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TheBandit 09-04-2012 05:58 PM


I talked to the machine shop today and not only is my block not ready, it's SCRAP METAL! :pissed: Apparently the cutting tool came loose while they were boring the cylinders and took a deep cut out of the cylinder wall. Damn it! I could hardly speak to the guy as he gave me the bad news. He said they found a replacement block and started machining it today, but had not confirmed if it was a Gen IV block, so I don't know if it will even work for me AND I have no idea what the history is in terms of mileage etc.

What do people normally do in these situations??? What should I be asking for from the shop?

I am too angry to think clearly.

SomeGuyFromOlympia 09-04-2012 06:15 PM

to make it right it needs to be replaces with what you have or something better

but thats my opinion

sure brings the suck though

JaysinSpaceman 09-04-2012 07:53 PM


First, sorry to hear the news. I really don't know how some shops hire their staff but it must go something like "Hi, do you have a pulse? You're hired!".

I would tell them you will not accept any replacement block that is not the same as your current block (a gen IV) and that it must machine up at the same specs (ie., .020" .030" .040" overbore etc...) as the current block would have cleaned up at and not require any extra machine work then your block would have required (ie., if your block didn't need a line hone then the replacement shouldn't either). And lastly I would expect them to make it right on the final price for delaying the work that was promised (I wouldn't bring this up until the work is done). Then once you receive the parts I would borrow the appropriate measuring tools and ensure that the machine work was done correctly. When a job goes south, as this one has, some people will recoup their loses by doing a quick and dirty job and getting it the hell out of their shop, I have seen it first hand.

Good luck and again sorry,

TheBandit 09-04-2012 11:26 PM

After settling down a bit, I called the shop and talked to them some more about the issue. I expressed my frustration with the long delays in getting this done and they were appologetic. After some discussion, they determined the block they had to replace it with was not a Gen IV block so now they are hunting for another. I was surpised they didn't know the difference without me telling them, but maybe I was just talking to the wrong guy. Apparently among machine shops they often exchange rebuildable cores in these situations, so that is how they hope to find a replacement. I told them I would also consider aluminum Gen IV blocks like an LS2 or L76 if they come across one. They asked if that is what I would prefer because they would like to make things right with me and I said yes, I think that would be better. We ended the conversation with a promise to call back when they find something so we can figure out how I want to move forward.

Overall I'd say they are doing OK in responding to the problem so far, but I will probably be on edge for a while until I see a finished shortblock on the engine stand. I'll post more as things develop. Thanks for the continued advice.

Graham08 09-05-2012 09:36 AM

Sorry to hear that bad news, Clint. Hopefully they come through with a good aluminum block so you will be better off than where you started.

I am not looking forward to finding a good machine shop to do my engine work. There are getting to be fewer and fewer of them around since modern engines go 100,000+ miles without any work other than changing the oil.

TheBandit 09-06-2012 03:28 PM

I got word today that they found a Gen IV 6.0 iron block (most certainly an LY6 or L96 since all others would be 4.8/5.3 or aluminum) and expect to have it in their shop tomorrow. They said if it checks out they could have it ready by Monday. I guess we'll see.

Graham, I am with you on the difficulty finding a shop. I did a lot of calling around before I landed with this place. Everyone's experience was positive. I hate being the exception!

reaper969x 09-18-2012 09:05 PM

Hard finding a GOOD machine shop these days.

TheBandit 09-19-2012 06:29 PM


Originally Posted by TheBandit (Post 122693)
I got word today that they found a Gen IV 6.0 iron block (most certainly an LY6 or L96 since all others would be 4.8/5.3 or aluminum) and expect to have it in their shop tomorrow. They said if it checks out they could have it ready by Monday. I guess we'll see.

Well that block showed up Monday, but had a crack between the main webs. So disappointing. I have been calling the shop daily to keep a bug in their ear. They are nice people and I understand their situation, but from my perspective this has been a very bad experience. I dropped my block off at QMP Racing 7/13. They received all the parts by 8/6. The block didn't get on the boring machine until 9/1 and I had to call them on 9/4 to find out they had damaged it. Now we're in a situation where finding a replacement isn't going to be easy nor expedient. I would argue for a new replacement block, but it turns out you can't buy a bare LY6/L96 block from GM - they only sell it as a longblock. The only new bare Gen IV blocks available are the LS2/L76, LS3/L99/L92, and the LSX. An LS2 block is about $1,200 new. Of course I'd be happy with that, but they aren't too hot with that idea.

I got an email today from them and while they are still looking for a replacement block, they offered to sleeve my block and do all the block machine work free of charge, but would still charge for the crank polish and balancing. I have been doing some research on sleeving blocks and while it gives me some heartburn, it would save me a big chunk of money. I am going to call and see what they can tell me about the process and reliability of the repair. From what I've read the most important things are to get the right interference fit and either machine a step at the bottom of the bore or use a flanged sleeve to prevent it from shifting. Other than that I have no idea how reliable that kind of repair is or if this offer is worth considering. Thoughts?

bru21 09-19-2012 10:26 PM

I think its an integral part of the motor and a massive PITA to swap out later. I would chase down a block yourself and invoice it to them. Maybe give them 7 days or explain this is what you will do. It will be in the back of your mind every time you give it some berry's otherwise!

jwilson 09-20-2012 11:53 AM

I would NOT call them to get the explanation of the process/reliability on sleeving. Of course they are going to make it all sound good. I would find another shop to call for those details.

