He did a compression test today and indicated it was the ring in #7...bummer.

I'm guessing the motor is coming back out, correct?

This is my first significant break outside of a tranny and rear end, so is it even worth fixing?

 

It's up to you whether you want to fix it or not - I'm curious, I assumed you had stockish pistons in there, but you have a 355, so what parts are in there anyway?

Are you making 10 psi with no intercooling?

 

I have a front mount.

Mogul LT1 rebuild kit, so I assume there isn't anything too special about the pistons.

Stock rotating assembly with aftermarket valve springs, lifters, cam, rockers, push rods, 42lb injectors, and a 255lb Walboro.

The blower was bought (off the forum) while rebuilding the motor and the builder said he could lower the CR with a different head gasket to 9.5:1. Probably optimistic, but a suppose it is lower than the 10.5:1.

Unfortunately, me and the original builder have had a falling out over some things including the quality of work on my car, so who knows what is actually in there.

 

That's too bad. It's a lot of expense and hassle to do it twice. Maybe a piston upgrade will fix it if you are on a budget.

What was the tune? and how were you taking timing out? Maybe you got bad gas too, and that cursed you.

 

Ion/Madz28 did the tune and I asked him to be conservative as I thought it would get daily driven. Funny thing is, I was just cruising when it started to smoke and I hadn't been driving hard at all that morning.

I have a MSD 6Al but not the timing retard box, so I assume timing was taken out with the mail order tune.

My wideband never read more than 11.2...sometimes lower. That would be considered rich even for a FI car, correct?

It will be a lot of expense because my mechanical skills stop at changing the opti and doing a long tube install.

The motor does have to come out, correct?

Any recommendations on budget FI pistons for stock rods, heads, and stroke to achieve ~9-9.5:1 CR? I might as well fix it. The car is worth nothing with the motor shot...and it from what I'm seeing they aren't going for much even with the motor running great.

 

Too rich can detonate, too, but it probably wasn' that. It probably has to come out unless you pull the head and the pan and the cylinder is just fine, then you pull the rod/piston and put a replacement piston back in there - that is really difficult to do - I don't know if you can do that on thse cars...I'm not sure what pistons would be a good choice for you because you need to see how much yours weigh, see what forged ones are available, and determine if you need to rebalance your assembly for them - but it's something to think about

 

Thanks for your input.

Time to start researching!

 

Hope that helps some

 

Thanks for the input as well. I'm sure more questions will come in the next month.

The reason I did an email tune was because I couldn't find anybody local that will mess with the OBDI's anymore...even in Houston. I'm not kidding. Most of the race shops in my area seem like they won't even mess with the LS1s these days let alone my dinosaur. So unless you have a new vette or new camaro, they have a little interest.

 

I think it's hard for someone to have one of these OBD1 blower cars if they can't tune it or know someone that they trust to tune it when they make changes to the hardware. The other thing is that even if you tune it, different gas and weather can affect it, so you have to be aware of that. I think you should pull timing related to boost, and have it adjustable in case you get bad gas or you hear audible detonation. The other thing, is that you could inject some water/meth, but you would have to learn about it and get it right and include it in your tune, but it works well to keep Dr. Detonation away.