My 68 caprice, need advice...
fatboy gixxer
01-12-2009, 09:19 PM
This is my 68 Caprice. It has a 396 big block which is stock, and new flowmasters. I was lookin to get some serious power out of her, but I have no idea where to start (First Chevy). I have a budget of about 3 grand right now and I wanna put it under tha hood. Any suggestions?
Great site btw...
Sorry the pics are so big, the first one is before paint. I decided I didn't like the aluminum strip that ran along the side so I removed it. The new color is evergreen frost metallic pearl. The rims are 22in DUB shorelines.
http://i223.photobucket.com/albums/dd253/fatboygixxer/DigiPics007.jpg
http://i223.photobucket.com/albums/dd253/fatboygixxer/DigiPics016.jpg
Great site btw...
Sorry the pics are so big, the first one is before paint. I decided I didn't like the aluminum strip that ran along the side so I removed it. The new color is evergreen frost metallic pearl. The rims are 22in DUB shorelines.
http://i223.photobucket.com/albums/dd253/fatboygixxer/DigiPics007.jpg
http://i223.photobucket.com/albums/dd253/fatboygixxer/DigiPics016.jpg
MagicRat
01-12-2009, 09:56 PM
Nice car. The 396 engine is a bit rare in the full-size line but it obviously puts you ahead of the game. That engine has lots of performance potential.
First of all, those 22's are an issue. When building performance, you need a plan first, to fit the equipment and your expectations.
You have to look at the driveline, from engine to wheels as a complete unit; all the parts have to work together. Those rims make for a substantially taller wheel than stock. This means higher overall gearing. This means the first gear launches are going to be softer, but with fewer engine revs at highway speed.
So you have to decide on the correct overall gear ratio first before building an engine.
What kind of performance do you want? Really hard launches, or high top speed and effortless highway cruising?
If you want the former, you will have to get steeper differential gears and/or go with smaller rims; so the overall tire diameter is closer to stock.
If the latter is good, then you probably can stick to what you have.
With that out of the way, you can plan the power curve to fit the gearing and your use.
If you are going for steeper gears, the engine will be revving higher, more often. This means you can select components that will allow for building max power at high revs. Also, often the torque converter will need to have a higher stall to take advantage of the engines power curve.
If you are keeping those 22's and the stock gears, you will need to build low and mid-range torque. Often this means that the engine will build overall less peak horsepower than a high-rev set-up, but it will match the gearing much better and will result in better performance. Also, the stock converter will be a better match.
First of all, those 22's are an issue. When building performance, you need a plan first, to fit the equipment and your expectations.
You have to look at the driveline, from engine to wheels as a complete unit; all the parts have to work together. Those rims make for a substantially taller wheel than stock. This means higher overall gearing. This means the first gear launches are going to be softer, but with fewer engine revs at highway speed.
So you have to decide on the correct overall gear ratio first before building an engine.
What kind of performance do you want? Really hard launches, or high top speed and effortless highway cruising?
If you want the former, you will have to get steeper differential gears and/or go with smaller rims; so the overall tire diameter is closer to stock.
If the latter is good, then you probably can stick to what you have.
With that out of the way, you can plan the power curve to fit the gearing and your use.
If you are going for steeper gears, the engine will be revving higher, more often. This means you can select components that will allow for building max power at high revs. Also, often the torque converter will need to have a higher stall to take advantage of the engines power curve.
If you are keeping those 22's and the stock gears, you will need to build low and mid-range torque. Often this means that the engine will build overall less peak horsepower than a high-rev set-up, but it will match the gearing much better and will result in better performance. Also, the stock converter will be a better match.
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