Bought my First Mopar

[valiant clunker]

So I bought a 68 valiant 4 door for 1500 bucks. Great way to get into mopar i figure. Few questions because I'm new here.

The guy I bought it from put a Pro Comp cam in it, Lift .3026, duration 218

He also said it was bored .030 over.

It runs ok but when I crank it, it sounds like it has no compression. I checked compression and had 75 to 100. Seems to low to me. Also there is a terrible valve tap.

Is the low compression a result of the bored cylinder and/or the cam? It runs really well other than it cranks a lot to start. Also you can smell a lot of raw fuel in the exhaust.

I know ... what do you expect for $1500? Just getting an idea of whether i should mess with what I have or just do a 318 swap.

Thanks

 

[66dartman]

Is it a slant six? Perhaps with that cam your dynamic compression is low, I don't think the slants had a lot of compression from the factory, maybe 8:1. I have always set the timing on slants a little advanced from factory spec, like 5-10 btdc. Might help it start easier, but low compression usually need an engine teardown to repair.

 

[plum crazy dart]

Welcome

 

[valiant clunker]

Its a 273. I did a wet compression check and there was not change. Makes me think the bottom end might be OK. I'm not real familiar with Cams so I'm wondering if the cam he bought isn't right. The valve noise may indicate that I'm not opening my valves properly.
Is there a chance the last guy screwed up mechanical timing? If the chain is off a tooth can it run but with low compression?

 

[william]

You need to do a cylinder leakage test and if all is good no more then 25% check if the cam is timed right.
I would swap out that procomp cam for any other good brand name cam if it was mine.

 

[3404speed]

Hydraulic or mechanical cam and lifters?
Might need valve lash adjusted if it is mechanical.

 

[valiant1966]

Welcome!! Get us a picture when you get a chance.
I would check the timing then the valve lash if it has solid lifters. Then go from there.