Joe383
Full Access Member
- Joined
- Jun 18, 2015
- Posts
- 133
- Reaction score
- 7
- Location
- Moses Lake
- First Name
- Joseph
- Truck Year
- 85
- Truck Model
- C20
- Engine Size
- 454
It will cost you a little more than $2500 to put the L31 motor in your truck if you go all new. If you reuse the old parts like your water pump, carb and distributor you might be around $2500. You have to replace the cam gear on the distributor with an aftermarket melonized gear. I did a full cam swap and replaced every thing but the short block on my motor but leaving it stock would have been just as good cuz it has a lot of power. Your largest expense after the motor will be the intake manifold. A ram jet 350 cam would be a good swap for this motor but I don't know if the stock valve springs will handle it. I am very happy with my vortec motor. It is way better than rebuilding a stock motor. I like the roller cam, I did a cam swap with the lifters still in the block. The rods look awesome, it has a windage tray, the 2 timing cover bolt holes that are usually missing are drilled and tapped unlike a stock vortec, its a 4 bolt main and the valve cover and oil pan gaskets are reusable.
The bads about it for me were #1 I had to machine the heads to except comp cams beehive springs to get them to fit and LS6 springs did not fit with out machining either#2 there is no hole for a mechanical fuel pump so you have to run an electric fuel pump #3 the timing chain is loose and I would run an older style timing chain cover and aftermarket double roller timing chain as I did. I could not reuse my throttle bracket cuz the old one was using the bolts that held the intake to the head and had to get one that bolted to the carburetor instead. You have to replace the distributor gear if using the stock cam.
I had talked to comp cams about different cams and almost had a cam a custom cam made to use the stock parts. If you go this route you can use a stock distributor gear and springs making the build a little easer. The cam was $280 shipped to my door from comp cams. I had to replace my springs due to my cam choice but having a cam custom made to use the stock parts is an option.
The grind I almost had made was 3595 intake lobe and 3597 for the exhaust the cam would have looked like this 206/218 @0.050 258/270 ADV .435/.447 lift on a 112 LSA and 108 ICL I was going to put .15 shims under the springs to raise the seat pressure a little. This cam with a performer EPS and a demon carb 625 street demon carburetor would be a great set up and is almost what I built but I wanted a little more power so I went larger on cam and carb. Might still grind this cam once the motor is in my truck though and swap carburetors to the demon. Should pull from off idle to around 5K and if I had to guess on power I would expect around 300HP at the flywheel with a little under 400 FTLBs.
I feel the vortec is the best bang for the buck if you are just looking for a mild build but I spent $580 just on machine work to get the springs to fit and having screw in studs installed for my heads and would have been better off getting a short block and some aluminum heads.
The bads about it for me were #1 I had to machine the heads to except comp cams beehive springs to get them to fit and LS6 springs did not fit with out machining either#2 there is no hole for a mechanical fuel pump so you have to run an electric fuel pump #3 the timing chain is loose and I would run an older style timing chain cover and aftermarket double roller timing chain as I did. I could not reuse my throttle bracket cuz the old one was using the bolts that held the intake to the head and had to get one that bolted to the carburetor instead. You have to replace the distributor gear if using the stock cam.
I had talked to comp cams about different cams and almost had a cam a custom cam made to use the stock parts. If you go this route you can use a stock distributor gear and springs making the build a little easer. The cam was $280 shipped to my door from comp cams. I had to replace my springs due to my cam choice but having a cam custom made to use the stock parts is an option.
The grind I almost had made was 3595 intake lobe and 3597 for the exhaust the cam would have looked like this 206/218 @0.050 258/270 ADV .435/.447 lift on a 112 LSA and 108 ICL I was going to put .15 shims under the springs to raise the seat pressure a little. This cam with a performer EPS and a demon carb 625 street demon carburetor would be a great set up and is almost what I built but I wanted a little more power so I went larger on cam and carb. Might still grind this cam once the motor is in my truck though and swap carburetors to the demon. Should pull from off idle to around 5K and if I had to guess on power I would expect around 300HP at the flywheel with a little under 400 FTLBs.
I feel the vortec is the best bang for the buck if you are just looking for a mild build but I spent $580 just on machine work to get the springs to fit and having screw in studs installed for my heads and would have been better off getting a short block and some aluminum heads.