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Can someone please guide the novice regarding an engine restoration. I have received quotes for engine rebuilds but not being an expert, I'm unsure of what questions to ask in order to insure that the mechanic actually restores my engine to it's original glory, while being able to use unleaded gas, versus rebuilds my engine. I do not want to do anything drastic or custom. Is there a publication someone can recommend regarding questions to ask? What is a reasonable price range for such a job? Other than asking for references, is there anyway to insure the mechanic performed the work requested? Is there a test that a restored engine should undergo to prove the work was done correctly(Dyno)? I've been too disappointed with previous restorations by not establishing mutually agreed upon expectations. I'd like to avoid that mistake with my engine job. Please help. Thanx. I live in Westchester County, NY.
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Re: 327/365HP engine restoration-vs-rebuild
Most "engine rebuilders" deck the block, mill the heads, and grind the crank, because "we do them all like that".
When "restoring" an engine, you DO NOT want to remove metal unless ABSOLUTELY necessary. This is particularly critical regarding block decking as milling the deck will wipe out the OE ID stampings and the original broach marks, which are straight, not circular like most field milling equipment. If your crank is ground it will eliminate the Tufftride surface hardeng and reduce durability.
You do not need to install "hard valve seats" and you want to establish a static compression ratio of about 10.5:1. This can be achieved by assembling the engine with compositon head gaskets if the block has typical deck height.
In order to accomplish this you must measure the piston to deck clearance prior to pulling the pistons. This will tell you if the decks are parallel to the crankshaft axis (usually) and whether the height is different side to side (usually is). With this information you can use proposed head gasket thicknesses to compute the CR until you find a thickness that gives the number you are looking for.
I recommend all OE or OE equivalent parts for the job, except the connecting rods. They must be replaced since the early 327 rods are weak. For mechanical lifter engines I recommend Crower Sportsman. I also recommend using the GM service replacement cam, which is the LT-1 cam.
Suggest you research the archives since there is considerable discussion on the subject.
You need to understand "engine restoration" versus "engine rebuilding" and have a machine shop who understands the difference too, and you must manage your project by directing the machine shop to only perform those machining operations that you specify.
If they give you the "we do them all like that" routine, keep looking for an acceptable shop.
Duke -
Re: 327/365HP engine restoration-vs-rebuild
Peter,
I agree with most of what Duke had to say about your engine rebuild. Most machine shops feel it's necessary to sell you much more than you need as it pays for all of the expensive equipment that they have. However, many of these operations are not needed and definitely not wanted. As Duke mentioned, it's extremely important that they know this block must not be decked. If they push the issue, look for another machinist. Another procedure you definitely want to avoide, if at all possible, is align boring or honing the main bearing bores. Again, many engine builders will try to sell this operation even if not needed. Very dangerous if not done properly.
Several prcedures will depend on your ultimate use of the car but cylinder wall finish is very important in either case. I would never let an engine builder bore/hone the cylinders in any engine unless he has an automatic feed precision hone. Cyl wall surface and todays rings make a lot of difference.
If you plan on occasional show and moderate driving, I would not install new hard valve seats. I would also go with the original 11.0-1 compression ratio and definitely use the correct original 3849346 cam, not the LT-1. Absolutely no point in changing the cam unless it's worn and if so, a correct replacement is available from several cam mfg's.
If you are going to prepare the car for show and you want to maintain it's originality, I would definitely use the correct steel head gaskets. I believe this is, or at least should be, a judged item. 11.0-1 works well with no problems on todays fuel.
You may also want to take several pictures of the engine after it's been cleaned enough to reveal some of the factory applied hand written codes before it goes to the machine shop. If you are headed for an accurate restoration, these pic's will help later when reassembling/restoring.
Another thing I would do for sure is a complete engine/clutch/flywheel/dampner balance, especially if you have to replace rods or pistons.
MichaelComment
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Re: 327/365HP engine restoration-vs-rebuild
In addition to the excellent advise Duke provided, ask a number (as many as you have patience to ask) of local people for recommendations.
Go to hotrod cruises and ask them who is good.
Ask local NCRS people who is good and will do it like you want.
Find a local restoration shop and ask them.
The reason I say local is, it will be hard to manage the job long distance.
When you get some consensus, go to that machine shop and discuss what you want and note their response.
When you decide on a shop give them instructions in writing so there is no question of who said what.
I know a guy who specifically told a shop "don't deck the block", (I was there when he said it). They decked the block, wiping out the broach marks and stamps for the original block for his Corvette. Since nothing was in writing the shop would do nothing about it.
Specify remedy if they do deck the block, like full replacement cost of locating, buying and shipping of a correct block plus no charge for their mistake.
VerleComment
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The first question I'd ask is, " why do you need
a rebuild"? Do you have symptoms or just feel the need to do someting? If the thing isn't smoking or knocking, leave it alone!Comment
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Re: 327/365HP engine restoration-vs-rebuild
Pete, if you must have it rebuilt, try this. work into the contract ( get this in writing )with the re-builder that if the engine pad is destroyed during the rebuild. (that means any 1 character), then the penalty to be paid to you is $10,000. As usual, you get what you INSPECT not what you EXPECT!!!!
Harry
38513Comment
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Re: 327/365HP engine restoration-vs-rebuild
Thank you Duke and all who responded. The concensus from those who have heard the engine start is that I blew a connecting rod. The block is ok. and after 40 years, I need to finally do something. I'll keep looking and asking questions.Comment
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Re: 327/365HP engine restoration-vs-rebuild
Ahhhhh.... if you "blew a connecting rod" the engine would probably not start.
Why don't you give us an accurate, detailed, and hopefully unambiguous description or what is going on.
DukeComment
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