Just a few thoughts for you while you’re in the parts collecting process. I’ve built a lot of cars and engines over the years, usually high performance stuff and for the most part it’s worked pretty well.
The last couple of builds I have done I went a little bit different route……. lower RPM torque motors (440 in a 76 Dodge Stepside and my current 500 Caddy in an 83 El Camino).
I wanted to keep the engines at between 2300-2600 RPM at 75 MPH and take advantage of the torque those engines made in that area. Figuring the gear ratio was simple, figure out the rear tire size I was going to run (what would look “right” on the car) then plug the tire size and RPM into one of the on line calculators.
The hardest part of both builds was getting my head around cam/head/intake selection to make torque in the lower RPM range. Fortunately for both builds I was able to find real dyno results that for baseline (stock) engines with the same compression ratio and heads I started out with. I was also able to see the dyno results for the different mods as the engines were built with different parts to different levels. In the case of both engines (based on the Dyno) results for an out of the box hotter cam and after market intake resulted in a HP increase but did so by moving the torque peak to a higher RPM range with a net LOSS in peak torque. Further Mods did gain the torque back + and the HP figures were impressive but by that time the RPM range the engine was operating in was well above what I wanted for a highway cruiser.
In the case of both engines in reality what I ended up building was a pretty stock motor (with OE intakes in both cases). Now I could always upgrade these engines with “better” cam, intake and heads moving the RPM range up, but that kind of defeats the purpose of building a low RPM street monster.
What I’m getting at is you may want to search out some good dyno tests for the 455 and see what happens with the different mods paying particular attention to what and where the torque is going to be.
By the way I’m really looking forward to the results of your project.
The last couple of builds I have done I went a little bit different route……. lower RPM torque motors (440 in a 76 Dodge Stepside and my current 500 Caddy in an 83 El Camino).
I wanted to keep the engines at between 2300-2600 RPM at 75 MPH and take advantage of the torque those engines made in that area. Figuring the gear ratio was simple, figure out the rear tire size I was going to run (what would look “right” on the car) then plug the tire size and RPM into one of the on line calculators.
The hardest part of both builds was getting my head around cam/head/intake selection to make torque in the lower RPM range. Fortunately for both builds I was able to find real dyno results that for baseline (stock) engines with the same compression ratio and heads I started out with. I was also able to see the dyno results for the different mods as the engines were built with different parts to different levels. In the case of both engines (based on the Dyno) results for an out of the box hotter cam and after market intake resulted in a HP increase but did so by moving the torque peak to a higher RPM range with a net LOSS in peak torque. Further Mods did gain the torque back + and the HP figures were impressive but by that time the RPM range the engine was operating in was well above what I wanted for a highway cruiser.
In the case of both engines in reality what I ended up building was a pretty stock motor (with OE intakes in both cases). Now I could always upgrade these engines with “better” cam, intake and heads moving the RPM range up, but that kind of defeats the purpose of building a low RPM street monster.
What I’m getting at is you may want to search out some good dyno tests for the 455 and see what happens with the different mods paying particular attention to what and where the torque is going to be.
By the way I’m really looking forward to the results of your project.
that could tell you what clearance is like with his intake and go from there.
