Here's the latest update on the what's happening with the engine.

Before I insisted the engine builder rebuild the motor, I decided to dyno it to see the horsepower and air/fuel ratios; and this explained a lot...

At idle and cruising speed, air/fuel ratio was almost 10 to 1. At wide open throttle, it was 16 to 1. The engine made little power all through the rpm range and maxed out 390 to the wheel at 7100 rpm, and 408 at the same rpm with open headers. Max torque at any point never exceeded 354 to the wheel; hardly the performance you'd expect from a max effort solid roller 388 cubic inch stroker.

On all runs, the exhaust poured out thick black smoke that literally filled the shop and made everyone choke. Also, on EVERY run, the engine shut off at precisely 118 mph for about a second, and then recovered and pulled to a higher mile per hour!? I was told by a GM technician that the speed limiter may not have been fully removed from the computer program in the mail order tune.

Now for the rebuild...


Upon engine removal, the motor was covered in oil. The intake was not sealed properly, and was leaking profusely from the front and a little on the sides. The opti-spark and timing cover were saturated with oil and grease. Many of the head studs appeared to be covered in grease/oil while the areas around them were completely clean??

Upon disassembly, the builder discovered a few issues. The cylinder walls were washed badly. He noted that even if the motor was tuned perfectly at this point, the cylinder walls and rings would never recover; not a big deal now as the engine is being rebuilt. The rod bearings showed signs of detonation, and the builder said it was not due to high compression (11.1 to 1 per engine builder), but rather a rich tune that caused the rings to wash and allowed the oil to get past them; thus killing the octane effect.

He also said the computer tune may not have been totally off, and suggested the possibility of a vacuum leak, which was previously looked for by a GM tech and never found, but still a possibility. Interestingly, two intake runners were sucking in oil from the lifter valley itself. I'm not sure if this would qualify as a vacuum leak or throw air/fuel ratios off, but intake runners sucking oil would definately be destructive in and of itself. Obviously, great care will taken when installing the intake and gaskets when the motor is re-assembled.

As to the valve train issue, he said the rockers and pushrods were to blame for initial failures. He said there weren't any metal shaving in the bottom of the motor or in the bearings, but that there were metal shaving in and around the heads. The combustion chambers were acutally wet and full of grease and carbon build up, and the pistons were caked with carbon build up. The engine has less a thousand miles on it, but considering all the issues, it's no surprise to see that. Both O2 sensors were caked with carbon and slightly melted/deformed from their normal upright shape.

The new engine will have a smaller hydraulic roller and all new ignition hardware such as plugs, wires, and opti-spark. The tune will also be addressed before the motor is fired; and will be started and ran on a dyno to make sure it's where it should be.

Thanks to everyone who offered advice in this thread.

 

Who tuned it?

I would say try to get a dyno tune this time. Glad you are getting it together...I know how frustrating it can be.

The inake being sucked in will cause a bad vacumm leak, could possibly lose all your vacumm and makes the regulator go rich...so rich the pcm was out of its boundries to correct itself? I don't know for sure but its a possiblity

 

The computer was tuned by Ed Wright. While he told me it would be close, I think it's safe to say that a vacuum leak was causing the computer to run rich/lean. I'm going to call him and see what he thinks about air/fuel ratios, and also ask him about the car cutting out at 118 miles per hour. I told Ed initially that I was sending him a brand new computer, and did not get it flashed to my car before sending to him. He said he could still tune it, and this may explain why the car was cutting out at 118, as it's a factory speed limiter for some computers, but not for my car as it came factory with Z-Rated tires.

I talked with him several times when I originally sent him my computer and he was helpful and knowledgeable about my set up. I also followed his advice and ran a factory stock mass air flow instead of the ported stock one I had before with my MTI tune. I can get free re-tunes on that computer, so I'll send it to him again to make changes for the new cam, and address any other issues he wishes to change. With that said, I have no doubt that he's a good tuner, I just think that my engine is to blame in this particular case.



Just to be safe, I also have a second computer sent to another tuner (Jeff Creech, of Carolina Auto Masters). I really want to make sure everthing goes correctly the second time around.

 

Continuing to throw random changes at it without understanding the problem...

 

The pistons will remain, it appears that they'll be fine to use again.

The solid cam was obviously not set up correctly, or not set up with the proper hardware in first place. I don't consider switching to a Hydraulic Roller a "random change," especially for the street. As other members have stated, even if a solid cam is set up correctly, it's less than practical and compromises reliability over a hydraulic cam.

