A12 Dilemma....

[Dejavu1]

Dilemma: I have a 33,000 mile numbers matching A12 RR with recent cam lobe issues. I'm considering using this opportunity to pull/rebuild the motor, and want it run a little stronger and make a respectable showing on the street (on the rare occasion that it's needed); but not to the extent that would hurt the value or risk damaging the matching block/etc. I've considered building another engine, but really want the car to remain "the real deal". Could anyone suggest a formula/blueprint or builder that could help me achieve these goals?
accomplish these goals?

 

[1 Wild R/T]

Awesome A12!! Love the color... I wouldn't think twice... The numbers block would be on a stand & a 512 would be living under that big ol' scoop... It'll still be the real deal... On Steroids..

 

[Jerry Hall]

Your car looks to be a serious collectors item. I understand the need to play. I agree with @1 Wild R/T keep the engine with the car and build a play engine. Everything else can be fixed except that matching numbers block.

 

[GetX'd]

She’s a stunner. Love that color - remember it well on the a12’s. That is a true classic, iconic collector package all the way around. Don’t screw w/a 33k original heartbeat. As the others have said - if you just have to play don’t mess w/that engine to do so. Not sure why that 440 6 isn’t play worthy as it sits. Mine 68 X sure as hell was and the six pack was an add on. Not a true A12 but didn’t need to be. No one ever crawled up my tail pipes. More or less they were all in the rear view mirror…..

 

[R413]

Sounds like you need a different car to play with and leave that one alone. 32K miles is rare these days. Remember it's 55 years old, don't play with it, leave it be.

Plenty of these A12's have been violated, get one of those to play with.

This is not a dilemma

 

[Dejavu1]

I really appreciate all the replies. I'm likely gonna stand down on the mods. Thank you.

 

[BSB67]

It is really a personal choice. I believe you could amp it up considerably without risk of hurting anything important.

Without really knowing your actual starting point hp/performance wise, it is hard to say what the gain would be. My money says that really good reworked heads, Mr Six Pack cam, and good exhaust (TTI - 2 1/2”), you would put 50 hp more hp in that motor, maybe more.

 

[Curiousyellow71]

If I were doing a hydraulic, or just replacing the cam I would also consider a Mr. six pack Bob K cam.

I also would have no problem freshening it up. Clean and freshen the heads up. Install arp rod bolts and have everything resized and straightened up. Once a lobe goes it's best to take it apart and refreshen it.
If it were mine w such low miles I would probably rering it and keep the std pistons in (If they checked out). But Imho..best way to insure the block survives is to bore it and run a modern light weight forged piston. They are considerable lighter and more durable. It then will have to be rebalanced. The replacement forged piston for a 69 has been discontinued for decades so I would upgrade to a 1/16 ring and a light piston.... if it needs it.

I understand why original engines are tucked away..but for most builds I prefer to keep the original in the car..a engine may get lost over time. Sadly, seen it happen.
Great car!

 

[dspur]

I really appreciate all the replies. I'm likely gonna stand down on the mods. Thank you.

Good decision. Keep it running in tip top condition and drive it occasionally, a little aggressive perhaps but not abusive, good for the car. You have a beautiful vehicle that deserves to be enjoyed and maintained. I would not take the risk personally of putting another engine in it just to play, there is value in keeping ALL of the car intact. Get a play car instead, probably be cheaper in the long run. Would love to have the A12 back I had in the 70's and 80's, but, sigh, we have all let one get away...

 

[Rebelrouser]

Dilemma: I have a 33,000 mile numbers matching A12 RR with recent cam lobe issues. I'm considering using this opportunity to pull/rebuild the motor, and want it run a little stronger and make a respectable showing on the street (on the rare occasion that it's needed); but not to the extent that would hurt the value or risk damaging the matching block/etc. I've considered building another engine, but really want the car to remain "the real deal". Could anyone suggest a formula/blueprint or builder that could help me achieve these goals?
accomplish these goals? View attachment 1680966

Great looking car, and as with any collector car how you enjoy it is your business. I am not in the group that collects a car for numbers, but for the joy, and fun of having it. After all I can remember in the 70's after the gas crunch these cars were worthless. That is when I bought my Mopar muscle cars and fell in love with them. If you want to keep it as a collector car to sit in garage and trailer to shows leave it alone. If you want to drive and lay some rubber pull the engine set it is the corner and build one to have fun with. I have built a couple 6 pack engines for customers. A little hand porting on the heads and a short duration high lift hydraulic roller makes close to 500HP and makes a very drivable package. And if you want to do it to the original block nobody will ever know but you as no numbers are messed with. If you really want to burn tires throw a stroker with light weight parts in it, that will however change the balancer and a sharp eye will catch that modification.

 

[MWbirdLOVER70]

My thoughts are to fix the cam issue and when inside go over it and see what she needs. Keep her virgin cause most collectors would prefer. As for power maybe a beefy classic toy but here I have my 70 and for cruise nights it’s my 17 challenger r/t plus big perk air and creature comforts and still a Mopar

 

[Dejavu1]

It is really a personal choice. I believe you could amp it up considerably without risk of hurting anything important.

Without really knowing your actual starting point hp/performance wise, it is hard to say what the gain would be. My money says that really good reworked heads, Mr Six Pack cam, and good exhaust (TTI - 2 1/2”), you would put 50 hp more hp in that motor, maybe more.

