Engine inspection

[Russ69Runner]

Hello all my Runner brothers. When I open up my 383 and go through it. What should I do to get the best out of it. Yea and while I am at it so the story goes. Have a 650 four barrel carb on it now think it has a light cam in it like a street cam by the way it timed out. Just going to keep the original exhaust manifold on they are in good shape. All ready has a mid rise Holey intake. So what is your thought's. Russ. :redx:

 

[SgtLee511]

Your opening up a can of worms there Russ, cuz theres alot that can be done, but you already making a choice of whats feasable by keeping the original exhaust manifolds, my personal preference is stock engine medium size cam. but 'Im a bit of a purest. I think most these guys will suggest you get in contact with with a company that does alot of mopar work and start there, they can suggest your components. The 383 wasn't a slouch in stock form, good cam and aftermaket heads would you really do it for a good cruiser, I stayed stock mild cam, again I'm a purest. Have Fun.....I remember my Dads 70RR 383, knocking off a 1970 396 Chevelle in 1970 on the Interstate, Again Have Fun, I think its all about how streetable you want it. How rough of an idle at the stop light you can stand etc. My 340 Car is an example I love the car, love the sound but sometimes the idle is just over the top. I suggest deciding how how mutch driving your going to do and what kind of driving your going to do, Car show hopping and to the track once in a while is good for me. Good Luck, cant wait to see what you do my friend.

 

[69hemibeep]

Its your car but I like them slightly modified to where they still drive nice. Big lumpy cam bad idle, hard cold starts,adjusting all the time,special fuel, been there done that. If I want to go that fast I'll build a race car. You need a bit more carb and get one of the new profile cams from Hughes or Comp with a wide LCA it helps with idle and vacuum. You might have a good one in it now, remember the cam is the brains of the motor just don't over do it.

 

[Big John]

IMHO, the stock exhaust manifolds will work just fine. After screwing around with this stuff for a lot of years, I decided that headers are just so much Hot Rod magazine hype and really only needed on cars that had crappy exhaust manifolds to start in with. The HP Mopar manifolds flow well enough for most street applications and don't have the headaches that headers do.

There's a ton of things that need to be taken into consideration for a camshaft choice. Weight, rear end ratio, compression etc. The wrong camshaft choice can make or break your car. I always recommend making a call to a cam company that specializes in Mopar cams and asking for their recommendation. Note the "specialize in Mopar cams" part. What happens with other companies is they develop a camshaft based around a small block Chevy and that camshaft "grind" is then applied to whatever blank is needed. It's ancient technology, but there are still companies doing just that. A lot of guys really like dealing with Hughes.

One other thing.... Less is always more when it comes to street engines. You want to build your engine for the low end. Lot's of torque and a good running engine are key to good street engine. The guy with the over cammed, over carb'd, spark plug fouling mess under the hood might sound cool as it coughs its way into the parking lot, but the good running, low end torque engine will smoke him every time.

 

[CompSyn]

Mr.6pack

A lot of good suggestions in this thread. Here are a couple of mine:

The advertised compression ratio of 10:1 in a stock 68/69 RR 383 was optimistic. 9.2:1 on a good day was more like it. And while there are many aftermarket piston choices out there, last I looked, none have the compression distance of the stock 68/69 383HP. This means getting 9.2:1 or better will require some homework and expensive semi-custom or custom pistons. Compression in the lower 9s isn't necessarily a bad thing if you're going to run stock 906 heads and today's crappy pump gas.

As others have mentioned, 383s are vulnerable to over-camming. When selecting a camshaft for a 383, less can likely mean more. I strongly suggest a call into Bob Karakashian. He really knows how to dial-in stock Mopars.



See also: Bio of Bob Karakashian… ‘Mr Six Pack’ - link

Below a video of Bob's cams in action at the drag strip->
https://youtu.be/OFaPlDt2jt4

 

[CompSyn]

More info. Mr.6pack Camshaft.

Sorry guys but all this talk about camshafts got me exited enough to re-dig up this older thread quote from moparts regarding the Mr.6pack camshaft:

Wayne,

I hear what your saying about camshafts and your right diffrent cams for diffrent apps, Bobs is the best I've found for a stock combo with the stock torque converter. IMHO I dont believe if you throw more lift and duration at the same combo it will ET as well! I dont believe it will idle as well either, 19 to 20in. @750-800 rpm!Thats in my engine!
Wayne, does Ray Barton grind SS/AA cams and advertise lift and duration on his website? Does Dan Davorak grind Max Wedge/Stock eliminator cams and advertise on his site? How about Tri City Comp. no advertisement there either? Maybe Don Little??? No Not on his Homepage???Maybe thats the reason Bob doesnt post the numbers??? Summit Racing or Jegs does advertise lift and duration for around $49.99 or something like that, (Just Pullin your tail as my son would say) Bobs helped me many many times over the years and others by this post and I know he would never never look down on anybody thats why I posted.Mr Six Pack is genuine Nice Guy as Mike has said and his goal in all these years of doing this is to help make the Mopars stand tall and run the number! See ya at Martin in the rental racer?

Brad,

Bob designed his cam to as close as posssible to the original 69 440 low taper design six pack cam, it is not a low taper but as close as he could make it to the original with what cores are avail. Bob did measure and try to duplicate his cam to the 69 cam. The question you asked me Yes, I did compair and measure Bobs cam also to my six pack cam and I also compaired a (about 98/99)version of Mopars Resto cam and a Crane Resto cam all to each other, I believe that the crane and mopar were one and the same even the paint stripe on the core was the same, I sold both of the Resto cams after that, a couple of years later I had the chance to look at a Comp cam resto cam and it was simalar to the Crane cam, nowhere near my original. Thats all that I've checked I know there are others but I havent went further.
The whole reason that Bob even made this cam was because his orignal was getting worn and he could not come up with an identical replacement he wasnt trying to become a Cam Company, he just needed a duplacate to his orignal cam, the resto cams that he used never ET as well as the orignal low taper cam so the cam he has now is as close as can be made now, he started selling the cams because all of us locals wanted to run one after seeing his track performance with his car thats why he started selling them. The cam thats in his car is the same one he sells to the guys that race with him, I've checked that also, helped him tear down and certify and the cam specs have always been the same as the one he sells,in My car, Jims Bee, Steves car, Jim S car and all of the others.

One of our Friends once said Bob will help you to beat him on the track, thats the kind of Person he is.

Thanks Guys, sorry its too long

Paul M Petcou

Cited link: http://board.moparts.org/ubbthreads/ubbthreads.php/topics/32584/5.html

I've spoken with Bob on the phone and have acquired his camshaft for my stock 383HP. I don't have my engine or Road Runner together yet so I can't comment on how will the cam does in my stock combo. I'd image in the 383 this cam will be a bit more loopy versus the 440 application which is said to be grandma 318 mellow as far as idle quality goes.