My instructions from the beginning is that my car was to be streetable and reliable enough to be a daily driver.

 

Is everything fixed now? ever figure out the problem?

 

no sign on since jan

 

His engine has been re-built and back to the guy installing it, but they've still discovered stuff that just isn't right. I'll let him post details. The guy who built it is touted in a monthly automotive Particular Hobbyist Report as a bad-*** engine builder, but I wouldn't take my Briggs and Stratton to him after seeing the work done to this engine - twice.

 

Did I not tell the guy to get his engine the hell outta that guy's hands?? Why does he feel he needs to give this hack opportunity after opportunity to redeem himself when its obvious that the mechanic wouldn't know HOW to redeem himself if his life depended on it??? I hope it all works out for the guy and the issues with his motor get worked out.

 

B/C the engine builder is well know and builds alot of championship winning cars.....builds 200+ mph race engine daily.

I think they just saw it as a "street engine" and just threw it together...possibly one of the lower people on the totum pole built it?

I just wanted to know what ever happened....

 

I don't care how many 200+ mph race motors he builds, if i'm paying my hard earned cash with him, I expect an itemized list of whats going into my motor. If there's a problem with the motor, I expect the builder to actually go through the motor and actually figure out the problem and not just randomly throw parts in it guessing at what the problem "could" be. An engine builder that produces championship winning, 200+ mph motors should know that it's just not smart to try to daily drive a solid roller motor. It appears that there are STILL issues with this motor. If he stays with this hack and spends more money with him only to deal with more issues, then I can't feel sorry for him any more. JMHO

 

I wish I had seen this thread earlier....I know some better So Cal shops where this stuff doesn't happen.

 

I just found this site and this was the first thread I read on it...

This after I just placed the top end together on my first LT1 rebuild.

I don't sleep, I'm up to two packs a day... Then I read this trainwreck.

If this is the wrong venue I apologize in advance, BUT:

Well I think I'll run over to the LT1 section. If you guys would ll over there and take a look at what I've got, I'd appreciate it.

I'll label the thread: Stock LT1 Rebuild

I hope this guy gets this worked out.

I can't imagine having this level of patients with this guy. I'm only down $3500 and it's killing me...

 

I finally got the motor back in late April and I've been waiting for a friend of mine to go through and inspect everything before it goes back in the car.

Just for the record, I let this engine builder rebuild it because he incurred all costs and wanted a chance to make it right; and I admire and respect him for that. At the same time, I think it's more than fair considering the results and the amount of money paid for his "expertise."

I was told it had bent valves and pushrods upon disassembly. The engine builder had no explaination of how that happened.

When I picked up the completed long block and took it to the guy that's going to inspect the rebuild work, he alreadly noticed problems with the valvetrain!

Notably, the rockers are not aligned properly. Apparently, the rockers need adjustable guide plates? Some of the roller tips are not centered on top of the valvestems. When it was pointed out to me it was grossly apparent. They're cross eyed and only touch the outer most edge of the valvestem! Not all valves were like this as some were more centered than others. The guy inspecting this also suspects that there are other problems with the rebuild such as insufficient valve clearance for the pistons; hence the repeated failures of bent and broken rockers, bent pushrods, bent valves, and the thickest head gaskets I've EVER SEEN on an engine! BTW-the head gaskets now are even thicker than the last ones!

One of the heads will be pulled off in the next few days and checked to see if they have ample clearance. I was told before by the engine builder that the PTV clearance was "more than enough" when I asked him if that was a possible factor in bending push rods. If the clearance is off, the motor will have to be disassembled to have the pistons clearanced or replaced. These are "custom JE nitrous pistons" ordered by the engine builder himself! I did not order "any" of these parts myself. There should be no reason for the PTV clearance to be off, unless it was overlooked the first time. And if that's the case, they shouldn't be in there now!

I'll stop speculating and wait for the facts...

As soon as I know the results, or any other information on this train wreck I'll post it here. Hopefully this headache will be over soon, 'cause I'm all out of aspirin.

 

I can't believe the pains you are going through to have a properly built engine. I feel for you. By the way, EXCEDRIN "the head ache medicine". Take as many as you need until you burn a hole in your stomach, then back off a couple a day. Seriously though, I hope that in the end she runs like a raped ape. I think you deserve at least that, for all you have put up with.