horrid heating issues because I would drive at sustained high speeds and high RPMs.. I wasnt getting the flow I needed..
and an vented is best as far as optis.. You dont want to have to replace it over and over..
and an vented is best as far as optis.. You dont want to have to replace it over and over..