We have the AIM used by Tonawanda to assemble Cosworth Vega engines, both years, but I have never seen an engine AIM for our Corvettes. I assume they exist. Has anyone ever seen one? Are they available?
Duke
Duke
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Re: Corvette engine Assembly Instruction Manuals
Hi Duke:
Happy Easter almost.
Could it be that GM had the forethought to realize Vega owners would have the need to tear their engines apart more often than Corvette owners and provided for this certainty ? :)
jer
P.S. Whadda ya doin up so early ? -
Gee, Duke of Earl.....
No need for AIM to assemble overhead valve engine. All the specs are provided in the service manuls for respective years, along with torque sequences. A dude of your caliber should be able to assemble a V-8 blindfolded.Comment
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Re: Gee, Duke of Earl.....
I don't think I'd want to attempt assembling small block blindfolded, George, and the service manual has most of the information I need using my corrective lenses, though it's not guaranteed to be accurate. Case in point. The Cosworth Vega service manual specs the 5/16-18 oil pan bolts at 25 lb-ft installation torque. For years everyone wondered why they were pulling the threads out of the case and overcrushing the gaskets. When we got the engine AIM we found out why. The proper spec is 10-15 ft-lbs. You see, the AIMs are "engineering documents" and are constantly maintained an revised to correct errors and update part and assembly information. Once the service manuals are printed - that's it. It's up to the user to find and correct all the errors - usually the hard way.
AIM sheets as you know also have a "change record" which allows us to chart changes in engine assembly configuration, which is interesting to most historical techo-freaks like us. Right now my interest is in researching the "double gasketing" of high compression small blocks in the early to mid-sixties. The AIMs should tell us when it started, if/when it stopped, and whether there were any changes in head gasket part number.
As with the vehicle AIMs, the engine AIMs would allow us to account for physical changes in engine configuration, particularly running changes, and offer information on possible "upgrades".
DukeComment
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Seems to me that the Cosworth folks.....
lack common sense. All different grade bolts have a published max. torque apec. Now if youre twisting a 1/4" bolt down to 35 lbs. shame on you, regardless what the shop manual says, you should know better, and I am not talking about the guy doing his first rebuild, I am talking about guys turning wrenches that KNOW bolt sizes & bolt grades. If I came upon a bolt spec that specified torque setings that exceeded the bolt, it would be an immediate red flag.
Duke, you mean to tell me that with your vast knowledge and experience, you would not be able to build a Chevy motor without the use of a guide? In your response, you wrote a lot of words but you didn't say anything. From day one, all che small blocks & BB are assembled the same way; main & rod bearing clearances unique to small & BB, piston orientation, ring gaps, cam positioning, put the crank in the main saddle, torque the studs to specs, install cam, timing chain, torque the cam gear to specs, rotate crank, and check for bind, install pistons, torque rod bolts to mfg. specs, install heads and torque in sequenct to specs, install intake, torque in sequence, etc, etc, etc.....same routine for more than 40 years, longer if you count the six banger. I doubt the AIM would turn up some revelation that no one has ever heard about, except to the Cosworth crowd.Comment
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What about the SB double head gaskets?
I've never seen a reference to double gasketing the heads on a high CR small block in a service manual. Only the engine AIM can give us hard documentation on the dates of this practice. The standard bolt torques cover a wide range and are usually published for fastening with an equivalent grade nut. That's why the AIMs usually have a specific torque or torque range narrower than the "standard range" for each application. Otherwise there would be no need to specify torque values - just give everybody a "standard table". Twenty-five foot-pounds on the 5/16-18 threading into an inch of cast iron is on the high side, but within bounds, but not for aluminum. Ever overhauled an aluminum engine, or set the lash on sixteen valves after a reseat on a design that uses shims that require special tool to change? It's a different ballgame than a Chevy V-8. More like working on a Jag or and Alfa. A helicoil kit is part of your standard toolbox.
DukeComment
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No A.I.M. for Flint V-8's
Duke -
There was no A.I.M. for Flint V-8's; their specs and assembly processes were documented on "Op Sheets" (Operation Description Sheets) which were locally generated by their Process Engineering Department strictly for internal use and were never published outside of Flint Engine. The only place there would have been a complete, updated set would be the Master Book in the Process Engineering office. When the product engineers at the Tech Center made a change, they wrote an ECR (Engineering Change Recommendation), and once that was approved (cost, testing, validation, investment, etc.) and the change was actually approved for production, an N.P.C. (Notice of Production Change) was issued by the Chevrolet Production Planning Department which detailed the change to be made, part availability, coordination with other parts, etc. The ECR and NPC triggered the actual change at Flint, which they documented on their Op Sheets for the particular machining or assembly stations involved. An unmolested Master Op Sheet Book would be a real find, but I'm sure they went the way of the wrecking ball when they tore the plant down.
Car and Truck A.I.M.'s were Chevrolet Engineering documents, generated at the Tech Center, as nearly half the Chevrolet passenger cars and trucks were built at GM Assembly Division plants (as opposed to Fisher Body/Chevrolet plants) which were not under Chevrolet Manufacturing's control. GMAD had their own Process Engineering Department which took both the Fisher Body O.D. sheets for the body and the Chevrolet A.I.M. sheets and converted them into a GMAD document called an O.D. (Operation Description) Sheet which was a standardized format for all 16 GMAD assembly plants.
Chevrolet engines were all built internally by Chevrolet Manufacturing, so no Engineering-issued machining or assembly instruction documents were felt to be necessary; Chevrolet Engine plants "did their own thing" and documented those things by whatever method suited each plant's operations best.
JohnComment
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Thanks, John!
I was hoping you'd pipe in on this one. Happy Easter!
DukeComment
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Re: Thanks, John!
Ditto!...............Varooom.Comment
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