1966 Newport Mods

[Bighead440]

Well, I finally bought another C-body 2dr. hardtop. A 1966 Newport that I have been following for a while became available at a price I couldn't refuse. It's the turbine bronze color with a white painted top and black interior. When I first started following the car, the owner had my machinist friend doing the original 383. The block was cracked (to the outside, between the "freeze" plugs) and the machine shop guys were trying to weld/braze it up. I offered a bare 383 block with caps (actually a '69 RR "HP" block) to correct the crack issue. The shop gave me a 400 BB bare block in trade, and proceeded to build the '69 block to '66 specs. Later the guy wanted a 4 barrel carb/intake installed, so I used a '68 383 iron factory intake and AVS carb and upgraded that for him. Even later, he wanted to do away with points, so I converted the thing to Pertronix and their 12v coil (no ballast resistor). I know the rebuilder pistons used in the overhaul have killed the compression (maybe 8.5:1 now) so I have to stay small with the cam. I'm thinking of installing the Crane 643941 cam (216/228@.050", .454/.480" lift, 112LSA) with upgraded springs (Comp 911, etc.) and using a 670 Holley Avenger vac-sec carb. I have some Hedman shorty headers or some '69 HP manifolds to use for better exhaust flow, and a 3.23 ratio chunk for the rear. Depending on how it acts, I might add a 11" converter (stock RR type) if needed. Thoughts?

 

[65sporty]

I like the mod's you are planning, I would like to know how the cam sounds.

 

[LocuMob]

Sounds like the majority of the same/similar mods I've done, upgrade to electronic ignition, Edelbrock Performer, Edelbrock 750 CFM carb, a Purple shaft .484 cam and 2500 stall convertor. I finally broke down and got tti headers to replace my horrible exhaust that came with the car.

Sounds like you have the basics for your cruiser all ready picked out. Nice to know the history if the car too.

 

[Bighead440]

I like the mod's you are planning, I would like to know how the cam sounds.

I have run this cam several times in customers' 383 B-bodies but never a C-body. It idles with authority and pulls good vacuum. I would use a bigger cam in a 440, but it seems suited to a warmed-up B engine.

 

[CBODY67]

The "rebuilder" pistons normally have a .020" "de-stroke" to better tolerate the lower octane fuels, starting in the earlier 1980s. The orig-spec compression ratio for the 2bbl was 9.2 with the closed chamber heads. Unless you use the Mopar Perf porting templates, any valve lift past about .450" might well be wasted, not to mention the issue of valve spring longevity, which can vary from brand to brand of springs. The 112 LSA is good, as are the .050" timing specs.

It's been a while since I looked at piston compression height specs, but I suspect that with the original head gaskets, rather than the composition gaskets of late, the CR could be more like 8.7 or so . . . near what you suspected. Be sure to CC the heads, to ensure they are at min spec, for good measure.

Back in about '71, there was a NY/NJ-area speed shop that did dyno tunes on a '70 383 4bbl B-body and then did the same thing to a '71 383 4bbl B-body. Interesting thing was that with the same things done to them, the chassis dyno produced almost similar results, even with the lower compression ratio in '71. "CARS" magazine, I believe. They also did an article on putting a Kendig carb on a '71 RR 383.

The 11 inch converter is really 10.75" diameter. The RR and HEMI part numbers used to be the same as for a Slant 6 225. I looked up a Chry reman torque converter and that's the way it was. The size of the torque converter also relates to the total fluid capacity of the trans.

Nice looking car. Should run good, too.

CBODY67

 

[Bighead440]

The "rebuilder" pistons normally have a .020" "de-stroke" to better tolerate the lower octane fuels, starting in the earlier 1980s. The orig-spec compression ratio for the 2bbl was 9.2 with the closed chamber heads. Unless you use the Mopar Perf porting templates, any valve lift past about .450" might well be wasted, not to mention the issue of valve spring longevity, which can vary from brand to brand of springs. The 112 LSA is good, as are the .050" timing specs.

It's been a while since I looked at piston compression height specs, but I suspect that with the original head gaskets, rather than the composition gaskets of late, the CR could be more like 8.7 or so . . . near what you suspected. Be sure to CC the heads, to ensure they are at min spec, for good measure.

Back in about '71, there was a NY/NJ-area speed shop that did dyno tunes on a '70 383 4bbl B-body and then did the same thing to a '71 383 4bbl B-body. Interesting thing was that with the same things done to them, the chassis dyno produced almost similar results, even with the lower compression ratio in '71. "CARS" magazine, I believe. They also did an article on putting a Kendig carb on a '71 RR 383.

The 11 inch converter is really 10.75" diameter. The RR and HEMI part numbers used to be the same as for a Slant 6 225. I looked up a Chry reman torque converter and that's the way it was. The size of the torque converter also relates to the total fluid capacity of the trans.

Nice looking car. Should run good, too.

CBODY67

Yes 10 3/4" and the Hemi used 7/16" bolts instead of 5/16" like the 340, 383 etc. We used a 10 3/4" D250 converter behind a Street Hemi cammed OTHERWISE stock '71 440 powered '67 Coronet with 3.91 gears and ran 12's in the 1/4!! lol