Qestion about numbers
Thread Starter
Instructor
Joined: Jan 2005
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Qestion about numbers
Ok guys, this is a question about my 76, not my 84. I can turn a wrench, but when they start spitting out numbers, I'm lost. I would like to know what these numbers mean, and your best quess as to Hp and what the CID would be now.
It's a 76 with a 350. The builder said it's been bored out 40 over, and then something I did not catch 18 thousands.
I understand the cylinders were bored out, which I assume is the 40 over. I also assume that Millemeters? I don't know the 18 number or what it relates to. Thats why I had a builder redo my engine, and not me :-)
Any info would be great. Additionally, he said I likely need a new carborator, but will get back to me. He claims the one on there does not look like it will dump enough fuel at the higher RPM's, which I believe. He also reccommended a "flexfan". I understand what it does, but how does that relate to horsepower?
It's a 76 with a 350. The builder said it's been bored out 40 over, and then something I did not catch 18 thousands.
I understand the cylinders were bored out, which I assume is the 40 over. I also assume that Millemeters? I don't know the 18 number or what it relates to. Thats why I had a builder redo my engine, and not me :-)
Any info would be great. Additionally, he said I likely need a new carborator, but will get back to me. He claims the one on there does not look like it will dump enough fuel at the higher RPM's, which I believe. He also reccommended a "flexfan". I understand what it does, but how does that relate to horsepower?
Last edited by mstock; Mar 11, 2005 at 11:54 AM.
Team Owner
Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The "040" refers to an cylinder overbore of .040". A reference to 18 thousandths ( .018") may be the amount the crankshaft and/or rod journals have been cut to get them round again.
A flexfan may cut the HP used by the fan because the blades straighten out due to centrifugal force at high RPM so the blades do not move as much air, reducing the power it takes to turn it. A fan mounted on the water pump may take upward of 5HP to operate and that's one reason why electric fans are so popular. Even the standard declutching fan is a decent deal if the clutch works OK.
Unless you have made some serious mods to your motor other than the bore, the stock Quadrajet carb should flow plenty of air. Changes can be made to the metering rods and jets to handle more fuel, but again it depends on the engine mods involved. Did you add a bigger cam, aftermarket heads, headers, and a perormance intake manifold??
A stock L48 (180HP) motor or even the L82 (210HP) in the 76 was one of the weakest 350's ever to go into a Vette. They work for everyday street use but they certainly did not have a lot of power or torque. Even the L82 had only 255 ft-lbs of torque in stock trim.
A flexfan may cut the HP used by the fan because the blades straighten out due to centrifugal force at high RPM so the blades do not move as much air, reducing the power it takes to turn it. A fan mounted on the water pump may take upward of 5HP to operate and that's one reason why electric fans are so popular. Even the standard declutching fan is a decent deal if the clutch works OK.
Unless you have made some serious mods to your motor other than the bore, the stock Quadrajet carb should flow plenty of air. Changes can be made to the metering rods and jets to handle more fuel, but again it depends on the engine mods involved. Did you add a bigger cam, aftermarket heads, headers, and a perormance intake manifold??
A stock L48 (180HP) motor or even the L82 (210HP) in the 76 was one of the weakest 350's ever to go into a Vette. They work for everyday street use but they certainly did not have a lot of power or torque. Even the L82 had only 255 ft-lbs of torque in stock trim.
Thread Starter
Instructor
Joined: Jan 2005
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Mods made
I have not seen all the specs on what he did. I bought it used, and never got into the engine...till now. It does have a set of headers on it, and a holly 4bl Carb. Beyond that, I don't know what if any mods were done before. Other than what I stated before, no additional mods have been made by myself. They are talking about taking it over to Curt Carborator, if that means anything to you Detroit guys. If all works out, i can't complain about the cost. I got a great deal on the rebuild, and all the other parts are being done at cost, with no labor, as it is being done as a student project. They suggested replacing the clutch, which I agreed to, and the flexfan mod. I don't race it, so that is not an issue. I would just like to have some pep...something if failed to have before the rebuild. Also, I don't have a ton of moeny to put into it. I also have my 84 project, which has taken up a bit of money as well :-) 
Safety Car
Joined: May 1999
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From: Atlantis
Cruise-In I Veteran
Possibly the 'eighteen' number you thought he quoted was "ten ten" which could have easily been interpreted as "eighteen".
"Ten Ten" would be a crankshaft turned ten thousandths undersized on the main and rod journals.
That is a fairly standard occurence to clean up a used crankshaft.
"Ten Ten" would be a crankshaft turned ten thousandths undersized on the main and rod journals.
That is a fairly standard occurence to clean up a used crankshaft.
