I am a little furious at the moment and have been for awhile over a matter I had dealing with the machinist. It was my intentions to have my block splayed to four bolt, align bored, honed and square decked on the crank centerline to a height of 9.010 with a .030 overbore.

I was VERY clear on what I wanted to do and how I wanted it done. You would think that if it was not possible for him to do he would have told me so.Fast forward to my problem. I get the block back and it has been overbored .030, but thats it! I took it to another machinist and he now says that it cannot be splayed unless I overbore .040 that the caps distort the block and they should be in place when then bore was done. I already have my pistons and rotating assembly everything ready to roll, now this.

So I would like any inputs or suggestions from those of which know best. I would really like to splay the block I am just torn on my decisions now. Thanks in advance.

Jack

 

From what I've heard, a strong 2 bolt may be just as good as a 4 bolt splay.

 

Get main studs and call it a day. Just hope your machinist didn't dick up anything else.

 

I have the main studs (ARP) already. I would like the added insurance of the 4 bolts if it is still possible without having to bore further, I realise this may be out of reach now without acquiring a new block. Thanks for the input so far, I know we have a few machinists as members here.

 

Im not sure about having to punch it out another .10 but if you did a .40 over isnt going to hurt anything, your going to have a bit larger displacement.

If you wanted 4 bolts then get it done, your not going to get the strenght of a splayed cap and bolts with a 2 bolt mains.

 

I realise it won't hurt anything other than the fact that I already have pistons that are .030 and for the record it is going to be a big hp 355 so I am not comforted with the fact that I am stuck with two vs four right now lol.

As I stated in my first post the machining was critical to my build. I am an absolute perfectionist when it comes to the details and thats already been boogered up to be nice about it. Although I have 17 years racing experience( engine building) I have ALWAYS outsourced my machine work and never had a problem until now. I had specified everytig that I wanted and even had it on paper for him to go by. The block was in great shape and needed only a good hone but I punched it to .030 and wanted the mains and cam journals align bored then honed and the square decked from centers of mains with a deck height of 9.010.

 

how much rpm are you going to turn?

I turned my 2 bolt 8500 a few times and It didn't fly apart....YET

 

Well thats a loaded question lol. I KNOW that a 2 bolt is capable of doing some amazing jobs, but I cannot afford to do this again anytime soon. Money isn't the factor my health is. So to answer that as much as my neck and back can take lol, as far as components its fully 4340 crank, hbeams and rated for 800hp front to back of car. It will NEVER see that but I know that I will have 500+ on the motor alone and looking at about 430-450 rwhp true N/A.

 

I did kinda same thing. First I bought main studs and in the studs kit it said they reccomended line bore, So I said if i'm going to line bore I might as well go splayed. I didnt have to change anything. I don't really know what it would have to do with cylinder bore.

 

It will distort the bores to install the new caps. A lot. The new machinist is right about how it should be done. Sorry.

Rich

 

rskrause is again correct. Installing splayed caps does reshaped the cylinder bores. Re-truing the bore size after cap installation is important. Further, 4-bolt caps, either a Corvette block or splayed are more than just a "good idea" if you're serious about a good LT1. Taking the 2-bolt main caps off an LT1 that has seen 7000+ RPMs on a regular basis is a real eye-opening experience. Stock caps, even with studs, move around enough to leave visible traces on the caps and block. How far can it be from disaster?

It appears that you're caught between a rock and a hard spot. Which is the least painful, starting over with a different block or buying a new set of pistons? Who is the most flexible to deal with, the company you bought the pistons from or the machine shop that neglected to install the caps as you specified? It's time for some hard choices.

 

What was the machine shop's response to screwing up the job? It seems they would have some sort of liability.

 

yeah they owe you a set of pistons...:lol;

I plan to pull mine apart and do the main caps this winter. I was in a rush and ran out of money so I left mine. I need some dome pistons anyway

 

Unfortunately my dilemna with that machine shop is absolute. It cost me a long friendship. I guess I will use my other block and start fresh with it. Thanks for the advice. I kinda knew it was the right answer but holding on to the chance it could be done.

 

You could buy a girdle, that would add some added proctection. http://www.prwonlinestore.com/index....ROD&ProdID=163