Looks like nobody wants to buy any of my parts currently for sale (yeah, the economy SUCKS all over), so I'll be putting the Challenger's 452 back together w/ the stuff I have on hand. Anyway, I'm bored... and curious about whether people think the work being done as part of the rebuild will have any change on how it runs.

Differences between "before" and "after":

Bottom end
- Cylinder bores re-honed
- Switching to file-fit moly rings from the old Total Seal Gapless top rings

Top end
- Same Stage VI heads, but the valves & seats got touched up

Lift -- Int / Exh
.100 --- 69 / 53
.200 -- 143 / 108
.300 -- 213 / 146
.400 -- 262 / 181
.500 -- 293 / 211
.550 -- 305 / 222
.600 -- 307 / 231
.650 -- 307 / 237
.700 -- 307 / 243

- Switching from 1.5 int & exh rockers to 1.6 intake / 1.5 exhaust combination
- Will either shim the old valve springs or replace them entirely (haven't decided, yet)
- Matched intake runners to head entries (match was basically OOB before)

Cam
- Old - COMP XX .874" flat-tappet solid used w/ 1.5 rockers int & exh
298 @ .20"
266 @ .050"
180 @ .200"
.400" lobe / .600" (1.5)
108 LSA + 2.5 (ICL measured at.020" lobe lift)
Ran w/ .024" lash hot

- New - Hughes 6468 flat-tappet solid
Duration at .050": 264 / 268
Lift: .633" (1.6) / .611" (1.5)
LSA: 108 + 3
Lash: .020" Hot


I guess the main questions are (a) whether the change in ring configuration & hone job will make any difference and (b) if the new cam & rocker ratio combination is worth anything vs. the original.

And I'm really hoping I can actually answer these questions sometime in the next 6-8 weeks.

huh uh.

Look forward to the results.

Those cams are very close. Did you check the 0.200" duration on the Hughes cam? Judging by the lobe lift (.395/.407), it should be within a couple degrees. My first guess is that the new cam is a tiny bit milder overall, but will idle worse. There is a chance it might handle the car's full exhaust system better than the straight pattern 108 Comp Cam.

If the car changes by more than 0.05 seconds (plus or minus) I will be surprised.

I'll do a complete intake & exhaust lobe profiling during the assembly, but can't say how much different the cams are (other than on paper) at this point. I don't think they're much different, either, and the only "real" change will be from stepping up the intake rocker ratio.

I'd actually like it to run comparable to before so I don't have to question what I did wrong during the rebuild.