When I first joined I started with questions about my chargers 383 hp. It had vacuum issues, brake issues, etc. I won't go on as the list is too long. It took me a little while, to save the money..

We worked on the heads, no change. New cam, lifters pushrods and roller rockers, no change. Oh yeah I have to mention msd billet distributor, 6al2, new msd coil and wires..new intake, little change with that to about as good as it was going to get. Not great!

Well, the new motor went in and the 383 was torn apart. After I put the cam in the 383, I got to second guessing my work and thought I had messed it up. I didn't. Whew! However, the po installed the Pistons way too tight. No end gap in the rings at all. Also the distance from the top of number 1 at tdc was about 150 thousands from the deck. Plus gasket.. No way it would have compression and no way it could get out of its own way!

So I'll save and throw some more money at the 383 and see what happens..

Thanks for everything!

 

By all means.... You have to have compression.... 10.0.1CR
0-decked will wake it up very nice....

 

Absolutely! The stroker that replaced it I shot for 10 compression cane in at 9.7:1 I wanted to run 93 pump gas and it does! That one also zero deck! Scary fast! I love it.. On second test drive after tweaking the carb, doing about 30 mph, hit it and smoked tires and started to come sideways! It was awesome!

Bob, you said way back when I would need to get into the guts of that 383 and I knew you were right but I guessed I hoped it was in the top end!

It should be a relatively easy rebuild as long as I can find the Pistons and rods to bring it up to zero deck. Crank is good, new bearings, new pushrods, I'll look at the cam and see, it's relatively new as well but you never know on that one. I'll need some new roller rockers for it. Oh yeah new pickup tube. I'll probably give it a new oil pump too!

Thanks, I'll keep you posted on that build and how the stoker is going. Once the snow stops!

 

Check With Big Mike over at MRL Performance... He might have some stuff for the rite price for you and not kill you in shipping. Mike is out of the State of Mich.


Keep us posted.... Good Luck... Good to see you here....

 

Frankly, compression ratio does not have that much effect, compared with other design issues. EG is the older cars, old flatheads, some of them down in the 7.x compression ratio area and in some cases lower.

Cam design and timing, and ignition timing has far more to do with vacuum, practically speaking.

 

DDodger,

I think you're right as well. Many factors involved and under normal circumstances to say CR is the lone issue wouldn't be right.. But a little history for this engine. Camshaft was unknown and po said its why brakes were bad due to low vacuum. I replaced with more mild to middle of road cam. Didn't change brakes. Discovered heads had issues valves sticking open and seats at wrong angles. Fixed. Little better but still not what should be. Complete MSD ignition, box, billet dizzy and could and wires. Timing had to be set at initial 21 and all in at 36 (I think) I know initial was high but that is where it needed to be. It ran the best it had at those settings. We played around with timing but got only worse.

We went through everything, timing, cam, carbs, heads etc. the only place we hadn't been is in the block. We knew the car was tight because trying to turn over by hand it was just crazy tight and knuckle busting! We also knew when the heads were off there as zero clearance. At the time I didn't have the to dive completely in. Oh, and I should mention the machine shop the previous owner used, the first thing he said to me was "I didn't install those Pistons"

So, after a long story, I am confident this 383 needs a complete rebuild to make it right. Clearances, Pistons to bring closer to deck, creating some squish!