Help with new engine decision
My beloved 1992 Holiday Rambler Imperial with a Chevy 454 and 4l80E trans decided to blow its rod bearing on our trip home going up a hill (it's always seemed a bit underpowered on hills since I had i...
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502HT, with Edelbrock MPFI. $$$ They will sell you a chip that comes with the intake that will plug into your ECM. Drop a set of headers and Magnaflows and there won't be a DP anywhere on the planet that will keep up with it. My desktop dyno software put it at 440 HP. Road test doing calculations based on weight and acceleration came in around 420 HP. The 502 DOES NOT need to run on premium, especially with MPFI.
I pulled my engine through the top. Removed some of the furniture before I started the project. Put down tarps, and then some old plywood over the tarps. Its a bit of a project, but doable. My advice is that once you do this, you are married to the coach and divorce is not an option. Photos here, most on page 2:
http://s213.photobucket.com/user/Daveinet/library/Engine?sort=3&page=1
On EDIT: More thoughts. Any performance modifications you do to the 454, such as a different cam, will require a retune to the ECM. If you can handle doing a bunch of reading, and can get around computers pretty well, you can learn how to retune it. You don't really need to know how to program a computer, but just knowing your way around computers is all that is required. I can point you in the right direction to get you started. Edelbrock sells their MPFI intake for the 454 or the 502, with a custom tune as part of the package. I lean towards it being worthwhile to learn how to burn chips yourself. There are a bunch of little tweaks you can do to find more power. The big thing I found was the timing curve should not be linear. There is a pretty abrupt transition at 3K rpm, which means you can have a ton of advance below that. Really changes the throttle response.
I pulled my engine through the top. Removed some of the furniture before I started the project. Put down tarps, and then some old plywood over the tarps. Its a bit of a project, but doable. My advice is that once you do this, you are married to the coach and divorce is not an option. Photos here, most on page 2:
http://s213.photobucket.com/user/Daveinet/library/Engine?sort=3&page=1
On EDIT: More thoughts. Any performance modifications you do to the 454, such as a different cam, will require a retune to the ECM. If you can handle doing a bunch of reading, and can get around computers pretty well, you can learn how to retune it. You don't really need to know how to program a computer, but just knowing your way around computers is all that is required. I can point you in the right direction to get you started. Edelbrock sells their MPFI intake for the 454 or the 502, with a custom tune as part of the package. I lean towards it being worthwhile to learn how to burn chips yourself. There are a bunch of little tweaks you can do to find more power. The big thing I found was the timing curve should not be linear. There is a pretty abrupt transition at 3K rpm, which means you can have a ton of advance below that. Really changes the throttle response.