TheBandit 09-21-2012 11:26 AM

I spoke to the shop a bit more yesterday to get details. They leave a step at the bottom of the cylinder to retain the sleeve. The block is honed for a smooth interference fit to optimize heat transfer. They use dry ice to shrink the sleeve prior to install. No sealant / locking compounds are used to prevent loss of heat transfer. In their opinion the repair is as reliable as the original block when done properly.

I also contacted a different machine shop to get their opinion, Steve @ Race Engine Development in Oceanside. He echoed this is not an uncommon repair and when done properly is as reliable as the original block. The important thing to note is that if the block is cracked it will likely leak. In my case, the block is not cracked and the damage did not break a water jacket. Steve was very helpful and I greatly appreciate his advice.

QMP has been honest with me about what happened. If they were dishonest I think they would have just sleeved it without telling me what happened since the sleeve will not be easy to see once the fix is done. They have also offered to work with me to make things right. At this point I am leaning toward taking their offer and having them proceed with the sleeve.

CarterKraft 09-21-2012 12:17 PM

I misread your original post and thought the mains where dinged...

While I wouldn't exactly be tickled that it happened I would gladly take a sleeved block and free machine work. I would have zero concerns with the sleeved repair in the future (if done correctly.

Roll on 18 wheeler I am ready for some burnouts.

JaysinSpaceman 09-21-2012 07:01 PM


While a sleeved block is not what was in the original plan, I don't really see any problem with it. I have personally installed two sleeves in SBC's (I did all the machine work while taking an engine machine class, for 6 semesters:biggrin:) and both motors still run just fine, been about 6 years now and one of them sees a lot of abuse by a lead foot. If they are willing to try to turn this bad situation into something better by sleeving your block and and giving you free machine work then I say go for it. There is nothing wrong with a sleeved block if done right.


CarterKraft 09-21-2012 07:52 PM

try Tums for the heartburn....

Sleeves are cake, think about it extremely high horsepower engines (think Top Fuel) are sleeved, they don't care.

TheBandit 09-22-2012 12:26 AM

Thanks guys. It makes me feel better about my decision to hear your thoughts. I talked to the shop today and gave them the go-ahead. I asked them to take some photos for me in process, so hopefully I can get those later to share.

Okay on to other things. If you remember a while back I mocked up the accessories:


Notice how low the AC bracket sits where the tensioner attaches at the bottom. I unfortunately didn't take any photos, but when I was mocking things up I did a test fit of the sway bar and it interfered with that part of the bracket. To remedy, I through some washers under the sway bar mount to bring it down and was able to get enough clearance. So now I am following up with a more permanent solution - some aluminum spacers. I made these out of 1/2" aluminum (nevermind the temporary hardware - I need to get some socket cap screws to fit these properly)


With the spacers, here is where the swaybar sits relative to the notches in the frame:



It's hard to see, but there is still a small clearance between the bottom of the bar and the middle of the frame. I have a feeling the bar may rub here when the bushings distort under load, but not enough to hurt anything.


Now doing this is not without penalty of course. There is a 1/2" reduction in clearance between the sway bar mounts and the lower control arm. To see if it limited up travel, I tried jacking the car up by the control arm. Because there is little weight on the front of the car, the bump stop hardly compressed.


So next I removed the bumpstop and jacked the arm up until it made contact. Not surprisingly, the lower control arm hit the sway bar bracket.


In this position I measured about 1/2" of gap where the bump stop goes.


Here is a tape-measure shot of the factory-style bumpstops I currently have. The overall height is about 1-1/2" and the full width portion is about 5/8". I am not sure how much this will compress under load, but I have a feeling it may be close. Anyone have any experience in this regard to tell me about how much bumpstop compression I should expect?


Thanks for any thoughts/feedback.

PDANKracing 09-22-2012 01:16 PM

You can figure out the compression by putting it in a vice, just drill a hole in a piece of flat bar to go over the stud.

My guess is you'll be fine, unless you drive like one of the Duke boys.

JaysinSpaceman 09-23-2012 12:04 PM

I agree with Pete I don't think you will have a problem. The bottom part of that mount isn't going to compress easily and you could simply shorten bump travel just a hair with an 1/8" spacer under the bump stop.


TheBandit 09-27-2012 09:16 PM

Thanks guys. I think I will run it as is and see how things go. I hate to lose any bump travel since it will be lowered some already, but if it does hit I can shim the bumpstop and potentially increase ride height if it's unmanageable.

Got a call from the machine shop today. The block is finished. I couldn't pick it up today but will try tomorrow. They checked all the bearing clearances for me and came up with:

Mains: 0.0011in (Clevite P spec 0.0002-0.0018)
Rods: 0.0021in (Clevite P spec 0.0012-0.0037)

Both are within Clevite specifications, but the mains sure seem tight by performance standards. This is with stock style (p-series) Clevite bearings. I can go to a performance bearing (h-series) which is available in 0.001 increments if I want to increase clearance. I'm not sure what to do yet. I was leaning toward the p bearings because I've heard it wears better, but it isn't available over-sized and I think I may want to shoot for more clearance. Any thoughts?

TheBandit 09-28-2012 12:58 AM

I edited my previous post after finding the Clevite specified bearing clearances. It looks like I am pretty well in the middle of what they recommend. Sure seems very tight - I'll have to do some poking around.

Graham08 09-28-2012 07:13 AM

You might want to take a look on the forums at www.speedtalk.com. There are a bunch of sharp guys over there, and I know this has been discussed quite a bit.

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