No, not a vette...but still an LT1. I'm hoping you folks can help me out with some advice. Here goes...

Background: Bought this car 12/2009 with fresh stock rebuild. Took the car to a local speed shop to install and tune an AI 200cc head/valvetrain pkg. I went with the 230/238 cam. Ignition components of unknown age, except the plugs are new.

Put about 100 miles on it after getting it back from the shop. No problems. Took the car out friday night for some cruising. It ran fine all night, probably put 100 miles on it. Topped off the tank with some Mobil premium and headed home. About 30 miles later, tooling along about 50 in 5th, the engine just cuts out. It's still running but no power and no response from the accelerator pedal and backfiring loudly out the exhaust. It does this for about 5-10 seconds while i'm downshifting to match speed & keep the engine from dying. Then it picks up and runs ok. About half a minute later, it does this again. It did this 5 or 6 times back-to-back like this. The last time it did it, there was a HUGE backfire, so big I could see the flash in my peripheral vision. After it recovered from that episode, it didn't do it any more all the way home. I took the long way and probably ran it 20 miles or so with no more problems.

After this, I moved and the car sat for a few weeks...

I drove the formula to my new house and it sat for a week. I fired it up one day and it idled fine but died after a 5-10 minutes. It fired right back up and I let it run for another minute and shut it down. I was going to move it one day about a week later and it wouldn't fire. So, I pushed it into the garage and pulled the opti over the course of a week (still getting settled in) and want to disassemble it. Then I noticed a date stamped on it...something like june 2007. It rotates ok but had some noticeable play in the shaft. I should probably core this one and get a new one. What do you guys say? I'm really sour on buying a stock opti...kinda leaning towards the dynaspark until I decide on which route to take with the ignition system. Good idea or bad?

The weep hole was dry but I'm considering a new water pump too. Might as well replace it while it's apart, right? Any recommendations on the pump?

 

I'd go with a delphi (stock replacement) opti, you can get them from thepartsladi on ebay at a good price. If you search opti threads on here a lot of people prefer the stock opti over the aftermarket ones, I'd also go with a stock replacement GM pump or convert to electric

 

what's the reasons behind going with a stock opti? it seems these things crap out at an abnormally high rate. Granted, the placement is the best but it seems there's more to it than that. I'm reading about how people say to loctite the rotor screws...seal the thing with silicone. Heck, I can't even figure out how to take apart the one I took off. It looks like the bolt heads holding it together are a half mm.

Where can I source a stock replacement gm pump? Are talking about from a dealer or advance/o'reilly's?

 

I think the stock GM pump on the LT1s was ACDelco there should be a bunch of places you can get it from other than the dealer. As for the opti, you can do a search and find a lot of threads on the aftermarket ones and delphi units. The delphi units seem to have the best track record from what I've read