MrMopowered

If you've been reading my last posts, you know the current devolpment with my car. For those of you who haven't been folowing the story, i'll lay it out. I currently own a '70 Challenger R/T. The car has 37,000 original miles and is a true unrestored survivor. This is great, except for if you actually want to drive it. Yes, I drive it like it was meant to be driven- if you've got a problem with that, then you're reading the wrong post. I always thought the car was underpowered, and you guys helped me confirm that. I'm running leakdown and compression tests this weekend. The results may indicate a serious problem- which would require a rebuild.Heres my predicament: If I rebuild the motor, most would say it ceases to be a survivor. Remember that everything is pretty much original under the hood, so understandably im hesitant to yank it all out. On the other side, you gotta do what you gotta do. Plain and simple. If theres something seriously wrong, I can't just ignore it. Besides, I plan on keeping this car until someone pries the keys from my cold, dead fingers. So at that point does it even matter? If I don't end up needing a rebuild right now, its just prolonging the inevitable. I'd really like to know what your take on it is.

MrMopowered

P.S.
Call me a dumb teenager but it's not like I thrash the car from stoplight to stoplight everywhere I go, and its not like the car hasnt seen the occaisional hammer drop before. I talked to the original owner and he used to race it out at riverside from new- i'll be getting the old timeslips in the mail

stickshifted

not to sound like an *******, im just asking for curosity's sake, but what the hell is a teenager doing driving a 440 challenger - let alone a 1970 440-6

was it your dad's or what?

now on to your motor. dude, tuning is something thats experience and patience especially with 3 carbs to work with instead of just one. most of the time when people have troubles with a carburated car, unless somehting is majorly wrong, its usually problems with the idle, timing, and air/fuel mixture not being set properly.

i believe theres a book you can get about how to tune 6 pack engines. you just gotta know what your doing. you shouldnt need to rebuild that engine after only 37,000 miles - unless by you beating on it to harshly causes you to spin a bearing or something. before you drive it crazy, do you wait or drive nicely and slowly when the car is warming up after a cold start, do you change the oil regularly? do you rev it up like a jackass right when you've first fired it up in the morning? have you over-revved it recently? pushrods can bend if you spin it too high, and you can do worse things like float valves if your not careful.

i know these are no-brainer questions, but if your doing any of thise things, you might have messed something up.

btw, you said your car's engine is "all original" right? your distributor will have points that need to ge replaced and re-gapped every now and then as part of a regular tune up prodecure.

also i dont know if 440-6 engines came with soild cams, but if they did you gotta ajust your valve lash every 1000 miles or so. or it you have a hyd cam with ajustable rockers - its just another thing to keep track of.

stickshifted

+1

i forgot to add, if you havent already, you NEED to buy the book "How to Rebuild Big Block Mopar Engines" there will be a lot of information the section, "Is it time to rebuild?" and im referring to the older book that came out in the 80's.

in my book how to rebuild a mopar small block, theres a whole section on how to diagnose pretty much every problem a carburated v8 engine can possibly have, and what kind of tests you can do - ex - leakdown test, compression test, power balance test. and what the symtoms look like and sound like, and it will tell you how to fix these problems without needing to rebuild the motor.

your motor should be good for at least 100k miles as long as you're moderatly nice to it and keep it well-maintained. these motors are very mechanically simple compared to todays engines, and all it takes it patience, creative thinking, the right tools, and the willingness to figure out what your problems are.

MrMopowered

Thanks as usual for the input. I was just wanting to gather opinions from some other mopar guys. Funny you should mention that book commando; I already have it. I took the plugs out today. A couple were perfect or damn near. A few more were so-so. And two or three had oil on them. I took them to the local engine guru to get a second opinion. He said the oily ones and minor smoke on startup startup both meant the same thing- it needs headwork (valves). He said from looking at the ones that were good that the tuning seemed pretty close to ideal, but the valves were causing the oil blowby. Basically, its just deciding when to do a full rebuild. I can just do the headwork and put em back on, but the next thing to go would be the bottom end. Or I could just start fresh with a rebuild. Don't get me wrong, the car runs good given that it's 39 years old and was raced from new. I also realize that having it run like it was just driven off the lot yesterday just isn't gonna happpen from dicking around with my carbs. Looks like I have to do a but of figuring to do on my end- to decide if I want it to run like it should, or just let it go until it gets worse, to keep it as original as possible. I just would have a hard time letting it go until the engine blows.

MrMopowered

In case you were wondering, as i'm sure many of you do, my dad plays the whole classic car game for a living. He has for 30+ years. Don't assume I was just handed the keys. I traded him my '71 and bust *** at his shop when i'm not in class. FYI, the whole reason im in college is to help him run it when I get out. Its not like im out to do a full resto, i'm just fixing what needs to be fixed. The work would be done to the motor only- no painting of the engine bay or anything else underhood. I realize how important the car is- that's why i'm asking you guys for advice, as I feel guilty since the car is that original.

MrMopowered

And no stickshifted, I don't drive like a jackass. That means waiting for it to warm up before I drive it, even if i'm just going cruising, let alone to the track (only been 2x). Like I said, i'm not out there running the **** out of it. Yeah the oil is changed regularly. Oh and there is no points- its electronic.

stickshifted

now, did you do a compression test and leakdown yet? we wanna know the compression on all your cylinders - especially the ones with the oily plugs. and leakdown is very important too, because that can help pinpoint what the compression test cant tell you.

also valves dont cause blow-by. blow by is when combustion gases "blow" past your piston rings. it has nothing to do with the valves.

what might have happened to your valves, is that your valve seals might be getting old or cracked, or damaged somehow. they should have mentioned that in "how to rebuild a mopar big block" becuase they talked about it a lot in the rebuilding small block mopars.

when the valve seals arent sealing, it causes some oil to run down the valve and get into the combustion chamber, causeing the engine to burn a oil. and its fairly easy to fix, and you dont even need to pull the heads off to do it. you do the same procedure for each cylinder. you screw an air hose into the clyinder and pressureize it because you dont want a valve to drop into the cylinder. you get a valve spring compressor, take off the retainers, locks and spring, throw the old seal out, put the new one on, then put the spring, retainer and keepers back on and move onto the next cylinder until you done em all. that MIGHT fix one of your problems.

stickshifted

lol i just needed to make sure. wanted to get an idea of how well or how bad the car was being treated.