Hey everyone so I bought a 95 lt1...drove it for a week and it leaves me on the side if the rd get it home and the rotor pushed against the cap melted it and broke.put a new AC delco on that lasted about a month same thing happen so I dropped the 500 on an msd put it on lasted about two months.what its going on? Anyone have this problem? Tried pushing the cam in and out and I can't bug it. That doesn't mean its not moving at high rpm but my boss said there's a plate at the end of it that keeps it from moving?ive never been inside an lt1 so I don't know..

 

Are there any mods? Constantly eating up rotors would lead me to believe that the dowel pin is too long (common with many off-the-shelf cams).

 

Not really sure about internals guy I bought it off said there's a cam and the heads look after market has a bbk throttle body hyper tech chip under drive harmonic balancer and the block is freshly painted with all new gaskets so who knows what's done to it..the bearings in the distributor I bought it with were shot so Idk I've only put 2k on this car and this will bee the third distributor unless msd warranties it...now How you said the dowel pin is to long? Wouldn't the distributor have trouble going on? Cuz it's went together pretty smooth so far

 

Very much sounds like the cam dowel pin is too long. If that is the case, every opti you put in it will die in a short time (in the fashion you describe).

 

If the pin is slightly too long (maybe .020" is all it takes) you wouldn't know it. If it bottoms out in the drive then the bolts that pull the opti on will put pressure on it. It has to be the correct length.

 

So how do I no if it's the problem? Being to long. Is there a spec? And can I just cut it our should I get a new doll

 

Remove the cam gear and measure the pin length from the cam face. Should be around ~.600". You can either tap it in or cut it.

 

What a night mare

 

It's not that hard to remove the optispark.

 

Ya I no I've had it apart five times and I took the air pollution **** off so I can have it apart in about half hour but that gear is the timing chain gear so I have to remove the cover and chain..question the two lines coming off the distributor are they breathers or does it have to be connected to the air inlet tube and the other on the manifold? Also if that dowel pin is sticking out to far that would make the bearing on the distributor go bad and make the rotor hit the cap correct? I have not taken the msd I put on apart yet but I no IRS failed cuz the last three times the opti has gone bad it back fires for a few seconds than stalls and won't start again and every time I take it apart the rotor is melted or broken

 

Its*.. Ive became disgusted with this car and haven't had much time to get it apart but I know now its more than just the distributor being this is a continuing problem

 

Would seem to me if the pin were too long, the distributor should be bottoming out on the pin before it gets flat against the block. So if that were the case, the person putting it on SHOULD have noticed that. Meaning, they would be relying on the bolts to pull it flat against the block. So????????

The only way for the pin to be to long, the cam would have to have been changed. So if you don't know for sure, check the markings on the end of the cam.

 

4th Gen LT1 F-body Cam Install

 

Could place some silly puddy in the slot the pin should fit in on the back of the opti, install it and tighten bolts to spec then remove it and see the impression of the fowl pin in the putty to get an idea of how much space you have before it's bottoming out into the back of the opti. May need to put a little flower or talcum powder on the dowl so it doesn't stick to the putty.
Can then use some thin washers as shims under the opti to shim it out some.
The dowl only needs to contact the opti surface to about half the depth possible before it bottoms out, thus ensuring it's not pushing forward enough during heavy acceleration to bottom out. Yes there is a cam retainer plate behind the cam gear that keeps the cam from pushing forward, it could be worn some.

 

Probably not a good idea to shim it out since I believe the timing cover seal rides against the opti flange. Would probably leak.