For those of you that want to upgrade the old tires 200 and 229 inch motors in your gbody . This is a simple bolt in with a intake because of the change of the newer upgraded vortec heads. This 4 barrel intake can be had off of ebay or new from summit for the vortec heads and the 4.3 motor. One other thing would be the HEI for the even fire vortec motor rather then the odd fire 200 and 229 motors. With those two things needed the motor is next. I just completed a build on a 1999 4.3 from a blazer that had a rod knock. These motor are as simple as it can get with the rebuild. Same set up as the 350 vortec motors and they use many of the same parts. The crank kit came with the new reman crank and the rods and main bearings. If the crank is in good shape then mabe just a polish will do. As for the main bearing these are the same as the 350 except you will have one set left over and they are cheaper then buying a set just for the 4.3. Rod bearing on the other hand are just for the 4.3 only and you must get them in the size you need. Cam bearing are the same as the 350 except you will have one of the two with the same number left over, so again money saved if you are doing this your self. The pistons are the same as the 96-2000 5.7 motors with the metric ring package. I build a lot of the 350 vortec motors so I have the rings on hand and now I have two new extras. Three more 4.3 and I have enough for a v8. New timing chain, pan gasket and the head gasket set and your done. These motor will increase the cubic inches for 33 for the 229 to 62 from the 200 inch motors. As the old saying goes their is no replacement for displacement. They are cheap to get your hands on and to rebuild and they have a roller cam, all pluses for a engine swap or upgrade. With some porting on the heads a cam up grade headers converter and gears this thing would turn a lot of heads. Very easy to make 300+ HP and their 200 lbs. less then a V8.
4.3 Build
- Thread starter Yav8
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The dyno numbers were from some years back when Car Craft did one using the old heads with the ramp in the intake port. They ground out as much as they could to get the best flow at the time. Now with the 96 and newer Vortec heads and a good intake the numbers should be easy to surpass. The cam they used was the biggest hyd. roller from Comp Cams. You can look up the cam numbers your self. I see where in my book they have one for the balance shaft and non balance shaft motors. I have a old book so their might be something better now. The one I built had a custom grind Ultra Dyne just for the set up I had. Pull very hard right up to 6200rpm and then the PG would shift. The vortec intake should be listed in the Summit book, but I have seen them on ebay, just look up vortec intake. If you want to put some compression in the motor the small dome pistons from KB will work with the stock vortec heads. If you want to really up the compression then do some grinding on the square hump by the spark plug and then you can use any dome piston that will fit. Stock they are only 9-1 with the stock heads, even a set of 350 flat tops would be a help.
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