Vortec Head Modifications : Small Block Engine Cylinder Heads | Chevrolet Performance : The real weakness of the vortec head is the exhaust port, a fact that is readily apparent when you get into porting these heads.. The heads are easy to spot because of their intake manifold retention bolt configuration. The stock valve job can be improved on vortec heads. Then, fuel rails and all that. So the best bang for the buck is gm vortec head but does require a special intake and lots of egr work if you need egr to remain emission legal. Lightweight hollow stem ls3 valves can be cut to 2.000 in.
So the best bang for the buck is gm vortec head but does require a special intake and lots of egr work if you need egr to remain emission legal. I ported mine and fully worked the exhaust port (bowl work and contouring the runner). I will need to cut (reduce the height) of the valve guide boss.this is the curse (or part of the curse) of the vortec heads. The real weakness of the vortec head is the exhaust port, a fact that is readily apparent when you get into porting these heads. An example = look at my photo album.
This vortec design special performance cast iron cylinder head features revised intake and exhaust ports and is machined for 2.00 intake valve and 1.55 exhaust valves. Lightweight hollow stem ls3 valves can be cut to 2.000 in. Seach this forum for a ton of info. Joined jun 15, 2005 · 2 posts. The real weakness of the vortec head is the exhaust port, a fact that is readily apparent when you get into porting these heads. One way to tell is by the casting numbers on the heads and block, you can google them to find out. We used up about 10 heads, numerous valves, and about $50,000 worth of labor. This is the speed secrets episode for you!
Discussion starter · #1 · jun 15, 2005.
I am not going to install lash caps. I will need to cut (reduce the height) of the valve guide boss.this is the curse (or part of the curse) of the vortec heads. My cams gross lift is.559. I ported mine and fully worked the exhaust port (bowl work and contouring the runner). We used up about 10 heads, numerous valves, and about $50,000 worth of labor. Can be machined for 2.020/1.600 valves. 290 hp (216 kw) at 4000 rpm and 410 lbâ·ft (556 nâ·m) at 3200 rpm. The cam is based on the maximum lift for stock vortec heads and is a single pattern 215d/470l on a 112 center. 308 ft/lb torque @ 3,900 rpm. Im trying to make them suitable for my selected camshaft. Rocker arm studs can be pinned or drilled and tapped to 3/8. The worst piece on the whole tpi system is the cold start injector or referred to as the 9th injector. One way to tell is by the casting numbers on the heads and block, you can google them to find out.
One way to tell is by the casting numbers on the heads and block, you can google them to find out. I will need to cut (reduce the height) of the valve guide boss.this is the curse (or part of the curse) of the vortec heads. The heads are easy to spot because of their intake manifold retention bolt configuration. The real weakness of the vortec head is the exhaust port, a fact that is readily apparent when you get into porting these heads. My cams gross lift is.559.
The worst piece on the whole tpi system is the cold start injector or referred to as the 9th injector. Discussion starter · #1 · jun 15, 2005. Upgrading lm7 cylinder heads the stock heads can be cnc ported for more airflow and milled up to.030 in. The vortec 350 came in hundreds of thousands of chevrolet and gmc pickups, suvs, and vans from 1996 to about 1998, so they are easy to find and relatively inexpensive to build. Flow numbers can be as high as 325 cfm at.600 lift. The true vortec 4.3 came out in the mid to late nineties. Seach this forum for a ton of info. If you want the motor to live a long life plan on adding a forged crank and rods, and i'd.
I ported mine and fully worked the exhaust port (bowl work and contouring the runner).
What is the most obvious way to set the true vortec apart from the older versions, if you have the heads off, the valve shroud on the older 4.3 is bean shaped. I ported mine and fully worked the exhaust port (bowl work and contouring the runner). Joined jun 15, 2005 · 2 posts. I will need to cut (reduce the height) of the valve guide boss.this is the curse (or part of the curse) of the vortec heads. You also have the option of many aluminum heads. Camshafts with more than 0.475 lift require machining valve guide bosses and checking valve seal to valve spring retainer clearance. Rocker arm studs can be pinned or drilled and tapped to 3/8. Then, fuel rails and all that. Are you looking to get almost 100 more horsepower from your gm 350 crate engine? Upgrading lm7 cylinder heads the stock heads can be cnc ported for more airflow and milled up to.030 in. Its a 4.3, but the exact same setup as a 5.7. My cams gross lift is.559. The true vortec 4.3 came out in the mid to late nineties.
I ported mine and fully worked the exhaust port (bowl work and contouring the runner). 298 hp @ 5,500 rpm. Comp cams recommends that its pn. The stock valve job can be improved on vortec heads. Are you looking to get almost 100 more horsepower from your gm 350 crate engine?
Starting in 1996, on several gm trucks and vans, the l31 vortec heads came on the scene. Seach this forum for a ton of info. Then, fuel rails and all that. One way to tell is by the casting numbers on the heads and block, you can google them to find out. Valve spring seat diameter is 1.280. Featuring the comp cams xm270h ca. Just be careful with used vortec heads as they are prone to cracks after 100k+ miles of heat and cooling cycles, iron cracks. By changing the springs, the distance between the retainers and the valve seals hasn't changed.
My vortec heads are good to.500 in/.530 ex (with 'forgiveness' in mind) with common components used and absolutely no machining done to the heads valve guides/spring pockets.
The true vortec 4.3 came out in the mid to late nineties. As illustrated in the pics in post #60; Valve spring seat diameter is 1.280. This is the speed secrets episode for you! Flow numbers can be as high as 325 cfm at.600 lift. Camshafts with more than 0.475 lift require machining valve guide bosses and checking valve seal to valve spring retainer clearance. Seach this forum for a ton of info. Rocker arm studs can be pinned or drilled and tapped to 3/8. Are you looking to get almost 100 more horsepower from your gm 350 crate engine? These heads are good for a minimum 50hp gain. 308 ft/lb torque @ 3,900 rpm. There are other, smaller points that are important to know because they affect cam selection. Two years ago we undertook an exhaustive (no pun intended) study of the vortec head in numerous modified states with different valve sizes, throat cuts, valve jobs, port mods, guide mods, etc.