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New Engine build [message #315172] Tue, 28 March 2017 19:22 Go to previous message
dr.diesel is currently offline  dr.diesel   United States
Messages: 85
Registered: April 2015
Location: The Haute, Indiana
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I've read just about every engine build thread available here, but nothing matches what I've got in mind!

Goal:

- 2-3 week vacation duration (so a bit more gear weight)
- Towing enclosed trailer with 5000lb vehicle
- Ability to *better* maintain grades
- Willing to sacrifice fuel economy for performance, value is not a primary build consideration
- Mostly likely 3.70 final drive ratio

Considering the following:

- 4.5" Stroker 455
- C Heads (I realize at the factory 3.07 final drive Cs make no sense, but at 3.70s and 3000RPM cruise (~490ci engine) these may hold a benefit perhaps??)
- 8.5:1 True compression ratio (fully polished combustion chambers, 180F thermo)
- Roller cam

I wasn't able to find conclusive documentation on the J vs C heads in terms of intake CCs, J heads approx 190CCs and ~240 for the Cs as my guess? The Js make perfect sense at a 2400RPM cruise but the Cs might begin to shine nudging +3000RPMs. Hardened exhaust seats would of-course be installed if I went Cs.

I've already got the AL intake and Doug Headers on my current, but tired 455. This build has yet to begin, so nothing is concrete and all options are open. My local machine shop has an engine Dyno, so whatever combo I end up will WILL be dynoed.

All thoughts welcome and appreciated, thanks.




77 Kingsley
 
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