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Discussion Starter #1
I restored my 70 GTO, and pulled the matching numbers engine during the process. I didnt have money to have it built so I through a fresh poncho 350 in and been using it ever since. ( little over 2 years now.) Well Monday I finally broke down and took the 400 to the machine shop. I hadnt taken it in 2 years because I had to beat the pistons out of the block so I didn't have high hopes for it. Got the call this morning on my drive to work that it is going to need to be bored out to .060 and needs 3 sleeves because the rust in the cylinder pitted it that bad. :( $450 for the sleeves and then $80 to bore all 8 cylinders.

Well I thought on it some this afternoon and after calling Butler Performance for some opinon and advice. They advice against more than 1 sleeve per bank. And also .060 max bore. And I gotta say I agree. Who wants to put in 3 sleeves and then have to turn around and bore them to max bore?:confused

Looks like I am in the market to find another block, or do some work on the 350 I have now.. I would like to fit my #13 heads to the 350, but I gotta have the heads checked out also and see howbad the rust is in the valve seats on them now.

Your thoughts guys?
 

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Butler has a great reputation, and are highly thought of. That said, how about getting a second opinion, just to be sure? Jim at Central Virginia Machine would be my next call. I have heard of many sleeves going into an engine, but I am no machinist. Multiple sleeves might be a no-go on a race engine, but could possibly be do-able on a street build. If it were me, I would source another 400 block, age approximate, and build that. I would then oil, bag, and store the original #'s block and hold on to it. You never know. I would not spend the $$$ on the 350 engine. I would either run it as is, like you have been doing, or yank it for a replacement with a 400.
 

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:agree And keep in mind that Butler's recommendation probably didn't take into account the fact that it's the numbers-matching engine. "Normally" they'd be right - it's probably not worth the expense - but this isn't a "normal" case. Keeping that block just might be worth it.

Bear
 

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have a 70'400 virgin block at the machine shop cleaned checked and ready to bore. I may be selling, have to get up and grab it as i lost the block codes and need to get it back to the shop.
 

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Discussion Starter #5
I plan on keeping the block. Just think I might need to find another one to put into service now. I figured if the heads are shot also. Just for nostalgia, conversation piece in the garage. I Might bolt the heads on the block with the factory intake and paint it up like new and let her set in an engine stand in the garage.


Hard to believe someone let it end up like this. It has never been bored, and even had an erson cam in it when I pulled it apart. Sad, really. It was like someone robbed it for parts for some reason because it was missing lifters and pushrods. Or either someone started building it and never finished it. Probably sat in a field and got rained on for years and seized up.
 

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Discussion Starter #6
have a 70'400 virgin block at the machine shop cleaned checked and ready to bore. I may be selling, have to get up and grab it as i lost the block codes and need to get it back to the shop.
That would be nice but probably out of my budget. A friend called today said he was working at a guys house, and this guy said he used to race pontiacs back in the day and that he had a complete 400 with heads on it but it was wore out and would need a bore. Said he would take $100 for it. I think I need to go take a look at this asap.
 

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Know of a engine that had all 8 cylinders sleeved!! And then build to stock. Jumped in the GTO after couple years and drove all across the USA. Just saying its been done!!
 

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Discussion Starter #9
Know of a engine that had all 8 cylinders sleeved!! And then build to stock. Jumped in the GTO after couple years and drove all across the USA. Just saying its been done!!
Thought about that also. But at $100 per hole labor and $30 per sleeve. $1040 just to get the block usable I can't justify. Gonna get over and look at this $100 engine and see whats going on there.

I just hate that now I gotta go pay $100 to the machine shop for magnaflux and vatting the original block thats going to be a paper weight.
 

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It depends on what the car is, how rare, etc. I was speaking with Jim Wangers two years ago, and He informed me that an original (born with) engine adds about 10,000 dollars to the value of the car. In checking prices on restored and survivor cars, I have found that this is pretty accurate. $1040 is peanuts when you consider the whole equation, value wise.
 

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Discussion Starter #11
Its not peanuts to me! Its a little chunk! The car is nothing rare. Its just a 400/400 GTO. I didn't even paint it factory color because I intended on building the car I wanted. But I did want to atleast attempt to keep the original motor since that in itself seems to be a rarity.
When people say what motor is in it and I say "ah its just a little ol pontiac 350, but I have the numbers matching 400 Im going to put back in it". Saying the GTO has a 350 is a bit embarrassing (no offense to 350 owners). So Ive always had to throw that I have the original numbers 400, to make myself feel better I guess (probably seems lame but thats just me). When your driving a GTO and its got a 350 with only 7.5:1 compression 165hp, its just not living up to the expectations of a "muscle car" for me.

But another grand for an engine build is not peanuts for me, not right now anyhow. I got 2 teenage daughters! Maybe in a few years I can consider it.
 

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Okay....that clears a few things up. Oil and bag the original engine and build up a 400 for it, as time and $$$ allow. That's what I would do, anyhow.
 

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Orbit, I think you can safely go .090 over....this would be prefered, rather than sleeving. If you are gonna bore, you will need new pistons, Ross, will make .070, .090, etc....they may cost a bit, but you will have your original motor. Just sayin' :cheers Eric
 

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Discussion Starter #14
Orbit, I think you can safely go .090 over....this would be prefered, rather than sleeving. If you are gonna bore, you will need new pistons, Ross, will make .070, .090, etc....they may cost a bit, but you will have your original motor. Just sayin' :cheers Eric
Sorry, if I sound dumb LOL! Im not really familiar with the Pontiac as far as technical engine stuff. Like most Ive always had fords and chevys. I am aware of the differences of all three though. .060 is usually max on most of those, so I assumed it is on the Poncho also. I was concerned with the overheating issues that prone pontiacs anyhow, and didnt want to bore it out and increase that potential.

Your saying .060 is safe on these? So even max .090 might be ok?
 

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I also thought (and think) .060" over is about it on these blocks. Anybody running a .090" overbore with ok results??
I suspect that it would be much like other manufacturers, i.e.; .060" is the nominal "max". However, if the block is sonically tested to ensure wall thickness, larger bores are indeed possible.
 

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Jeff, I know it sounds scarey, but I know of several engines that have gone 090 over....the SONIC check is a must first !!!:party:Eric
 

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Yes, Eric, I have seen some flatheads go .120" over and more, even. But a Pontiac 400, I haven't seen. But I haven't seen everything, either.If it's an engine that had no core-shift and sonic tested fine, well, the proof is in the pudding. I would be tempted, at .090", to fill the lower portion of the block with block filler, though.....
 
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