Is anyone running the ht383 gmpp?

[Hammond68]

I'm thinking about getting this engine. There doesn't seem to be many reviews for how long this engine has been available.

[jocko]

I've been looking at one too. There are several folks on the board that have them. I like the fact that it has a mech fuel pump (as compared to an L31R, which requires electric), but it's more than twice the price too. It's a good engine, no doubt about that.

[diesel burner]

I bought the ht383 in 1998 for my 71 c20 with turbo 350 behind it. I absolutely love that motor. I upgraded to an edelbrock performer rpm intake and hedman headers with 2.5" exhaust with flowmaster 40s. Now the same motor is in my 71 k20 with an nv4500 behind it. Probably have close to 80,000 miles on it. Only thing I don't like is the vortec intake manifold. I need to replace the gaskets as they are leaking(sucking air)

[Hammond68]

Thanks for the reply diesel. Did your mpg drop badly,stay the same or improve any?

[diesel burner]

I started with an edelbrock 1406 carb and my mileage was the same as the old 350, but I felt like I was driving with my foot to the floor all the time. I couldn't pull out to pass without it kicking down a gear. I put an edelbrock 1411 on it and my mileage went up 2 mpg and it is a lot better to drive. In my C20 with 3.73 gears I was getting 14-15 mpg. In my K20 with 3.54 gears and overdrive I'm getting 14 at best.
But the power from such a mild mannered motor is great. Idles smooth, great low end.... I love it !!!

[Hammond68]

Thanks for the info diesel. I just didn't want to get poor milage compared to a 350. I'll probably buy this engine in about a month.

[jocko]

That sounds like a great combo.