Thanks. I've been running Bob's cam since 1999, and have been pleased with the torque and general performance, and will likely order another. I'm leaning toward tweaking the stock engine, while not making any dramatic changes. Cam, headwork, converter, and possible headers are still on the table. Any suggestions along those lines would really be appreciated. Thank you (as well as the other B-Body guys who have commented) for the sound advice. I've been "out of the game" (so to speak) for more than a few years now, but am looking forward to tweaking the car, showing it, and seeing what the future holds. Thank you guys sincerely for being gentlemen, and refraining from the opportunity to slam me for asking the question. I'll keep you guys informed of the progress.

 

[Moparfitter]

Build it how you want, It can be put to stock again later. I’m in the process of updating what looks like the exact car(early build post a12)
Stroker, front disc brakes, strange driveshaft and forged pinions. Put old parts in storage!

Talk to Dwayne Porter at Porter racing heads.

 

[BSB67]

…The replacement forged piston for a 69 has been discontinued for decades…..

Yep. I do have a set 0.030” over. Speed Pro 2286-P Tried to sell a couple years ago, nobody interested. If your buying a piston, it’s not a great choice.

These pistons in my 67’ 440 charger (4200 lbs) factory ported heads, 6-Pack, exhaust manifolds, compression bent exhaust pipes, 3.23 gear, stock 12” converter, 0.455” lift MP cam and BFG P235s ran a best of 12.85 @ 108.75.

If I can do that, you could probably get to 12.50s easily without headers or converter.

But I suspect you know this if you know Bob K.

 

[lewtot184]

I'd build another engine and not take a chance on damaging the original. You don't need anything lumpy or radical or expensive. Head work, a little better cam (Mr. 6pak cams are engles and I like engles but I'd use a k56/k58 profile), some exhaust work (don't need headers), and ditch the 4.10"s (the engine won't need any gear or converter) and you'll have a 12 second car. The only wild card will be rather you want pump gas or mix gas.

 

[500v]

I did a numbers matching RR auto when I got the car motor had been hurt was in the trunk in pieces, one sleeve and .030 bore. Used the Bob K. Mr. 6 pak cam a lot of his advice rebuilt and rejetted carbs and changed ignition over Mopar electronic worked great and pulled hard!

 

[Dejavu1]

Good decision. Keep it running in tip top condition and drive it occasionally, a little aggressive perhaps but not abusive, good for the car. You have a beautiful vehicle that deserves to be enjoyed and maintained. I would not take the risk personally of putting another engine in it just to play, there is value in keeping ALL of the car intact. Get a play car instead, probably be cheaper in the long run. Would love to have the A12 back I had in the 70's and 80's, but, sigh, we have all let one get away...

You summed it up pretty good. That is the approach I'm planning to take. Thank you.

 

[Dejavu1]

Great looking car, and as with any collector car how you enjoy it is your business. I am not in the group that collects a car for numbers, but for the joy, and fun of having it. After all I can remember in the 70's after the gas crunch these cars were worthless. That is when I bought my Mopar muscle cars and fell in love with them. If you want to keep it as a collector car to sit in garage and trailer to shows leave it alone. If you want to drive and lay some rubber pull the engine set it is the corner and build one to have fun with. I have built a couple 6 pack engines for customers. A little hand porting on the heads and a short duration high lift hydraulic roller makes close to 500HP and makes a very drivable package. And if you want to do it to the original block nobody will ever know but you as no numbers are messed with. If you really want to burn tires throw a stroker with light weight parts in it, that will however change the balancer and a sharp eye will catch that modification.

500hp and similar torque would suit this old man just fine. I just want to make a respectable showing and "represent" old skool when I'm pulling out of a car show, or challenged by one of these newer "muscle cars". This is the second A12 I have owned. The first was a Vitamin C, vinyl top, automatic on the column, bench seat RR, that I purchased off a used car lot in Shelby NC in 1973. I drove it through high school, dated and "cruised" in it, and sold it in the mid-80s after getting married (temporary change in priorities). I was later sick over it, and found the 28,000 mile green car in Greeley, Colorado in 1999. I spent the next year restoring it, and the rest is history. Thanks again....

 

[MWbirdLOVER70]

500hp and similar torque would suit this old man just fine. I just want to make a respectable showing and "represent" old skool when I'm pulling out of a car show, or challenged by one of these newer "muscle cars". This is the second A12 I have owned. The first was a Vitamin C, vinyl top, automatic on the column, bench seat RR, that I purchased off a used car lot in Shelby NC in 1973. I drove it through high school, dated and "cruised" in it, and sold it in the mid-80s after getting married (temporary change in priorities). I was later sick over it, and found the 28,000 mile green car in Greeley, Colorado in 1999. I spent the next year restoring it, and the rest is history. Thanks again....

I’m Green with envy brother

 

[Runcharger]

I know the temptation is there to add the stroker crank, headers and aluminum heads. I see lots of dogs with these mods and I'd be embarassed at the way a lot of them perform.
I prefer the Stock eliminator approach more. Head work, stock manifolds, better cam, light pistons and maybe even lighter rods. You see a stock looking A-12 and it runs mid 12's or better through the stock exhaust and that impresses you more than the obviously modded car that doesn't run any better truth be told.
I found that on the street a Hemi really works with a stroker crank working so well with the big heads. A 440 is a totally different animal and has to be finessed differently. Using stock heads you need to apply tricks to them and there's no use adding cubes.